mlp: store the channel layout for each substream.

Also stop storing the channel arrangement in the header info, as it's unused outside of ff_mlp_read_major_sync.
Signed-off-by: Justin Ruggles <justin.ruggles@gmail.com>

CC:libav-stable@libav.org

libavcodec/mlp_parser.c

@@ -126,7 +126,7 @@ static uint64_t truehd_layout(int chanmap)
 
 int ff_mlp_read_major_sync(void *log, MLPHeaderInfo *mh, GetBitContext *gb)
 {
-    int ratebits;
+    int ratebits, channel_arrangement;
     uint16_t checksum;
 
     assert(get_bits_count(gb) == 0);
@@ -157,7 +157,9 @@ int ff_mlp_read_major_sync(void *log, MLPHeaderInfo *mh, GetBitContext *gb)
 
         skip_bits(gb, 11);
 
-        mh->channels_mlp = get_bits(gb, 5);
+        channel_arrangement    = get_bits(gb, 5);
+        mh->channels_mlp       = mlp_channels[channel_arrangement];
+        mh->channel_layout_mlp = mlp_layout[channel_arrangement];
     } else if (mh->stream_type == 0xba) {
         mh->group1_bits = 24; // TODO: Is this information actually conveyed anywhere?
         mh->group2_bits = 0;
@@ -168,11 +170,15 @@ int ff_mlp_read_major_sync(void *log, MLPHeaderInfo *mh, GetBitContext *gb)
 
         skip_bits(gb, 8);
 
-        mh->channels_thd_stream1 = get_bits(gb, 5);
+        channel_arrangement            = get_bits(gb, 5);
+        mh->channels_thd_stream1       = truehd_channels(channel_arrangement);
+        mh->channel_layout_thd_stream1 = truehd_layout(channel_arrangement);
 
         skip_bits(gb, 2);
 
-        mh->channels_thd_stream2 = get_bits(gb, 13);
+        channel_arrangement            = get_bits(gb, 13);
+        mh->channels_thd_stream2       = truehd_channels(channel_arrangement);
+        mh->channel_layout_thd_stream2 = truehd_layout(channel_arrangement);
     } else
         return AVERROR_INVALIDDATA;
 
@@ -316,16 +322,16 @@ static int mlp_parse(AVCodecParserContext *s,
 
         if (mh.stream_type == 0xbb) {
             /* MLP stream */
-            avctx->channels = mlp_channels[mh.channels_mlp];
-            avctx->channel_layout = mlp_layout[mh.channels_mlp];
+            avctx->channels       = mh.channels_mlp;
+            avctx->channel_layout = mh.channel_layout_mlp;
         } else { /* mh.stream_type == 0xba */
             /* TrueHD stream */
             if (mh.channels_thd_stream2) {
-                avctx->channels = truehd_channels(mh.channels_thd_stream2);
-                avctx->channel_layout = truehd_layout(mh.channels_thd_stream2);
+                avctx->channels       = mh.channels_thd_stream2;
+                avctx->channel_layout = mh.channel_layout_thd_stream2;
             } else {
-                avctx->channels = truehd_channels(mh.channels_thd_stream1);
-                avctx->channel_layout = truehd_layout(mh.channels_thd_stream1);
+                avctx->channels       = mh.channels_thd_stream1;
+                avctx->channel_layout = mh.channel_layout_thd_stream1;
             }
         }
 

libavcodec/mlp_parser.h

@@ -39,9 +39,12 @@ typedef struct MLPHeaderInfo
     int group1_samplerate;      ///< Sample rate of first substream
     int group2_samplerate;      ///< Sample rate of second substream (MLP only)
 
-    int channels_mlp;           ///< Channel arrangement for MLP streams
-    int channels_thd_stream1;   ///< Channel arrangement for substream 1 of TrueHD streams (5.1)
-    int channels_thd_stream2;   ///< Channel arrangement for substream 2 of TrueHD streams (7.1)
+    int channels_mlp;                       ///< Channel count for MLP streams
+    int channels_thd_stream1;               ///< Channel count for substream 1 of TrueHD streams ("6-channel presentation")
+    int channels_thd_stream2;               ///< Channel count for substream 2 of TrueHD streams ("8-channel presentation")
+    uint64_t channel_layout_mlp;            ///< Channel layout for MLP streams
+    uint64_t channel_layout_thd_stream1;    ///< Channel layout for substream 1 of TrueHD streams ("6-channel presentation")
+    uint64_t channel_layout_thd_stream2;    ///< Channel layout for substream 2 of TrueHD streams ("8-channel presentation")
 
     int access_unit_size;       ///< Number of samples per coded frame
     int access_unit_size_pow2;  ///< Next power of two above number of samples per frame

libavcodec/mlpdec.c

@@ -28,6 +28,7 @@
 
 #include "avcodec.h"
 #include "libavutil/intreadwrite.h"
+#include "libavutil/channel_layout.h"
 #include "get_bits.h"
 #include "internal.h"
 #include "libavutil/crc.h"
@@ -56,6 +57,8 @@ typedef struct SubStream {
     uint8_t     max_matrix_channel;
     /// For each channel output by the matrix, the output channel to map it to
     uint8_t     ch_assign[MAX_CHANNELS];
+    /// The channel layout for this substream
+    uint64_t    ch_layout;
 
     /// Channel coding parameters for channels in the substream
     ChannelParams channel_params[MAX_CHANNELS];
@@ -325,6 +328,24 @@ static int read_major_sync(MLPDecodeContext *m, GetBitContext *gb)
     for (substr = 0; substr < MAX_SUBSTREAMS; substr++)
         m->substream[substr].restart_seen = 0;
 
+    /* Set the layout for each substream. When there's more than one, the first
+     * substream is Stereo. Subsequent substreams' layouts are indicated in the
+     * major sync. */
+    if (m->avctx->codec_id == AV_CODEC_ID_MLP) {
+        if ((substr = (mh.num_substreams > 1)))
+            m->substream[0].ch_layout = AV_CH_LAYOUT_STEREO;
+        m->substream[substr].ch_layout = mh.channel_layout_mlp;
+    } else {
+        if ((substr = (mh.num_substreams > 1)))
+            m->substream[0].ch_layout = AV_CH_LAYOUT_STEREO;
+        if (mh.num_substreams > 2)
+            if (mh.channel_layout_thd_stream2)
+                m->substream[2].ch_layout = mh.channel_layout_thd_stream2;
+            else
+                m->substream[2].ch_layout = mh.channel_layout_thd_stream1;
+        m->substream[substr].ch_layout = mh.channel_layout_thd_stream1;
+    }
+
     return 0;
 }