[FFmpeg-devel] [PATCH] make stream-switching work with MOV demuxer

[Reimar Döffinger]

On Tue, Jun 23, 2009 at 01:06:58PM -0700, Baptiste Coudurier wrote:
> The other patch looks ok, and it is not uglier IMHO, it will allow sc =
> msc removal since sc == st->priv_data, and sc->ffindex will no longer be
> needed.

Ok, let's get that part out of the way, see attached patch.
Personally I'd even suggest making a
AVIndexEntry *find_next_sample(AVFormatContext *s, AVStream **st);
or similar that contains the whole for loop, making mov_read_packet
a bit more self-documenting.
-------------- next part --------------
Index: libavformat/mov.c
===================================================================
--- libavformat/mov.c	(revision 19256)
+++ libavformat/mov.c	(working copy)
@@ -1982,14 +1982,15 @@
     MOVContext *mov = s->priv_data;
     MOVStreamContext *sc = 0;
     AVIndexEntry *sample = 0;
+    AVStream *st = NULL;
     int64_t best_dts = INT64_MAX;
     int i, ret;
  retry:
     for (i = 0; i < s->nb_streams; i++) {
-        AVStream *st = s->streams[i];
-        MOVStreamContext *msc = st->priv_data;
-        if (st->discard != AVDISCARD_ALL && msc->pb && msc->current_sample < st->nb_index_entries) {
-            AVIndexEntry *current_sample = &st->index_entries[msc->current_sample];
+        AVStream *avst = s->streams[i];
+        MOVStreamContext *msc = avst->priv_data;
+        if (avst->discard != AVDISCARD_ALL && msc->pb && msc->current_sample < avst->nb_index_entries) {
+            AVIndexEntry *current_sample = &avst->index_entries[msc->current_sample];
             int64_t dts = av_rescale(current_sample->timestamp, AV_TIME_BASE, msc->time_scale);
             dprintf(s, "stream %d, sample %d, dts %"PRId64"\n", i, msc->current_sample, dts);
             if (!sample || (url_is_streamed(s->pb) && current_sample->pos < sample->pos) ||
@@ -1999,7 +2000,7 @@
                   (FFABS(best_dts - dts) > AV_TIME_BASE && dts < best_dts)))))) {
                 sample = current_sample;
                 best_dts = dts;
-                sc = msc;
+                st = avst;
             }
         }
     }
@@ -2012,6 +2013,7 @@
         dprintf(s, "read fragments, offset 0x%llx\n", url_ftell(s->pb));
         goto retry;
     }
+    sc = st->priv_data;
     /* must be done just before reading, to avoid infinite loop on sample */
     sc->current_sample++;
     if (url_fseek(sc->pb, sample->pos, SEEK_SET) != sample->pos) {
@@ -2045,7 +2047,6 @@
         if (sc->wrong_dts)
             pkt->dts = AV_NOPTS_VALUE;
     } else {
-        AVStream *st = s->streams[sc->ffindex];
         int64_t next_dts = (sc->current_sample < st->nb_index_entries) ?
             st->index_entries[sc->current_sample].timestamp : st->duration;
         pkt->duration = next_dts - pkt->dts;