[FFmpeg-cvslog] latmdec: fix audio specific config parsing
Janne Grunau
git at videolan.org
Sat Dec 3 03:13:10 CET 2011
ffmpeg | branch: master | Janne Grunau <janne-libav at jannau.net> | Fri Oct 21 17:25:30 2011 +0200| [fd095539d10bb440042e671f95306b16b0fec674] | committer: Janne Grunau
latmdec: fix audio specific config parsing
Pass the correct size in bits to mpeg4audio_get_config and add a flag
to disable parsing of the sync extension when the size is not known.
Latm with AudioMuxVersion 0 does not specify the size of the audio
specific config. Data after the audio specific config can be
misinterpreted as sync extension resulting in random and wrong configs.
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=fd095539d10bb440042e671f95306b16b0fec674
---
libavcodec/aacdec.c | 35 ++++++++++++++++++++++-------------
libavcodec/alsdec.c | 2 +-
libavcodec/mpeg4audio.c | 7 ++++---
libavcodec/mpeg4audio.h | 7 +++++--
libavcodec/mpegaudiodec.c | 3 ++-
libavformat/adtsenc.c | 2 +-
libavformat/flvdec.c | 2 +-
libavformat/isom.c | 2 +-
libavformat/latmenc.c | 2 +-
libavformat/matroskaenc.c | 3 ++-
10 files changed, 40 insertions(+), 25 deletions(-)
diff --git a/libavcodec/aacdec.c b/libavcodec/aacdec.c
index 672ba1c..a4fe2ee 100644
--- a/libavcodec/aacdec.c
+++ b/libavcodec/aacdec.c
@@ -452,15 +452,17 @@ static int decode_ga_specific_config(AACContext *ac, AVCodecContext *avctx,
* @param ac pointer to AACContext, may be null
* @param avctx pointer to AVCCodecContext, used for logging
* @param m4ac pointer to MPEG4AudioConfig, used for parsing
- * @param data pointer to AVCodecContext extradata
- * @param data_size size of AVCCodecContext extradata
+ * @param data pointer to buffer holding an audio specific config
+ * @param bit_size size of audio specific config or data in bits
+ * @param sync_extension look for an appended sync extension
*
* @return Returns error status or number of consumed bits. <0 - error
*/
static int decode_audio_specific_config(AACContext *ac,
AVCodecContext *avctx,
MPEG4AudioConfig *m4ac,
- const uint8_t *data, int data_size)
+ const uint8_t *data, int bit_size,
+ int sync_extension)
{
GetBitContext gb;
int i;
@@ -470,9 +472,9 @@ static int decode_audio_specific_config(AACContext *ac,
av_dlog(avctx, "%02x ", avctx->extradata[i]);
av_dlog(avctx, "\n");
- init_get_bits(&gb, data, data_size * 8);
+ init_get_bits(&gb, data, bit_size);
- if ((i = avpriv_mpeg4audio_get_config(m4ac, data, data_size)) < 0)
+ if ((i = avpriv_mpeg4audio_get_config(m4ac, data, bit_size, sync_extension)) < 0)
return -1;
if (m4ac->sampling_index > 12) {
av_log(avctx, AV_LOG_ERROR, "invalid sampling rate index %d\n", m4ac->sampling_index);
@@ -572,7 +574,7 @@ static av_cold int aac_decode_init(AVCodecContext *avctx)
if (avctx->extradata_size > 0) {
if (decode_audio_specific_config(ac, ac->avctx, &ac->m4ac,
avctx->extradata,
- avctx->extradata_size) < 0)
+ avctx->extradata_size*8, 1) < 0)
return -1;
} else {
int sr, i;
@@ -2315,12 +2317,19 @@ static inline uint32_t latm_get_value(GetBitContext *b)
}
static int latm_decode_audio_specific_config(struct LATMContext *latmctx,
- GetBitContext *gb)
+ GetBitContext *gb, int asclen)
{
AVCodecContext *avctx = latmctx->aac_ctx.avctx;
MPEG4AudioConfig m4ac;
- int config_start_bit = get_bits_count(gb);
- int bits_consumed, esize;
+ int config_start_bit = get_bits_count(gb);
+ int sync_extension = 0;
+ int bits_consumed, esize;
+
+ if (asclen) {
+ sync_extension = 1;
+ asclen = FFMIN(asclen, get_bits_left(gb));
+ } else
