nwjs-ffmpeg-prebuilt VS lossless-cut

You need libffmpeg. You can download a prebuilt one from here. Put libffmpeg.so file to lib_extra directory at Opera's installation directory (probably /usr/lib64/opera).

How to Install libffmpeg (for proprietary h.264 and aac support) for Opera for Linux_x64 Goto the URL opera://about and look at the "Browser identification" (User-Agent) string to see what major version of Chromium Opera is using (79, 80, 81, 82 etc.). Also, take note of the "install" path. You'll need that later. Goto https://github.com/iteufel/nwjs-ffmpeg-prebuilt/releases/ and download the latest -linux-x64.zip that's built with the same major version of Chromium that your Opera is. For example, if your Opera is built with Chromium 79, goto https://github.com/iteufel/nwjs-ffmpeg-prebuilt/releases/tag/0.43.6 and download 0.43.6-linux-x64.zip. Or, goto https://packages.ubuntu.com/search?keywords=chromium-codecs-ffmpeg-extra and click on the link to the distro that has "chromium-codecs-ffmpeg-extra" for the version of Chromium you need. Then, on the page for the distro, click the "amd64" link to goto the download page. On the download page, you can download the deb file and then extract it to get libffmpeg.so out of it. For example, if you need libffmpeg.so for Chromium 81, goto https://packages.ubuntu.com/focal-updates/amd64/chromium-codecs-ffmpeg-extra/download and download the the deb file. (in this case though, ignore that and use the libffmpeg.so in http://security.ubuntu.com/ubuntu/pool/universe/c/chromium-browser/chromium-codecs-ffmpeg-extra\_83.0.4103.61-0ubuntu0.18.04.1\_amd64.deb that's from https://packages.ubuntu.com/bionic/chromium-ffmpeg-extra even though it says it's for Chromium 83) If nothing works, try a libffmpeg.so for the next version of Chromium and so on. Once you have the zip/deb file, extract it to get libffmpeg.so. Then, create the folder lib_extra in Opera's install folder that you took note of in opera://about earlier and put libffmpeg.so in the lib_extra folder. The path to libffmpeg.so should then be opera_install_folder/lib_extra/libffmpeg.so. On Linux Mint, that'd be /usr/lib/x86_64-linux-gnu/opera/lib_extra/libffmpeg.so. On Arch Linux, it might be /usr/lib64/opera/lib_extra/libffmpeg.so. Again, goto the URL opera://about in Opera and look at the "install" path.

For lossless cut, there's the LosslessCut [1] app, which even has an experimental but mostly working version of a "smart cut" feature [2] (aka. only re-encode the minimal mandatory amount of frames if you trim at a point between 2 key frames)

[1]: https://github.com/mifi/lossless-cut

[2]: https://github.com/mifi/lossless-cut/issues/126

> thought I cropped/edited a video, it is still there in full length and resolution

It's been possible to create a clip from a video file that merely changes what parts of the video are displayed without effecting the data in the original since the Classic Mac OS days.

If you want to completely remove unwanted portions of a video to reduce the size without a loss of quality, there are many options. LosslessCut is one option that is both free and open source.

https://github.com/mifi/lossless-cut

LosslessCut

Lossless Cut is probably the simplest way to cut out parts of a video without having to re-encode it or use an online service. It is open source, free and available for all platforms. It is in essence a frontend for FFMPEG and cuts without re-encoding, so the results are instantaneous.

Additionally I would like if possible to shorten (both to reduce dimension and to make them less boring) my videos by trimming the beginning and/or ends where often there is nothing interesting happening and possibly change the thumbnails for easier identification. Do you know of any tool that does the job with the minimum quality degradation possible? Many years ago I've tried with some videos and a tool I don't remember anymore, ending up with a bunch of corrupted files :( I've found https://github.com/mifi/lossless-cut for the point above.. need to try it. please let me know what experience you have with it.

Lossless Cut would probably be a better choice for this. Will let you cut out the commercials without having to re-encode the video.

>Of course, you could only re-encode only the GoPs that get broken while keeping the rest intact, and I guess this would be better and a lot faster than re-encoding everything. I don't know if any application tries to do this.

LosslessCut does have experimental support for this partial re-encode called "smart cut" [1]. Since it's using ffmpeg internally, the challenge become how to instruct ffmpeg to do this[2]?

[1]: https://github.com/mifi/lossless-cut/issues/126