[FFmpeg-user] Confusion about fieldmatch, decimate and framerate (now with yadif)

Nicholas Robbins nickrobbins at yahoo.com
Tue Dec 10 03:44:19 CET 2013

> On Sunday, December 8, 2013 11:19 PM, L. Lee <llee040 at sbcglobal.net> wrote:

> > On 12/8/13, 8:24 AM, "Nicholas Robbins" <nickrobbins at yahoo.com> 
> wrote:
>>>  On Sunday, December 8, 2013 3:43 AM, L. Lee 
> <llee040 at sbcglobal.net>
>>> wrote:
>>>  > I didn¹t access your video, please tell me how. In the meantime, I
>>> used
>>>  your process to rip a DVD so I could try some things. I couldn¹t use
>>> .mkv
>>>  as the name extension of the source file, but once I changed it to
>>> .mpg, I
>>>  could use the following. The output is OK from beginning to end even
>>> when
>>>  I performed it on the full 90-minute title. Mine was an old 4X3 source.
>> I don't know how you can get access to incoming, but thanks for the 
> shot.
>> My method works for most dvds, this one source is the exception rather
>> than the rule.
>>>  ffmpeg -y -i Œdd-vob-short.mpg' -map 0:0 -map 0:1 -vf
>>>  "fieldmatch=order=tff:combmatch=none,fps=fps=24000/1001" 
> -pix_fmt
>>>  yuv420p
>>>  -c:v libx264 -preset slower -tune film -crf 18 -x264opts
>>>  keyint=40:bitrate=2100:qpmin=8:qpmax=38:qpstep=4 -c:a:0 libfaac -b:a:0
>>>  256k 'dd-vob-short.detelecine.m4v'
>> IIUC, combmatch=none will label no frames as interlaced. So you wouldn't
>> get any errors like I am getting no matter what. I added that option to
>> my command and it didn't complain anymore, but it did still produce
>> interlaced frames.
>> I tried changing the extension to mpg and I had the same output as
>> before. I had assumed ffmpeg was smarter than that.
> I don’t think the command will be of any use whatsoever without the
> conversion to 24 fps (fps=fps=24000/1001). No interlaced frames remain
> when you use that, do they?

The 'decimate' filter after fieldmatch would take care of the frame rate coversion, but it just throws out the extra frame, so it wouldn't change the fact that fieldmatch was labeling frames as interlaced, but yadif wasn't deinterlacing them.

> Laine
> _______________________________________________
> ffmpeg-user mailing list
> ffmpeg-user at ffmpeg.org
> http://ffmpeg.org/mailman/listinfo/ffmpeg-user

More information about the ffmpeg-user mailing list