Thanks for reporting your issue. Please make sure these boxes are checked before submitting your issue - thank you!

- [X] I looked for a similar issue and couldn't find any.
- [X] I tried with the latest version of GPAC. Installers available at http://gpac.io/downloads/gpac-nightly-builds/
-  #[X] I give enough information for contributors to reproduce my issue (meaningful title, github labels, platform and compiler, command-line ...). I can share files anonymously with this dropbox: https://www.mediafire.com/filedrop/filedrop_hosted.php?drop=eec9e058a9486fe4e99c33021481d9e1826ca9dbc242a6cfaab0fe95da5e5d95

Detailed guidelines: http://gpac.io/2013/07/16/how-to-file-a-bug-properly/

I'm working on 360 videos using MPEG-DASH-SRD.
Details about my work are discussed in issue #1683.

I'm trying to compute VMAF and PSNR for 360 videos. For which I used avfilter with libvmaf. 
When I calculated vmaf I got 0 vmaf score for most of the frames.I have attached the log for the same.
I'm not sure if there's some issue with my video or I'm calculating vmaf in wrong way.

I used following command.
`gpac -i original.mp4:#ffid=dist -i distorted.mp4:#ffid=ref ffavf::f=[dist][ref]libvmaf=log_path=libvmaf.log @ -o null`

vmaf score 
[libvmaf.log](https://github.com/gpac/gpac/files/6181668/libvmaf.log)


https://user-images.githubusercontent.com/20301133/111981307-81a81e80-8b2d-11eb-84ff-7aad54f850a3.mp4

https://user-images.githubusercontent.com/20301133/111981319-85d43c00-8b2d-11eb-9654-a9d55efcb81a.mp4

This second video (distorted.mp4) can be played with only mp4client,if there's a way to make it compatible with every other video player please let me know.

Also I wanted to calculate psnr and ssim score along with the vmaf for which I used following command but I just got the vmaf score.
`gpac -i original.mp4:#ffid=dist -i distorted.mp4:#ffid=ref  ffavf::f=[dist][ref]libvmaf=log_path=libvmaf.log::psnr=true=log_path=psnr.log @ -o null`



QA of HEVC encoded 360 video | VMAF | PSNR
This is a GitHub Issue
repo:gpac
owner:gpac
Title : QA of HEVC encoded 360 video | VMAF | PSNR
Issue date:

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Thanks for reporting your issue. Please make sure these boxes are checked before submitting your issue - thank you!

- [X] I looked for a similar issue and couldn't find any.
- [X] I tried with the latest version of GPAC. Installers available at http://gpac.io/downloads/gpac-nightly-builds/
-  #[X] I give enough information for contributors to reproduce my issue (meaningful title, github labels, platform and compiler, command-line ...). I can share files anonymously with this dropbox: https://www.mediafire.com/filedrop/filedrop_hosted.php?drop=eec9e058a9486fe4e99c33021481d9e1826ca9dbc242a6cfaab0fe95da5e5d95

Detailed guidelines: http://gpac.io/2013/07/16/how-to-file-a-bug-properly/

I'm working on 360 videos using MPEG-DASH-SRD.
Details about my work are discussed in issue #1683.

I'm trying to compute VMAF and PSNR for 360 videos. For which I used avfilter with libvmaf. 
When I calculated vmaf I got 0 vmaf score for most of the frames.I have attached the log for the same.
I'm not sure if there's some issue with my video or I'm calculating vmaf in wrong way.

I used following command.
`gpac -i original.mp4:#ffid=dist -i distorted.mp4:#ffid=ref ffavf::f=[dist][ref]libvmaf=log_path=libvmaf.log @ -o null`

vmaf score 
[libvmaf.log](https://github.com/gpac/gpac/files/6181668/libvmaf.log)


https://user-images.githubusercontent.com/20301133/111981307-81a81e80-8b2d-11eb-84ff-7aad54f850a3.mp4

https://user-images.githubusercontent.com/20301133/111981319-85d43c00-8b2d-11eb-9654-a9d55efcb81a.mp4

This second video (distorted.mp4) can be played with only mp4client,if there's a way to make it compatible with every other video player please let me know.

Also I wanted to calculate psnr and ssim score along with the vmaf for which I used following command but I just got the vmaf score.
`gpac -i original.mp4:#ffid=dist -i distorted.mp4:#ffid=ref  ffavf::f=[dist][ref]libvmaf=log_path=libvmaf.log::psnr=true=log_path=psnr.log @ -o null`



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