low-complexity Bink file seeking

Originally committed as revision 22022 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavformat/bink.c

@@ -241,6 +241,19 @@ static int read_packet(AVFormatContext *s, AVPacket *pkt)
     return 0;
 }
 
+static int read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
+{
+    BinkDemuxContext *bink = s->priv_data;
+    AVStream *vst = s->streams[0];
+
+    /* seek to the first frame */
+    url_fseek(s->pb, vst->index_entries[0].pos, SEEK_SET);
+    bink->video_pts = 0;
+    memset(bink->audio_pts, 0, sizeof(bink->audio_pts));
+    bink->current_track = -1;
+    return 0;
+}
+
 AVInputFormat bink_demuxer = {
     "bink",
     NULL_IF_CONFIG_SMALL("Bink"),
@@ -248,4 +261,6 @@ AVInputFormat bink_demuxer = {
     probe,
     read_header,
     read_packet,
+    NULL,
+    read_seek,
 };