[FFmpeg-user] psnr range

[Carl Eugen Hoyos]

Am Di., 25. Juni 2019 um 22:00 Uhr schrieb Le Chiffre
<le_chiffre at bondvillian.com>:
>
> I have found that the psnr result from the psnr filter, vs the psnr that is
> part of libvmaf (calling it via ffmpeg), differs slightly, generally under
> 1%. I suppose the implementation is different.
>
> This seems ok. What is more interesting is that libvmaf-psnr clearly has a
> range up to 60 whereas the ffmpeg psnr seems to go past 90.
>
> 1. What's the full range of ffmpeg's psnr value?

The source code contains the following line in vf_psnr.c:
return 10.0 * log10(pow_2(max) / (mse / nb_frames))
so a likely range is 0-100

Carl Eugen