 cee308312a
			
		
	
	cee308312a
	
	
	
		
			
			folowing additional options: --enable-w32threads, --arch=i686 (for 32-bit library, workaround for http://trac.ffmpeg.org/ticket/2363)
		
			
				
	
	
		
			2182 lines
		
	
	
		
			80 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			2182 lines
		
	
	
		
			80 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * copyright (c) 2001 Fabrice Bellard
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|  *
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|  * This file is part of FFmpeg.
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|  *
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|  * FFmpeg is free software; you can redistribute it and/or
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|  * modify it under the terms of the GNU Lesser General Public
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|  * License as published by the Free Software Foundation; either
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|  * version 2.1 of the License, or (at your option) any later version.
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|  *
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|  * FFmpeg is distributed in the hope that it will be useful,
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|  * but WITHOUT ANY WARRANTY; without even the implied warranty of
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|  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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|  * Lesser General Public License for more details.
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|  *
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|  * You should have received a copy of the GNU Lesser General Public
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|  * License along with FFmpeg; if not, write to the Free Software
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|  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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|  */
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| 
 | |
| #ifndef AVFORMAT_AVFORMAT_H
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| #define AVFORMAT_AVFORMAT_H
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| 
 | |
| /**
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|  * @file
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|  * @ingroup libavf
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|  * Main libavformat public API header
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|  */
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| 
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| /**
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|  * @defgroup libavf I/O and Muxing/Demuxing Library
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|  * @{
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|  *
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|  * Libavformat (lavf) is a library for dealing with various media container
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|  * formats. Its main two purposes are demuxing - i.e. splitting a media file
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|  * into component streams, and the reverse process of muxing - writing supplied
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|  * data in a specified container format. It also has an @ref lavf_io
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|  * "I/O module" which supports a number of protocols for accessing the data (e.g.
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|  * file, tcp, http and others). Before using lavf, you need to call
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|  * av_register_all() to register all compiled muxers, demuxers and protocols.
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|  * Unless you are absolutely sure you won't use libavformat's network
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|  * capabilities, you should also call avformat_network_init().
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|  *
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|  * A supported input format is described by an AVInputFormat struct, conversely
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|  * an output format is described by AVOutputFormat. You can iterate over all
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|  * registered input/output formats using the av_iformat_next() /
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|  * av_oformat_next() functions. The protocols layer is not part of the public
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|  * API, so you can only get the names of supported protocols with the
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|  * avio_enum_protocols() function.
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|  *
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|  * Main lavf structure used for both muxing and demuxing is AVFormatContext,
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|  * which exports all information about the file being read or written. As with
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|  * most Libavformat structures, its size is not part of public ABI, so it cannot be
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|  * allocated on stack or directly with av_malloc(). To create an
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|  * AVFormatContext, use avformat_alloc_context() (some functions, like
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|  * avformat_open_input() might do that for you).
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|  *
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|  * Most importantly an AVFormatContext contains:
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|  * @li the @ref AVFormatContext.iformat "input" or @ref AVFormatContext.oformat
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|  * "output" format. It is either autodetected or set by user for input;
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|  * always set by user for output.
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|  * @li an @ref AVFormatContext.streams "array" of AVStreams, which describe all
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|  * elementary streams stored in the file. AVStreams are typically referred to
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|  * using their index in this array.
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|  * @li an @ref AVFormatContext.pb "I/O context". It is either opened by lavf or
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|  * set by user for input, always set by user for output (unless you are dealing
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|  * with an AVFMT_NOFILE format).
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|  *
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|  * @section lavf_options Passing options to (de)muxers
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|  * Lavf allows to configure muxers and demuxers using the @ref avoptions
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|  * mechanism. Generic (format-independent) libavformat options are provided by
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|  * AVFormatContext, they can be examined from a user program by calling
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|  * av_opt_next() / av_opt_find() on an allocated AVFormatContext (or its AVClass
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|  * from avformat_get_class()). Private (format-specific) options are provided by
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|  * AVFormatContext.priv_data if and only if AVInputFormat.priv_class /
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|  * AVOutputFormat.priv_class of the corresponding format struct is non-NULL.
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|  * Further options may be provided by the @ref AVFormatContext.pb "I/O context",
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|  * if its AVClass is non-NULL, and the protocols layer. See the discussion on
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|  * nesting in @ref avoptions documentation to learn how to access those.
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|  *
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|  * @defgroup lavf_decoding Demuxing
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|  * @{
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|  * Demuxers read a media file and split it into chunks of data (@em packets). A
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|  * @ref AVPacket "packet" contains one or more encoded frames which belongs to a
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|  * single elementary stream. In the lavf API this process is represented by the
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|  * avformat_open_input() function for opening a file, av_read_frame() for
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|  * reading a single packet and finally avformat_close_input(), which does the
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|  * cleanup.
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|  *
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|  * @section lavf_decoding_open Opening a media file
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|  * The minimum information required to open a file is its URL or filename, which
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|  * is passed to avformat_open_input(), as in the following code:
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|  * @code
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|  * const char    *url = "in.mp3";
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|  * AVFormatContext *s = NULL;
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|  * int ret = avformat_open_input(&s, url, NULL, NULL);
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|  * if (ret < 0)
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|  *     abort();
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|  * @endcode
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|  * The above code attempts to allocate an AVFormatContext, open the
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|  * specified file (autodetecting the format) and read the header, exporting the
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|  * information stored there into s. Some formats do not have a header or do not
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|  * store enough information there, so it is recommended that you call the
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|  * avformat_find_stream_info() function which tries to read and decode a few
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|  * frames to find missing information.
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|  *
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|  * In some cases you might want to preallocate an AVFormatContext yourself with
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|  * avformat_alloc_context() and do some tweaking on it before passing it to
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|  * avformat_open_input(). One such case is when you want to use custom functions
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|  * for reading input data instead of lavf internal I/O layer.
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|  * To do that, create your own AVIOContext with avio_alloc_context(), passing
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|  * your reading callbacks to it. Then set the @em pb field of your
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|  * AVFormatContext to newly created AVIOContext.
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|  *
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|  * Since the format of the opened file is in general not known until after
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|  * avformat_open_input() has returned, it is not possible to set demuxer private
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|  * options on a preallocated context. Instead, the options should be passed to
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|  * avformat_open_input() wrapped in an AVDictionary:
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|  * @code
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|  * AVDictionary *options = NULL;
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|  * av_dict_set(&options, "video_size", "640x480", 0);
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|  * av_dict_set(&options, "pixel_format", "rgb24", 0);
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|  *
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|  * if (avformat_open_input(&s, url, NULL, &options) < 0)
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|  *     abort();
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|  * av_dict_free(&options);
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|  * @endcode
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|  * This code passes the private options 'video_size' and 'pixel_format' to the
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|  * demuxer. They would be necessary for e.g. the rawvideo demuxer, since it
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|  * cannot know how to interpret raw video data otherwise. If the format turns
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|  * out to be something different than raw video, those options will not be
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|  * recognized by the demuxer and therefore will not be applied. Such unrecognized
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|  * options are then returned in the options dictionary (recognized options are
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|  * consumed). The calling program can handle such unrecognized options as it
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|  * wishes, e.g.
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|  * @code
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|  * AVDictionaryEntry *e;
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|  * if (e = av_dict_get(options, "", NULL, AV_DICT_IGNORE_SUFFIX)) {
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|  *     fprintf(stderr, "Option %s not recognized by the demuxer.\n", e->key);
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|  *     abort();
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|  * }
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|  * @endcode
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|  *
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|  * After you have finished reading the file, you must close it with
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|  * avformat_close_input(). It will free everything associated with the file.
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|  *
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|  * @section lavf_decoding_read Reading from an opened file
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|  * Reading data from an opened AVFormatContext is done by repeatedly calling
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|  * av_read_frame() on it. Each call, if successful, will return an AVPacket
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|  * containing encoded data for one AVStream, identified by
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|  * AVPacket.stream_index. This packet may be passed straight into the libavcodec
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|  * decoding functions avcodec_decode_video2(), avcodec_decode_audio4() or
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|  * avcodec_decode_subtitle2() if the caller wishes to decode the data.
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|  *
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|  * AVPacket.pts, AVPacket.dts and AVPacket.duration timing information will be
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|  * set if known. They may also be unset (i.e. AV_NOPTS_VALUE for
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|  * pts/dts, 0 for duration) if the stream does not provide them. The timing
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|  * information will be in AVStream.time_base units, i.e. it has to be
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|  * multiplied by the timebase to convert them to seconds.
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|  *
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|  * If AVPacket.buf is set on the returned packet, then the packet is
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|  * allocated dynamically and the user may keep it indefinitely.
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|  * Otherwise, if AVPacket.buf is NULL, the packet data is backed by a
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|  * static storage somewhere inside the demuxer and the packet is only valid
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|  * until the next av_read_frame() call or closing the file. If the caller
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|  * requires a longer lifetime, av_dup_packet() will make an av_malloc()ed copy
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|  * of it.
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|  * In both cases, the packet must be freed with av_free_packet() when it is no
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|  * longer needed.
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|  *
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|  * @section lavf_decoding_seek Seeking
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|  * @}
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|  *
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|  * @defgroup lavf_encoding Muxing
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|  * @{
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|  * @}
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|  *
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|  * @defgroup lavf_io I/O Read/Write
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|  * @{
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|  * @}
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|  *
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|  * @defgroup lavf_codec Demuxers
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|  * @{
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|  * @defgroup lavf_codec_native Native Demuxers
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|  * @{
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|  * @}
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|  * @defgroup lavf_codec_wrappers External library wrappers
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|  * @{
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|  * @}
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|  * @}
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|  * @defgroup lavf_protos I/O Protocols
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|  * @{
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|  * @}
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|  * @defgroup lavf_internal Internal
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|  * @{
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|  * @}
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|  * @}
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|  *
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|  */
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| 
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| #include <time.h>
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| #include <stdio.h>  /* FILE */
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| #include "libavcodec/avcodec.h"
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| #include "libavutil/dict.h"
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| #include "libavutil/log.h"
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| 
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| #include "avio.h"
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| #include "libavformat/version.h"
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| 
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| struct AVFormatContext;
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| 
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| 
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| /**
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|  * @defgroup metadata_api Public Metadata API
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|  * @{
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|  * @ingroup libavf
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|  * The metadata API allows libavformat to export metadata tags to a client
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|  * application when demuxing. Conversely it allows a client application to
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|  * set metadata when muxing.
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|  *
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|  * Metadata is exported or set as pairs of key/value strings in the 'metadata'
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|  * fields of the AVFormatContext, AVStream, AVChapter and AVProgram structs
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|  * using the @ref lavu_dict "AVDictionary" API. Like all strings in FFmpeg,
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|  * metadata is assumed to be UTF-8 encoded Unicode. Note that metadata
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|  * exported by demuxers isn't checked to be valid UTF-8 in most cases.
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|  *
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|  * Important concepts to keep in mind:
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|  * -  Keys are unique; there can never be 2 tags with the same key. This is
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|  *    also meant semantically, i.e., a demuxer should not knowingly produce
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|  *    several keys that are literally different but semantically identical.
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|  *    E.g., key=Author5, key=Author6. In this example, all authors must be
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|  *    placed in the same tag.
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|  * -  Metadata is flat, not hierarchical; there are no subtags. If you
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|  *    want to store, e.g., the email address of the child of producer Alice
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|  *    and actor Bob, that could have key=alice_and_bobs_childs_email_address.
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|  * -  Several modifiers can be applied to the tag name. This is done by
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|  *    appending a dash character ('-') and the modifier name in the order
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|  *    they appear in the list below -- e.g. foo-eng-sort, not foo-sort-eng.
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|  *    -  language -- a tag whose value is localized for a particular language
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|  *       is appended with the ISO 639-2/B 3-letter language code.
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|  *       For example: Author-ger=Michael, Author-eng=Mike
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|  *       The original/default language is in the unqualified "Author" tag.
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|  *       A demuxer should set a default if it sets any translated tag.
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|  *    -  sorting  -- a modified version of a tag that should be used for
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|  *       sorting will have '-sort' appended. E.g. artist="The Beatles",
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|  *       artist-sort="Beatles, The".
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|  *
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|  * -  Demuxers attempt to export metadata in a generic format, however tags
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|  *    with no generic equivalents are left as they are stored in the container.
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|  *    Follows a list of generic tag names:
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|  *
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|  @verbatim
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|  album        -- name of the set this work belongs to
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|  album_artist -- main creator of the set/album, if different from artist.
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|                  e.g. "Various Artists" for compilation albums.
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|  artist       -- main creator of the work
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|  comment      -- any additional description of the file.
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|  composer     -- who composed the work, if different from artist.
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|  copyright    -- name of copyright holder.
