* enabling seek in raw DV files

   * generic DV demuxer now sets correct pts for every packet

Originally committed as revision 2919 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavformat/dv.c

@@ -33,6 +33,8 @@ struct DVDemuxContext {
     AVStream*        ast[2];       
     AVPacket         audio_pkt[2];
     int              ach;
+    int              frames;
+    uint64_t         abytes;
 };
 
 struct DVMuxContext {
@@ -720,6 +722,8 @@ DVDemuxContext* dv_init_demux(AVFormatContext *s)
     c->fctx = s;
     c->ast[1] = NULL;
     c->ach = 0;
+    c->frames = 0;
+    c->abytes = 0;
     c->audio_pkt[0].size = 0;
     c->audio_pkt[1].size = 0;
     
@@ -732,6 +736,8 @@ DVDemuxContext* dv_init_demux(AVFormatContext *s)
    
     s->ctx_flags |= AVFMTCTX_NOHEADER; 
     
+    av_set_pts_info(s, 64, 1, 30000);
+    
     return c;
     
 fail:
@@ -770,8 +776,9 @@ int dv_produce_packet(DVDemuxContext *c, AVPacket *pkt,
                       uint8_t* buf, int buf_size)
 {
     int size, i;
+    const DVprofile* sys = dv_frame_profile(buf);
    
-    if (buf_size < 4 || buf_size < dv_frame_profile(buf)->frame_size)
+    if (buf_size < 4 || buf_size < sys->frame_size)
         return -1;   /* Broken frame, or not enough data */
 
     /* Queueing audio packet */
@@ -782,8 +789,11 @@ int dv_produce_packet(DVDemuxContext *c, AVPacket *pkt,
        if (av_new_packet(&c->audio_pkt[i], size) < 0)
            return AVERROR_NOMEM;
        c->audio_pkt[i].stream_index = c->ast[i]->index;
+       c->audio_pkt[i].pts = c->abytes * 30000*8 / c->ast[i]->codec.bit_rate;
+       c->audio_pkt[i].flags |= PKT_FLAG_KEY;
     }
     dv_extract_audio(buf, c->audio_pkt[0].data, c->audio_pkt[1].data);
+    c->abytes += size;
     
     /* Now it's time to return video packet */
     size = dv_extract_video_info(c, buf);
@@ -793,10 +803,21 @@ int dv_produce_packet(DVDemuxContext *c, AVPacket *pkt,
     pkt->size     = size; 
     pkt->flags   |= PKT_FLAG_KEY;
     pkt->stream_index = c->vst->id;
+    pkt->pts      = c->frames * sys->frame_rate_base * (30000/sys->frame_rate);
+    
+    c->frames++;
 
     return size;
 }
                            
+int64_t dv_frame_offset(DVDemuxContext *c, int64_t timestamp)
+{
+    const DVprofile* sys = dv_codec_profile(&c->vst->codec);
+
+    return sys->frame_size * ((timestamp * sys->frame_rate) / 
+	                      (AV_TIME_BASE * sys->frame_rate_base));
+}
+
 /************************************************************
  * Implementation of the easiest DV storage of all -- raw DV.
  ************************************************************/
@@ -837,6 +858,13 @@ static int dv_read_packet(AVFormatContext *s, AVPacket *pkt)
     return size;
 }
 
+static int dv_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp)
+{
+    RawDVContext *c = s->priv_data;
+
+    return url_fseek(&s->pb, dv_frame_offset(c->dv_demux, timestamp), SEEK_SET);
+}
+
 static int dv_read_close(AVFormatContext *s)
 {
     RawDVContext *c = s->priv_data;
@@ -892,6 +920,7 @@ static AVInputFormat dv_iformat = {
     dv_read_header,
     dv_read_packet,
     dv_read_close,
+    dv_read_seek,
     .extensions = "dv",
 };
 

libavformat/dv1394.c

@@ -43,8 +43,6 @@ struct dv1394_data {
     int avail;  /* Number of frames available for reading */
     int done;   /* Number of completed frames */
 
-    int64_t pts;  /* Current timestamp */
-
     DVDemuxContext* dv_demux; /* Generic DV muxing/demuxing context */
 };
 
@@ -121,8 +119,6 @@ static int dv1394_read_header(AVFormatContext * context, AVFormatParameters * ap
         goto failed;
     }
 
-    av_set_pts_info(context, 48, 1, 1000000);
-
     if (dv1394_start(dv) < 0)
         goto failed;
 
@@ -140,7 +136,7 @@ static int dv1394_read_packet(AVFormatContext *context, AVPacket *pkt)
 
     size = dv_get_packet(dv->dv_demux, pkt);
     if (size > 0)
-        goto out;
+        return size;
 
     if (!dv->avail) {
         struct dv1394_status s;
@@ -209,10 +205,7 @@ restart_poll:
 			     DV1394_PAL_FRAME_SIZE);
     dv->index = (dv->index + 1) % DV1394_RING_FRAMES;
     dv->done++; dv->avail--;
-    dv->pts = av_gettime() & ((1LL << 48) - 1);
     
-out:
-    pkt->pts = dv->pts;
     return size;
 }