+ asclen = get_bits_left(gb);
if (config_start_bit % 8) {
av_log_missing_feature(latmctx->aac_ctx.avctx, "audio specific "
@@ -2330,7 +2339,7 @@ static int latm_decode_audio_specific_config(struct LATMContext *latmctx,
bits_consumed =
decode_audio_specific_config(NULL, avctx, &m4ac,
gb->buffer + (config_start_bit / 8),
- get_bits_left(gb) / 8);
+ asclen, sync_extension);
if (bits_consumed < 0)
return AVERROR_INVALIDDATA;
@@ -2388,11 +2397,11 @@ static int read_stream_mux_config(struct LATMContext *latmctx,
// for all but first stream: use_same_config = get_bits(gb, 1);
if (!audio_mux_version) {
- if ((ret = latm_decode_audio_specific_config(latmctx, gb)) < 0)
+ if ((ret = latm_decode_audio_specific_config(latmctx, gb, 0)) < 0)
return ret;
} else {
int ascLen = latm_get_value(gb);
- if ((ret = latm_decode_audio_specific_config(latmctx, gb)) < 0)
+ if ((ret = latm_decode_audio_specific_config(latmctx, gb, ascLen)) < 0)
return ret;
ascLen -= ret;
skip_bits_long(gb, ascLen);
@@ -2514,7 +2523,7 @@ static int latm_decode_frame(AVCodecContext *avctx, void *out,
} else {
if ((err = decode_audio_specific_config(
&latmctx->aac_ctx, avctx, &latmctx->aac_ctx.m4ac,
- avctx->extradata, avctx->extradata_size)) < 0)
+ avctx->extradata, avctx->extradata_size*8, 1)) < 0)
return err;
latmctx->initialized = 1;
}
diff --git a/libavcodec/alsdec.c b/libavcodec/alsdec.c
index 7149580..dc4961c 100644
--- a/libavcodec/alsdec.c
+++ b/libavcodec/alsdec.c
@@ -291,7 +291,7 @@ static av_cold int read_specific_config(ALSDecContext *ctx)
init_get_bits(&gb, avctx->extradata, avctx->extradata_size * 8);
config_offset = avpriv_mpeg4audio_get_config(&m4ac, avctx->extradata,
- avctx->extradata_size);
+ avctx->extradata_size * 8, 1);
if (config_offset < 0)
return -1;
diff --git a/libavcodec/mpeg4audio.c b/libavcodec/mpeg4audio.c
index f9e866f..0fb9b96 100644
--- a/libavcodec/mpeg4audio.c
+++ b/libavcodec/mpeg4audio.c
@@ -76,12 +76,13 @@ static inline int get_sample_rate(GetBitContext *gb, int *index)
avpriv_mpeg4audio_sample_rates[*index];
}
-int avpriv_mpeg4audio_get_config(MPEG4AudioConfig *c, const uint8_t *buf, int buf_size)
+int avpriv_mpeg4audio_get_config(MPEG4AudioConfig *c, const uint8_t *buf,
+ int bit_size, int sync_extension)
{
GetBitContext gb;
int specific_config_bitindex;
- init_get_bits(&gb, buf, buf_size*8);
+ init_get_bits(&gb, buf, bit_size);
c->object_type = get_object_type(&gb);
c->sample_rate = get_sample_rate(&gb, &c->sampling_index);
c->chan_config = get_bits(&gb, 4);
@@ -117,7 +118,7 @@ int avpriv_mpeg4audio_get_config(MPEG4AudioConfig *c, const uint8_t *buf, int bu
return -1;
}
- if (c->ext_object_type != AOT_SBR) {
+ if (c->ext_object_type != AOT_SBR && sync_extension) {
while (get_bits_left(&gb) > 15) {
if (show_bits(&gb, 11) == 0x2b7) { // sync extension
get_bits(&gb, 11);
diff --git a/libavcodec/mpeg4audio.h b/libavcodec/mpeg4audio.h
index d6730b9..7560f3f 100644
--- a/libavcodec/mpeg4audio.h
+++ b/libavcodec/mpeg4audio.h
@@ -42,14 +42,17 @@ typedef struct {
extern const int avpriv_mpeg4audio_sample_rates[16];
extern const uint8_t ff_mpeg4audio_channels[8];
+
/**
* Parse MPEG-4 systems extradata to retrieve audio configuration.
* @param[in] c MPEG4AudioConfig structure to fill.
* @param[in] buf Extradata from container.
- * @param[in] buf_size Extradata size.
+ * @param[in] bit_size Extradata size in bits.
+ * @param[in] sync_extension look for a sync extension after config if true.
* @return On error -1 is returned, on success AudioSpecificConfig bit index in extradata.
