[FFmpeg-user] Overlaying Teletext, getting jerky video

[JULIAN GARDNER]

AS TOLD, I AM REPOSTING THIS HERE

Command line and output, I know im not using a great encoder, but its a 
test so im not bothered about the quality/rate, just the outcome

encoder at encoder:~/ffmpeg$
 ./ffmpeg -threads 4 -txt_page 100 -canvas_size 492x250 -i ../tv2hd.ts 
-filter_complex "[0:s] scale=1280:720 [sub],[0:v][sub] 
overlay,scale=320:-1" -y -f mpegts a.ts
ffmpeg version N-59119-g8a6865f Copyright (c) 2000-2013 the FFmpeg developers
  built on Dec 15 2013 13:05:03 with gcc 4.6 (Ubuntu/Linaro 4.6.3-1ubuntu5)
 
 configuration: --enable-gpl --enable-version3 --enable-nonfree 
--enable-postproc --enable-libfaac --enable-libmp3lame --enable-libx264 
--enable-libzvbi --cc='ccache cc'
  libavutil      52. 58.100 / 52. 58.100
  libavcodec     55. 45.101 / 55. 45.101
  libavformat    55. 22.100 / 55. 22.100
  libavdevice    55.  5.102 / 55.  5.102
  libavfilter     3. 92.100 /  3. 92.100
  libswscale      2.  5.101 /  2.  5.101
  libswresample   0. 17.104 /  0. 17.104
  libpostproc    52.  3.100 / 52.  3.100
[h264 @ 0x2006ca0] non-existing SPS 0 referenced in buffering period
[h264 @ 0x2006ca0] non-existing PPS referenced
[h264 @ 0x2006ca0] non-existing SPS 0 referenced in buffering period
[h264 @ 0x2006ca0] non-existing PPS 0 referenced
[h264 @ 0x2006ca0] decode_slice_header error
[h264 @ 0x2006ca0] no frame!
[mpegts @ 0x2002b20] PES packet size mismatch
Input #0, mpegts, from '../tv2hd.ts':
  Duration: 02:49:18.71, start: 8814.775889, bitrate: 193 kb/s
  Program 6906 
   
 Stream #0:0[0x204]: Video: h264 (High) ([27][0][0][0] / 0x001B), 
yuv420p(tv, bt709), 1280x720 [SAR 1:1 DAR 16:9], 50 fps, 50 tbr, 90k 
tbn, 100 tbc
    Stream #0:1[0x290](dan): Audio: ac3 ([6][0][0][0] / 0x0006), 48000 Hz, 5.1(side), fltp, 448 kb/s
    Stream #0:2[0x242](dan,I100): Subtitle: dvb_teletext ([6][0][0][0] / 0x0006), 492x250
Output #0, mpegts, to 'a.ts':
  Metadata:
    encoder         : Lavf55.22.100
    Stream #0:0: Video: mpeg2video, yuv420p, 320x180 [SAR 1:1 DAR 16:9], q=2-31, 200 kb/s, 90k tbn, 50 tbc (default)
    Stream #0:1(dan): Audio: mp2, 48000 Hz, stereo, s16, 128 kb/s
Stream mapping:
  Stream #0:0 (h264) -> overlay:main (graph 0)
  Stream #0:2 (libzvbi_teletextdec) -> scale (graph 0)
  scale (graph 0) -> Stream #0:0 (mpeg2video)
  Stream #0:1 -> #0:1 (ac3 -> mp2)
Press [q] to stop, [?] for help
[Parsed_overlay_1 @ 0x200a940] [framesync @ 0x200aa08] Buffer queue overflow, dropping.
    Last message repeated 12 times
[Parsed_overlay_1 @ 0x200a940] [framesync @ 0x200aa08] Buffer queue overflow, dropping. drop=0    
    Last message repeated 9 times
[Parsed_overlay_1 @ 0x200a940] [framesync @ 0x200aa08] Buffer queue overflow, dropping.00 drop=0    
    Last message repeated 21 times
[Parsed_overlay_1 @ 0x200a940] [framesync @ 0x200aa08] Buffer queue overflow, dropping.22 drop=0    
    Last message repeated 15 times
[Parsed_overlay_1 @ 0x200a940] [framesync @ 0x200aa08] Buffer queue overflow, dropping.38 drop=0    
    Last message repeated 72 times
[Parsed_overlay_1 @ 0x200a940] [framesync @ 0x200aa08] Buffer queue overflow, dropping.11 drop=0    
    Last message repeated 77 times
[Parsed_overlay_1 @ 0x200a940] [framesync @ 0x200aa08] Buffer queue overflow, dropping.57 drop=0    
    Last message repeated 61 times
[Parsed_overlay_1 @ 0x200a940] [framesync @ 0x200aa08] Buffer queue overflow, dropping.04 drop=0    
    Last message repeated 38 times
[Parsed_overlay_1 @ 0x200a940] [framesync @ 0x200aa08] Buffer queue overflow, dropping.90 drop=0    
    Last message repeated 42 times
[Parsed_overlay_1 @ 0x200a940] [framesync @ 0x200aa08] Buffer queue overflow, dropping.33 drop=0    
    Last message repeated 66 times


Any
 ideas on why frames are being dropped? I really think that there should
 be the correct frames from the teletext engine to keep the overlay 
system running.


joolz