simonkmr / openh264lib.net

Cisco's openh264 wrapper library for .NET Framework.

OpenH264Lib.NET

Cisco's openh264 wrapper library for .NET Framework.
Written in C++/CLI to bridge other .NET Framework language like C#.  

How to use

// create encoder and decoder
var encoder = new OpenH264Lib.Encoder("openh264-2.1.1-win32.dll");
var decoder = new OpenH264Lib.Decoder("openh264-2.1.1-win32.dll");

// setup encoder
float fps = 10.0f;
int bps = 5000 * 1000;         // target bitrate. 5Mbps.
float keyFrameInterval = 2.0f; // insert key frame interval. unit is second.
encoder.Setup(640, 480, bps, fps, keyFrameInterval, (data, length, frameType) =>
{
    // called when each frame encoded.
    Console.WriteLine("Encord {0} bytes, frameType:{1}", length, frameType);
    
    // decode it to Bitmap again...
    var bmp = decoder.Decode(data, length);
    if (bmp != null) Console.WriteLine(bmp.Size);
});

// encode frame
foreach(var bmp in bitmaps)
{
    encoder.Encode(bmp);
}

See Example

1. Open 'OpenH264Lib.sln' Visual Studio solution file.
2. Build OpenH264Lib project from VisualStudio 'Build OpenH264Lib' menu. (Not 'Build Solution'), or in Solution Explorer, right click 'OpenH264Lib' project and build. Then created OpenH264Lib.dll.
3. Build OpenH264Sample project from VisualStudio 'Build Solution' menu, or in Solution Explorer, right click 'OpenH264Sample' project and build. This is example C# project how to use OpenH264Lib.dll.
4. Download 'openh264-2.1.1-win32.dll' from Cisco's openh264 Github repository, and copy it to OpenH264Sample/bin/Debug/ directory.
   • If you are going to use 'openh264-x.x.x-win64.dll', build dll and exe as x64 pratform in step (2) and (3).
   • Use Cisco's dll version 2.1.0 and later. (issue #19). If you are going to use dll version 2.0.0 and before, use old repository.
5. Execute OpenH264Sample.exe. This program encode image files to H264 avi file, and decode avi to image.

Remarks

Since this is only a wrapper library, you have to know about original openh264 implementation when you add/modify features.

And...

You can make H264 video recorder by using OpenH264Lib.NET and UsbCamera and AviWriter(in MotionJPEGWriter).

int index = 0;
var camera = new Github.secile.Video.UsbCamera(index, new Size(640, 480));
camera.Start();

// create H264 encorder.
var path = System.Environment.GetFolderPath(Environment.SpecialFolder.DesktopDirectory) + @"\test.avi";
var encoder = new OpenH264Lib.Encoder("openh264-2.1.1-win32.dll");

// write avi for every frame encorded.
var fps = 10.0f;
var writer = new Github.secile.Avi.AviWriter(System.IO.File.OpenWrite(path), "H264", camera.Size.Width, camera.Size.Height, fps);
OpenH264Lib.Encoder.OnEncodeCallback onEncode = (data, length, frameType) =>
{
    var keyFrame = (frameType == OpenH264Lib.Encoder.FrameType.IDR) || (frameType == OpenH264Lib.Encoder.FrameType.I);
    writer.AddImage(data, keyFrame);
    Console.WriteLine("Encord {0} bytes, KeyFrame:{1}", length, keyFrame);
};

// setup encorder.
int bps = 100000; // 100kbps
encoder.Setup(camera.Size.Width, camera.Size.Height, bps, fps, 2.0f, onEncode);

// encode image for every captured image.
var timer = new System.Timers.Timer(1000 / fps) { SynchronizingObject = this };
timer.Elapsed += (s, ev) =>
{
    var bmp = camera.GetBitmap();
    pbxImage.Image = bmp;
    encoder.Encode(bmp);
};
timer.Start();

// release resource when close.
this.FormClosing += (s, ev) =>
{
    camera.Release();
    timer.Stop();
    writer.Close();
    encoder.Dispose();
};