mpegts: Allow custom max resync size

libavformat/mpegts.c

@@ -126,6 +126,8 @@ struct MpegTSContext {
     /** to detect seek */
     int64_t last_pos;
 
+    int resync_size;
+
     /******************************************/
     /* private mpegts data */
     /* scan context */
@@ -137,7 +139,23 @@ struct MpegTSContext {
     MpegTSFilter *pids[NB_PID_MAX];
 };
 
+#define MPEGTS_OPTIONS \
+    { "resync_size",   "Size limit for looking up a new syncronization.", offsetof(MpegTSContext, resync_size), AV_OPT_TYPE_INT,  { .i64 =  MAX_RESYNC_SIZE}, 0, INT_MAX,  AV_OPT_FLAG_DECODING_PARAM }
+
 static const AVOption options[] = {
+    MPEGTS_OPTIONS,
+    { NULL },
+};
+
+static const AVClass mpegts_class = {
+    .class_name = "mpegts demuxer",
+    .item_name  = av_default_item_name,
+    .option     = options,
+    .version    = LIBAVUTIL_VERSION_INT,
+};
+
+static const AVOption raw_options[] = {
+    MPEGTS_OPTIONS,
     { "compute_pcr",   "Compute exact PCR for each transport stream packet.",
           offsetof(MpegTSContext, mpeg2ts_compute_pcr), AV_OPT_TYPE_INT,
           { .i64 = 0 }, 0, 1,  AV_OPT_FLAG_DECODING_PARAM },
@@ -151,7 +169,7 @@ static const AVOption options[] = {
 static const AVClass mpegtsraw_class = {
     .class_name = "mpegtsraw demuxer",
     .item_name  = av_default_item_name,
-    .option     = options,
+    .option     = raw_options,
     .version    = LIBAVUTIL_VERSION_INT,
 };
 
@@ -1805,10 +1823,11 @@ static int handle_packet(MpegTSContext *ts, const uint8_t *packet)
  * get_packet_size() ?) */
 static int mpegts_resync(AVFormatContext *s)
 {
+    MpegTSContext *ts = s->priv_data;
     AVIOContext *pb = s->pb;
     int c, i;
 
-    for (i = 0; i < MAX_RESYNC_SIZE; i++) {
+    for (i = 0; i < ts->resync_size; i++) {
         c = avio_r8(pb);
         if (pb->eof_reached)
             return AVERROR_EOF;
@@ -2285,6 +2304,7 @@ AVInputFormat ff_mpegts_demuxer = {
     .read_seek      = read_seek,
     .read_timestamp = mpegts_get_pcr,
     .flags          = AVFMT_SHOW_IDS | AVFMT_TS_DISCONT,
+    .priv_class     = &mpegts_class,
 };
 
 AVInputFormat ff_mpegtsraw_demuxer = {