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|  creation_time-- date when the file was created, preferably in ISO 8601.
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|  date         -- date when the work was created, preferably in ISO 8601.
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|  disc         -- number of a subset, e.g. disc in a multi-disc collection.
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|  encoder      -- name/settings of the software/hardware that produced the file.
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|  encoded_by   -- person/group who created the file.
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|  filename     -- original name of the file.
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|  genre        -- <self-evident>.
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|  language     -- main language in which the work is performed, preferably
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|                  in ISO 639-2 format. Multiple languages can be specified by
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|                  separating them with commas.
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|  performer    -- artist who performed the work, if different from artist.
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|                  E.g for "Also sprach Zarathustra", artist would be "Richard
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|                  Strauss" and performer "London Philharmonic Orchestra".
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|  publisher    -- name of the label/publisher.
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|  service_name     -- name of the service in broadcasting (channel name).
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|  service_provider -- name of the service provider in broadcasting.
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|  title        -- name of the work.
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|  track        -- number of this work in the set, can be in form current/total.
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|  variant_bitrate -- the total bitrate of the bitrate variant that the current stream is part of
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|  @endverbatim
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|  *
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|  * Look in the examples section for an application example how to use the Metadata API.
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|  *
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|  * @}
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|  */
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| 
 | |
| /* packet functions */
 | |
| 
 | |
| 
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| /**
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|  * Allocate and read the payload of a packet and initialize its
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|  * fields with default values.
 | |
|  *
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|  * @param pkt packet
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|  * @param size desired payload size
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|  * @return >0 (read size) if OK, AVERROR_xxx otherwise
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|  */
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| int av_get_packet(AVIOContext *s, AVPacket *pkt, int size);
 | |
| 
 | |
| 
 | |
| /**
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|  * Read data and append it to the current content of the AVPacket.
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|  * If pkt->size is 0 this is identical to av_get_packet.
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|  * Note that this uses av_grow_packet and thus involves a realloc
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|  * which is inefficient. Thus this function should only be used
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|  * when there is no reasonable way to know (an upper bound of)
 | |
|  * the final size.
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|  *
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|  * @param pkt packet
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|  * @param size amount of data to read
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|  * @return >0 (read size) if OK, AVERROR_xxx otherwise, previous data
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|  *         will not be lost even if an error occurs.
 | |
|  */
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| int av_append_packet(AVIOContext *s, AVPacket *pkt, int size);
 | |
| 
 | |
| /*************************************************/
 | |
| /* fractional numbers for exact pts handling */
 | |
| 
 | |
| /**
 | |
|  * The exact value of the fractional number is: 'val + num / den'.
 | |
|  * num is assumed to be 0 <= num < den.
 | |
|  */
 | |
| typedef struct AVFrac {
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|     int64_t val, num, den;
 | |
| } AVFrac;
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| 
 | |
| /*************************************************/
 | |
| /* input/output formats */
 | |
| 
 | |
| struct AVCodecTag;
 | |
| 
 | |
| /**
 | |
|  * This structure contains the data a format has to probe a file.
 | |
|  */
 | |
| typedef struct AVProbeData {
 | |
|     const char *filename;
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|     unsigned char *buf; /**< Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero. */
 | |
|     int buf_size;       /**< Size of buf except extra allocated bytes */
 | |
| } AVProbeData;
 | |
| 
 | |
| #define AVPROBE_SCORE_RETRY (AVPROBE_SCORE_MAX/4)
 | |
| #define AVPROBE_SCORE_EXTENSION  50 ///< score for file extension
 | |
| #define AVPROBE_SCORE_MAX       100 ///< maximum score
 | |
| 
 | |
| #define AVPROBE_PADDING_SIZE 32             ///< extra allocated bytes at the end of the probe buffer
 | |
| 
 | |
| /// Demuxer will use avio_open, no opened file should be provided by the caller.
 | |
| #define AVFMT_NOFILE        0x0001
 | |
| #define AVFMT_NEEDNUMBER    0x0002 /**< Needs '%d' in filename. */
 | |
| #define AVFMT_SHOW_IDS      0x0008 /**< Show format stream IDs numbers. */
 | |
| #define AVFMT_RAWPICTURE    0x0020 /**< Format wants AVPicture structure for
 | |
|                                       raw picture data. */
 | |
| #define AVFMT_GLOBALHEADER  0x0040 /**< Format wants global header. */
 | |
| #define AVFMT_NOTIMESTAMPS  0x0080 /**< Format does not need / have any timestamps. */
 | |
| #define AVFMT_GENERIC_INDEX 0x0100 /**< Use generic index building code. */
 | |
| #define AVFMT_TS_DISCONT    0x0200 /**< Format allows timestamp discontinuities. Note, muxers always require valid (monotone) timestamps */
 | |
| #define AVFMT_VARIABLE_FPS  0x0400 /**< Format allows variable fps. */
 | |
| #define AVFMT_NODIMENSIONS  0x0800 /**< Format does not need width/height */
 | |
| #define AVFMT_NOSTREAMS     0x1000 /**< Format does not require any streams */
 | |
| #define AVFMT_NOBINSEARCH   0x2000 /**< Format does not allow to fall back on binary search via read_timestamp */
 | |
| #define AVFMT_NOGENSEARCH   0x4000 /**< Format does not allow to fall back on generic search */
 | |
| #define AVFMT_NO_BYTE_SEEK  0x8000 /**< Format does not allow seeking by bytes */
 | |
| #define AVFMT_ALLOW_FLUSH  0x10000 /**< Format allows flushing. If not set, the muxer will not receive a NULL packet in the write_packet function. */
 | |
| #if LIBAVFORMAT_VERSION_MAJOR <= 54
 | |
| #define AVFMT_TS_NONSTRICT 0x8020000 //we try to be compatible to the ABIs of ffmpeg and major forks
 | |
| #else
 | |
| #define AVFMT_TS_NONSTRICT 0x20000
 | |
| #endif
 | |
|                                    /**< Format does not require strictly
 | |
|                                         increasing timestamps, but they must
 | |
|                                         still be monotonic */
 | |
| #define AVFMT_TS_NEGATIVE  0x40000 /**< Format allows muxing negative
 | |
|                                         timestamps. If not set the timestamp
 | |
|                                         will be shifted in av_write_frame and
 | |
|                                         av_interleaved_write_frame so they
 | |
|                                         start from 0.
 | |
|                                         The user or muxer can override this through
 | |
|                                         AVFormatContext.avoid_negative_ts
 | |
|                                         */
 | |
| 
 | |
| #define AVFMT_SEEK_TO_PTS   0x4000000 /**< Seeking is based on PTS */
 | |
| 
 | |
| /**
 | |
|  * @addtogroup lavf_encoding
 | |
|  * @{
 | |
|  */
 | |
| typedef struct AVOutputFormat {
 | |
|     const char *name;
 | |
|     /**
 | |
|      * Descriptive name for the format, meant to be more human-readable
 | |
|      * than name. You should use the NULL_IF_CONFIG_SMALL() macro
 | |
|      * to define it.
 | |
|      */
 | |
|     const char *long_name;
 | |
|     const char *mime_type;
 | |
|     const char *extensions; /**< comma-separated filename extensions */
 | |
|     /* output support */
 | |
|     enum AVCodecID audio_codec;    /**< default audio codec */
 | |
|     enum AVCodecID video_codec;    /**< default video codec */
 | |
|     enum AVCodecID subtitle_codec; /**< default subtitle codec */
 | |
|     /**
 | |
|      * can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_RAWPICTURE,
 | |
|      * AVFMT_GLOBALHEADER, AVFMT_NOTIMESTAMPS, AVFMT_VARIABLE_FPS,
 | |
|      * AVFMT_NODIMENSIONS, AVFMT_NOSTREAMS, AVFMT_ALLOW_FLUSH,
 | |
|      * AVFMT_TS_NONSTRICT
 | |
|      */
 | |
|     int flags;
 | |
| 
 | |
|     /**
 | |
|      * List of supported codec_id-codec_tag pairs, ordered by "better
 | |
|      * choice first". The arrays are all terminated by AV_CODEC_ID_NONE.
 | |
|      */
 | |
|     const struct AVCodecTag * const *codec_tag;
 | |
| 
 | |
| 
 | |
|     const AVClass *priv_class; ///< AVClass for the private context
 | |
| 
 | |
|     /*****************************************************************
 | |
|      * No fields below this line are part of the public API. They
 | |
|      * may not be used outside of libavformat and can be changed and
 | |
|      * removed at will.
 | |
|      * New public fields should be added right above.
 | |
|      *****************************************************************
 | |
|      */
 | |
|     struct AVOutputFormat *next;
 | |
|     /**
 | |
|      * size of private data so that it can be allocated in the wrapper
 | |
|      */
 | |
|     int priv_data_size;
 | |
| 
 | |
|     int (*write_header)(struct AVFormatContext *);
 | |
|     /**
 | |
|      * Write a packet. If AVFMT_ALLOW_FLUSH is set in flags,
 | |
|      * pkt can be NULL in order to flush data buffered in the muxer.
 | |
|      * When flushing, return 0 if there still is more data to flush,
 | |
|      * or 1 if everything was flushed and there is no more buffered
 | |
|      * data.
 | |
|      */
 | |
|     int (*write_packet)(struct AVFormatContext *, AVPacket *pkt);
 | |
|     int (*write_trailer)(struct AVFormatContext *);
 | |
|     /**
 | |
|      * Currently only used to set pixel format if not YUV420P.
 | |
|      */
 | |
|     int (*interleave_packet)(struct AVFormatContext *, AVPacket *out,
 | |
|                              AVPacket *in, int flush);
 | |
|     /**
 | |
|      * Test if the given codec can be stored in this container.
 | |
|      *
 | |
|      * @return 1 if the codec is supported, 0 if it is not.
 | |
|      *         A negative number if unknown.
 | |
|      *         MKTAG('A', 'P', 'I', 'C') if the codec is only supported as AV_DISPOSITION_ATTACHED_PIC
 | |
|      */
 | |
|     int (*query_codec)(enum AVCodecID id, int std_compliance);
 | |
| 
 | |
|     void (*get_output_timestamp)(struct AVFormatContext *s, int stream,
 | |
|                                  int64_t *dts, int64_t *wall);
 | |
| } AVOutputFormat;
 | |
| /**
 | |
|  * @}
 | |
|  */
 | |
| 
 | |
| /**
 | |
|  * @addtogroup lavf_decoding
 | |
|  * @{
 | |
|  */
 | |
| typedef struct AVInputFormat {
 | |
|     /**
 | |
|      * A comma separated list of short names for the format. New names
 | |
|      * may be appended with a minor bump.
 | |
|      */
 | |
|     const char *name;
 | |
| 
 | |
|     /**
 | |
|      * Descriptive name for the format, meant to be more human-readable
 | |
|      * than name. You should use the NULL_IF_CONFIG_SMALL() macro
 | |
|      * to define it.
 | |
|      */
 | |
|     const char *long_name;
 | |
| 
 | |
|     /**
 | |
|      * Can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_SHOW_IDS,
 | |
|      * AVFMT_GENERIC_INDEX, AVFMT_TS_DISCONT, AVFMT_NOBINSEARCH,
 | |
|      * AVFMT_NOGENSEARCH, AVFMT_NO_BYTE_SEEK, AVFMT_SEEK_TO_PTS.
 | |
|      */
 | |
|     int flags;
 | |
| 
 | |
|     /**
 | |
|      * If extensions are defined, then no probe is done. You should
 | |
|      * usually not use extension format guessing because it is not
 | |
|      * reliable enough
 | |
|      */
 | |
|     const char *extensions;
 | |
| 
 | |
|     const struct AVCodecTag * const *codec_tag;
 | |
| 
 | |
|     const AVClass *priv_class; ///< AVClass for the private context
 | |
| 
 | |
|     /*****************************************************************
 | |
|      * No fields below this line are part of the public API. They
 | |
|      * may not be used outside of libavformat and can be changed and
 | |
|      * removed at will.
 | |
|      * New public fields should be added right above.
 | |
|      *****************************************************************
 | |
|      */
 | |
|     struct AVInputFormat *next;
 | |
| 
 | |
|     /**
 | |
|      * Raw demuxers store their codec ID here.
 | |
|      */
 | |
|     int raw_codec_id;
 | |
| 
 | |
|     /**
 | |
|      * Size of private data so that it can be allocated in the wrapper.
 | |
|      */
 | |
|     int priv_data_size;
 | |
| 
 | |
|     /**
 | |
|      * Tell if a given file has a chance of being parsed as this format.
 | |
|      * The buffer provided is guaranteed to be AVPROBE_PADDING_SIZE bytes
 | |
|      * big so you do not have to check for that unless you need more.
