avformat/mov: read reel_name metadata from tmcd atom

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavformat/mov.c

@@ -1531,6 +1531,26 @@ static int mov_parse_stsd_data(MOVContext *c, AVIOContext *pb,
                 st->codec->flags2 |= CODEC_FLAG2_DROP_FRAME_TIMECODE;
             st->codec->time_base.den = st->codec->extradata[16]; /* number of frame */
             st->codec->time_base.num = 1;
+            if (size > 30) {
+                uint32_t len = AV_RB32(st->codec->extradata + 18); /* name atom length */
+                uint32_t format = AV_RB32(st->codec->extradata + 22);
+                if (format == AV_RB32("name") && (int64_t)size >= (int64_t)len + 18) {
+                    uint16_t str_size = AV_RB16(st->codec->extradata + 26); /* string length */
+                    if (str_size > 0 && size >= (int)str_size + 26) {
+                        char *reel_name = av_malloc(str_size + 1);
+                        if (!reel_name)
+                            return AVERROR(ENOMEM);
+                        memcpy(reel_name, st->codec->extradata + 30, str_size);
+                        reel_name[str_size] = 0; /* Add null terminator */
+                        /* don't add reel_name if emtpy string */
+                        if (*reel_name == 0) {
+                            av_free(reel_name);
+                        } else {
+                            av_dict_set(&st->metadata, "reel_name", reel_name,  AV_DICT_DONT_STRDUP_VAL);
+                        }
+                    }
+                }
+            }
         }
     } else {
         /* other codec type, just skip (rtp, mp4s ...) */