Container format
Also known as: container, wrapper, file format
The file wrapper, such as MP4, MOV or MKV, that holds video, audio and metadata streams together. It is separate from the codec that compresses them.
Updated
What it means
A video file has two layers. The codec, such as H.264 or HEVC, compresses the actual pictures and sound. The container wraps those compressed streams together with timing information, chapter markers, subtitles and metadata, and gives the file its extension.
Common containers include MP4, MOV, MKV, AVI and WebM. The same H.264 video can sit inside an MP4 or a MOV, and a player needs to understand both the container and the codec to play the file.
That is why two files with the same extension can behave differently: the container matches, but the codec inside does not.
How it works in practice
Action cameras mostly use MP4, while iPhones and many pro cameras use MOV. Editing software usually handles both. MKV is popular for screen recordings and downloads because it is flexible and recovers well from interrupted recordings.
Changing only the container, called remuxing, is fast and lossless, because the compressed streams are copied as they are. Changing the codec, called transcoding, re-encodes the video and takes longer.
When a file will not open, checking the codec inside with a media info tool is the fastest way to find out why. Often the container is fine and the codec is simply one your software cannot decode.
What to watch out for
Renaming a file extension does not change its container. Turning video.mkv into video.mp4 by renaming can make some apps refuse it or misread it. Use a proper remux tool instead.
Containers also carry important side data such as rotation flags, color tags and camera telemetry. Some conversions drop these, which can leave clips sideways, with wrong colors or without the gyro data that tools like Gyroflow need for stabilization.
Keep the originals untouched and convert copies when a different container is needed. If something goes wrong in a conversion, you can always go back and try another tool, and nothing from the shoot is lost.
How RawClip handles it
RawClip accepts MP4 and MOV uploads, and AVI and MKV are accepted too. For the most reliable results, upload the original camera MP4 or MOV files, and the AI builds your highlight from them.