 | |
|      */
 | |
|     int (*read_probe)(AVProbeData *);
 | |
| 
 | |
|     /**
 | |
|      * Read the format header and initialize the AVFormatContext
 | |
|      * structure. Return 0 if OK. Only used in raw format right
 | |
|      * now. 'avformat_new_stream' should be called to create new streams.
 | |
|      */
 | |
|     int (*read_header)(struct AVFormatContext *);
 | |
| 
 | |
|     /**
 | |
|      * Read one packet and put it in 'pkt'. pts and flags are also
 | |
|      * set. 'avformat_new_stream' can be called only if the flag
 | |
|      * AVFMTCTX_NOHEADER is used and only in the calling thread (not in a
 | |
|      * background thread).
 | |
|      * @return 0 on success, < 0 on error.
 | |
|      *         When returning an error, pkt must not have been allocated
 | |
|      *         or must be freed before returning
 | |
|      */
 | |
|     int (*read_packet)(struct AVFormatContext *, AVPacket *pkt);
 | |
| 
 | |
|     /**
 | |
|      * Close the stream. The AVFormatContext and AVStreams are not
 | |
|      * freed by this function
 | |
|      */
 | |
|     int (*read_close)(struct AVFormatContext *);
 | |
| 
 | |
|     /**
 | |
|      * Seek to a given timestamp relative to the frames in
 | |
|      * stream component stream_index.
 | |
|      * @param stream_index Must not be -1.
 | |
|      * @param flags Selects which direction should be preferred if no exact
 | |
|      *              match is available.
 | |
|      * @return >= 0 on success (but not necessarily the new offset)
 | |
|      */
 | |
|     int (*read_seek)(struct AVFormatContext *,
 | |
|                      int stream_index, int64_t timestamp, int flags);
 | |
| 
 | |
|     /**
 | |
|      * Get the next timestamp in stream[stream_index].time_base units.
 | |
|      * @return the timestamp or AV_NOPTS_VALUE if an error occurred
 | |
|      */
 | |
|     int64_t (*read_timestamp)(struct AVFormatContext *s, int stream_index,
 | |
|                               int64_t *pos, int64_t pos_limit);
 | |
| 
 | |
|     /**
 | |
|      * Start/resume playing - only meaningful if using a network-based format
 | |
|      * (RTSP).
 | |
|      */
 | |
|     int (*read_play)(struct AVFormatContext *);
 | |
| 
 | |
|     /**
 | |
|      * Pause playing - only meaningful if using a network-based format
 | |
|      * (RTSP).
 | |
|      */
 | |
|     int (*read_pause)(struct AVFormatContext *);
 | |
| 
 | |
|     /**
 | |
|      * Seek to timestamp ts.
 | |
|      * Seeking will be done so that the point from which all active streams
 | |
|      * can be presented successfully will be closest to ts and within min/max_ts.
 | |
|      * Active streams are all streams that have AVStream.discard < AVDISCARD_ALL.
 | |
|      */
 | |
|     int (*read_seek2)(struct AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags);
 | |
| } AVInputFormat;
 | |
| /**
 | |
|  * @}
 | |
|  */
 | |
| 
 | |
| enum AVStreamParseType {
 | |
|     AVSTREAM_PARSE_NONE,
 | |
|     AVSTREAM_PARSE_FULL,       /**< full parsing and repack */
 | |
|     AVSTREAM_PARSE_HEADERS,    /**< Only parse headers, do not repack. */
 | |
|     AVSTREAM_PARSE_TIMESTAMPS, /**< full parsing and interpolation of timestamps for frames not starting on a packet boundary */
 | |
|     AVSTREAM_PARSE_FULL_ONCE,  /**< full parsing and repack of the first frame only, only implemented for H.264 currently */
 | |
|     AVSTREAM_PARSE_FULL_RAW=MKTAG(0,'R','A','W'),       /**< full parsing and repack with timestamp and position generation by parser for raw
 | |
|                                                              this assumes that each packet in the file contains no demuxer level headers and
 | |
|                                                              just codec level data, otherwise position generation would fail */
 | |
| };
 | |
| 
 | |
| typedef struct AVIndexEntry {
 | |
|     int64_t pos;
 | |
|     int64_t timestamp;        /**<
 | |
|                                * Timestamp in AVStream.time_base units, preferably the time from which on correctly decoded frames are available
 | |
|                                * when seeking to this entry. That means preferable PTS on keyframe based formats.
 | |
|                                * But demuxers can choose to store a different timestamp, if it is more convenient for the implementation or nothing better
 | |
|                                * is known
 | |
|                                */
 | |
| #define AVINDEX_KEYFRAME 0x0001
 | |
|     int flags:2;
 | |
|     int size:30; //Yeah, trying to keep the size of this small to reduce memory requirements (it is 24 vs. 32 bytes due to possible 8-byte alignment).
 | |
|     int min_distance;         /**< Minimum distance between this and the previous keyframe, used to avoid unneeded searching. */
 | |
| } AVIndexEntry;
 | |
| 
 | |
| #define AV_DISPOSITION_DEFAULT   0x0001
 | |
| #define AV_DISPOSITION_DUB       0x0002
 | |
| #define AV_DISPOSITION_ORIGINAL  0x0004
 | |
| #define AV_DISPOSITION_COMMENT   0x0008
 | |
| #define AV_DISPOSITION_LYRICS    0x0010
 | |
| #define AV_DISPOSITION_KARAOKE   0x0020
 | |
| 
 | |
| /**
 | |
|  * Track should be used during playback by default.
 | |
|  * Useful for subtitle track that should be displayed
 | |
|  * even when user did not explicitly ask for subtitles.
 | |
|  */
 | |
| #define AV_DISPOSITION_FORCED    0x0040
 | |
| #define AV_DISPOSITION_HEARING_IMPAIRED  0x0080  /**< stream for hearing impaired audiences */
 | |
| #define AV_DISPOSITION_VISUAL_IMPAIRED   0x0100  /**< stream for visual impaired audiences */
 | |
| #define AV_DISPOSITION_CLEAN_EFFECTS     0x0200  /**< stream without voice */
 | |
| /**
 | |
|  * The stream is stored in the file as an attached picture/"cover art" (e.g.
 | |
|  * APIC frame in ID3v2). The single packet associated with it will be returned
 | |
|  * among the first few packets read from the file unless seeking takes place.
 | |
|  * It can also be accessed at any time in AVStream.attached_pic.
 | |
|  */
 | |
| #define AV_DISPOSITION_ATTACHED_PIC      0x0400
 | |
| 
 | |
| /**
 | |
|  * To specify text track kind (different from subtitles default).
 | |
|  */
 | |
| #define AV_DISPOSITION_CAPTIONS     0x10000
 | |
| #define AV_DISPOSITION_DESCRIPTIONS 0x20000
 | |
| #define AV_DISPOSITION_METADATA     0x40000
 | |
| 
 | |
| /**
 | |
|  * Options for behavior on timestamp wrap detection.
 | |
|  */
 | |
| #define AV_PTS_WRAP_IGNORE      0   ///< ignore the wrap
 | |
| #define AV_PTS_WRAP_ADD_OFFSET  1   ///< add the format specific offset on wrap detection
 | |
| #define AV_PTS_WRAP_SUB_OFFSET  -1  ///< subtract the format specific offset on wrap detection
 | |
| 
 | |
| /**
 | |
|  * Stream structure.
 | |
|  * New fields can be added to the end with minor version bumps.
 | |
|  * Removal, reordering and changes to existing fields require a major
 | |
|  * version bump.
 | |
|  * sizeof(AVStream) must not be used outside libav*.
 | |
|  */
 | |
| typedef struct AVStream {
 | |
|     int index;    /**< stream index in AVFormatContext */
 | |
|     /**
 | |
|      * Format-specific stream ID.
 | |
|      * decoding: set by libavformat
 | |
|      * encoding: set by the user, replaced by libavformat if left unset
 | |
|      */
 | |
|     int id;
 | |
|     /**
 | |
|      * Codec context associated with this stream. Allocated and freed by
 | |
|      * libavformat.
 | |
|      *
 | |
|      * - decoding: The demuxer exports codec information stored in the headers
 | |
|      *             here.
 | |
|      * - encoding: The user sets codec information, the muxer writes it to the
 | |
|      *             output. Mandatory fields as specified in AVCodecContext
 | |
|      *             documentation must be set even if this AVCodecContext is
 | |
|      *             not actually used for encoding.
 | |
|      */
 | |
|     AVCodecContext *codec;
 | |
|     void *priv_data;
 | |
| 
 | |
|     /**
 | |
|      * encoding: pts generation when outputting stream
 | |
|      */
 | |
|     struct AVFrac pts;
 | |
| 
 | |
|     /**
 | |
|      * This is the fundamental unit of time (in seconds) in terms
 | |
|      * of which frame timestamps are represented.
 | |
|      *
 | |
|      * decoding: set by libavformat
 | |
|      * encoding: set by libavformat in avformat_write_header. The muxer may use the
 | |
|      * user-provided value of @ref AVCodecContext.time_base "codec->time_base"
 | |
|      * as a hint.
 | |
|      */
 | |
|     AVRational time_base;
 | |
| 
 | |
|     /**
 | |
|      * Decoding: pts of the first frame of the stream in presentation order, in stream time base.
 | |
|      * Only set this if you are absolutely 100% sure that the value you set
 | |
|      * it to really is the pts of the first frame.
 | |
|      * This may be undefined (AV_NOPTS_VALUE).
 | |
|      * @note The ASF header does NOT contain a correct start_time the ASF
 | |
|      * demuxer must NOT set this.
 | |
|      */
 | |
|     int64_t start_time;
 | |
| 
 | |
|     /**
 | |
|      * Decoding: duration of the stream, in stream time base.
 | |
|      * If a source file does not specify a duration, but does specify
 | |
|      * a bitrate, this value will be estimated from bitrate and file size.
 | |
|      */
 | |
|     int64_t duration;
 | |
| 
 | |
|     int64_t nb_frames;                 ///< number of frames in this stream if known or 0
 | |
| 
 | |
|     int disposition; /**< AV_DISPOSITION_* bit field */
 | |
| 
 | |
|     enum AVDiscard discard; ///< Selects which packets can be discarded at will and do not need to be demuxed.
 | |
| 
 | |
|     /**
 | |
|      * sample aspect ratio (0 if unknown)
 | |
|      * - encoding: Set by user.
 | |
|      * - decoding: Set by libavformat.
 | |
|      */
 | |
|     AVRational sample_aspect_ratio;
 | |
| 
 | |
|     AVDictionary *metadata;
 | |
| 
 | |
|     /**
 | |
|      * Average framerate
 | |
|      */
 | |
|     AVRational avg_frame_rate;
 | |
| 
 | |
|     /**
 | |
|      * For streams with AV_DISPOSITION_ATTACHED_PIC disposition, this packet
 | |
|      * will contain the attached picture.
 | |
|      *
 | |
|      * decoding: set by libavformat, must not be modified by the caller.
 | |
|      * encoding: unused
 | |
|      */
 | |
|     AVPacket attached_pic;
 | |
| 
 | |
|     /*****************************************************************
 | |
|      * All fields below this line are not part of the public API. They
 | |
|      * may not be used outside of libavformat and can be changed and
 | |
|      * removed at will.
 | |
|      * New public fields should be added right above.
 | |
|      *****************************************************************
 | |
|      */
 | |
| 
 | |
|     /**
 | |
|      * Stream information used internally by av_find_stream_info()
 | |
|      */
 | |
| #define MAX_STD_TIMEBASES (60*12+6)
 | |
|     struct {
 | |
|         int64_t last_dts;
 | |
|         int64_t duration_gcd;
 | |
|         int duration_count;
 | |
|         double (*duration_error)[2][MAX_STD_TIMEBASES];
 | |
|         int64_t codec_info_duration;
 | |
|         int64_t codec_info_duration_fields;
 | |
|         int found_decoder;
 | |
| 
 | |
|         int64_t last_duration;
 | |
| 
 | |
|         /**
 | |
|          * Those are used for average framerate estimation.
 | |
|          */
 | |
|         int64_t fps_first_dts;
 | |
|         int     fps_first_dts_idx;
 | |
|         int64_t fps_last_dts;
 | |
|         int     fps_last_dts_idx;
 | |
| 
 | |
|     } *info;
 | |
| 
 | |
|     int pts_wrap_bits; /**< number of bits in pts (used for wrapping control) */
 | |
| 
 | |
|     // Timestamp generation support:
 | |
|     /**
 | |
|      * Timestamp corresponding to the last dts sync point.
 | |
|      *
 | |
|      * Initialized when AVCodecParserContext.dts_sync_point >= 0 and
 | |
|      * a DTS is received from the underlying container. Otherwise set to
 | |
|      * AV_NOPTS_VALUE by default.
