/// <summary>
/// create a 60 / <paramref name="fps"/> second video
/// </summary>
/// <param name="outputFile">video output</param>
/// <param name="width">video width</param>
/// <param name="height">video height</param>
/// <param name="fps">video fps</param>
public EncodeVideoByMat(string outputFile, int width, int height, int fps)
{
using (MediaWriter writer = new MediaWriter(outputFile))
{
writer.AddStream(MediaEncoder.CreateVideoEncode(writer.Format, width, height, fps));
writer.Initialize();
VideoFrame dstframe = VideoFrame.CreateFrameByCodec(writer[0].Codec);
Random random = new Random();
for (int i = 0; i < 61; i++)
{
// create a video frame by Mat
byte b = (byte)random.Next(0, 255);
byte g = (byte)random.Next(0, 255);
byte r = (byte)random.Next(0, 255);
using (Image <Bgr, byte> image = new Image <Bgr, byte>(width, height, new Bgr(b, g, r)))
{
string line1 = $"pts = {i}, color = [{b,3},{g,3},{r,3}]";
string line2 = $"time = {DateTime.Now:HH:mm:ss.fff}";
image.Draw(line1, new System.Drawing.Point(30, 50), Emgu.CV.CvEnum.FontFace.HersheyDuplex, 1, new Bgr(255 - b, 255 - g, 255 - r));
image.Draw(line2, new System.Drawing.Point(30, 100), Emgu.CV.CvEnum.FontFace.HersheyDuplex, 1, new Bgr(255 - b, 255 - g, 255 - r));
dstframe = image.Mat.ToVideoFrame(AVPixelFormat.AV_PIX_FMT_YUV420P);
}
dstframe.Pts = i; // video pts = seconds from video start * fps (pts can only increase).
// write video frame, many cases: one frame more out packet, first frame no out packet, etc.
// so use IEnumerable.
foreach (var packet in writer[0].WriteFrame(dstframe))
{
writer.WritePacket(packet);
}
}
// flush cache
writer.FlushMuxer();
}
}