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avcodec: add a Vorbis parser to get packet duration

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This also allows for removing some of the Vorbis-related hacks.
This commit is contained in:
Justin Ruggles 2012-01-15 13:38:03 -05:00
parent 737ca4482b
commit 5602a464c9
9 changed files with 346 additions and 7 deletions
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1
libavcodec/Makefile
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@ -644,6 +644,7 @@ OBJS-$(CONFIG_RV40_PARSER) += rv34_parser.o
OBJS-$(CONFIG_VC1_PARSER) += vc1_parser.o vc1.o vc1data.o \
msmpeg4.o msmpeg4data.o mpeg4video.o \
h263.o mpegvideo.o error_resilience.o
OBJS-$(CONFIG_VORBIS_PARSER) += vorbis_parser.o xiph.o
OBJS-$(CONFIG_VP3_PARSER) += vp3_parser.o
OBJS-$(CONFIG_VP8_PARSER) += vp8_parser.o

1
libavcodec/allcodecs.c
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@ -416,6 +416,7 @@ void avcodec_register_all(void)
REGISTER_PARSER (RV30, rv30);
REGISTER_PARSER (RV40, rv40);
REGISTER_PARSER (VC1, vc1);
REGISTER_PARSER (VORBIS, vorbis);
REGISTER_PARSER (VP3, vp3);
REGISTER_PARSER (VP8, vp8);

2
libavcodec/version.h
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@ -21,7 +21,7 @@
#define AVCODEC_VERSION_H
#define LIBAVCODEC_VERSION_MAJOR 54
#define LIBAVCODEC_VERSION_MINOR 5
#define LIBAVCODEC_VERSION_MINOR 6
#define LIBAVCODEC_VERSION_MICRO 0
#define LIBAVCODEC_VERSION_INT AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \

