public string VideoCompress(string videoPath)
{
mOutputResolution = Resolution.RESOLUTION_480P;
mOutputBitRate = 1048576;
mOutputFrameRate = 30;
mOutputIFrameInterval = 10;
this.mInputUri = Android.Net.Uri.Parse(videoPath);
mOutputUri = GetOutputUri(this.mInputUri.Path);
VideoResampler resampler = new VideoResampler();
resampler.AddSamplerClip(new SamplerClip(mInputUri));
resampler.SetOutput(mOutputUri);
resampler.SetOutputResolution(mOutputResolution.mWidth, mOutputResolution.mHeight);
resampler.SetOutputBitRate(mOutputBitRate);
resampler.SetOutputFrameRate(mOutputFrameRate);
resampler.SetOutputIFrameInterval(mOutputIFrameInterval);
try
{
this.IsBusy = true;
resampler.Start(this);
}
catch (Exception e)
{
}
return(mOutputUri.ToString());
}
public unsafe void Scale()
{
var sourceFormat = new VideoFormatInfo(PixelFormat.Bgra32, 1000, 1000);
var targetFormat = new VideoFormatInfo(PixelFormat.Rgb24, 100, 100);
using (var source = new VideoFrame(sourceFormat))
using (var target = new VideoFrame(targetFormat))
using (var resampler = new VideoResampler(sourceFormat, targetFormat, SwsFlags.Lanczos))
{
Assert.Equal(300, target.Strides[0]);
var pixels = MemoryMarshal.Cast <byte, Bgra32>(source.Memory.Span);
pixels.Fill(new Bgra32(new Rgba32(1, 2, 3, 4)));
Assert.Equal(1000 * 1000 * 4, source.Memory.Length);
Assert.Equal(100 * 100 * 3, target.Memory.Length);
resampler.Resample(source, target);
int i = 0;
foreach (Rgb24 pixel in MemoryMarshal.Cast <byte, Rgb24>(target.Memory.Span))
{
if (!pixel.Equals(new Rgb24(1, 2, 3)))
{
throw new Exception($"{i} | {pixel.R},{pixel.B},{pixel.G})");
}
Assert.Equal(new Rgb24(1, 2, 3), pixel);
i++;
}
}
}
public unsafe void ChangePixelFormat()
{
var sourceFormat = new VideoFormatInfo(PixelFormat.Bgra32, 100, 100);
var targetFormat = new VideoFormatInfo(PixelFormat.Rgb24, 100, 100);
using (var source = new VideoFrame(sourceFormat))
using (var target = new VideoFrame(targetFormat))
using (var resampler = new VideoResampler(sourceFormat, targetFormat))
{
Assert.Equal(300, target.Strides[0]);
var pixels = MemoryMarshal.Cast <byte, Bgra32>(source.Memory.Span);
pixels.Fill(new Bgra32(new Rgba32(1, 2, 3, 4)));
Assert.Equal(100 * 100 * 4, source.Memory.Length);
Assert.Equal(100 * 100 * 3, target.Memory.Length);
resampler.Resample(source, target);
foreach (Rgb24 pixel in MemoryMarshal.Cast <byte, Rgb24>(target.Memory.Span))
{
Assert.Equal(new Rgb24(1, 2, 3), pixel);
}
}
}
static void Main(string[] args)
{
Bitmap bitmap = new Bitmap(@"Z:\1.png");
VideoFrame inFrame = new VideoFrame(new VideoFormat(bitmap.Width, bitmap.Height, AVPixelFormat.Bgr24, 4));
VideoFrame outFrame = new VideoFrame(new VideoFormat(1366, 768, AVPixelFormat.Yuv420p, 16));
var bitmapData = bitmap.LockBits(new Rectangle(Point.Empty, bitmap.Size), System.Drawing.Imaging.ImageLockMode.ReadOnly, System.Drawing.Imaging.PixelFormat.Format24bppRgb);
inFrame.Update(bitmapData.Scan0);
bitmap.UnlockBits(bitmapData);
var resampler = new VideoResampler(inFrame.Format, outFrame.Format, SwsFlags.Bicublin);
resampler.Resample(inFrame, outFrame);
using (var file = File.OpenWrite(@"Z:\1.yuv")) {
Write(file, outFrame.Data[0], outFrame.Format.Strides[0] * outFrame.Format.Height);
Write(file, outFrame.Data[2], outFrame.Format.Strides[2] * outFrame.Format.Height / 2); //V
Write(file, outFrame.Data[1], outFrame.Format.Strides[1] * outFrame.Format.Height / 2); //U
}
}
