docs/index.md
Please read the documentation before creating an issue. Thank you π
.llc files that get created?
See also π Recipe cookbook.
If you have a problem with the app or with a file, please see the π€ Troubleshooting, known issues and limitations.
Export mode from Separate files to Merge cuts.Working dir unset button (defaults to same folder as source file).Tracks button to customise and/or add new tracks from other files.Export button (or <kbd>E</kbd>) to show an overview with export options.Export again to confirm the exportHere's a little primer about video and audio formats for those not familiar. A common mistake when dealing with audio and video files, is to confuse formats, codecs, and file names. In short: A file's media format is a container that holds one or more codecs (audio/video/subtitle) inside of it. For example .mov is a container format, and H265/HEVC is a codec. Some formats support only a few kinds of codecs inside of them (e.g. .wav), while others support almost all codecs (e.g. Matroska). The most common formats are MP4/MOV (often .mp4,.mov,.m4a) and Matroska (often .mkv,.mka). Example: If you have a file named My video.mp4, this file most likely (but not necessarily) has the format MP4. Note that the extension of a file (in this case .mp4) doesn't really mean anything, and the file could in reality for example have the MOV format, or the extension could be .txt. Inside My video.mp4 there are multiple tracks/streams, each with their own codec. In this example, let's say that it contains one H264 track and one AAC track. In LosslessCut you can view and add/delete/modify these tracks.
Remuxing: If you change the output format in LosslessCut and export a file, you are remuxing the tracks/codecs into a different container format. When you do this, the operation is in theory lossless, meaning you will not lose any codec data and the different tracks will remain exactly the same, even though the format is now different (but some format metadata might get lost due to incompatibilities between container formats). There are limitations: Some popular codecs like VP8 or VP9 are not supported in popular formats like MP4, and some popular formats like Matroska (.mkv) are not natively supported in popular video players like iPhone or QuickTime.
If you want to reduce the size of a file using LosslessCut you have to "get rid of" something, either:
Here is a great introduction to audio/video: howvideo.works.
Segments are the first class citizens of LosslessCut. A segment is a time-slice of your source media file, defined by a start time and an end time. When a segment has no end time, it's called a marker. Segments have a segment number (their export order), and can optionally have a label and tags. Segments are be the basis of what gets exported.
A segment that has no end time is called a marker. It has no length and will be excluded from exports, but behaves similar to segments. Markers are distinctively visualized on the timeline with a vertical line and a number on top. You can convert markers to segments by setting their out-point (<kbd>O</kbd>). This can be done manually or automated with one of the many tools in LosslessCut. For example you can invert all segments on the timeline to convert all markers into segments.
Tracks are different from segments, in that the tracks run in parallel. For example most videos have one video track and one audio track. When cutting, LosslessCut will cut all tracks equally, although there are some tracks that cannot be cut. The LosslessCut tracks panel is used to selectively enable/disable individual tracks for export and edit track or file metadata. It can also be used to change content disposition.
LosslessCut default project file .llc is in a JSON5 format. It contains information about the segments in your timeline. LosslessCut also allows importing/exporting your project (segments) in a variety of file formats. See list of supported formats.
segment start, segment end, label.segment start and segment end are expressed in seconds. segment end may be empty, in that case it's a marker., to separate the fields (not semicolon ;).csv file,56.9568,First segment starting at 0
70,842.33,"Another quoted label"
1234,,Last marker starting at 1234 seconds
Same as CSV but <tab> instead.