# MP4 output

Media Blocks SDK .Net

MP4 is the most popular video format available for all platforms. Typically, AAC is used to encode the audio stream, and H264 or HEVC codecs are used to encode the video stream.

Use the MP4SinkSettings class to set the parameters.

# Block info

Name: MP4SinkBlock.

Pin direction	Media type	Pins count
Input audio	audio/mpeg	one or more
	audio/x-ac3
	audio/x-alac
	audio/x-opus
Input video	video/mpeg	one or more
	video/x-divx
	video/x-h264
	video/x-h265
	video/x-av1
Input subtitle	text/utf8	one or more

# The sample pipeline

graph LR;
    UniversalSourceBlock-->H264EncoderBlock;
    UniversalSourceBlock-->AACEncoderBlock;
    H264EncoderBlock-->MP4SinkBlock;
    AACEncoderBlock-->MP4SinkBlock;

# Sample code

var pipeline = new MediaBlocksPipeline();

var filename = "test.mp4";
var fileSource = new UniversalSourceBlock(await UniversalSourceSettings.CreateAsync(new Uri(filename)));

var aacEncoderBlock = new AACEncoderBlock();
pipeline.Connect(fileSource.AudioOutput, aacEncoderBlock.Input);

var h264EncoderBlock = new H264EncoderBlock();
pipeline.Connect(fileSource.VideoOutput, h264EncoderBlock.Input);

var mp4SinkBlock = new MP4SinkBlock(new MP4SinkSettings("output.mp4"));
pipeline.Connect(h264EncoderBlock.Output, mp4SinkBlock.CreateNewInput(MediaBlockPadMediaType.Video));
pipeline.Connect(aacEncoderBlock.Output, mp4SinkBlock.CreateNewInput(MediaBlockPadMediaType.Audio));

await pipeline.StartAsync();

To create fragmented MP4 file (with split by size or duration), use the MP4SplitSinkSettings class.

# Sample applications

# Platforms

Windows, macOS, Linux, iOS, Android.