Using X265 Compression

[Dor Ma'ayan]

Hi, I would like to use x265 compression for a research I do. For that, I have a video which every second frame of it is black. I would like to configure the compression such it will take into account the surrounding frames and that after a compress and decompress I will notice an effect of the surrounding over the black frame. Is there any way to configure the compression at the command line for doing that ?

Thanks, Dor D. Ma'ayan

[Dor Ma'ayan]

Currently I use the following configuration and it does not seems to work well: x265.exe --profile main --input %s --input-res %dx%d --fps %d --frames %d --output %s --crf %d --no-info --rd 6

[Pradeep Ramachandran]

This is a portal to report issues (bugs/feature requests, etc.) with x265. If you want help with ways to use x265, I encourage you to write to our mailing list ([e-mail]), or post on our forum on doom9 (https://forum.doom9.org/showthread.php?t=168814&page=271)

[Tom Vaughan]

You’re saying that every other frame is black? In other words, your video alternates between actual video frames and black frames? That doesn’t fit the normal definition of video, and it’s not what a video codec expects. This will confound x265’s scene detection (x265 may think that every frame is a new scene). x265 might be able to compress it fairly efficiently if you use a setting that allows for a fixed keyframe interval which always starts on a frame with actual video (not a black frame). I would use a setting with at least 3 B frames.

It would be much better to get rid of the black frames, and then just encode at half the frame rate. Feeding these alternating black frames into the encoder isn’t the right design.

[Dor Ma'ayan]

I know that feeding the black frames does not seems right, but thats all the idea behind my research is trying to restore the black frames using the compression. I would like to see the influence of surrounding frames over the black frames while iteratively compress-decompress the video with different compression ratios