270
libavcodec/vorbis_parser.c Normal file
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@ -0,0 +1,270 @@
/*
* Copyright (c) 2012 Justin Ruggles
*
* 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
* Vorbis audio parser
*
* Determines the duration for each packet.
*/
#include "get_bits.h"
#include "parser.h"
#include "xiph.h"
#include "vorbis_parser.h"
static int parse_id_header(AVCodecContext *avctx, VorbisParseContext *s,
const uint8_t *buf, int buf_size)
{
/* Id header should be 30 bytes */
if (buf_size < 30) {
av_log(avctx, AV_LOG_ERROR, "Id header is too short\n");
return AVERROR_INVALIDDATA;
}
/* make sure this is the Id header */
if (buf[0] != 1) {
av_log(avctx, AV_LOG_ERROR, "Wrong packet type in Id header\n");
return AVERROR_INVALIDDATA;
}
/* check for header signature */
if (memcmp(&buf[1], "vorbis", 6)) {
av_log(avctx, AV_LOG_ERROR, "Invalid packet signature in Id header\n");
return AVERROR_INVALIDDATA;
}
if (!(buf[29] & 0x1)) {
av_log(avctx, AV_LOG_ERROR, "Invalid framing bit in Id header\n");
return AVERROR_INVALIDDATA;
}
s->blocksize[0] = 1 << (buf[28] & 0xF);
s->blocksize[1] = 1 << (buf[28] >> 4);
return 0;
}
static int parse_setup_header(AVCodecContext *avctx, VorbisParseContext *s,
const uint8_t *buf, int buf_size)
{
GetBitContext gb, gb0;
uint8_t *rev_buf;
int i, ret = 0;
int got_framing_bit, mode_count, got_mode_header, last_mode_count = 0;
/* avoid overread */
if (buf_size < 7) {
av_log(avctx, AV_LOG_ERROR, "Setup header is too short\n");
return AVERROR_INVALIDDATA;
}
/* make sure this is the Setup header */
if (buf[0] != 5) {
av_log(avctx, AV_LOG_ERROR, "Wrong packet type in Setup header\n");
return AVERROR_INVALIDDATA;
}
/* check for header signature */
if (memcmp(&buf[1], "vorbis", 6)) {
av_log(avctx, AV_LOG_ERROR, "Invalid packet signature in Setup header\n");
return AVERROR_INVALIDDATA;
}
/* reverse bytes so we can easily read backwards with get_bits() */
if (!(rev_buf = av_malloc(buf_size))) {
av_log(avctx, AV_LOG_ERROR, "Out of memory\n");
return AVERROR(ENOMEM);
}
for (i = 0; i < buf_size; i++)
rev_buf[i] = buf[buf_size - 1 - i];
init_get_bits(&gb, rev_buf, buf_size * 8);
got_framing_bit = 0;
while (get_bits_left(&gb) > 97) {
if (get_bits1(&gb)) {
got_framing_bit = get_bits_count(&gb);
break;
}
}
if (!got_framing_bit) {
av_log(avctx, AV_LOG_ERROR, "Invalid Setup header\n");
ret = AVERROR_INVALIDDATA;
goto bad_header;
}
/* Now we search backwards to find possible valid mode counts. This is not
* fool-proof because we could have false positive matches and read too
* far, but there isn't really any way to be sure without parsing through
* all the many variable-sized fields before the modes. This approach seems
* to work well in testing, and it is similar to how it is handled in
* liboggz. */
mode_count = 0;
got_mode_header = 0;
while (get_bits_left(&gb) >= 97) {
if (get_bits(&gb, 8) > 63 || get_bits(&gb, 16) || get_bits(&gb, 16))
break;
skip_bits(&gb, 1);
mode_count++;
if (mode_count > 64)
break;
gb0 = gb;
if (get_bits(&gb0, 6) + 1 == mode_count) {
got_mode_header = 1;
last_mode_count = mode_count;
}
}
if (!got_mode_header) {
av_log(avctx, AV_LOG_ERROR, "Invalid Setup header\n");
ret = AVERROR_INVALIDDATA;
goto bad_header;
}
/* All samples I've seen use <= 2 modes, so ask for a sample if we find
* more than that, as it is most likely a false positive. If we get any
* we may need to approach this the long way and parse the whole Setup
* header, but I hope very much that it never comes to that. */
if (last_mode_count > 2) {
av_log_ask_for_sample(avctx, "%d modes found. This is either a false "
"positive or a sample from an unknown encoder.\n",
last_mode_count);
}
/* We're limiting the mode count to 63 so that we know that the previous
* block flag will be in the first packet byte. */
if (last_mode_count > 63) {
av_log(avctx, AV_LOG_ERROR, "Unsupported mode count: %d\n",
last_mode_count);
ret = AVERROR_INVALIDDATA;
goto bad_header;
}
s->mode_count = mode_count = last_mode_count;
/* Determine the number of bits required to code the mode and turn that
* into a bitmask to directly access the mode from the first frame byte. */
s->mode_mask = ((1 << (av_log2(mode_count - 1) + 1)) - 1) << 1;
/* The previous window flag is the next bit after the mode */
s->prev_mask = (s->mode_mask | 0x1) + 1;
init_get_bits(&gb, rev_buf, buf_size * 8);
skip_bits_long(&gb, got_framing_bit);
for (i = mode_count - 1; i >= 0; i--) {
skip_bits_long(&gb, 40);
s->mode_blocksize[i] = s->blocksize[get_bits1(&gb)];
}
bad_header:
av_free(rev_buf);
return ret;
}
int avpriv_vorbis_parse_extradata(AVCodecContext *avctx, VorbisParseContext *s)
{
uint8_t *header_start[3];
int header_len[3];
int ret;
s->avctx = avctx;
s->extradata_parsed = 1;
if ((ret = avpriv_split_xiph_headers(avctx->extradata,
avctx->extradata_size, 30,
header_start, header_len)) < 0) {
av_log(avctx, AV_LOG_ERROR, "Extradata corrupt.\n");
return ret;
}
if ((ret = parse_id_header(avctx, s, header_start[0], header_len[0])) < 0)
return ret;
if ((ret = parse_setup_header(avctx, s, header_start[2], header_len[2])) < 0)
return ret;
s->valid_extradata = 1;
s->previous_blocksize = s->mode_blocksize[0];
return 0;
}
int avpriv_vorbis_parse_frame(VorbisParseContext *s, const uint8_t *buf,
int buf_size)
{
int duration = 0;
if (s->valid_extradata && buf_size > 0) {
int mode, current_blocksize;
int previous_blocksize = s->previous_blocksize;
if (buf[0] & 1) {
av_log(s->avctx, AV_LOG_ERROR, "Invalid packet\n");
return AVERROR_INVALIDDATA;
}
if (s->mode_count == 1)
mode = 0;
else
mode = (buf[0] & s->mode_mask) >> 1;
if (mode >= s->mode_count) {
av_log(s->avctx, AV_LOG_ERROR, "Invalid mode in packet\n");
return AVERROR_INVALIDDATA;
}
if (mode) {
int flag = !!(buf[0] & s->prev_mask);
previous_blocksize = s->blocksize[flag];
}
current_blocksize = s->mode_blocksize[mode];
duration = (previous_blocksize + current_blocksize) >> 2;
s->previous_blocksize = current_blocksize;
}
return duration;
}
void avpriv_vorbis_parse_reset(VorbisParseContext *s)
{
if (s->valid_extradata)
s->previous_blocksize = s->mode_blocksize[0];
}
#if CONFIG_VORBIS_PARSER
static int vorbis_parse(AVCodecParserContext *s1, AVCodecContext *avctx,
const uint8_t **poutbuf, int *poutbuf_size,
const uint8_t *buf, int buf_size)
{
VorbisParseContext *s = s1->priv_data;
int duration;
if (!s->extradata_parsed && avctx->extradata && avctx->extradata_size)
if (avpriv_vorbis_parse_extradata(avctx, s))
goto end;
if ((duration = avpriv_vorbis_parse_frame(s, buf, buf_size)) >= 0)
s1->duration = duration;
end:
/* always return the full packet. this parser isn't doing any splitting or
combining, only packet analysis */
*poutbuf = buf;
*poutbuf_size = buf_size;
return buf_size;
}
AVCodecParser ff_vorbis_parser = {
.codec_ids = { CODEC_ID_VORBIS },
.priv_data_size = sizeof(VorbisParseContext),
.parser_parse = vorbis_parse,
};
#endif /* CONFIG_VORBIS_PARSER */

