add support for more native ffmpeg quality metrics

[richardpl]

There is now also vif (Visual Information Fidelity), and soon identity and msad (Mean Sum of Squared Differences).

They also supports slice threading and timeline (calculating quality metrics only for some frame ranges),

[slhck]

Thanks for the info! I'll probably add an option to calculate them in addition ot the default ones, like for VMAF.

[slhck]

VIF is now implemented since version 2.0.

[richardpl]

Cool.

[ls-milkyway]

Now ffmpeg ...i guess also supports dssim & ms_ssim

[slhck]

@ls-milkyway Why do you think FFmpeg supports DSSIM? Note that VMAF already includes an MS-SSIM computation.

[ls-milkyway]

@ls-milkyway Why do you think FFmpeg supports DSSIM? Note that VMAF already includes an MS-SSIM computation.

I mean you can now build ffmpeg with DSSIM...yep MS-SSIM is included; example: ffmpeg -i distorted.mpg -i reference.mpg -lavfi libvmaf='feature=name=ms_ssim' -f null -

[ls-milkyway]

Please Note: You can add/remove support for more native ffmpeg quality metrics...but please do not change the JSON output structure as I am using it extensively as an input to another program....thanks

[slhck]

@ls-milkyway Why do you think FFmpeg supports DSSIM? Note that VMAF already includes an MS-SSIM computation.

I mean you can now build ffmpeg with DSSIM...yep MS-SSIM is included; example: ffmpeg -i distorted.mpg -i reference.mpg -lavfi libvmaf='feature=name=ms_ssim' -f null -

That seems to be a third party addon not provided by FFmpeg itself.

Please Note: You can add/remove support for more native ffmpeg quality metrics...but please do not change the JSON output structure as I am using it extensively as an input to another program....thanks

Sure, I have experienced such problems myself and I'll promise not to change it! I will get back to this issue (and a few other VMAF-related problems) later in May.

[ls-milkyway]

That seems to be a third party addon not provided by FFmpeg itself.

Yep, but I guess MS-SSIM is better evaluation than SSIM OR DSSIM...hence you can include MS-SSIM instead of SSIM OR DSSIM. As I am not an expert regarding video quality evaluation algorithms ....just saw some articles....so it's up to you to decide. Thanks.

[slhck]

You can get MS-SSIM through VMAF (https://github.com/Netflix/vmaf/blob/master/libvmaf/src/feature/ms_ssim.c), so it should be possible to enable it. I will have to add support to map the respective CLI options though.

[slhck]

Note that MS-SSIM evaluation is now possible starting with version 3.x of this program. See the --vmaf-features option as explained in the README.