From 3f1a38c9194d0d1e47469504000997b7bfbcf3b0 Mon Sep 17 00:00:00 2001 From: Alex Converse Date: Thu, 9 Feb 2017 08:22:20 -0800 Subject: [PATCH] aac_latm: Allow unaligned AudioSpecificConfig Fixes ticket 4730 --- libavcodec/aacdec.c | 26 +++++++----- libavcodec/aacdec_template.c | 82 +++++++++++++++++++++++------------- libavcodec/mpeg4audio.c | 76 ++++++++++++++++++--------------- libavcodec/mpeg4audio.h | 12 +++++- 4 files changed, 120 insertions(+), 76 deletions(-) diff --git a/libavcodec/aacdec.c b/libavcodec/aacdec.c index ee9b4eb45f..709ac7cdf8 100644 --- a/libavcodec/aacdec.c +++ b/libavcodec/aacdec.c @@ -284,9 +284,10 @@ static int latm_decode_audio_specific_config(struct LATMContext *latmctx, AACContext *ac = &latmctx->aac_ctx; AVCodecContext *avctx = ac->avctx; MPEG4AudioConfig m4ac = { 0 }; + GetBitContext gbc; int config_start_bit = get_bits_count(gb); int sync_extension = 0; - int bits_consumed, esize; + int bits_consumed, esize, i; if (asclen) { sync_extension = 1; @@ -294,19 +295,19 @@ static int latm_decode_audio_specific_config(struct LATMContext *latmctx, } else asclen = get_bits_left(gb); - if (config_start_bit % 8) { - avpriv_request_sample(latmctx->aac_ctx.avctx, - "Non-byte-aligned audio-specific config"); - return AVERROR_PATCHWELCOME; - } if (asclen <= 0) return AVERROR_INVALIDDATA; - bits_consumed = decode_audio_specific_config(NULL, avctx, &m4ac, - gb->buffer + (config_start_bit / 8), - asclen, sync_extension); - if (bits_consumed < 0) + init_get_bits(&gbc, gb->buffer, config_start_bit + asclen); + skip_bits_long(&gbc, config_start_bit); + + bits_consumed = decode_audio_specific_config_gb(NULL, avctx, &m4ac, + &gbc, config_start_bit, + sync_extension); + + if (bits_consumed < config_start_bit) return AVERROR_INVALIDDATA; + bits_consumed -= config_start_bit; if (!latmctx->initialized || ac->oc[1].m4ac.sample_rate != m4ac.sample_rate || @@ -329,7 +330,10 @@ static int latm_decode_audio_specific_config(struct LATMContext *latmctx, } avctx->extradata_size = esize; - memcpy(avctx->extradata, gb->buffer + (config_start_bit/8), esize); + gbc = *gb; + for (i = 0; i < esize; i++) { + avctx->extradata[i] = get_bits(&gbc, 8); + } memset(avctx->extradata+esize, 0, AV_INPUT_BUFFER_PADDING_SIZE); } skip_bits_long(gb, bits_consumed); diff --git a/libavcodec/aacdec_template.c b/libavcodec/aacdec_template.c index 83e9fb55ba..e230c87733 100644 --- a/libavcodec/aacdec_template.c +++ b/libavcodec/aacdec_template.c @@ -715,6 +715,13 @@ static void decode_channel_map(uint8_t layout_map[][3], } } +static inline void relative_align_get_bits(GetBitContext *gb, + int reference_position) { + int n = (reference_position - get_bits_count(gb) & 7); + if (n) + skip_bits(gb, n); +} + /** * Decode program configuration element; reference: table 4.2. * @@ -722,7 +729,7 @@ static void decode_channel_map(uint8_t layout_map[][3], */ static int decode_pce(AVCodecContext *avctx, MPEG4AudioConfig *m4ac, uint8_t (*layout_map)[3], - GetBitContext *gb) + GetBitContext *gb, int byte_align_ref) { int num_front, num_side, num_back, num_lfe, num_assoc_data, num_cc; int sampling_index; @@ -770,7 +777,7 @@ static int decode_pce(AVCodecContext *avctx, MPEG4AudioConfig *m4ac, decode_channel_map(layout_map + tags, AAC_CHANNEL_CC, gb, num_cc); tags += num_cc; - align_get_bits(gb); + relative_align_get_bits(gb, byte_align_ref); /* comment field, first byte is length */ comment_len = get_bits(gb, 8) * 8; @@ -792,6 +799,7 @@ static int decode_pce(AVCodecContext *avctx, MPEG4AudioConfig *m4ac, */ static int decode_ga_specific_config(AACContext *ac, AVCodecContext *avctx, GetBitContext *gb, + int get_bit_alignment, MPEG4AudioConfig *m4ac, int channel_config) { @@ -815,7 +823,7 @@ static int decode_ga_specific_config(AACContext *ac, AVCodecContext *avctx, if (channel_config == 0) { skip_bits(gb, 4); // element_instance_tag - tags = decode_pce(avctx, m4ac, layout_map, gb); + tags = decode_pce(avctx, m4ac, layout_map, gb, get_bit_alignment); if (tags < 0) return