SharpMP4

Simple lightweight fragmented mp4 (fmp4) reader/writer. Supports H264/H265/H266/AV1 for video and AAC/Opus for audio. No platform dependencies, easily portable cross-platform. It was designed to be a stream-in and stream-out solution for recording streams from IP cameras into fragmented MP4.

Read MP4

To parse an existing mp4/mov/m4v file, first you have to get the stream:

using (Stream inputFileStream = new BufferedStream(new FileStream("frag_bunny.mp4", FileMode.Open, FileAccess.Read, FileShare.Read))) { ... }

Create a new Container and call Read to get the in-memory representation of all the boxes.

var mp4 = new Container(); mp4.Read(new IsoStream(inputFileStream)); ...

To process this in-memory representation and read the audio/video samples, create a new VideoReader:

VideoReader videoReader = new VideoReader(); videoReader.Parse(fmp4);

Now it is possible to get all the tracks from the video:

IEnumerable<ITrack> tracks = videoReader.GetTracks();

To read the first track samples, call:

uint trackID = tracks.First().TrackID; MediaSample sample = videoReader.ReadSample(trackID);

Where trackID is the ID of the track you want to read.

Build MP4

To write MP4 into a file, you first have to create the file:

using (Stream output = new BufferedStream(new FileStream("bunny_out.mp4", FileMode.Create, FileAccess.Write, FileShare.Read))) { ... }

Next, create the builder depending upon the output format. Currently, there are two builders - FragmentedMp4Builder and Mp4Builder.

IMp4Builder outputBuilder = new Mp4Builder(new SingleStreamOutput(output));

Add the H264 video track to the builder instance:

var videoTrack = new H264Track(); outputBuilder.AddTrack(videoTrack);