Trim a video on your phone without losing quality

Overview

Open a video, and a filmstrip appears with a handle at each end. Drag them until the part you want sits between them, check it in the preview and tap Save. iEdit then copies that section into a new file without decoding or re-encoding a single frame. The picture, the sound and the codec are exactly what the camera recorded, so there is no generation loss, and the original stays untouched in your library.

Because the stream is copied rather than re-encoded, a cut can only begin on a keyframe. If you place the start between two keyframes, iEdit moves it back to the previous one and tells you so; the end is cut where you set it. On iOS the copy is done with AVFoundation passthrough, on Android with MediaExtractor and MediaMuxer, so the behaviour is the same on both. Long clips are handled in the background and a notification tells you when the file is ready.

Trimming is the first step for most short videos: the seconds before someone starts talking, the shaky ending of a clip, the one good take in a long recording. Since the cut is lossless there is no reason to hesitate over it, and the trimmed file is as good a master as the original. Everything happens on the device, so it works on a train or a plane as well as at home.