Commit ff34b2d6 authored by Hendrik Leppkes's avatar Hendrik Leppkes Committed by Michael Niedermayer

mlpdec: support major sync headers with optional extension blocks

Signed-off-by: 's avatarMichael Niedermayer <michaelni@gmx.at>
parent 6821a5a4
......@@ -119,6 +119,23 @@ uint64_t ff_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 @@ uint64_t ff_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;
av_assert1(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)];
......@@ -199,7 +218,7 @@ 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;
}
......
......@@ -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)
......
......@@ -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;
......@@ -349,6 +352,8 @@ 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;
......@@ -1142,7 +1147,7 @@ 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) {
......
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