From fd095539d10bb440042e671f95306b16b0fec674 Mon Sep 17 00:00:00 2001 From: Janne Grunau Date: Fri, 21 Oct 2011 17:25:30 +0200 Subject: 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. --- libavcodec/aacdec.c | 35 ++++++++++++++++++++++------------- 1 file changed, 22 insertions(+), 13 deletions(-) (limited to 'libavcodec/aacdec.c') diff --git a/libavcodec/aacdec.c b/libavcodec/aacdec.c index 672ba1c648..a4fe2ee2cc 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; } -- cgit v1.2.3