Lets say i’ve a video from a live stream where the face looks a little mosaic.
Is there an anti-mosaic filter?
Should i use the sharpen filter?
Thank you
No, there is no filter for this.
It’s almost impossible to get back something to it original form if it is mosaic now, that needs some really heavy AI. Maybe a grainy face could be solved in the future, but I don’t think a mosaic face would be available that soon. I think that it could available in the next 4 years.
I mean grains can be joined and solved because they are very small, but mosaic are bigger boxes.
Shotcut has a filter that attempts to reverse (or at least smoothen) the blocking artefacts caused by extreme compression. It’s called “Reduce Noise: Quantization” in the filter list, but is actually an implementation of the FFmpeg fspp filter. More detail about how fspp works can be found at the FFmpeg PostProcessing wiki:
https://trac.ffmpeg.org/wiki/Postprocessing
Of note with block artefacts… the Sharpen filter usually accentuates the block borders rather than increase the detail of the block interiors. The result usually draws more attention to the blocks rather than less.
Also, fine-detail noise reduction algorithms like “Reduce Noise: Wavelet” do not work well on blocky material. The blocks are pronounced enough that the filter regards the boundaries as intentional detail, and thus preserves the block borders rather than eliminate them. A better algorithm on blocky video is “Reduce Noise: HQDN3D”, optionally applied after the fspp filter.
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Clever, why didn’t I use the quantization filter on my last 20 videos. I should have at least tried it.
Thank you!
To be fair to you, I doubt most people would recognize what that filter is doing by its name. While it is technically correct about fixing quantization, it’s not an intuitive term to a casual user. Perhaps “Reduce Noise: Blockiness” would be more intuitive, or “Deblock: Fast Simple” which would allow the other deblock filters to be added in the future. Each deblock filter in FFmpeg specializes at handling different kinds of artefacts with different degrees of success.
However, the far more interesting question is why your new high-spec computer is editing 20 low-quality videos. 
Uh, those 2007 vids from my grandpa, I wonder why he doesn’t buy a dslr from those 600$, I mean the Nikon D40 was at a good price at that time, I remember someone in Delhi (where I lived at that time) imported that camera, and it was pretty nice stuff. Gpa just bought a camcorder (360p) and somehow liked it better than any dslr at that time.
Fair enough lol. Editing ancient family footage is a noble cause. I was worried that if low-quality footage was all you were doing, then your over-spec’ed computer might be like swatting a mosquito with a bulldozer.
That would never happen, I have lot of HD and raw videos left to edit. That would take more than a month or so.
Damn… now you tell us. Reading that paragraph made me feel bad about myself. So I threw all my pink bath towels to the trash…
The recording of those are not true.
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