 | |
|      */
 | |
|     int64_t reference_dts;
 | |
|     int64_t first_dts;
 | |
|     int64_t cur_dts;
 | |
|     int64_t last_IP_pts;
 | |
|     int last_IP_duration;
 | |
| 
 | |
|     /**
 | |
|      * Number of packets to buffer for codec probing
 | |
|      */
 | |
| #define MAX_PROBE_PACKETS 2500
 | |
|     int probe_packets;
 | |
| 
 | |
|     /**
 | |
|      * Number of frames that have been demuxed during av_find_stream_info()
 | |
|      */
 | |
|     int codec_info_nb_frames;
 | |
| 
 | |
|     /* av_read_frame() support */
 | |
|     enum AVStreamParseType need_parsing;
 | |
|     struct AVCodecParserContext *parser;
 | |
| 
 | |
|     /**
 | |
|      * last packet in packet_buffer for this stream when muxing.
 | |
|      */
 | |
|     struct AVPacketList *last_in_packet_buffer;
 | |
|     AVProbeData probe_data;
 | |
| #define MAX_REORDER_DELAY 16
 | |
|     int64_t pts_buffer[MAX_REORDER_DELAY+1];
 | |
| 
 | |
|     AVIndexEntry *index_entries; /**< Only used if the format does not
 | |
|                                     support seeking natively. */
 | |
|     int nb_index_entries;
 | |
|     unsigned int index_entries_allocated_size;
 | |
| 
 | |
|     /**
 | |
|      * Real base framerate of the stream.
 | |
|      * This is the lowest framerate with which all timestamps can be
 | |
|      * represented accurately (it is the least common multiple of all
 | |
|      * framerates in the stream). Note, this value is just a guess!
 | |
|      * For example, if the time base is 1/90000 and all frames have either
 | |
|      * approximately 3600 or 1800 timer ticks, then r_frame_rate will be 50/1.
 | |
|      *
 | |
|      * Code outside avformat should access this field using:
 | |
|      * av_stream_get/set_r_frame_rate(stream)
 | |
|      */
 | |
|     AVRational r_frame_rate;
 | |
| 
 | |
|     /**
 | |
|      * Stream Identifier
 | |
|      * This is the MPEG-TS stream identifier +1
 | |
|      * 0 means unknown
 | |
|      */
 | |
|     int stream_identifier;
 | |
| 
 | |
|     int64_t interleaver_chunk_size;
 | |
|     int64_t interleaver_chunk_duration;
 | |
| 
 | |
|     /**
 | |
|      * stream probing state
 | |
|      * -1   -> probing finished
 | |
|      *  0   -> no probing requested
 | |
|      * rest -> perform probing with request_probe being the minimum score to accept.
 | |
|      * NOT PART OF PUBLIC API
 | |
|      */
 | |
|     int request_probe;
 | |
|     /**
 | |
|      * Indicates that everything up to the next keyframe
 | |
|      * should be discarded.
 | |
|      */
 | |
|     int skip_to_keyframe;
 | |
| 
 | |
|     /**
 | |
|      * Number of samples to skip at the start of the frame decoded from the next packet.
 | |
|      */
 | |
|     int skip_samples;
 | |
| 
 | |
|     /**
 | |
|      * Number of internally decoded frames, used internally in libavformat, do not access
 | |
|      * its lifetime differs from info which is why it is not in that structure.
 | |
|      */
 | |
|     int nb_decoded_frames;
 | |
| 
 | |
|     /**
 | |
|      * Timestamp offset added to timestamps before muxing
 | |
|      * NOT PART OF PUBLIC API
 | |
|      */
 | |
|     int64_t mux_ts_offset;
 | |
| 
 | |
|     /**
 | |
|      * Internal data to check for wrapping of the time stamp
 | |
|      */
 | |
|     int64_t pts_wrap_reference;
 | |
| 
 | |
|     /**
 | |
|      * Options for behavior, when a wrap is detected.
 | |
|      *
 | |
|      * Defined by AV_PTS_WRAP_ values.
 | |
|      *
 | |
|      * If correction is enabled, there are two possibilities:
 | |
|      * If the first time stamp is near the wrap point, the wrap offset
 | |
|      * will be subtracted, which will create negative time stamps.
 | |
|      * Otherwise the offset will be added.
 | |
|      */
 | |
|     int pts_wrap_behavior;
 | |
| 
 | |
| } AVStream;
 | |
| 
 | |
| AVRational av_stream_get_r_frame_rate(const AVStream *s);
 | |
| void       av_stream_set_r_frame_rate(AVStream *s, AVRational r);
 | |
| 
 | |
| #define AV_PROGRAM_RUNNING 1
 | |
| 
 | |
| /**
 | |
|  * New fields can be added to the end with minor version bumps.
 | |
|  * Removal, reordering and changes to existing fields require a major
 | |
|  * version bump.
 | |
|  * sizeof(AVProgram) must not be used outside libav*.
 | |
|  */
 | |
| typedef struct AVProgram {
 | |
|     int            id;
 | |
|     int            flags;
 | |
|     enum AVDiscard discard;        ///< selects which program to discard and which to feed to the caller
 | |
|     unsigned int   *stream_index;
 | |
|     unsigned int   nb_stream_indexes;
 | |
|     AVDictionary *metadata;
 | |
| 
 | |
|     int program_num;
 | |
|     int pmt_pid;
 | |
|     int pcr_pid;
 | |
| 
 | |
|     /*****************************************************************
 | |
|      * All fields below this line are not part of the public API. They
 | |
|      * may not be used outside of libavformat and can be changed and
 | |
|      * removed at will.
 | |
|      * New public fields should be added right above.
 | |
|      *****************************************************************
 | |
|      */
 | |
|     int64_t start_time;
 | |
|     int64_t end_time;
 | |
| 
 | |
|     int64_t pts_wrap_reference;    ///< reference dts for wrap detection
 | |
|     int pts_wrap_behavior;         ///< behavior on wrap detection
 | |
| } AVProgram;
 | |
| 
 | |
| #define AVFMTCTX_NOHEADER      0x0001 /**< signal that no header is present
 | |
|                                          (streams are added dynamically) */
 | |
| 
 | |
| typedef struct AVChapter {
 | |
|     int id;                 ///< unique ID to identify the chapter
 | |
|     AVRational time_base;   ///< time base in which the start/end timestamps are specified
 | |
|     int64_t start, end;     ///< chapter start/end time in time_base units
 | |
|     AVDictionary *metadata;
 | |
| } AVChapter;
 | |
| 
 | |
| 
 | |
| /**
 | |
|  * The duration of a video can be estimated through various ways, and this enum can be used
 | |
|  * to know how the duration was estimated.
 | |
|  */
 | |
| enum AVDurationEstimationMethod {
 | |
|     AVFMT_DURATION_FROM_PTS,    ///< Duration accurately estimated from PTSes
 | |
|     AVFMT_DURATION_FROM_STREAM, ///< Duration estimated from a stream with a known duration
 | |
|     AVFMT_DURATION_FROM_BITRATE ///< Duration estimated from bitrate (less accurate)
 | |
| };
 | |
| 
 | |
| /**
 | |
|  * Format I/O context.
 | |
|  * New fields can be added to the end with minor version bumps.
 | |
|  * Removal, reordering and changes to existing fields require a major
 | |
|  * version bump.
 | |
|  * sizeof(AVFormatContext) must not be used outside libav*, use
 | |
|  * avformat_alloc_context() to create an AVFormatContext.
 | |
|  */
 | |
| typedef struct AVFormatContext {
 | |
|     /**
 | |
|      * A class for logging and AVOptions. Set by avformat_alloc_context().
 | |
|      * Exports (de)muxer private options if they exist.
 | |
|      */
 | |
|     const AVClass *av_class;
 | |
| 
 | |
|     /**
 | |
|      * Can only be iformat or oformat, not both at the same time.
 | |
|      *
 | |
|      * decoding: set by avformat_open_input().
 | |
|      * encoding: set by the user.
 | |
|      */
 | |
|     struct AVInputFormat *iformat;
 | |
|     struct AVOutputFormat *oformat;
 | |
| 
 | |
|     /**
 | |
|      * Format private data. This is an AVOptions-enabled struct
 | |
|      * if and only if iformat/oformat.priv_class is not NULL.
 | |
|      */
 | |
|     void *priv_data;
 | |
| 
 | |
|     /**
 | |
|      * I/O context.
 | |
|      *
 | |
|      * decoding: either set by the user before avformat_open_input() (then
 | |
|      * the user must close it manually) or set by avformat_open_input().
 | |
|      * encoding: set by the user.
 | |
|      *
 | |
|      * Do NOT set this field if AVFMT_NOFILE flag is set in
 | |
|      * iformat/oformat.flags. In such a case, the (de)muxer will handle
 | |
|      * I/O in some other way and this field will be NULL.
 | |
|      */
 | |
|     AVIOContext *pb;
 | |
| 
 | |
|     /* stream info */
 | |
|     int ctx_flags; /**< Format-specific flags, see AVFMTCTX_xx */
 | |
| 
 | |
|     /**
 | |
|      * A list of all streams in the file. New streams are created with
 | |
|      * avformat_new_stream().
 | |
|      *
 | |
|      * decoding: streams are created by libavformat in avformat_open_input().
 | |
|      * If AVFMTCTX_NOHEADER is set in ctx_flags, then new streams may also
 | |
|      * appear in av_read_frame().
 | |
|      * encoding: streams are created by the user before avformat_write_header().
 | |
|      */
 | |
|     unsigned int nb_streams;
 | |
|     AVStream **streams;
 | |
| 
 | |
|     char filename[1024]; /**< input or output filename */
 | |
| 
 | |
|     /**
 | |
|      * Decoding: position of the first frame of the component, in
 | |
|      * AV_TIME_BASE fractional seconds. NEVER set this value directly:
 | |
|      * It is deduced from the AVStream values.
 | |
|      */
 | |
|     int64_t start_time;
 | |
| 
 | |
|     /**
 | |
|      * Decoding: duration of the stream, in AV_TIME_BASE fractional
 | |
|      * seconds. Only set this value if you know none of the individual stream
 | |
|      * durations and also do not set any of them. This is deduced from the
 | |
|      * AVStream values if not set.
 | |
|      */
 | |
|     int64_t duration;
 | |
| 
 | |
|     /**
 | |
|      * Decoding: total stream bitrate in bit/s, 0 if not
 | |
|      * available. Never set it directly if the file_size and the
 | |
|      * duration are known as FFmpeg can compute it automatically.
 | |
|      */
 | |
|     int bit_rate;
 | |
| 
 | |
|     unsigned int packet_size;
 | |
|     int max_delay;
 | |
| 
 | |
|     int flags;
 | |
| #define AVFMT_FLAG_GENPTS       0x0001 ///< Generate missing pts even if it requires parsing future frames.
 | |
| #define AVFMT_FLAG_IGNIDX       0x0002 ///< Ignore index.
 | |
| #define AVFMT_FLAG_NONBLOCK     0x0004 ///< Do not block when reading packets from input.
 | |
| #define AVFMT_FLAG_IGNDTS       0x0008 ///< Ignore DTS on frames that contain both DTS & PTS
 | |
| #define AVFMT_FLAG_NOFILLIN     0x0010 ///< Do not infer any values from other values, just return what is stored in the container
 | |
| #define AVFMT_FLAG_NOPARSE      0x0020 ///< Do not use AVParsers, you also must set AVFMT_FLAG_NOFILLIN as the fillin code works on frames and no parsing -> no frames. Also seeking to frames can not work if parsing to find frame boundaries has been disabled
 | |
| #define AVFMT_FLAG_NOBUFFER     0x0040 ///< Do not buffer frames when possible
 | |
| #define AVFMT_FLAG_CUSTOM_IO    0x0080 ///< The caller has supplied a custom AVIOContext, don't avio_close() it.
 | |
| #define AVFMT_FLAG_DISCARD_CORRUPT  0x0100 ///< Discard frames marked corrupted
 | |
| #define AVFMT_FLAG_MP4A_LATM    0x8000 ///< Enable RTP MP4A-LATM payload
 | |
| #define AVFMT_FLAG_SORT_DTS    0x10000 ///< try to interleave outputted packets by dts (using this flag can slow demuxing down)
 | |
| #define AVFMT_FLAG_PRIV_OPT    0x20000 ///< Enable use of private options by delaying codec open (this could be made default once all code is converted)
 | |
| #define AVFMT_FLAG_KEEP_SIDE_DATA 0x40000 ///< Don't merge side data but keep it separate.
 | |
| 
 | |
|     /**
 | |
|      * decoding: size of data to probe; encoding: unused.
 | |
|      */
 | |
|     unsigned int probesize;
 | |
| 
 | |
|     /**
 | |
|      * decoding: maximum time (in AV_TIME_BASE units) during which the input should
 | |
|      * be analyzed in avformat_find_stream_info().
