LoselessCut
LosslessCut is FFmpeg's cross-platform GUI for fast lossless trimming of video, audio, subtitles and other media files.
Its main function is lossless trimming and slicing of video and audio files, which is very convenient for saving space by rough trimming large video files
It allows you to quickly extract good fragments from video and get rid of many gigabytes of data without resorting to slow re-encoding and consequent loss of quality.
loselesscut