[FFmpeg-user] Pullup old MPEG-2

[Carl Eugen Hoyos]

Paul B Mahol <onemda <at> gmail.com> writes:

> 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.

Carl Eugen