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westwood: split the AUD and VQA demuxers into separate files.

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They have no code in common.
This commit is contained in:
Justin Ruggles 2012-01-20 13:56:51 -05:00
parent 15cea3695d
commit e924a4ba71
3 changed files with 177 additions and 147 deletions
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4
libavformat/Makefile
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@ -308,8 +308,8 @@ OBJS-$(CONFIG_WC3_DEMUXER) += wc3movie.o
OBJS-$(CONFIG_WEBM_MUXER) += matroskaenc.o matroska.o \
riff.o isom.o avc.o \
flacenc_header.o avlanguage.o
OBJS-$(CONFIG_WSAUD_DEMUXER) += westwood.o
OBJS-$(CONFIG_WSVQA_DEMUXER) += westwood.o
OBJS-$(CONFIG_WSAUD_DEMUXER) += westwood_aud.o
OBJS-$(CONFIG_WSVQA_DEMUXER) += westwood_vqa.o
OBJS-$(CONFIG_WTV_DEMUXER) += wtv.o asfdec.o asf.o asfcrypt.o \
avlanguage.o mpegts.o isom.o riff.o
OBJS-$(CONFIG_WV_DEMUXER) += wv.o apetag.o

173
libavformat/westwood_aud.c Normal file
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@ -0,0 +1,173 @@
/*
* Westwood Studios AUD Format Demuxer
* Copyright (c) 2003 The ffmpeg Project
*
* This file is part of Libav.
*
* Libav is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* Libav is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* Westwood Studios AUD file demuxer
* by Mike Melanson (melanson@pcisys.net)
* for more information on the Westwood file formats, visit:
* http://www.pcisys.net/~melanson/codecs/
* http://www.geocities.com/SiliconValley/8682/aud3.txt
*
* Implementation note: There is no definite file signature for AUD files.
* The demuxer uses a probabilistic strategy for content detection. This
* entails performing sanity checks on certain header values in order to
* qualify a file. Refer to wsaud_probe() for the precise parameters.
*/
#include "libavutil/intreadwrite.h"
#include "avformat.h"
#include "internal.h"
#define AUD_HEADER_SIZE 12
#define AUD_CHUNK_PREAMBLE_SIZE 8
#define AUD_CHUNK_SIGNATURE 0x0000DEAF
typedef struct WsAudDemuxContext {
int audio_samplerate;
int audio_channels;
int audio_bits;
enum CodecID audio_type;
int audio_stream_index;
int64_t audio_frame_counter;
} WsAudDemuxContext;
static int wsaud_probe(AVProbeData *p)
{
int field;
/* Probabilistic content detection strategy: There is no file signature
* so perform sanity checks on various header parameters:
* 8000 <= sample rate (16 bits) <= 48000 ==> 40001 acceptable numbers
* flags <= 0x03 (2 LSBs are used) ==> 4 acceptable numbers
* compression type (8 bits) = 1 or 99 ==> 2 acceptable numbers
* first audio chunk signature (32 bits) ==> 1 acceptable number
* The number space contains 2^64 numbers. There are 40001 * 4 * 2 * 1 =
* 320008 acceptable number combinations.
*/
if (p->buf_size < AUD_HEADER_SIZE + AUD_CHUNK_PREAMBLE_SIZE)
return 0;
/* check sample rate */
field = AV_RL16(&p->buf[0]);
if ((field < 8000) || (field > 48000))
return 0;
/* enforce the rule that the top 6 bits of this flags field are reserved (0);
* this might not be true, but enforce it until deemed unnecessary */
if (p->buf[10] & 0xFC)
return 0;
/* note: only check for WS IMA (type 99) right now since there is no
* support for type 1 */
if (p->buf[11] != 99)
return 0;
/* read ahead to the first audio chunk and validate the first header signature */
if (AV_RL32(&p->buf[16]) != AUD_CHUNK_SIGNATURE)
return 0;
/* return 1/2 certainty since this file check is a little sketchy */
return AVPROBE_SCORE_MAX / 2;
}
static int wsaud_read_header(AVFormatContext *s,
AVFormatParameters *ap)
{
WsAudDemuxContext *wsaud = s->priv_data;
AVIOContext *pb = s->pb;
AVStream *st;
unsigned char header[AUD_HEADER_SIZE];
if (avio_read(pb, header, AUD_HEADER_SIZE) != AUD_HEADER_SIZE)
return AVERROR(EIO);
wsaud->audio_samplerate = AV_RL16(&header[0]);
if (header[11] == 99)
wsaud->audio_type = CODEC_ID_ADPCM_IMA_WS;
else
return AVERROR_INVALIDDATA;
/* flag 0 indicates stereo */
wsaud->audio_channels = (header[10] & 0x1) + 1;
/* flag 1 indicates 16 bit audio */
