From d46e6f2723d51a9aa0c09e69bbc17ae71774b7c1 Mon Sep 17 00:00:00 2001 From: Hendrik Leppkes Date: Fri, 26 Sep 2014 13:49:20 +0200 Subject: [PATCH 1/2] mlpdec: support major sync headers with optional extension blocks Signed-off-by: Anton Khirnov (cherry picked from commit f36f6a608b5b2c17f8876195c61621c8f8607cee) Signed-off-by: Tim Walker --- libavcodec/mlp_parser.c | 29 ++++++++++++++++++++++++----- libavcodec/mlp_parser.h | 1 + libavcodec/mlpdec.c | 7 ++++++- 3 files changed, 31 insertions(+), 6 deletions(-) diff --git a/libavcodec/mlp_parser.c b/libavcodec/mlp_parser.c index 075227f..0c7d4a2 100644 --- a/libavcodec/mlp_parser.c +++ b/libavcodec/mlp_parser.c @@ -119,6 +119,23 @@ static uint64_t truehd_layout(int chanmap) return layout; } +static int ff_mlp_get_major_sync_size(const uint8_t * buf, int bufsize) +{ + int has_extension, extensions = 0; + int size = 28; + if (bufsize < 28) + return -1; + + if (AV_RB32(buf) == 0xf8726fba) { + has_extension = buf[25] & 1; + if (has_extension) { + extensions = buf[26] >> 4; + size += 2 + extensions * 2; + } + } + return size; +} + /** Read a major sync info header - contains high level information about * the stream - sample rate, channel arrangement etc. Most of this * information is not actually necessary for decoding, only for playback. @@ -127,18 +144,19 @@ static uint64_t truehd_layout(int chanmap) int ff_mlp_read_major_sync(void *log, MLPHeaderInfo *mh, GetBitContext *gb) { - int ratebits, channel_arrangement; + int ratebits, channel_arrangement, header_size; uint16_t checksum; assert(get_bits_count(gb) == 0); - if (gb->size_in_bits < 28 << 3) { + header_size = ff_mlp_get_major_sync_size(gb->buffer, gb->size_in_bits >> 3); + if (header_size < 0 || gb->size_in_bits < header_size << 3) { av_log(log, AV_LOG_ERROR, "packet too short, unable to read major sync\n"); return -1; } - checksum = ff_mlp_checksum16(gb->buffer, 26); - if (checksum != AV_RL16(gb->buffer+26)) { + checksum = ff_mlp_checksum16(gb->buffer, header_size - 2); + if (checksum != AV_RL16(gb->buffer+header_size-2)) { av_log(log, AV_LOG_ERROR, "major sync info header checksum error\n"); return AVERROR_INVALIDDATA; } @@ -147,6 +165,7 @@ int ff_mlp_read_major_sync(void *log, MLPHeaderInfo *mh, GetBitContext *gb) return AVERROR_INVALIDDATA; mh->stream_type = get_bits(gb, 8); + mh->header_size = header_size; if (mh->stream_type == 0xbb) { mh->group1_bits = mlp_quants[get_bits(gb, 4)]; @@ -197,7 +216,7 @@ int ff_mlp_read_major_sync(void *log, MLPHeaderInfo *mh, GetBitContext *gb) mh->num_substreams = get_bits(gb, 4); - skip_bits_long(gb, 4 + 11 * 8); + skip_bits_long(gb, 4 + (header_size - 17) * 8); return 0; } diff --git a/libavcodec/mlp_parser.h b/libavcodec/mlp_parser.h index 7530fac..06ab421 100644 --- a/libavcodec/mlp_parser.h +++ b/libavcodec/mlp_parser.h @@ -32,6 +32,7 @@ typedef struct MLPHeaderInfo { int stream_type; ///< 0xBB for MLP, 0xBA for TrueHD + int header_size; ///< Size of the major sync header, in bytes int group1_bits; ///< The bit depth of the first substream int group2_bits; ///< Bit depth of the second substream (MLP only) diff --git a/libavcodec/mlpdec.c b/libavcodec/mlpdec.c index 6baf4c1..ad9e54f 100644 --- a/libavcodec/mlpdec.c +++ b/libavcodec/mlpdec.c @@ -132,6 +132,9 @@ typedef struct MLPDecodeContext { /// Current access unit being read has a major sync. int is_major_sync_unit; + /// Size of the major sync unit, in bytes + int major_sync_header_size; + /// Set if a valid major sync block has been read. Otherwise no decoding is possible. uint8_t params_valid; @@ -346,6 +349,8 @@ static int read_major_sync(MLPDecodeContext *m, GetBitContext *gb) return AVERROR_PATCHWELCOME; } + m->major_sync_header_size = mh.header_size; + m->access_unit_size = mh.access_unit_size; m->access_unit_size_pow2 = mh.access_unit_size_pow2; @@ -1105,7 +1110,7 @@ static int read_access_unit(AVCodecContext *avctx, void* data, if (read_major_sync(m, &gb) < 0) goto error; m->is_major_sync_unit = 1; - header_size += 28; + header_size += m->major_sync_header_size; } if (!m->params_valid) { -- 2.4.9 (Apple Git-60) From 99d4726e198d321158139f327c9c21dec58bc376 Mon Sep 17 00:00:00 2001 From: Hendrik Leppkes Date: Fri, 26 Sep 2014 13:49:21 +0200 Subject: [PATCH 2/2] mlpdec: support TrueHD streams with an Atmos substream The fourth substream is being discarded, since its not raw audio data, but an encoded Atmos stream which needs a specialized decoder. Fixes decoding of the true hd stream from Transformers\ -\ Age\ of\ Extinction\ 2014\ 1080P-003.mkv Signed-off-by: Anton Khirnov (cherry picked from commit dc2d0e06af459af9a7f91b65e0a3119acc4f1baa) Signed-off-by: Tim Walker --- libavcodec/mlp.h | 2 +- libavcodec/mlpdec.c | 4 +++- 2 files changed, 4 insertions(+), 2 deletions(-) diff --git a/libavcodec/mlp.h b/libavcodec/mlp.h index 5a4ee5f..8a1584e 100644 --- a/libavcodec/mlp.h +++ b/libavcodec/mlp.h @@ -45,7 +45,7 @@ /** Maximum number of substreams that can be decoded. * MLP's limit is 2. TrueHD supports at least up to 3. */ -#define MAX_SUBSTREAMS 3 +#define MAX_SUBSTREAMS 4 /** which multiple of 48000 the maximum sample rate is */ #define MAX_RATEFACTOR 4 diff --git a/libavcodec/mlpdec.c b/libavcodec/mlpdec.c index ad9e54f..5ace18d 100644 --- a/libavcodec/mlpdec.c +++ b/libavcodec/mlpdec.c @@ -355,7 +355,9 @@ static int read_major_sync(MLPDecodeContext *m, GetBitContext *gb) m->access_unit_size_pow2 = mh.access_unit_size_pow2; m->num_substreams = mh.num_substreams; - m->max_decoded_substream = m->num_substreams - 1; + + /* limit to decoding 3 substreams, as the 4th is used by Dolby Atmos for non-audio data */ + m->max_decoded_substream = FFMIN(m->num_substreams - 1, 2); m->avctx->sample_rate = mh.group1_samplerate; m->avctx->frame_size = mh.access_unit_size; -- 2.4.9 (Apple Git-60)