 | |
|      */
 | |
|     int max_analyze_duration;
 | |
| 
 | |
|     const uint8_t *key;
 | |
|     int keylen;
 | |
| 
 | |
|     unsigned int nb_programs;
 | |
|     AVProgram **programs;
 | |
| 
 | |
|     /**
 | |
|      * Forced video codec_id.
 | |
|      * Demuxing: Set by user.
 | |
|      */
 | |
|     enum AVCodecID video_codec_id;
 | |
| 
 | |
|     /**
 | |
|      * Forced audio codec_id.
 | |
|      * Demuxing: Set by user.
 | |
|      */
 | |
|     enum AVCodecID audio_codec_id;
 | |
| 
 | |
|     /**
 | |
|      * Forced subtitle codec_id.
 | |
|      * Demuxing: Set by user.
 | |
|      */
 | |
|     enum AVCodecID subtitle_codec_id;
 | |
| 
 | |
|     /**
 | |
|      * Maximum amount of memory in bytes to use for the index of each stream.
 | |
|      * If the index exceeds this size, entries will be discarded as
 | |
|      * needed to maintain a smaller size. This can lead to slower or less
 | |
|      * accurate seeking (depends on demuxer).
 | |
|      * Demuxers for which a full in-memory index is mandatory will ignore
 | |
|      * this.
 | |
|      * muxing  : unused
 | |
|      * demuxing: set by user
 | |
|      */
 | |
|     unsigned int max_index_size;
 | |
| 
 | |
|     /**
 | |
|      * Maximum amount of memory in bytes to use for buffering frames
 | |
|      * obtained from realtime capture devices.
 | |
|      */
 | |
|     unsigned int max_picture_buffer;
 | |
| 
 | |
|     unsigned int nb_chapters;
 | |
|     AVChapter **chapters;
 | |
| 
 | |
|     AVDictionary *metadata;
 | |
| 
 | |
|     /**
 | |
|      * Start time of the stream in real world time, in microseconds
 | |
|      * since the unix epoch (00:00 1st January 1970). That is, pts=0
 | |
|      * in the stream was captured at this real world time.
 | |
|      * - encoding: Set by user.
 | |
|      * - decoding: Unused.
 | |
|      */
 | |
|     int64_t start_time_realtime;
 | |
| 
 | |
|     /**
 | |
|      * decoding: number of frames used to probe fps
 | |
|      */
 | |
|     int fps_probe_size;
 | |
| 
 | |
|     /**
 | |
|      * Error recognition; higher values will detect more errors but may
 | |
|      * misdetect some more or less valid parts as errors.
 | |
|      * - encoding: unused
 | |
|      * - decoding: Set by user.
 | |
|      */
 | |
|     int error_recognition;
 | |
| 
 | |
|     /**
 | |
|      * Custom interrupt callbacks for the I/O layer.
 | |
|      *
 | |
|      * decoding: set by the user before avformat_open_input().
 | |
|      * encoding: set by the user before avformat_write_header()
 | |
|      * (mainly useful for AVFMT_NOFILE formats). The callback
 | |
|      * should also be passed to avio_open2() if it's used to
 | |
|      * open the file.
 | |
|      */
 | |
|     AVIOInterruptCB interrupt_callback;
 | |
| 
 | |
|     /**
 | |
|      * Flags to enable debugging.
 | |
|      */
 | |
|     int debug;
 | |
| #define FF_FDEBUG_TS        0x0001
 | |
| 
 | |
|     /**
 | |
|      * Transport stream id.
 | |
|      * This will be moved into demuxer private options. Thus no API/ABI compatibility
 | |
|      */
 | |
|     int ts_id;
 | |
| 
 | |
|     /**
 | |
|      * Audio preload in microseconds.
 | |
|      * Note, not all formats support this and unpredictable things may happen if it is used when not supported.
 | |
|      * - encoding: Set by user via AVOptions (NO direct access)
 | |
|      * - decoding: unused
 | |
|      */
 | |
|     int audio_preload;
 | |
| 
 | |
|     /**
 | |
|      * Max chunk time in microseconds.
 | |
|      * Note, not all formats support this and unpredictable things may happen if it is used when not supported.
 | |
|      * - encoding: Set by user via AVOptions (NO direct access)
 | |
|      * - decoding: unused
 | |
|      */
 | |
|     int max_chunk_duration;
 | |
| 
 | |
|     /**
 | |
|      * Max chunk size in bytes
 | |
|      * Note, not all formats support this and unpredictable things may happen if it is used when not supported.
 | |
|      * - encoding: Set by user via AVOptions (NO direct access)
 | |
|      * - decoding: unused
 | |
|      */
 | |
|     int max_chunk_size;
 | |
| 
 | |
|     /**
 | |
|      * forces the use of wallclock timestamps as pts/dts of packets
 | |
|      * This has undefined results in the presence of B frames.
 | |
|      * - encoding: unused
 | |
|      * - decoding: Set by user via AVOptions (NO direct access)
 | |
|      */
 | |
|     int use_wallclock_as_timestamps;
 | |
| 
 | |
|     /**
 | |
|      * Avoid negative timestamps during muxing.
 | |
|      *  0 -> allow negative timestamps
 | |
|      *  1 -> avoid negative timestamps
 | |
|      * -1 -> choose automatically (default)
 | |
|      * Note, this only works when interleave_packet_per_dts is in use.
 | |
|      * - encoding: Set by user via AVOptions (NO direct access)
 | |
|      * - decoding: unused
 | |
|      */
 | |
|     int avoid_negative_ts;
 | |
| 
 | |
|     /**
 | |
|      * avio flags, used to force AVIO_FLAG_DIRECT.
 | |
|      * - encoding: unused
 | |
|      * - decoding: Set by user via AVOptions (NO direct access)
 | |
|      */
 | |
|     int avio_flags;
 | |
| 
 | |
|     /**
 | |
|      * The duration field can be estimated through various ways, and this field can be used
 | |
|      * to know how the duration was estimated.
 | |
|      * - encoding: unused
 | |
|      * - decoding: Read by user via AVOptions (NO direct access)
 | |
|      */
 | |
|     enum AVDurationEstimationMethod duration_estimation_method;
 | |
| 
 | |
|     /**
 | |
|      * Skip initial bytes when opening stream
 | |
|      * - encoding: unused
 | |
|      * - decoding: Set by user via AVOptions (NO direct access)
 | |
|      */
 | |
|     unsigned int skip_initial_bytes;
 | |
| 
 | |
|     /**
 | |
|      * Correct single timestamp overflows
 | |
|      * - encoding: unused
 | |
|      * - decoding: Set by user via AVOPtions (NO direct access)
 | |
|      */
 | |
|     unsigned int correct_ts_overflow;
 | |
| 
 | |
|     /**
 | |
|      * Force seeking to any (also non key) frames.
 | |
|      * - encoding: unused
 | |
|      * - decoding: Set by user via AVOPtions (NO direct access)
 | |
|      */
 | |
|     int seek2any;
 | |
| 
 | |
|     /**
 | |
|      * Flush the I/O context after each packet.
 | |
|      * - encoding: Set by user via AVOptions (NO direct access)
 | |
|      * - decoding: unused
 | |
|      */
 | |
|     int flush_packets;
 | |
| 
 | |
|     /*****************************************************************
 | |
|      * All fields below this line are not part of the public API. They
 | |
|      * may not be used outside of libavformat and can be changed and
 | |
|      * removed at will.
 | |
|      * New public fields should be added right above.
 | |
|      *****************************************************************
 | |
|      */
 | |
| 
 | |
|     /**
 | |
|      * This buffer is only needed when packets were already buffered but
 | |
|      * not decoded, for example to get the codec parameters in MPEG
 | |
|      * streams.
 | |
|      */
 | |
|     struct AVPacketList *packet_buffer;
 | |
|     struct AVPacketList *packet_buffer_end;
 | |
| 
 | |
|     /* av_seek_frame() support */
 | |
|     int64_t data_offset; /**< offset of the first packet */
 | |
| 
 | |
|     /**
 | |
|      * Raw packets from the demuxer, prior to parsing and decoding.
 | |
|      * This buffer is used for buffering packets until the codec can
 | |
|      * be identified, as parsing cannot be done without knowing the
 | |
|      * codec.
 | |
|      */
 | |
|     struct AVPacketList *raw_packet_buffer;
 | |
|     struct AVPacketList *raw_packet_buffer_end;
 | |
|     /**
 | |
|      * Packets split by the parser get queued here.
 | |
|      */
 | |
|     struct AVPacketList *parse_queue;
 | |
|     struct AVPacketList *parse_queue_end;
 | |
|     /**
 | |
|      * Remaining size available for raw_packet_buffer, in bytes.
 | |
|      */
 | |
| #define RAW_PACKET_BUFFER_SIZE 2500000
 | |
|     int raw_packet_buffer_remaining_size;
 | |
| 
 | |
|     /**
 | |
|      * Offset to remap timestamps to be non-negative.
 | |
|      * Expressed in timebase units.
 | |
|      * @see AVStream.mux_ts_offset
 | |
|      */
 | |
|     int64_t offset;
 | |
| 
 | |
|     /**
 | |
|      * Timebase for the timestamp offset.
 | |
|      */
 | |
|     AVRational offset_timebase;
 | |
| 
 | |
|     /**
 | |
|      * IO repositioned flag.
 | |
|      * This is set by avformat when the underlaying IO context read pointer
 | |
|      * is repositioned, for example when doing byte based seeking.
 | |
|      * Demuxers can use the flag to detect such changes.
 | |
|      */
 | |
|     int io_repositioned;
 | |
| } AVFormatContext;
 | |
| 
 | |
| /**
 | |
|  * Returns the method used to set ctx->duration.
 | |
|  *
 | |
|  * @return AVFMT_DURATION_FROM_PTS, AVFMT_DURATION_FROM_STREAM, or AVFMT_DURATION_FROM_BITRATE.
 | |
|  */
 | |
| enum AVDurationEstimationMethod av_fmt_ctx_get_duration_estimation_method(const AVFormatContext* ctx);
 | |
| 
 | |
| typedef struct AVPacketList {
 | |
|     AVPacket pkt;
 | |
|     struct AVPacketList *next;
 | |
| } AVPacketList;
 | |
| 
 | |
| 
 | |
| /**
 | |
|  * @defgroup lavf_core Core functions
 | |
|  * @ingroup libavf
 | |
|  *
 | |
|  * Functions for querying libavformat capabilities, allocating core structures,
 | |
|  * etc.
 | |
|  * @{
 | |
|  */
 | |
| 
 | |
| /**
 | |
|  * Return the LIBAVFORMAT_VERSION_INT constant.
 | |
|  */
 | |
| unsigned avformat_version(void);
 | |
| 
 | |
| /**
 | |
|  * Return the libavformat build-time configuration.
 | |
|  */
 | |
| const char *avformat_configuration(void);
 | |
| 
 | |
| /**
 | |
|  * Return the libavformat license.
 | |
|  */
 | |
| const char *avformat_license(void);
 | |
| 
 | |
| /**
 | |
|  * Initialize libavformat and register all the muxers, demuxers and
 | |
|  * protocols. If you do not call this function, then you can select
 | |
|  * exactly which formats you want to support.
 | |
|  *
 | |
|  * @see av_register_input_format()
 | |
|  * @see av_register_output_format()
 | |
|  */
 | |
| void av_register_all(void);
 | |
| 
 | |
| void av_register_input_format(AVInputFormat *format);
 | |
| void av_register_output_format(AVOutputFormat *format);
 | |
| 
 | |
| /**
 | |
|  * Do global initialization of network components. This is optional,
 | |
|  * but recommended, since it avoids the overhead of implicitly
 | |
|  * doing the setup for each session.
 | |
|  *
 | |
|  * Calling this function will become mandatory if using network
 | |
|  * protocols at some major version bump.
 | |
|  */
 | |
| int avformat_network_init(void);
 | |
| 
 | |
| /**
 | |
|  * Undo the initialization done by avformat_network_init.
 | |
|  */
 | |
| int avformat_network_deinit(void);
 | |
| 
 | |
| /**
 | |
|  * If f is NULL, returns the first registered input format,
 | |
|  * if f is non-NULL, returns the next registered input format after f
 | |
|  * or NULL if f is the last one.
 | |
|  */
 | |
| AVInputFormat  *av_iformat_next(AVInputFormat  *f);
 | |
| 
 | |
| /**
 | |
|  * If f is NULL, returns the first registered output format,
 | |
|  * if f is non-NULL, returns the next registered output format after f
 | |
|  * or NULL if f is the last one.
 | |
|  */
 | |
| AVOutputFormat *av_oformat_next(AVOutputFormat *f);
 | |
| 
 | |
| /**
 | |
|  * Allocate an AVFormatContext.
