FOSSPicks

Video editor

LosslessCut

Regardless of the incredible performance advances we've made over the past two decades, video editing can feel almost as slow as editing with Media 100 on PowerPC Macintosh in 1995 and writing to a tape drive. This is for a few reasons, but it's mostly because our demands scale to fit our capabilities. Video resolution, color depth, and frame rates have scaled to accommodate all that spare processing, and files nearly always need to be transcoded from one format to another before they can be used. This latter roadblock is something that LosslessCut attempts to mitigate. Powered by the incredibly versatile FFmpeg, LosslessCut can edit huge videos and, vitally, can export them quickly with no loss of quality. It accomplishes this by only letting you edit at specific keyframes in a video stream, avoiding the processor-intensive need to recalculate frames that may fall between keyframes. By sticking to keyframe edits, the video data can simply be rewritten without the edited out parts.

With most of us now recording 4K video on our phones or GoPro equivalents, quick editing like this is the perfect solution. We're not looking for the perfect edit, but instead a way of cutting quickly to the action, chopping the preamble or appendices from the beginning and ends of our videos. With LosslessCut, you can simply drag-and-drop a video into the main application window, locate the "edit-in" point, locate the "edit-out" point, and save the middle segment as a new, shorter video. This does mean you can't perform any other kind of editing task, such as crop, rotate, reflect, or filter processing, because these tasks would require frame and keyframe recalculation, and therefore, a lossy-intensive transformation. The only other disadvantage is that you can't always edit at the exact point you want to since the edit or split point will move to the closest keyframe. Fortunately, there are key icons in the UI that will automatically move the cursor to keyframes and perfect edit points. With those limitations accounted for, the performance bottleneck becomes storage access rather than the transcoding that other applications need to perform.

Editing between keyframes is being worked on, with a recent development release capable of reconstructing the frames after or before a keyframe enabling editing anywhere with only some processing and lossy overhead for the reconstructed part. The remainder of the video will be unaffected, which is still a big improvement on how most video editors work. The rest of the UI is simple but effective. An advanced view enables you to turn on waveform and thumbnail timelines, set the zoom level, take a single image, and see the resolution and frame rate details for your clip. You can also import multiple files, although they currently have to be edited separately rather than on different tracks as you might in Kdenlive – although that feature too is coming. When you've finished, you can export your edits as either a merged single segment or as multiple files, and while the emphasis is obviously to keep the original encoding, you can also choose to convert the output segment to any format supported by FFmpeg. This makes LosslessCut a great front end to file conversion, in addition to meeting all your instant editing needs.

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