wsaud->audio_bits = (((header[10] & 0x2) >> 1) + 1) * 8;
/* initialize the audio decoder stream */
st = avformat_new_stream(s, NULL);
if (!st)
return AVERROR(ENOMEM);
avpriv_set_pts_info(st, 33, 1, wsaud->audio_samplerate);
st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
st->codec->codec_id = wsaud->audio_type;
st->codec->codec_tag = 0; /* no tag */
st->codec->channels = wsaud->audio_channels;
st->codec->sample_rate = wsaud->audio_samplerate;
st->codec->bits_per_coded_sample = wsaud->audio_bits;
st->codec->bit_rate = st->codec->channels * st->codec->sample_rate *
st->codec->bits_per_coded_sample / 4;
st->codec->block_align = st->codec->channels * st->codec->bits_per_coded_sample;
wsaud->audio_stream_index = st->index;
wsaud->audio_frame_counter = 0;
return 0;
}
static int wsaud_read_packet(AVFormatContext *s,
AVPacket *pkt)
{
WsAudDemuxContext *wsaud = s->priv_data;
AVIOContext *pb = s->pb;
unsigned char preamble[AUD_CHUNK_PREAMBLE_SIZE];
unsigned int chunk_size;
int ret = 0;
if (avio_read(pb, preamble, AUD_CHUNK_PREAMBLE_SIZE) !=
AUD_CHUNK_PREAMBLE_SIZE)
return AVERROR(EIO);
/* validate the chunk */
if (AV_RL32(&preamble[4]) != AUD_CHUNK_SIGNATURE)
return AVERROR_INVALIDDATA;
chunk_size = AV_RL16(&preamble[0]);
ret= av_get_packet(pb, pkt, chunk_size);
if (ret != chunk_size)
return AVERROR(EIO);
pkt->stream_index = wsaud->audio_stream_index;
pkt->pts = wsaud->audio_frame_counter;
pkt->pts /= wsaud->audio_samplerate;
/* 2 samples/byte, 1 or 2 samples per frame depending on stereo */
wsaud->audio_frame_counter += (chunk_size * 2) / wsaud->audio_channels;
return ret;
}
AVInputFormat ff_wsaud_demuxer = {
.name = "wsaud",
.long_name = NULL_IF_CONFIG_SMALL("Westwood Studios audio format"),
.priv_data_size = sizeof(WsAudDemuxContext),
.read_probe = wsaud_probe,
.read_header = wsaud_read_header,
.read_packet = wsaud_read_packet,
};

147
libavformat/westwood.c → libavformat/westwood_vqa.c
View File

@ -1,5 +1,5 @@
/*
* Westwood Studios Multimedia Formats Demuxer (VQA, AUD)
* Westwood Studios VQA Format Demuxer
* Copyright (c) 2003 The ffmpeg Project
*
* This file is part of Libav.
@ -21,26 +21,17 @@
/**
* @file
* Westwood Studios VQA & AUD file demuxers
* Westwood Studios VQA file demuxer
* by Mike Melanson (melanson@pcisys.net)
* for more information on the Westwood file formats, visit:
* http://www.pcisys.net/~melanson/codecs/
* http://www.geocities.com/SiliconValley/8682/aud3.txt
*
* Implementation note: There is no definite file signature for AUD files.
* The demuxer uses a probabilistic strategy for content detection. This
* entails performing sanity checks on certain header values in order to
* qualify a file. Refer to wsaud_probe() for the precise parameters.
*/
#include "libavutil/intreadwrite.h"
#include "avformat.h"
#include "internal.h"
#define AUD_HEADER_SIZE 12
#define AUD_CHUNK_PREAMBLE_SIZE 8
#define AUD_CHUNK_SIGNATURE 0x0000DEAF
#define FORM_TAG MKBETAG('F', 'O', 'R', 'M')
#define WVQA_TAG MKBETAG('W', 'V', 'Q', 'A')
#define VQHD_TAG MKBETAG('V', 'Q', 'H', 'D')
@ -63,15 +54,6 @@
#define VQA_FRAMERATE 15
#define VQA_PREAMBLE_SIZE 8
typedef struct WsAudDemuxContext {
int audio_samplerate;
int audio_channels;
int audio_bits;
enum CodecID audio_type;
int audio_stream_index;
int64_t audio_frame_counter;
} WsAudDemuxContext;
typedef struct WsVqaDemuxContext {
int audio_samplerate;
int audio_channels;
@ -83,119 +65,6 @@ typedef struct WsVqaDemuxContext {
int64_t audio_frame_counter;
} WsVqaDemuxContext;
static int wsaud_probe(AVProbeData *p)
{
int field;
/* Probabilistic content detection strategy: There is no file signature
* so perform sanity checks on various header parameters:
* 8000 <= sample rate (16 bits) <= 48000 ==> 40001 acceptable numbers
* flags <= 0x03 (2 LSBs are used) ==> 4 acceptable numbers
* compression type (8 bits) = 1 or 99 ==> 2 acceptable numbers
* first audio chunk signature (32 bits) ==> 1 acceptable number
* The number space contains 2^64 numbers. There are 40001 * 4 * 2 * 1 =
* 320008 acceptable number combinations.