 | |
|  * avformat_free_context() can be used to free the context and everything
 | |
|  * allocated by the framework within it.
 | |
|  */
 | |
| AVFormatContext *avformat_alloc_context(void);
 | |
| 
 | |
| /**
 | |
|  * Free an AVFormatContext and all its streams.
 | |
|  * @param s context to free
 | |
|  */
 | |
| void avformat_free_context(AVFormatContext *s);
 | |
| 
 | |
| /**
 | |
|  * Get the AVClass for AVFormatContext. It can be used in combination with
 | |
|  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
 | |
|  *
 | |
|  * @see av_opt_find().
 | |
|  */
 | |
| const AVClass *avformat_get_class(void);
 | |
| 
 | |
| /**
 | |
|  * Add a new stream to a media file.
 | |
|  *
 | |
|  * When demuxing, it is called by the demuxer in read_header(). If the
 | |
|  * flag AVFMTCTX_NOHEADER is set in s.ctx_flags, then it may also
 | |
|  * be called in read_packet().
 | |
|  *
 | |
|  * When muxing, should be called by the user before avformat_write_header().
 | |
|  *
 | |
|  * @param c If non-NULL, the AVCodecContext corresponding to the new stream
 | |
|  * will be initialized to use this codec. This is needed for e.g. codec-specific
 | |
|  * defaults to be set, so codec should be provided if it is known.
 | |
|  *
 | |
|  * @return newly created stream or NULL on error.
 | |
|  */
 | |
| AVStream *avformat_new_stream(AVFormatContext *s, const AVCodec *c);
 | |
| 
 | |
| AVProgram *av_new_program(AVFormatContext *s, int id);
 | |
| 
 | |
| /**
 | |
|  * @}
 | |
|  */
 | |
| 
 | |
| 
 | |
| #if FF_API_PKT_DUMP
 | |
| attribute_deprecated void av_pkt_dump(FILE *f, AVPacket *pkt, int dump_payload);
 | |
| attribute_deprecated void av_pkt_dump_log(void *avcl, int level, AVPacket *pkt,
 | |
|                                           int dump_payload);
 | |
| #endif
 | |
| 
 | |
| #if FF_API_ALLOC_OUTPUT_CONTEXT
 | |
| /**
 | |
|  * @deprecated deprecated in favor of avformat_alloc_output_context2()
 | |
|  */
 | |
| attribute_deprecated
 | |
| AVFormatContext *avformat_alloc_output_context(const char *format,
 | |
|                                                AVOutputFormat *oformat,
 | |
|                                                const char *filename);
 | |
| #endif
 | |
| 
 | |
| /**
 | |
|  * Allocate an AVFormatContext for an output format.
 | |
|  * avformat_free_context() can be used to free the context and
 | |
|  * everything allocated by the framework within it.
 | |
|  *
 | |
|  * @param *ctx is set to the created format context, or to NULL in
 | |
|  * case of failure
 | |
|  * @param oformat format to use for allocating the context, if NULL
 | |
|  * format_name and filename are used instead
 | |
|  * @param format_name the name of output format to use for allocating the
 | |
|  * context, if NULL filename is used instead
 | |
|  * @param filename the name of the filename to use for allocating the
 | |
|  * context, may be NULL
 | |
|  * @return >= 0 in case of success, a negative AVERROR code in case of
 | |
|  * failure
 | |
|  */
 | |
| int avformat_alloc_output_context2(AVFormatContext **ctx, AVOutputFormat *oformat,
 | |
|                                    const char *format_name, const char *filename);
 | |
| 
 | |
| /**
 | |
|  * @addtogroup lavf_decoding
 | |
|  * @{
 | |
|  */
 | |
| 
 | |
| /**
 | |
|  * Find AVInputFormat based on the short name of the input format.
 | |
|  */
 | |
| AVInputFormat *av_find_input_format(const char *short_name);
 | |
| 
 | |
| /**
 | |
|  * Guess the file format.
 | |
|  *
 | |
|  * @param is_opened Whether the file is already opened; determines whether
 | |
|  *                  demuxers with or without AVFMT_NOFILE are probed.
 | |
|  */
 | |
| AVInputFormat *av_probe_input_format(AVProbeData *pd, int is_opened);
 | |
| 
 | |
| /**
 | |
|  * Guess the file format.
 | |
|  *
 | |
|  * @param is_opened Whether the file is already opened; determines whether
 | |
|  *                  demuxers with or without AVFMT_NOFILE are probed.
 | |
|  * @param score_max A probe score larger that this is required to accept a
 | |
|  *                  detection, the variable is set to the actual detection
 | |
|  *                  score afterwards.
 | |
|  *                  If the score is <= AVPROBE_SCORE_MAX / 4 it is recommended
 | |
|  *                  to retry with a larger probe buffer.
 | |
|  */
 | |
| AVInputFormat *av_probe_input_format2(AVProbeData *pd, int is_opened, int *score_max);
 | |
| 
 | |
| /**
 | |
|  * Guess the file format.
 | |
|  *
 | |
|  * @param is_opened Whether the file is already opened; determines whether
 | |
|  *                  demuxers with or without AVFMT_NOFILE are probed.
 | |
|  * @param score_ret The score of the best detection.
 | |
|  */
 | |
| AVInputFormat *av_probe_input_format3(AVProbeData *pd, int is_opened, int *score_ret);
 | |
| 
 | |
| /**
 | |
|  * Probe a bytestream to determine the input format. Each time a probe returns
 | |
|  * with a score that is too low, the probe buffer size is increased and another
 | |
|  * attempt is made. When the maximum probe size is reached, the input format
 | |
|  * with the highest score is returned.
 | |
|  *
 | |
|  * @param pb the bytestream to probe
 | |
|  * @param fmt the input format is put here
 | |
|  * @param filename the filename of the stream
 | |
|  * @param logctx the log context
 | |
|  * @param offset the offset within the bytestream to probe from
 | |
|  * @param max_probe_size the maximum probe buffer size (zero for default)
 | |
|  * @return 0 in case of success, a negative value corresponding to an
 | |
|  * AVERROR code otherwise
 | |
|  */
 | |
| int av_probe_input_buffer(AVIOContext *pb, AVInputFormat **fmt,
 | |
|                           const char *filename, void *logctx,
 | |
|                           unsigned int offset, unsigned int max_probe_size);
 | |
| 
 | |
| /**
 | |
|  * Open an input stream and read the header. The codecs are not opened.
 | |
|  * The stream must be closed with av_close_input_file().
 | |
|  *
 | |
|  * @param ps Pointer to user-supplied AVFormatContext (allocated by avformat_alloc_context).
 | |
|  *           May be a pointer to NULL, in which case an AVFormatContext is allocated by this
 | |
|  *           function and written into ps.
 | |
|  *           Note that a user-supplied AVFormatContext will be freed on failure.
 | |
|  * @param filename Name of the stream to open.
 | |
|  * @param fmt If non-NULL, this parameter forces a specific input format.
 | |
|  *            Otherwise the format is autodetected.
 | |
|  * @param options  A dictionary filled with AVFormatContext and demuxer-private options.
 | |
|  *                 On return this parameter will be destroyed and replaced with a dict containing
 | |
|  *                 options that were not found. May be NULL.
 | |
|  *
 | |
|  * @return 0 on success, a negative AVERROR on failure.
 | |
|  *
 | |
|  * @note If you want to use custom IO, preallocate the format context and set its pb field.
 | |
|  */
 | |
| int avformat_open_input(AVFormatContext **ps, const char *filename, AVInputFormat *fmt, AVDictionary **options);
 | |
| 
 | |
| attribute_deprecated
 | |
| int av_demuxer_open(AVFormatContext *ic);
 | |
| 
 | |
| #if FF_API_FORMAT_PARAMETERS
 | |
| /**
 | |
|  * Read packets of a media file to get stream information. This
 | |
|  * is useful for file formats with no headers such as MPEG. This
 | |
|  * function also computes the real framerate in case of MPEG-2 repeat
 | |
|  * frame mode.
 | |
|  * The logical file position is not changed by this function;
 | |
|  * examined packets may be buffered for later processing.
 | |
|  *
 | |
|  * @param ic media file handle
 | |
|  * @return >=0 if OK, AVERROR_xxx on error
 | |
|  * @todo Let the user decide somehow what information is needed so that
 | |
|  *       we do not waste time getting stuff the user does not need.
 | |
|  *
 | |
|  * @deprecated use avformat_find_stream_info.
 | |
|  */
 | |
| attribute_deprecated
 | |
| int av_find_stream_info(AVFormatContext *ic);
 | |
| #endif
 | |
| 
 | |
| /**
 | |
|  * Read packets of a media file to get stream information. This
 | |
|  * is useful for file formats with no headers such as MPEG. This
 | |
|  * function also computes the real framerate in case of MPEG-2 repeat
 | |
|  * frame mode.
 | |
|  * The logical file position is not changed by this function;
 | |
|  * examined packets may be buffered for later processing.
 | |
|  *
 | |
|  * @param ic media file handle
 | |
|  * @param options  If non-NULL, an ic.nb_streams long array of pointers to
 | |
|  *                 dictionaries, where i-th member contains options for
 | |
|  *                 codec corresponding to i-th stream.
 | |
|  *                 On return each dictionary will be filled with options that were not found.
 | |
|  * @return >=0 if OK, AVERROR_xxx on error
 | |
|  *
 | |
|  * @note this function isn't guaranteed to open all the codecs, so
 | |
|  *       options being non-empty at return is a perfectly normal behavior.
 | |
|  *
 | |
|  * @todo Let the user decide somehow what information is needed so that
 | |
|  *       we do not waste time getting stuff the user does not need.
 | |
|  */
 | |
| int avformat_find_stream_info(AVFormatContext *ic, AVDictionary **options);
 | |
| 
 | |
| /**
 | |
|  * Find the programs which belong to a given stream.
 | |
|  *
 | |
|  * @param ic    media file handle
 | |
|  * @param last  the last found program, the search will start after this
 | |
|  *              program, or from the beginning if it is NULL
 | |
|  * @param s     stream index
 | |
|  * @return the next program which belongs to s, NULL if no program is found or
 | |
|  *         the last program is not among the programs of ic.
 | |
|  */
 | |
| AVProgram *av_find_program_from_stream(AVFormatContext *ic, AVProgram *last, int s);
 | |
| 
 | |
| /**
 | |
|  * Find the "best" stream in the file.
 | |
|  * The best stream is determined according to various heuristics as the most
 | |
|  * likely to be what the user expects.
 | |
|  * If the decoder parameter is non-NULL, av_find_best_stream will find the
 | |
|  * default decoder for the stream's codec; streams for which no decoder can
 | |
|  * be found are ignored.
 | |
|  *
 | |
|  * @param ic                media file handle
 | |
|  * @param type              stream type: video, audio, subtitles, etc.
 | |
|  * @param wanted_stream_nb  user-requested stream number,
 | |
|  *                          or -1 for automatic selection
 | |
|  * @param related_stream    try to find a stream related (eg. in the same
 | |
|  *                          program) to this one, or -1 if none
 | |
|  * @param decoder_ret       if non-NULL, returns the decoder for the
 | |
|  *                          selected stream
 | |
|  * @param flags             flags; none are currently defined
 | |
|  * @return  the non-negative stream number in case of success,
 | |
|  *          AVERROR_STREAM_NOT_FOUND if no stream with the requested type
 | |
|  *          could be found,
 | |
|  *          AVERROR_DECODER_NOT_FOUND if streams were found but no decoder
 | |
|  * @note  If av_find_best_stream returns successfully and decoder_ret is not
 | |
|  *        NULL, then *decoder_ret is guaranteed to be set to a valid AVCodec.
 | |
|  */
 | |
| int av_find_best_stream(AVFormatContext *ic,
 | |
|                         enum AVMediaType type,
 | |
|                         int wanted_stream_nb,
 | |
|                         int related_stream,
 | |
|                         AVCodec **decoder_ret,
 | |
|                         int flags);
 | |
| 
 | |
| #if FF_API_READ_PACKET
 | |
| /**
 | |
|  * @deprecated use AVFMT_FLAG_NOFILLIN | AVFMT_FLAG_NOPARSE to read raw
 | |
|  * unprocessed packets
 | |
|  *
 | |
|  * Read a transport packet from a media file.
 | |
|  *
 | |
|  * This function is obsolete and should never be used.
 | |
|  * Use av_read_frame() instead.
 | |
|  *
 | |
|  * @param s media file handle
 | |
|  * @param pkt is filled
 | |
|  * @return 0 if OK, AVERROR_xxx on error
 | |
|  */
 | |
| attribute_deprecated
 | |
| int av_read_packet(AVFormatContext *s, AVPacket *pkt);
 | |
| #endif
 | |
| 
 | |
| /**
 | |
|  * Return the next frame of a stream.