tags; } else { @@ -937,37 +945,25 @@ static int decode_eld_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 buffer holding an audio specific config - * @param bit_size size of audio specific config or data in bits + * @param gb buffer holding an audio specific config + * @param get_bit_alignment relative alignment for byte align operations * @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, int64_t bit_size, - int sync_extension) +static int decode_audio_specific_config_gb(AACContext *ac, + AVCodecContext *avctx, + MPEG4AudioConfig *m4ac, + GetBitContext *gb, + int get_bit_alignment, + int sync_extension) { - GetBitContext gb; int i, ret; + GetBitContext gbc = *gb; - if (bit_size < 0 || bit_size > INT_MAX) { - av_log(avctx, AV_LOG_ERROR, "Audio specific config size is invalid\n"); + if ((i = ff_mpeg4audio_get_config_gb(m4ac, &gbc, sync_extension)) < 0) return AVERROR_INVALIDDATA; - } - ff_dlog(avctx, "audio specific config size %d\n", (int)bit_size >> 3); - for (i = 0; i < bit_size >> 3; i++) - ff_dlog(avctx, "%02x ", data[i]); - ff_dlog(avctx, "\n"); - - if ((ret = init_get_bits(&gb, data, bit_size)) < 0) - return ret; - - if ((i = avpriv_mpeg4audio_get_config(m4ac, data, bit_size, - sync_extension)) < 0) - return AVERROR_INVALIDDATA; if (m4ac->sampling_index > 12) { av_log(avctx, AV_LOG_ERROR, "invalid sampling rate index %d\n", @@ -982,7 +978,7 @@ static int decode_audio_specific_config(AACContext *ac, return AVERROR_INVALIDDATA; } - skip_bits_long(&gb, i); + skip_bits_long(gb, i); switch (m4ac->object_type) { case AOT_AAC_MAIN: @@ -990,12 +986,12 @@ static int decode_audio_specific_config(AACContext *ac, case AOT_AAC_LTP: case AOT_ER_AAC_LC: case AOT_ER_AAC_LD: - if ((ret = decode_ga_specific_config(ac, avctx, &gb, + if ((ret = decode_ga_specific_config(ac, avctx, gb, get_bit_alignment, m4ac, m4ac->chan_config)) < 0) return ret; break; case AOT_ER_AAC_ELD: - if ((ret = decode_eld_specific_config(ac, avctx, &gb, + if ((ret = decode_eld_specific_config(ac, avctx, gb, m4ac, m4ac->chan_config)) < 0) return ret; break; @@ -1013,7 +1009,33 @@ static int decode_audio_specific_config(AACContext *ac, m4ac->sample_rate, m4ac->sbr, m4ac->ps); - return get_bits_count(&gb); + return get_bits_count(gb); +} + +static int decode_audio_specific_config(AACContext *ac, + AVCodecContext *avctx, + MPEG4AudioConfig *m4ac, + const uint8_t *data, int64_t bit_size, + int sync_extension) +{ + int i, ret; + GetBitContext gb; + + if (bit_size < 0 || bit_size > INT_MAX) { + av_log(avctx, AV_LOG_ERROR, "Audio specific config size is invalid\n"); + return AVERROR_INVALIDDATA; + } + + ff_dlog(avctx, "audio specific config size %d\n", (int)bit_size >> 3); + for (i = 0; i < bit_size >> 3; i++) + ff_dlog(avctx, "%02x ", data[i]); + ff_dlog(avctx, "\n"); + + if ((ret = init_get_bits(&gb, data, bit_size)) < 0) + return ret; + + return decode_audio_specific_config_gb(ac, avctx, m4ac, &gb, 0, + sync_extension); } /** @@ -3003,7 +3025,7 @@ static int aac_decode_frame_int(AVCodecContext *avctx, void *data, uint8_t layout_map[MAX_ELEM_ID*4][3]; int tags; push_output_configuration(ac); - tags = decode_pce(avctx, &ac->oc[1].m4ac, layout_map, gb); + tags = decode_pce(avctx, &ac->oc[1].m4ac, layout_map, gb, 0); if (tags < 0) { err = tags; break; diff --git a/libavcodec/mpeg4audio.c b/libavcodec/mpeg4audio.c index 5f85b64cb8..b6bb323440 100644 --- a/libavcodec/mpeg4audio.c +++ b/libavcodec/mpeg4audio.c @@ -83,70 +83,62 @@ 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 bit_size, int sync_extension) +int ff_mpeg4audio_get_config_gb(MPEG4AudioConfig *c, GetBitContext *gb, + int sync_extension) { - GetBitContext gb; int specific_config_bitindex, ret; - - if (bit_size <= 0) - return AVERROR_INVALIDDATA; - - ret = init_get_bits(&gb, buf, bit_size); - if (ret < 0) - return ret; - - c->object_type = get_object_type(&gb); - c->sample_rate = get_sample_rate(&gb, &c->sampling_index); - c->chan_config = get_bits(&gb, 4); + int start_bit_index = get_bits_count(gb); + c->object_type = get_object_type(gb); + c->sample_rate = get_sample_rate(gb, &c->sampling_index); + c->chan_config = get_bits(gb, 4); if (c->chan_config < FF_ARRAY_ELEMS(ff_mpeg4audio_channels)) c->channels = ff_mpeg4audio_channels[c->chan_config]; c->sbr = -1; c->ps = -1; if (c->object_type == AOT_SBR || (c->object_type == AOT_PS && // check for W6132 Annex YYYY draft MP3onMP4 - !