[MEncoder-users] Mencoder skipping frames when encoding from Quicktime ProRes

[Dominic Bird]

Im trying to get a command line setup so that I can encode from pretty
much any video thrown at it to a certain spec. I've been very successful
but when encoding from ProRes encoded video (1080i50) mencoder always
skips frames and I end up with jumpy video. Any ideas? Heres my
command...

 

mencoder -demuxer mov \\xxx\testmovhd.mov -o \\xxx\testmovhd.flv -vf
pp=fd,scale=1280:720 -af channels=2,format=s16le,resample=44100 -mc 0
-ovc x264 -x264encopts
global_header:level_idc=30:bframes=0:bitrate=2048:preset=superfast -oac
faac -faacopts mpeg=4:object=2:br=128:raw -of lavf

 

 

Before I sent this I discovered the problem. The problem is that
Quicktime / Final Cut flags all HD video as variable frame rate. When
mencoder trys to read what frame rate it is it seems to read the minimum
frame rate flag. Here's an example of what is in the file from
MediaInfo. This is fom a 1080i50 DVCPRO HD Quicktime file.

 

Frame rate mode :

Variable

Frame rate :

24.985 fps

Minimum frame rate :

16.667 fps

Maximum frame rate :

25.000 fps

 

You would think it would be safe to use the maximum frame rate but here
is what is extracted from a 23.98 PRORES file.

 

Frame rate mode :

Variable

Frame rate :

24.014 fps

Minimum frame rate :

15.984 fps

Maximum frame rate :

162.000 fps

 

So basically the only thing I can think of doing is reading the frame
rate and rounding it up to 25, 23.98, 29.97.