 | |
|  * This function returns what is stored in the file, and does not validate
 | |
|  * that what is there are valid frames for the decoder. It will split what is
 | |
|  * stored in the file into frames and return one for each call. It will not
 | |
|  * omit invalid data between valid frames so as to give the decoder the maximum
 | |
|  * information possible for decoding.
 | |
|  *
 | |
|  * If pkt->buf is NULL, then the packet is valid until the next
 | |
|  * av_read_frame() or until av_close_input_file(). Otherwise the packet is valid
 | |
|  * indefinitely. In both cases the packet must be freed with
 | |
|  * av_free_packet when it is no longer needed. For video, the packet contains
 | |
|  * exactly one frame. For audio, it contains an integer number of frames if each
 | |
|  * frame has a known fixed size (e.g. PCM or ADPCM data). If the audio frames
 | |
|  * have a variable size (e.g. MPEG audio), then it contains one frame.
 | |
|  *
 | |
|  * pkt->pts, pkt->dts and pkt->duration are always set to correct
 | |
|  * values in AVStream.time_base units (and guessed if the format cannot
 | |
|  * provide them). pkt->pts can be AV_NOPTS_VALUE if the video format
 | |
|  * has B-frames, so it is better to rely on pkt->dts if you do not
 | |
|  * decompress the payload.
 | |
|  *
 | |
|  * @return 0 if OK, < 0 on error or end of file
 | |
|  */
 | |
| int av_read_frame(AVFormatContext *s, AVPacket *pkt);
 | |
| 
 | |
| /**
 | |
|  * Seek to the keyframe at timestamp.
 | |
|  * 'timestamp' in 'stream_index'.
 | |
|  * @param stream_index If stream_index is (-1), a default
 | |
|  * stream is selected, and timestamp is automatically converted
 | |
|  * from AV_TIME_BASE units to the stream specific time_base.
 | |
|  * @param timestamp Timestamp in AVStream.time_base units
 | |
|  *        or, if no stream is specified, in AV_TIME_BASE units.
 | |
|  * @param flags flags which select direction and seeking mode
 | |
|  * @return >= 0 on success
 | |
|  */
 | |
| int av_seek_frame(AVFormatContext *s, int stream_index, int64_t timestamp,
 | |
|                   int flags);
 | |
| 
 | |
| /**
 | |
|  * Seek to timestamp ts.
 | |
|  * Seeking will be done so that the point from which all active streams
 | |
|  * can be presented successfully will be closest to ts and within min/max_ts.
 | |
|  * Active streams are all streams that have AVStream.discard < AVDISCARD_ALL.
 | |
|  *
 | |
|  * If flags contain AVSEEK_FLAG_BYTE, then all timestamps are in bytes and
 | |
|  * are the file position (this may not be supported by all demuxers).
 | |
|  * If flags contain AVSEEK_FLAG_FRAME, then all timestamps are in frames
 | |
|  * in the stream with stream_index (this may not be supported by all demuxers).
 | |
|  * Otherwise all timestamps are in units of the stream selected by stream_index
 | |
|  * or if stream_index is -1, in AV_TIME_BASE units.
 | |
|  * If flags contain AVSEEK_FLAG_ANY, then non-keyframes are treated as
 | |
|  * keyframes (this may not be supported by all demuxers).
 | |
|  * If flags contain AVSEEK_FLAG_BACKWARD, it is ignored.
 | |
|  *
 | |
|  * @param stream_index index of the stream which is used as time base reference
 | |
|  * @param min_ts smallest acceptable timestamp
 | |
|  * @param ts target timestamp
 | |
|  * @param max_ts largest acceptable timestamp
 | |
|  * @param flags flags
 | |
|  * @return >=0 on success, error code otherwise
 | |
|  *
 | |
|  * @note This is part of the new seek API which is still under construction.
 | |
|  *       Thus do not use this yet. It may change at any time, do not expect
 | |
|  *       ABI compatibility yet!
 | |
|  */
 | |
| int avformat_seek_file(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags);
 | |
| 
 | |
| /**
 | |
|  * Start playing a network-based stream (e.g. RTSP stream) at the
 | |
|  * current position.
 | |
|  */
 | |
| int av_read_play(AVFormatContext *s);
 | |
| 
 | |
| /**
 | |
|  * Pause a network-based stream (e.g. RTSP stream).
 | |
|  *
 | |
|  * Use av_read_play() to resume it.
 | |
|  */
 | |
| int av_read_pause(AVFormatContext *s);
 | |
| 
 | |
| #if FF_API_CLOSE_INPUT_FILE
 | |
| /**
 | |
|  * @deprecated use avformat_close_input()
 | |
|  * Close a media file (but not its codecs).
 | |
|  *
 | |
|  * @param s media file handle
 | |
|  */
 | |
| attribute_deprecated
 | |
| void av_close_input_file(AVFormatContext *s);
 | |
| #endif
 | |
| 
 | |
| /**
 | |
|  * Close an opened input AVFormatContext. Free it and all its contents
 | |
|  * and set *s to NULL.
 | |
|  */
 | |
| void avformat_close_input(AVFormatContext **s);
 | |
| /**
 | |
|  * @}
 | |
|  */
 | |
| 
 | |
| #if FF_API_NEW_STREAM
 | |
| /**
 | |
|  * Add a new stream to a media file.
 | |
|  *
 | |
|  * Can only be called in the read_header() function. If the flag
 | |
|  * AVFMTCTX_NOHEADER is in the format context, then new streams
 | |
|  * can be added in read_packet too.
 | |
|  *
 | |
|  * @param s media file handle
 | |
|  * @param id file-format-dependent stream ID
 | |
|  */
 | |
| attribute_deprecated
 | |
| AVStream *av_new_stream(AVFormatContext *s, int id);
 | |
| #endif
 | |
| 
 | |
| #if FF_API_SET_PTS_INFO
 | |
| /**
 | |
|  * @deprecated this function is not supposed to be called outside of lavf
 | |
|  */
 | |
| attribute_deprecated
 | |
| void av_set_pts_info(AVStream *s, int pts_wrap_bits,
 | |
|                      unsigned int pts_num, unsigned int pts_den);
 | |
| #endif
 | |
| 
 | |
| #define AVSEEK_FLAG_BACKWARD 1 ///< seek backward
 | |
| #define AVSEEK_FLAG_BYTE     2 ///< seeking based on position in bytes
 | |
| #define AVSEEK_FLAG_ANY      4 ///< seek to any frame, even non-keyframes
 | |
| #define AVSEEK_FLAG_FRAME    8 ///< seeking based on frame number
 | |
| 
 | |
| /**
 | |
|  * @addtogroup lavf_encoding
 | |
|  * @{
 | |
|  */
 | |
| /**
 | |
|  * Allocate the stream private data and write the stream header to
 | |
|  * an output media file.
 | |
|  *
 | |
|  * @param s Media file handle, must be allocated with avformat_alloc_context().
 | |
|  *          Its oformat field must be set to the desired output format;
 | |
|  *          Its pb field must be set to an already opened AVIOContext.
 | |
|  * @param options  An AVDictionary filled with AVFormatContext and muxer-private options.
 | |
|  *                 On return this parameter will be destroyed and replaced with a dict containing
 | |
|  *                 options that were not found. May be NULL.
 | |
|  *
 | |
|  * @return 0 on success, negative AVERROR on failure.
 | |
|  *
 | |
|  * @see av_opt_find, av_dict_set, avio_open, av_oformat_next.
 | |
|  */
 | |
| int avformat_write_header(AVFormatContext *s, AVDictionary **options);
 | |
| 
 | |
| /**
 | |
|  * Write a packet to an output media file.
 | |
|  *
 | |
|  * The packet shall contain one audio or video frame.
 | |
|  * The packet must be correctly interleaved according to the container
 | |
|  * specification, if not then av_interleaved_write_frame must be used.
 | |
|  *
 | |
|  * @param s media file handle
 | |
|  * @param pkt The packet, which contains the stream_index, buf/buf_size,
 | |
|  *            dts/pts, ...
 | |
|  *            This can be NULL (at any time, not just at the end), in
 | |
|  *            order to immediately flush data buffered within the muxer,
 | |
|  *            for muxers that buffer up data internally before writing it
 | |
|  *            to the output.
 | |
|  * @return < 0 on error, = 0 if OK, 1 if flushed and there is no more data to flush
 | |
|  */
 | |
| int av_write_frame(AVFormatContext *s, AVPacket *pkt);
 | |
| 
 | |
| /**
 | |
|  * Write a packet to an output media file ensuring correct interleaving.
 | |
|  *
 | |
|  * The packet must contain one audio or video frame.
 | |
|  * If the packets are already correctly interleaved, the application should
 | |
|  * call av_write_frame() instead as it is slightly faster. It is also important
 | |
|  * to keep in mind that completely non-interleaved input will need huge amounts
 | |
|  * of memory to interleave with this, so it is preferable to interleave at the
 | |
|  * demuxer level.
 | |
|  *
 | |
|  * @param s media file handle
 | |
|  * @param pkt The packet containing the data to be written. pkt->buf must be set
 | |
|  * to a valid AVBufferRef describing the packet data. Libavformat takes
 | |
|  * ownership of this reference and will unref it when it sees fit. The caller
 | |
|  * must not access the data through this reference after this function returns.
 | |
|  * This can be NULL (at any time, not just at the end), to flush the
 | |
|  * interleaving queues.
 | |
|  * Packet's @ref AVPacket.stream_index "stream_index" field must be set to the
 | |
|  * index of the corresponding stream in @ref AVFormatContext.streams
 | |
|  * "s.streams".
 | |
|  * It is very strongly recommended that timing information (@ref AVPacket.pts
 | |
|  * "pts", @ref AVPacket.dts "dts" @ref AVPacket.duration "duration") is set to
 | |
|  * correct values.
 | |
|  *
 | |
|  * @return 0 on success, a negative AVERROR on error.
 | |
|  */
 | |
| int av_interleaved_write_frame(AVFormatContext *s, AVPacket *pkt);
 | |
| 
 | |
| /**
 | |
|  * Write the stream trailer to an output media file and free the
 | |
|  * file private data.
 | |
|  *
 | |
|  * May only be called after a successful call to avformat_write_header.
 | |
|  *
 | |
|  * @param s media file handle
 | |
|  * @return 0 if OK, AVERROR_xxx on error
 | |
|  */
 | |
| int av_write_trailer(AVFormatContext *s);
 | |
| 
 | |
| /**
 | |
|  * Return the output format in the list of registered output formats
 | |
|  * which best matches the provided parameters, or return NULL if
 | |
|  * there is no match.
 | |
|  *
 | |
|  * @param short_name if non-NULL checks if short_name matches with the
 | |
|  * names of the registered formats
 | |
|  * @param filename if non-NULL checks if filename terminates with the
 | |
|  * extensions of the registered formats
 | |
|  * @param mime_type if non-NULL checks if mime_type matches with the
 | |
|  * MIME type of the registered formats
 | |
|  */
 | |
| AVOutputFormat *av_guess_format(const char *short_name,
 | |
|                                 const char *filename,
 | |
|                                 const char *mime_type);
 | |
| 
 | |
| /**
 | |
|  * Guess the codec ID based upon muxer and filename.
 | |
|  */
 | |
| enum AVCodecID av_guess_codec(AVOutputFormat *fmt, const char *short_name,
 | |
|                             const char *filename, const char *mime_type,
 | |
|                             enum AVMediaType type);
 | |
| 
 | |
| /**
 | |
|  * Get timing information for the data currently output.
 | |
|  * The exact meaning of "currently output" depends on the format.
 | |
|  * It is mostly relevant for devices that have an internal buffer and/or
 | |
|  * work in real time.
 | |
|  * @param s          media file handle
 | |
|  * @param stream     stream in the media file
 | |
|  * @param[out] dts   DTS of the last packet output for the stream, in stream
 | |
|  *                   time_base units
 | |
|  * @param[out] wall  absolute time when that packet whas output,
 | |
|  *                   in microsecond
 | |
|  * @return  0 if OK, AVERROR(ENOSYS) if the format does not support it
 | |
|  * Note: some formats or devices may not allow to measure dts and wall
 | |
|  * atomically.
 | |
|  */
 | |
| int av_get_output_timestamp(struct AVFormatContext *s, int stream,
 | |
|                             int64_t *dts, int64_t *wall);
 | |
| 
 | |
| 
 | |
| /**
 | |
|  * @}
 | |
|  */
 | |
| 
 | |
| 
 | |
| /**
 | |
|  * @defgroup lavf_misc Utility functions
 | |
|  * @ingroup libavf
 | |
|  * @{
 | |
|  *
 | |
|  * Miscellaneous utility functions related to both muxing and demuxing
 | |
|  * (or neither).
