lavf/matroskadec: Get sample size from private data

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

libavformat/matroskadec.c

@@ -1891,18 +1891,24 @@ static int matroska_parse_tracks(AVFormatContext *s)
                    /* Normally 36, but allow noncompliant private data */
                    && (track->codec_priv.size >= 32)
                    && (track->codec_priv.data)) {
+            uint16_t sample_size;
             int ret = get_qt_codec(track, &fourcc, &codec_id);
             if (ret < 0)
                 return ret;
+            sample_size = AV_RB16(track->codec_priv.data + 26);
             if (fourcc == 0) {
-                if (track->audio.bitdepth == 8) {
+                if (sample_size == 8) {
                     fourcc = MKTAG('r','a','w',' ');
                     codec_id = ff_codec_get_id(ff_codec_movaudio_tags, fourcc);
-                } else if (track->audio.bitdepth == 16) {
+                } else if (sample_size == 16) {
                     fourcc = MKTAG('t','w','o','s');
                     codec_id = ff_codec_get_id(ff_codec_movaudio_tags, fourcc);
                 }
             }
+            if ((fourcc == MKTAG('t','w','o','s') ||
+                    fourcc == MKTAG('s','o','w','t')) &&
+                    sample_size == 8)
+                codec_id = AV_CODEC_ID_PCM_S8;
         } else if (!strcmp(track->codec_id, "V_QUICKTIME") &&
                    (track->codec_priv.size >= 21)          &&
                    (track->codec_priv.data)) {