*/
-int avpriv_mpeg4audio_get_config(MPEG4AudioConfig *c, const uint8_t *buf, int buf_size);
+int avpriv_mpeg4audio_get_config(MPEG4AudioConfig *c, const uint8_t *buf,
+ int bit_size, int sync_extension);
enum AudioObjectType {
AOT_NULL,
diff --git a/libavcodec/mpegaudiodec.c b/libavcodec/mpegaudiodec.c
index c819bc5..eeef470 100644
--- a/libavcodec/mpegaudiodec.c
+++ b/libavcodec/mpegaudiodec.c
@@ -1966,7 +1966,8 @@ static int decode_init_mp3on4(AVCodecContext * avctx)
return AVERROR_INVALIDDATA;
}
- avpriv_mpeg4audio_get_config(&cfg, avctx->extradata, avctx->extradata_size);
+ avpriv_mpeg4audio_get_config(&cfg, avctx->extradata,
+ avctx->extradata_size * 8, 1);
if (!cfg.chan_config || cfg.chan_config > 7) {
av_log(avctx, AV_LOG_ERROR, "Invalid channel config number.\n");
return AVERROR_INVALIDDATA;
diff --git a/libavformat/adtsenc.c b/libavformat/adtsenc.c
index 55fece5..ef3d8e2 100644
--- a/libavformat/adtsenc.c
+++ b/libavformat/adtsenc.c
@@ -37,7 +37,7 @@ int ff_adts_decode_extradata(AVFormatContext *s, ADTSContext *adts, uint8_t *buf
int off;
init_get_bits(&gb, buf, size * 8);
- off = avpriv_mpeg4audio_get_config(&m4ac, buf, size);
+ off = avpriv_mpeg4audio_get_config(&m4ac, buf, size * 8, 1);
if (off < 0)
return off;
skip_bits_long(&gb, off);
diff --git a/libavformat/flvdec.c b/libavformat/flvdec.c
index 5d19dd8..51a8126 100644
--- a/libavformat/flvdec.c
+++ b/libavformat/flvdec.c
@@ -534,7 +534,7 @@ static int flv_read_packet(AVFormatContext *s, AVPacket *pkt)
if (st->codec->codec_id == CODEC_ID_AAC) {
MPEG4AudioConfig cfg;
avpriv_mpeg4audio_get_config(&cfg, st->codec->extradata,
- st->codec->extradata_size);
+ st->codec->extradata_size * 8, 1);
st->codec->channels = cfg.channels;
if (cfg.ext_sample_rate)
st->codec->sample_rate = cfg.ext_sample_rate;
diff --git a/libavformat/isom.c b/libavformat/isom.c
index b0eef37..7b9f91b 100644
--- a/libavformat/isom.c
+++ b/libavformat/isom.c
@@ -436,7 +436,7 @@ int ff_mp4_read_dec_config_descr(AVFormatContext *fc, AVStream *st, AVIOContext
if (st->codec->codec_id == CODEC_ID_AAC) {
MPEG4AudioConfig cfg;
avpriv_mpeg4audio_get_config(&cfg, st->codec->extradata,
- st->codec->extradata_size);
+ st->codec->extradata_size * 8, 1);
st->codec->channels = cfg.channels;
if (cfg.object_type == 29 && cfg.sampling_index < 3) // old mp3on4
st->codec->sample_rate = avpriv_mpa_freq_tab[cfg.sampling_index];
diff --git a/libavformat/latmenc.c b/libavformat/latmenc.c
index 679f2cc..423710d 100644
--- a/libavformat/latmenc.c
+++ b/libavformat/latmenc.c
@@ -54,7 +54,7 @@ static int latm_decode_extradata(LATMContext *ctx, uint8_t *buf, int size)
MPEG4AudioConfig m4ac;
init_get_bits(&gb, buf, size * 8);
- ctx->off = avpriv_mpeg4audio_get_config(&m4ac, buf, size);
+ ctx->off = avpriv_mpeg4audio_get_config(&m4ac, buf, size * 8, 1);
if (ctx->off < 0)
return ctx->off;
skip_bits_long(&gb, ctx->off);
diff --git a/libavformat/matroskaenc.c b/libavformat/matroskaenc.c
index b8c73bf..9f8d5d8 100644
--- a/libavformat/matroskaenc.c
+++ b/libavformat/matroskaenc.c
@@ -448,7 +448,8 @@ static void get_aac_sample_rates(AVFormatContext *s, AVCodecContext *codec, int
{
MPEG4AudioConfig mp4ac;
- if (avpriv_mpeg4audio_get_config(&mp4ac, codec->extradata, codec->extradata_size) < 0) {
+ if (avpriv_mpeg4audio_get_config(&mp4ac, codec->extradata,
+ codec->extradata_size * 8, 1) < 0) {
av_log(s, AV_LOG_WARNING, "Error parsing AAC extradata, unable to determine samplerate.\n");
return;
}
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