68
libavcodec/vorbis_parser.h Normal file
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@ -0,0 +1,68 @@
/*
* Copyright (c) 2012 Justin Ruggles
*
* 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
* Vorbis audio parser
*
* Determines the duration for each packet.
*/
#ifndef AVCODEC_VORBIS_PARSER_H
#define AVCODEC_VORBIS_PARSER_H
#include "avcodec.h"
typedef struct VorbisParseContext {
AVCodecContext *avctx; ///< codec context
int extradata_parsed; ///< we have attempted to parse extradata
int valid_extradata; ///< extradata is valid, so we can calculate duration
int blocksize[2]; ///< short and long window sizes
int previous_blocksize; ///< previous window size
int mode_blocksize[64]; ///< window size mapping for each mode
int mode_count; ///< number of modes
int mode_mask; ///< bitmask used to get the mode in each packet
int prev_mask; ///< bitmask used to get the previous mode flag in each packet
} VorbisParseContext;
/**
* Initialize the Vorbis parser using headers in the extradata.
*
* @param avctx codec context
* @param s Vorbis parser context
*/
int avpriv_vorbis_parse_extradata(AVCodecContext *avctx, VorbisParseContext *s);
/**
* Get the duration for a Vorbis packet.
*
* avpriv_vorbis_parse_extradata() must have been successfully called prior to
* this in order for a correct duration to be returned.
*
* @param s Vorbis parser context
* @param buf buffer containing a Vorbis frame
* @param buf_size size of the buffer
*/
int avpriv_vorbis_parse_frame(VorbisParseContext *s, const uint8_t *buf,
int buf_size);
void avpriv_vorbis_parse_reset(VorbisParseContext *s);
#endif /* AVCODEC_VORBIS_PARSER_H */

1
libavcodec/vorbisdec.c
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@ -1031,7 +1031,6 @@ static av_cold int vorbis_decode_init(AVCodecContext *avccontext)
avccontext->channels = vc->audio_channels;
avccontext->sample_rate = vc->audio_samplerate;
avccontext->frame_size = FFMIN(vc->blocksize[0], vc->blocksize[1]) >> 2;
avcodec_get_frame_defaults(&vc->frame);
avccontext->coded_frame = &vc->frame;

1
libavformat/oggparsevorbis.c
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@ -251,6 +251,7 @@ vorbis_header (AVFormatContext * s, int idx)
st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
st->codec->codec_id = CODEC_ID_VORBIS;
st->need_parsing = AVSTREAM_PARSE_HEADERS;
if (srate > 0) {
st->codec->sample_rate = srate;

3
libavformat/rtpdec.c
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@ -396,6 +396,9 @@ RTPDemuxContext *ff_rtp_parse_open(AVFormatContext *s1, AVStream *st, URLContext
case CODEC_ID_H264:
st->need_parsing = AVSTREAM_PARSE_FULL;
break;
case CODEC_ID_VORBIS:
st->need_parsing = AVSTREAM_PARSE_HEADERS;
break;
case CODEC_ID_ADPCM_G722:
/* According to RFC 3551, the stream clock rate is 8000
* even if the sample rate is 16000. */

6
libavformat/utils.c
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@ -701,9 +701,6 @@ static int get_audio_frame_size(AVCodecContext *enc, int size)
{
int frame_size;
if(enc->codec_id == CODEC_ID_VORBIS)
return -1;
if (enc->frame_size <= 1) {
int bits_per_sample = av_get_bits_per_sample(enc->codec_id);
@ -1995,8 +1992,7 @@ static int has_codec_parameters(AVCodecContext *avctx)
case AVMEDIA_TYPE_AUDIO:
val = avctx->sample_rate && avctx->channels && avctx->sample_fmt != AV_SAMPLE_FMT_NONE;
if (!avctx->frame_size &&
(avctx->codec_id == CODEC_ID_VORBIS ||
avctx->codec_id == CODEC_ID_AAC ||
(avctx->codec_id == CODEC_ID_AAC ||
avctx->codec_id == CODEC_ID_MP1 ||
avctx->codec_id == CODEC_ID_MP2 ||
avctx->codec_id == CODEC_ID_MP3 ||