[FFmpeg-user] Pullup old MPEG-2

[Rens Dijkshoorn]

> 
>> On 12/22/15, Carl Eugen Hoyos <cehoyos <at> ag.or.at> wrote: 
>> > llee782 <llee040 <at> sbcglobal.net> writes: 
>> > 
>> >> Carl Eugen Hoyos wrote 
>> >> > Do you believe that the input video you provided is 
>> >> > telecined? 
>> >> 
>> >> I do. 
>> > 
>> > Although I live in PAL-land, I have often dealt with 
>> > telecined video when trying to reproduce bug reports. 
>> > As a long-time FFmpeg developer, allow me to assure 
>> > you that the video you uploaded is not telecined. 
>> 
>> Then why I see tipical telecine pattern? 
> 
> $ md5sum 2024_telecine_source.mpg 
> 9f54fc2f71c43a0de141c18be80556b7 2024_telecine_source.mpg 
> $ ffmpeg -i 2024_telecine_source.mpg -vf idet -f null - 
> ffmpeg version N-77432-gc0f67e1 Copyright (c) 2000-2015 the FFmpeg developers 
> built with gcc 4.7 (SUSE Linux) 
> configuration: --enable-gpl 
> libavutil 55. 11.100 / 55. 11.100 
> libavcodec 57. 19.100 / 57. 19.100 
> libavformat 57. 20.100 / 57. 20.100 
> libavdevice 57. 0.100 / 57. 0.100 
> libavfilter 6. 21.100 / 6. 21.100 
> libswscale 4. 0.100 / 4. 0.100 
> libswresample 2. 0.101 / 2. 0.101 
> libpostproc 54. 0.100 / 54. 0.100 
> Input #0, mpeg, from '2024_telecine_source.mpg': 
> Duration: 00:00:14.05, start: 1.000000, bitrate: 6918 kb/s 
> Stream #0:0[0x1e0]: Video: mpeg2video (Main), yuv420p(tv), 720x480 [SAR 
> 8:9 DAR 4:3], Closed Captions, max. 7890 kb/s, 29.97 fps, 29.97 tbr, 90k 
> tbn, 59.94 tbc 
> Stream #0:1[0x80]: Audio: ac3, 48000 Hz, 5.1(side), fltp, 448 kb/s 
> Output #0, null, to 'pipe:': 
> Metadata: 
> encoder : Lavf57.20.100 
> Stream #0:0: Video: wrapped_avframe, yuv420p, 720x480 [SAR 8:9 DAR 4:3], 
> q=2-31, 200 kb/s, 29.97 fps, 29.97 tbn, 29.97 tbc 
> Metadata: 
> encoder : Lavc57.19.100 wrapped_avframe 
> Stream #0:1: Audio: pcm_s16le, 48000 Hz, 5.1(side), s16, 4608 kb/s 
> Metadata: 
> encoder : Lavc57.19.100 pcm_s16le 
> Stream mapping: 
> Stream #0:0 -> #0:0 (mpeg2video (native) -> wrapped_avframe (native)) 
> Stream #0:1 -> #0:1 (ac3 (native) -> pcm_s16le (native)) 
> Press [q] to stop, [?] for help 
> [mpeg2video @ 0x2747ee0] ac-tex damaged at 42 0 
> [mpeg2video @ 0x2747ee0] Warning MVs not available 
> [mpeg2video @ 0x2747ee0] concealing 1350 DC, 1350 AC, 1350 MV errors in I frame 
> [ac3 @ 0x26afd40] incomplete frame 
> frame= 335 fps=0.0 q=-0.0 Lsize=N/A time=00:00:13.98 bitrate=N/A speed=41.6x 
> video:157kB audio:7758kB subtitle:0kB other streams:0kB global headers:0kB 
> muxing overhead: unknown 
> [Parsed_idet_0 @ 0x26b38c0] Repeated Fields: Neither: 335 Top: 0 
> Bottom: 0 
> [Parsed_idet_0 @ 0x26b38c0] Single frame detection: TFF: 0 BFF: 0 
> Progressive: 334 Undetermined: 1 
> [Parsed_idet_0 @ 0x26b38c0] Multi frame detection: TFF: 0 BFF: 0 
> Progressive: 335 Undetermined: 0 
> 
> Visually, I was also unable to see an interlaced pattern 
> (which is a requirement for telecined video) in any of the 
> 335 frames. 
> 
> The video was recorded at (approximately) 24 frames per 
> second and soft telecine was used to allow playback on 
> NTSC hardware. FFmpeg (luckily) ignores soft telecine 
> and treats the video as progressive. 
> 
> I don't know why the following commands produce very 
> different output: 
> ffmpeg -i 2024_telecine_source.mpg -vf pullup -qscale 2 out.avi 
> mencoder 2024_telecine_source.mpg -vf pullup -oac lavc -ovc lavc 
> -lavcopts vqscale=2 -o out.avi 
> There may be a problem with FFmpeg's pullup port. 
> 

Hi, 

just had a look at the video same conclusion no fields no 
reverse telecine possible, but with a frame rate of 23.98 
( Quicktime 7) i would not expect to see any field information 
anyway. ( QuicktimeX @ 29,97 honours the soft flag ) 

The soft telecine will make the player to apply a telecine 
pattern to the playback at NTSC frame rates. 

In my opinon the only thing thats needs to be done is to 
remove the soft-telecine flag from the mpg file to playback at the 
orginal frame rate. 

ffmpeg -r 24 -i 2024_telecine_source.mpg -c copy 2024_telecine_source.mov 

Both Quicktime7 and QuicktimeX now play at 23.85fps with the durartion 
unchanged still at 14 sec. 



Regards 

Rens