[FFmpeg-devel] DVB Subtitles

[JULIAN GARDNER]

----- Original Message -----
> From: Nicolas George <george at nsup.org>
> To: FFmpeg development discussions and patches <ffmpeg-devel at ffmpeg.org>
> Cc: 
> Sent: Wednesday, 4 December 2013, 12:27
> Subject: Re: [FFmpeg-devel] DVB Subtitles
> 
> Le quartidi 14 frimaire, an CCXXII, JULIAN GARDNER a écrit :
>>  Why as this is a development problem!
> 
> I see no patch.
> 
>>  The code needs changing to take into account that what is happening now is
>>  wrong, 
> 
> This is not proven, since you did not provide the full console output.
> 
>>  So again why is this a -user thread?
> 
> Read the mailing lists descriptions. EOT for me.
> 
> Regards,
> 
> -- 
>   Nicolas George
> 
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> ffmpeg-devel at ffmpeg.org
> http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
>

god i love this mailing list EOT ha ha ha

Ok no patch BECAUSE i wanted feedback before starting to patch DVB Subs again.

If someone has a better idea then please join the conversation.

Console output so you can see the problem

2013-12-04_11:44:06.98894 ffmpeg version N-57168-g54180a5 Copyright (c) 2000-2013 the FFmpeg developers
2013-12-04_11:44:06.98897   built on Oct 15 2013 23:18:59 with gcc 4.6.1 (Ubuntu/Linaro 4.6.1-9ubuntu3)
2013-12-04_11:44:06.98897   configuration: --enable-gpl --enable-version3 --enable-nonfree --enable-postproc --enable-libfaac --enable-libmp3lame --enable-libx264 --enable-libzvbi --cc='ccache cc'
2013-12-04_11:44:06.98900   libavutil      52. 46.101 / 52. 46.101
2013-12-04_11:44:06.98901   libavcodec     55. 36.100 / 55. 36.100
2013-12-04_11:44:06.98901   libavformat    55. 19.102 / 55. 19.102
2013-12-04_11:44:06.98902   libavdevice    55.  4.100 / 55.  4.100
2013-12-04_11:44:06.98902   libavfilter     3. 88.101 /  3. 88.101
2013-12-04_11:44:06.98902   libswscale      2.  5.101 /  2.  5.101
2013-12-04_11:44:06.98903   libswresample   0. 17.103 /  0. 17.103
2013-12-04_11:44:06.98903   libpostproc    52.  3.100 / 52.  3.100
2013-12-04_11:44:10.27985 Input #0, mpegts, from 'udp://225.173.0.116:1234?reuse&fifo_size=50000':
2013-12-04_11:44:10.27986   Duration: N/A, start: 43877.822556, bitrate: 704 kb/s
2013-12-04_11:44:10.27987   Program 1039 
2013-12-04_11:44:10.27987     Stream #0:0[0x429]: 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
2013-12-04_11:44:10.27989     Stream #0:1[0xc67](nor): Audio: mp2 ([4][0][0][0] / 0x0004), 48000 Hz, stereo, s16p, 256 kb/s
2013-12-04_11:44:10.27989     Stream #0:2[0xfc3](nor): Audio: ac3 ([6][0][0][0] / 0x0006), 48000 Hz, stereo, fltp, 448 kb/s
2013-12-04_11:44:10.27990     Stream #0:3[0x17e4](nor,I100): Subtitle: dvb_teletext ([6][0][0][0] / 0x0006)
2013-12-04_11:44:10.27991     Stream #0:4[0x19ca](nor): Subtitle: dvb_subtitle ([6][0][0][0] / 0x0006)
2013-12-04_11:44:10.27991     Stream #0:5[0x19cb](nor): Subtitle: dvb_subtitle ([6][0][0][0] / 0x0006) (hearing impaired)
2013-12-04_11:44:10.28027 [mpegts @ 0x3231f80] sub2video: using 1280x720 canvas
2013-12-04_11:44:10.28875 [libx264 @ 0x331c4a0] VBV maxrate unspecified, assuming CBR
2013-12-04_11:44:10.28877 [libx264 @ 0x331c4a0] using SAR=1/1
2013-12-04_11:44:10.28937 [libx264 @ 0x331c4a0] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX
2013-12-04_11:44:10.29243 [libx264 @ 0x331c4a0] profile High, level 3.0
2013-12-04_11:44:10.30140 Output #0, mpegts, to 'udp://225.170.22.160:1234?pkt_size=1316;buffer_size=1048576':
2013-12-04_11:44:10.30143   Metadata:
2013-12-04_11:44:10.30144     encoder         : Lavf55.19.102
2013-12-04_11:44:10.30145     Stream #0:0: Video: h264 (libx264), yuv420p, 640x360 [SAR 1:1 DAR 16:9], q=-1--1, 1150 kb/s, 90k tbn, 25 tbc
2013-12-04_11:44:10.30145     Stream #0:1(nor): Audio: aac (libfaac), 32000 Hz, stereo, s16, 128 kb/s
2013-12-04_11:44:10.30146 Stream mapping:
2013-12-04_11:44:10.30146   Stream #0:0 (h264) -> overlay:main (graph 0)
2013-12-04_11:44:10.30147   Stream #0:4 (dvbsub) -> scale (graph 0)
2013-12-04_11:44:10.30147   scale (graph 0) -> Stream #0:0 (libx264)
2013-12-04_11:44:10.30148   Stream #0:1 -> #0:1 (mp2 -> libfaac)
2013-12-04_11:44:10.30148 Press [q] to stop, [?] for help
2013-12-04_11:44:10.31000 [h264 @ 0x72d1f80] Missing reference picture, default is 0
2013-12-04_11:44:10.31003 [h264 @ 0x72d1f80] decode_slice_header error
2013-12-04_11:44:10.31465 [h264 @ 0x73f4000] reference picture missing during reorder
2013-12-04_11:44:10.31468 [h264 @ 0x73f4000] Missing reference picture, default is 65764
2013-12-04_11:44:10.31647 [h264 @ 0x74629e0] mmco: unref short failure
2013-12-04_11:44:10.32402 [h264 @ 0x761d160] mmco: unref short failure
2013-12-04_11:44:10.33551 [mp2 @ 0x3256e20] Header missing
2013-12-04_11:44:10.33554 Error while decoding stream #0:1: Invalid data found when processing input
[dvbsub @ 0x3258e80] DVB parse packet pts=eb6c2264, lpts=0, cpts=eb6c2264:kbits/s dup=24 drop=162    bits/s dup=24 drop=24    
2013-12-04_11:44:14.28019 [dvbsub @ 0x3258e80] DVBsubs 714769 714769
^Came=  345 fps= 35 q=24.0 size=    1788kB time=00:00:12.66 bitrate=1156.6kbits/s dup=24 drop=316    bits/s dup=24 drop=180    

So as you see the canvas is being set to 1280x720 where as the subtitles are sized for a 720x576 screen.
>>2013-12-04_11:44:10.28027 [mpegts @ 0x3231f80] sub2video: using 1280x720 canvas

There is no DDS so the subtitles are draw in the top left corner and when overlayed over the live video are in the wrong place and small compared to the video.

So my 1st idea is to change the way we set the canvas size, in this case it would be based on 720x576 as there is no DDS.

Then the user can rescale his to the real video size, which would make the size and position be correct

joolz