(show_bits(&gb, 3) & 0x03 && !(show_bits(&gb, 9) & 0x3F)))) { + !(show_bits(gb, 3) & 0x03 && !(show_bits(gb, 9) & 0x3F)))) { if (c->object_type == AOT_PS) c->ps = 1; c->ext_object_type = AOT_SBR; c->sbr = 1; - c->ext_sample_rate = get_sample_rate(&gb, &c->ext_sampling_index); - c->object_type = get_object_type(&gb); + c->ext_sample_rate = get_sample_rate(gb, &c->ext_sampling_index); + c->object_type = get_object_type(gb); if (c->object_type == AOT_ER_BSAC) - c->ext_chan_config = get_bits(&gb, 4); + c->ext_chan_config = get_bits(gb, 4); } else { c->ext_object_type = AOT_NULL; c->ext_sample_rate = 0; } - specific_config_bitindex = get_bits_count(&gb); + specific_config_bitindex = get_bits_count(gb); if (c->object_type == AOT_ALS) { - skip_bits(&gb, 5); - if (show_bits_long(&gb, 24) != MKBETAG('\0','A','L','S')) - skip_bits_long(&gb, 24); + skip_bits(gb, 5); + if (show_bits_long(gb, 24) != MKBETAG('\0','A','L','S')) + skip_bits_long(gb, 24); - specific_config_bitindex = get_bits_count(&gb); + specific_config_bitindex = get_bits_count(gb); - ret = parse_config_ALS(&gb, c); + ret = parse_config_ALS(gb, c); if (ret < 0) return ret; } 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); - c->ext_object_type = get_object_type(&gb); - if (c->ext_object_type == AOT_SBR && (c->sbr = get_bits1(&gb)) == 1) { - c->ext_sample_rate = get_sample_rate(&gb, &c->ext_sampling_index); + while (get_bits_left(gb) > 15) { + if (show_bits(gb, 11) == 0x2b7) { // sync extension + get_bits(gb, 11); + c->ext_object_type = get_object_type(gb); + if (c->ext_object_type == AOT_SBR && (c->sbr = get_bits1(gb)) == 1) { + c->ext_sample_rate = get_sample_rate(gb, &c->ext_sampling_index); if (c->ext_sample_rate == c->sample_rate) c->sbr = -1; } - if (get_bits_left(&gb) > 11 && get_bits(&gb, 11) == 0x548) - c->ps = get_bits1(&gb); + if (get_bits_left(gb) > 11 && get_bits(gb, 11) == 0x548) + c->ps = get_bits1(gb); break; } else - get_bits1(&gb); // skip 1 bit + get_bits1(gb); // skip 1 bit } } @@ -157,7 +149,23 @@ int avpriv_mpeg4audio_get_config(MPEG4AudioConfig *c, const uint8_t *buf, if ((c->ps == -1 && c->object_type != AOT_AAC_LC) || c->channels & ~0x01) c->ps = 0; - return specific_config_bitindex; + return specific_config_bitindex - start_bit_index; +} + +int avpriv_mpeg4audio_get_config(MPEG4AudioConfig *c, const uint8_t *buf, + int bit_size, int sync_extension) +{ + GetBitContext gb; + int ret; + + if (bit_size <= 0) + return AVERROR_INVALIDDATA; + + ret = init_get_bits(&gb, buf, bit_size); + if (ret < 0) + return ret; + + return ff_mpeg4audio_get_config_gb(c, &gb, sync_extension); } static av_always_inline unsigned int copy_bits(PutBitContext *pb, diff --git a/libavcodec/mpeg4audio.h b/libavcodec/mpeg4audio.h index 8239081747..8fd32f96b3 100644 --- a/libavcodec/mpeg4audio.h +++ b/libavcodec/mpeg4audio.h @@ -45,7 +45,17 @@ extern av_export const int avpriv_mpeg4audio_sample_rates[16]; extern const uint8_t ff_mpeg4audio_channels[8]; /** - * Parse MPEG-4 systems extradata to retrieve audio configuration. + * Parse MPEG-4 systems extradata from a potentially unaligned GetBitContext to retrieve audio configuration. + * @param[in] c MPEG4AudioConfig structure to fill. + * @param[in] gb Extradata from container. + * @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 ff_mpeg4audio_get_config_gb(MPEG4AudioConfig *c, GetBitContext *gb, + int sync_extension); + +/** + * Parse MPEG-4 systems extradata from a raw buffer to retrieve audio configuration. * @param[in] c MPEG4AudioConfig structure to fill. * @param[in] buf Extradata from container. * @param[in] bit_size Extradata size in bits.