MOV: Fix old-style muxed raw-audio data.

This patch fixes the sample from trac issue #522.
The issue is that the mov demuxer insists on using its
calculated sample_size (which is nonsense for old-style tracks)
instead of the one encoded in the track.
The old raw audio code should be using the value in stsz, because
the size of a single sample never makes sense for the size of
a full audio packet, whereas the new code will multiply the
sample size by the chunk size, so it should use the calculated value.

Signed-off-by: Reimar Döffinger <Reimar.Doeffinger@gmx.de>

libavformat/isom.h

@@ -103,7 +103,8 @@ typedef struct MOVStreamContext {
     unsigned *stps_data;  ///< partial sync sample for mpeg-2 open gop
     int ctts_index;
     int ctts_sample;
-    unsigned int sample_size;
+    unsigned int sample_size; ///< may contain value calculated from stsd or value from stsz atom
+    unsigned int alt_sample_size; ///< always contains sample size from stsz atom
     unsigned int sample_count;
     int *sample_sizes;
     unsigned int keyframe_count;

libavformat/mov.c

@@ -1644,6 +1644,7 @@ static int mov_read_stsz(MOVContext *c, AVIOContext *pb, MOVAtom atom)
         sample_size = avio_rb32(pb);
         if (!sc->sample_size) /* do not overwrite value computed in stsd */
             sc->sample_size = sample_size;
+        sc->alt_sample_size = sample_size;
         field_size = 32;
     } else {
         sample_size = 0;
@@ -1874,7 +1875,7 @@ static void mov_build_index(MOVContext *mov, AVStream *st)
                 }
                 if (keyframe)
                     distance = 0;
-                sample_size = sc->sample_size > 0 ? sc->sample_size : sc->sample_sizes[current_sample];
+                sample_size = sc->alt_sample_size > 0 ? sc->alt_sample_size : sc->sample_sizes[current_sample];
                 if (sc->pseudo_stream_id == -1 ||
                    sc->stsc_data[stsc_index].id - 1 == sc->pseudo_stream_id) {
                     AVIndexEntry *e = &st->index_entries[st->nb_index_entries++];