Deblocking video

How do you deblock (remove or reduce the blocking effect from compressed video) in Kdenlive?

What do you mean by «compressed video”?

Click on the clip in the timeline, the effect stack window should open, and you can delete the effect (red bin icon).

If the effect is not on the clip in the timeline, then you have it applied direct to the whole clip. Click on the project bin tab, click on the clip, and check in the effect stack window if the effect is applied. If yes delete the effect.

That is not what I mean, have you ever viewed a video on YouTube that is compressed so much that it has block or square shaped artifacts, that is what I mean, how do I get rid of the those square blocky shaped artifacts (pixelation) from an over compressed video in order to clean it up and make it clearer. So how do I depixelate a pixelated video in Kdenlive? Below is an example of a blocky and pixelated frame from compressed video. I know this can be done with Virtualdub2 http://virtualdub2.com/ with an addon filter called MSU Smart Deblocking https://compression.ru/video/deblocking/smartdeblocking_en.html, but I was wondering if it could be done with Kdenlive.

preproc_src

De-blurring/de-blocking is not possible in Kdenlive. Virtual Dub is the way to go. I think there are any AI program as well.

Yes I agree, I think Virtualdub2 is a good tool to use, I have also found another free tool used in police forensics for cleaning up video footage and images, it is called Video Cleaner https://videocleaner.com/ it is apparently the industry standard for video and photo forensics. I think it could be very useful for the average person for enhancing, cleaning up and and sharpening blurry or pixelated videos and photos. It is built with AviSynth http://avisynth.nl/index.php/Main_Page, Video Cleaner also comes with specialized tools for detecting if a video has been manipulated, this could be very useful for scrutinizing YouTube videos in order find out if the video is faked or not, although AI faked videos would probably be more difficult to detect, and you would have to download the YouTube, Dailymotion, Vimeo, etc… video that you want to analyse and scrutinize. For anyone who wants to upscale videos or images, there is a free open source tool called Video2x https://github.com/k4yt3x/video2x

You can actually deblur a video in Kdenlive using the Sharp/Unsharp filter as well as the deprecated Sharpen filter and there is also another filter called Contrast Adaptive Sharpen. So yes you can sharpen blurry video in Kdenlive. However to do more complex sharpening and deblocking (depixelization), you would need Virtualdub2 or Video Cleaner. Perhaps those are features that could be added to Kdenlive, a more indepth sharpening filter and a deblocking (depixelization) filter. To me those are the two most common problems people encounter with videos found on the internet, blurry videos and blocky (pixelized) videos, especially older videos, such as 360p and 480p videos. Another feature that could be added to Kdenlive would be the ability to upscale video like Video2x can do. There are probably instances where people will have to make use of old SD (low def) 360p and 480p videos as well as 720p videos, so to have all the necessary tools needed to enhance these old videos built right into Kdenlive would be very handy and very convenient. It is nice however to know that there are existing free software tools for doing these particular things. These 3rd party tools can be used in addition to Kdenlive.