[FFmpeg-user] Best settings for FFV1

[Etienne Desautels]

Hi,

On 2015-09-18, at 03:36, MrNice wrote:
> 
> I don't want to interfere but only to understand the parameters.
> 2nd link, FFv1 results GOP=1 vs. GOP=300
> 
> Documentation says:
> Slices 	-slices 	4, 6, 9, 12, 16, 24, 30 	Each frame is split into this
> number of slices. This affects multithreading performance, as well as
> filesize: Increasing the number of slices might speed up performance,
> but also increases the filesize.
> 
> What I understand in the result, ie: first line
> v3c11s4: -16.68% means the resulting file is smaller by this value
> compared to the original
> v3c11s30: -17.33% means the resulting file is smaller by this value
> compared to the original
> 
> Conclusion: s30 has a smaller filesize than with s4 (for all the lines)
> => opposite what says the documentation.
> 
> Am I right?

I think your looking at the wrong test suite. You need to check the one under "Size difference", not under "GOP difference". Under "Size difference" you will see that files created with 4 slices are smaller than with 30 slices.


> BTW what are the default values of all these parameters in the first
> link? I can't find any user documentation, I mean not too hard to
> understand.

I don't know either what are the default. We should probably check in the source code...

Regards,
Etienne Desautels