*/
if (p->buf_size < AUD_HEADER_SIZE + AUD_CHUNK_PREAMBLE_SIZE)
return 0;
/* check sample rate */
field = AV_RL16(&p->buf[0]);
if ((field < 8000) || (field > 48000))
return 0;
/* enforce the rule that the top 6 bits of this flags field are reserved (0);
* this might not be true, but enforce it until deemed unnecessary */
if (p->buf[10] & 0xFC)
return 0;
/* note: only check for WS IMA (type 99) right now since there is no
* support for type 1 */
if (p->buf[11] != 99)
return 0;
/* read ahead to the first audio chunk and validate the first header signature */
if (AV_RL32(&p->buf[16]) != AUD_CHUNK_SIGNATURE)
return 0;
/* return 1/2 certainty since this file check is a little sketchy */
return AVPROBE_SCORE_MAX / 2;
}
static int wsaud_read_header(AVFormatContext *s,
AVFormatParameters *ap)
{
WsAudDemuxContext *wsaud = s->priv_data;
AVIOContext *pb = s->pb;
AVStream *st;
unsigned char header[AUD_HEADER_SIZE];
if (avio_read(pb, header, AUD_HEADER_SIZE) != AUD_HEADER_SIZE)
return AVERROR(EIO);
wsaud->audio_samplerate = AV_RL16(&header[0]);
if (header[11] == 99)
wsaud->audio_type = CODEC_ID_ADPCM_IMA_WS;
else
return AVERROR_INVALIDDATA;
/* flag 0 indicates stereo */
wsaud->audio_channels = (header[10] & 0x1) + 1;
/* flag 1 indicates 16 bit audio */
wsaud->audio_bits = (((header[10] & 0x2) >> 1) + 1) * 8;
/* initialize the audio decoder stream */
st = avformat_new_stream(s, NULL);
if (!st)
return AVERROR(ENOMEM);
avpriv_set_pts_info(st, 33, 1, wsaud->audio_samplerate);
st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
st->codec->codec_id = wsaud->audio_type;
st->codec->codec_tag = 0; /* no tag */
st->codec->channels = wsaud->audio_channels;
st->codec->sample_rate = wsaud->audio_samplerate;
st->codec->bits_per_coded_sample = wsaud->audio_bits;
st->codec->bit_rate = st->codec->channels * st->codec->sample_rate *
st->codec->bits_per_coded_sample / 4;
st->codec->block_align = st->codec->channels * st->codec->bits_per_coded_sample;
wsaud->audio_stream_index = st->index;
wsaud->audio_frame_counter = 0;
return 0;
}
static int wsaud_read_packet(AVFormatContext *s,
AVPacket *pkt)
{
WsAudDemuxContext *wsaud = s->priv_data;
AVIOContext *pb = s->pb;
unsigned char preamble[AUD_CHUNK_PREAMBLE_SIZE];
unsigned int chunk_size;
int ret = 0;
if (avio_read(pb, preamble, AUD_CHUNK_PREAMBLE_SIZE) !=
AUD_CHUNK_PREAMBLE_SIZE)
return AVERROR(EIO);
/* validate the chunk */
if (AV_RL32(&preamble[4]) != AUD_CHUNK_SIGNATURE)
return AVERROR_INVALIDDATA;
chunk_size = AV_RL16(&preamble[0]);
ret= av_get_packet(pb, pkt, chunk_size);
if (ret != chunk_size)
return AVERROR(EIO);
pkt->stream_index = wsaud->audio_stream_index;
pkt->pts = wsaud->audio_frame_counter;
pkt->pts /= wsaud->audio_samplerate;
/* 2 samples/byte, 1 or 2 samples per frame depending on stereo */
wsaud->audio_frame_counter += (chunk_size * 2) / wsaud->audio_channels;
return ret;
}
static int wsvqa_probe(AVProbeData *p)
{
/* need 12 bytes to qualify */
@ -372,17 +241,6 @@ static int wsvqa_read_packet(AVFormatContext *s,
return ret;
}
#if CONFIG_WSAUD_DEMUXER
AVInputFormat ff_wsaud_demuxer = {
.name = "wsaud",
.long_name = NULL_IF_CONFIG_SMALL("Westwood Studios audio format"),
.priv_data_size = sizeof(WsAudDemuxContext),
.read_probe = wsaud_probe,
.read_header = wsaud_read_header,
.read_packet = wsaud_read_packet,
};
#endif
#if CONFIG_WSVQA_DEMUXER
AVInputFormat ff_wsvqa_demuxer = {
.name = "wsvqa",
.long_name = NULL_IF_CONFIG_SMALL("Westwood Studios VQA format"),
@ -391,4 +249,3 @@ AVInputFormat ff_wsvqa_demuxer = {
.read_header = wsvqa_read_header,
.read_packet = wsvqa_read_packet,
};
#endif