[FFmpeg-user] repeat a frame

Mark Filipak (ffmpeg) markfilipak at bog.us
Fri Mar 5 01:06:27 EET 2021

On 2021-03-04 11:02, Peter White wrote:
> On 03.03.21 23:57, Mark Filipak (ffmpeg) wrote:
>> On 2021-03-03 11:30, Mark Filipak (ffmpeg) wrote:
>> I've tried transcoding a 2:21:19 movie via this script:
>> SET codecs=-codec:v libx265 -x265-params crf=16:qcomp=1.00 -codec:a copy -codec:s copy -dn
> FWIW I could not help but notice that you effectivly degrade crf to
> constant quantizer. Might as well use:
> -x265-params qp=16
> See https://x265.readthedocs.io/en/master/cli.html#cmdoption-qcomp
> Peter

Thanks, Peter!

What these directives actually mean is a bit hazy to me.

Is there a functional relationship between 'crf' and 'qcomp'?
Perhaps qp = crf/qcomp?

What would the units be?
'crf' would be frames/s I suppose. The others: ????? ...something to do with quantizing and 
compressing, but I don't have much of a clue regarding what is quantized, how it is quantized and 
what is compressed.

Basically, I understand processes via the input and output units. Without units, I don't know what a 
process does. It just becomes tossed word-salad.

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