 | |
|  */
 | |
| 
 | |
| /**
 | |
|  * Send a nice hexadecimal dump of a buffer to the specified file stream.
 | |
|  *
 | |
|  * @param f The file stream pointer where the dump should be sent to.
 | |
|  * @param buf buffer
 | |
|  * @param size buffer size
 | |
|  *
 | |
|  * @see av_hex_dump_log, av_pkt_dump2, av_pkt_dump_log2
 | |
|  */
 | |
| void av_hex_dump(FILE *f, const uint8_t *buf, int size);
 | |
| 
 | |
| /**
 | |
|  * Send a nice hexadecimal dump of a buffer to the log.
 | |
|  *
 | |
|  * @param avcl A pointer to an arbitrary struct of which the first field is a
 | |
|  * pointer to an AVClass struct.
 | |
|  * @param level The importance level of the message, lower values signifying
 | |
|  * higher importance.
 | |
|  * @param buf buffer
 | |
|  * @param size buffer size
 | |
|  *
 | |
|  * @see av_hex_dump, av_pkt_dump2, av_pkt_dump_log2
 | |
|  */
 | |
| void av_hex_dump_log(void *avcl, int level, const uint8_t *buf, int size);
 | |
| 
 | |
| /**
 | |
|  * Send a nice dump of a packet to the specified file stream.
 | |
|  *
 | |
|  * @param f The file stream pointer where the dump should be sent to.
 | |
|  * @param pkt packet to dump
 | |
|  * @param dump_payload True if the payload must be displayed, too.
 | |
|  * @param st AVStream that the packet belongs to
 | |
|  */
 | |
| void av_pkt_dump2(FILE *f, AVPacket *pkt, int dump_payload, AVStream *st);
 | |
| 
 | |
| 
 | |
| /**
 | |
|  * Send a nice dump of a packet to the log.
 | |
|  *
 | |
|  * @param avcl A pointer to an arbitrary struct of which the first field is a
 | |
|  * pointer to an AVClass struct.
 | |
|  * @param level The importance level of the message, lower values signifying
 | |
|  * higher importance.
 | |
|  * @param pkt packet to dump
 | |
|  * @param dump_payload True if the payload must be displayed, too.
 | |
|  * @param st AVStream that the packet belongs to
 | |
|  */
 | |
| void av_pkt_dump_log2(void *avcl, int level, AVPacket *pkt, int dump_payload,
 | |
|                       AVStream *st);
 | |
| 
 | |
| /**
 | |
|  * Get the AVCodecID for the given codec tag tag.
 | |
|  * If no codec id is found returns AV_CODEC_ID_NONE.
 | |
|  *
 | |
|  * @param tags list of supported codec_id-codec_tag pairs, as stored
 | |
|  * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
 | |
|  */
 | |
| enum AVCodecID av_codec_get_id(const struct AVCodecTag * const *tags, unsigned int tag);
 | |
| 
 | |
| /**
 | |
|  * Get the codec tag for the given codec id id.
 | |
|  * If no codec tag is found returns 0.
 | |
|  *
 | |
|  * @param tags list of supported codec_id-codec_tag pairs, as stored
 | |
|  * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
 | |
|  */
 | |
| unsigned int av_codec_get_tag(const struct AVCodecTag * const *tags, enum AVCodecID id);
 | |
| 
 | |
| /**
 | |
|  * Get the codec tag for the given codec id.
 | |
|  *
 | |
|  * @param tags list of supported codec_id - codec_tag pairs, as stored
 | |
|  * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
 | |
|  * @param id codec id that should be searched for in the list
 | |
|  * @param tag A pointer to the found tag
 | |
|  * @return 0 if id was not found in tags, > 0 if it was found
 | |
|  */
 | |
| int av_codec_get_tag2(const struct AVCodecTag * const *tags, enum AVCodecID id,
 | |
|                       unsigned int *tag);
 | |
| 
 | |
| int av_find_default_stream_index(AVFormatContext *s);
 | |
| 
 | |
| /**
 | |
|  * Get the index for a specific timestamp.
 | |
|  * @param flags if AVSEEK_FLAG_BACKWARD then the returned index will correspond
 | |
|  *                 to the timestamp which is <= the requested one, if backward
 | |
|  *                 is 0, then it will be >=
 | |
|  *              if AVSEEK_FLAG_ANY seek to any frame, only keyframes otherwise
 | |
|  * @return < 0 if no such timestamp could be found
 | |
|  */
 | |
| int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags);
 | |
| 
 | |
| /**
 | |
|  * Add an index entry into a sorted list. Update the entry if the list
 | |
|  * already contains it.
 | |
|  *
 | |
|  * @param timestamp timestamp in the time base of the given stream
 | |
|  */
 | |
| int av_add_index_entry(AVStream *st, int64_t pos, int64_t timestamp,
 | |
|                        int size, int distance, int flags);
 | |
| 
 | |
| 
 | |
| /**
 | |
|  * Split a URL string into components.
 | |
|  *
 | |
|  * The pointers to buffers for storing individual components may be null,
 | |
|  * in order to ignore that component. Buffers for components not found are
 | |
|  * set to empty strings. If the port is not found, it is set to a negative
 | |
|  * value.
 | |
|  *
 | |
|  * @param proto the buffer for the protocol
 | |
|  * @param proto_size the size of the proto buffer
 | |
|  * @param authorization the buffer for the authorization
 | |
|  * @param authorization_size the size of the authorization buffer
 | |
|  * @param hostname the buffer for the host name
 | |
|  * @param hostname_size the size of the hostname buffer
 | |
|  * @param port_ptr a pointer to store the port number in
 | |
|  * @param path the buffer for the path
 | |
|  * @param path_size the size of the path buffer
 | |
|  * @param url the URL to split
 | |
|  */
 | |
| void av_url_split(char *proto,         int proto_size,
 | |
|                   char *authorization, int authorization_size,
 | |
|                   char *hostname,      int hostname_size,
 | |
|                   int *port_ptr,
 | |
|                   char *path,          int path_size,
 | |
|                   const char *url);
 | |
| 
 | |
| 
 | |
| void av_dump_format(AVFormatContext *ic,
 | |
|                     int index,
 | |
|                     const char *url,
 | |
|                     int is_output);
 | |
| 
 | |
| /**
 | |
|  * Return in 'buf' the path with '%d' replaced by a number.
 | |
|  *
 | |
|  * Also handles the '%0nd' format where 'n' is the total number
 | |
|  * of digits and '%%'.
 | |
|  *
 | |
|  * @param buf destination buffer
 | |
|  * @param buf_size destination buffer size
 | |
|  * @param path numbered sequence string
 | |
|  * @param number frame number
 | |
|  * @return 0 if OK, -1 on format error
 | |
|  */
 | |
| int av_get_frame_filename(char *buf, int buf_size,
 | |
|                           const char *path, int number);
 | |
| 
 | |
| /**
 | |
|  * Check whether filename actually is a numbered sequence generator.
 | |
|  *
 | |
|  * @param filename possible numbered sequence string
 | |
|  * @return 1 if a valid numbered sequence string, 0 otherwise
 | |
|  */
 | |
| int av_filename_number_test(const char *filename);
 | |
| 
 | |
| /**
 | |
|  * Generate an SDP for an RTP session.
 | |
|  *
 | |
|  * Note, this overwrites the id values of AVStreams in the muxer contexts
 | |
|  * for getting unique dynamic payload types.
 | |
|  *
 | |
|  * @param ac array of AVFormatContexts describing the RTP streams. If the
 | |
|  *           array is composed by only one context, such context can contain
 | |
|  *           multiple AVStreams (one AVStream per RTP stream). Otherwise,
 | |
|  *           all the contexts in the array (an AVCodecContext per RTP stream)
 | |
|  *           must contain only one AVStream.
 | |
|  * @param n_files number of AVCodecContexts contained in ac
 | |
|  * @param buf buffer where the SDP will be stored (must be allocated by
 | |
|  *            the caller)
 | |
|  * @param size the size of the buffer
 | |
|  * @return 0 if OK, AVERROR_xxx on error
 | |
|  */
 | |
| int av_sdp_create(AVFormatContext *ac[], int n_files, char *buf, int size);
 | |
| 
 | |
| /**
 | |
|  * Return a positive value if the given filename has one of the given
 | |
|  * extensions, 0 otherwise.
 | |
|  *
 | |
|  * @param extensions a comma-separated list of filename extensions
 | |
|  */
 | |
| int av_match_ext(const char *filename, const char *extensions);
 | |
| 
 | |
| /**
 | |
|  * Test if the given container can store a codec.
 | |
|  *
 | |
|  * @param std_compliance standards compliance level, one of FF_COMPLIANCE_*
 | |
|  *
 | |
|  * @return 1 if codec with ID codec_id can be stored in ofmt, 0 if it cannot.
 | |
|  *         A negative number if this information is not available.
 | |
|  */
 | |
| int avformat_query_codec(AVOutputFormat *ofmt, enum AVCodecID codec_id, int std_compliance);
 | |
| 
 | |
| /**
 | |
|  * @defgroup riff_fourcc RIFF FourCCs
 | |
|  * @{
 | |
|  * Get the tables mapping RIFF FourCCs to libavcodec AVCodecIDs. The tables are
 | |
|  * meant to be passed to av_codec_get_id()/av_codec_get_tag() as in the
 | |
|  * following code:
 | |
|  * @code
 | |
|  * uint32_t tag = MKTAG('H', '2', '6', '4');
 | |
|  * const struct AVCodecTag *table[] = { avformat_get_riff_video_tags(), 0 };
 | |
|  * enum AVCodecID id = av_codec_get_id(table, tag);
 | |
|  * @endcode
 | |
|  */
 | |
| /**
 | |
|  * @return the table mapping RIFF FourCCs for video to libavcodec AVCodecID.
 | |
|  */
 | |
| const struct AVCodecTag *avformat_get_riff_video_tags(void);
 | |
| /**
 | |
|  * @return the table mapping RIFF FourCCs for audio to AVCodecID.
 | |
|  */
 | |
| const struct AVCodecTag *avformat_get_riff_audio_tags(void);
 | |
| 
 | |
| /**
 | |
|  * @}
 | |
|  */
 | |
| 
 | |
| /**
 | |
|  * Guess the sample aspect ratio of a frame, based on both the stream and the
 | |
|  * frame aspect ratio.
 | |
|  *
 | |
|  * Since the frame aspect ratio is set by the codec but the stream aspect ratio
 | |
|  * is set by the demuxer, these two may not be equal. This function tries to
 | |
|  * return the value that you should use if you would like to display the frame.
 | |
|  *
 | |
|  * Basic logic is to use the stream aspect ratio if it is set to something sane
 | |
|  * otherwise use the frame aspect ratio. This way a container setting, which is
 | |
|  * usually easy to modify can override the coded value in the frames.
 | |
|  *
 | |
|  * @param format the format context which the stream is part of
 | |
|  * @param stream the stream which the frame is part of
 | |
|  * @param frame the frame with the aspect ratio to be determined
 | |
|  * @return the guessed (valid) sample_aspect_ratio, 0/1 if no idea
 | |
|  */
 | |
| AVRational av_guess_sample_aspect_ratio(AVFormatContext *format, AVStream *stream, AVFrame *frame);
 | |
| 
 | |
| /**
 | |
|  * Guess the frame rate, based on both the container and codec information.
 | |
|  *
 | |
|  * @param ctx the format context which the stream is part of
 | |
|  * @param stream the stream which the frame is part of
 | |
|  * @param frame the frame for which the frame rate should be determined, may be NULL
 | |
|  * @return the guessed (valid) frame rate, 0/1 if no idea
 | |
|  */
 | |
| AVRational av_guess_frame_rate(AVFormatContext *ctx, AVStream *stream, AVFrame *frame);
 | |
| 
 | |
| /**
 | |
|  * Check if the stream st contained in s is matched by the stream specifier
 | |
|  * spec.
 | |
|  *
 | |
|  * See the "stream specifiers" chapter in the documentation for the syntax
 | |
|  * of spec.
 | |
|  *
 | |
|  * @return  >0 if st is matched by spec;
 | |
|  *          0  if st is not matched by spec;
 | |
|  *          AVERROR code if spec is invalid
 | |
|  *
 | |
|  * @note  A stream specifier can match several streams in the format.
 | |
|  */
 | |
| int avformat_match_stream_specifier(AVFormatContext *s, AVStream *st,
 | |
|                                     const char *spec);
 | |
| 
 | |
| int avformat_queue_attached_pictures(AVFormatContext *s);
 | |
| 
 | |
| 
 | |
| /**
 | |
|  * @}
 | |
|  */
 | |
| 
 | |
| #endif /* AVFORMAT_AVFORMAT_H */
 |