我正在尝试编写一个用于将Windows桌面录制到视频文件的应用程序。我正在使用桌面复制API和Media Foundation API。更具体地说，我正在使用Media Foundation的SinkWriter类。我正在使用Desktop Duplication API中的Texture2D个对象，并将它们传递给SinkWriter，这形成了一个很好的硬件加速管道。我还将C＃与SharpDX一起使用。
整个项目在大多数情况下都运行良好。它可以在我的Surface Pro上完美运行，可以捕获相当一致的fps视频，而不会出现问题。
问题出在其他硬件上。具体来说，我已经测试了我在带有独立Nvidia GPU的AMD Ryzen上进行的测试。这也很好用..除了通常在8到20秒之间记录桌面之后，该程序将被锁定在outputDuplication.ReleaseFrame()或outputDuplication.AcquireNextFrame()上。它不会崩溃，它只会锁定，因此我不确定如何确定发生了什么。我确实知道，这与将桌面纹理传递到sinkWriter.WriteSample()函数有关。如果我删除了这一行，并保持其他所有内容不变，则像往常一样继续创建MediaBuffers和MediaSamples，将它们与我的桌面纹理相关联，但不要将示例传递给WriteSample方法，那么应用程序可以愉快地无限期地“记录”。
我已经检查了所有我能想到的潜在错误。我确保应将所有对象都丢弃。我看不到任何内存泄漏。该代码在SetAllocator()上使用MediaSample方法，因此我传递给SinkWriter的纹理被回收了。据我所知，这一切都正常。
我怀疑这里有一些我不了解的基本知识。正确管理SharpDX后面的非托管资源似乎犯了一些错误，但是我真的不知道从哪里开始。此时，任何指针都将不胜感激。
这是主要的捕获代码。这不是全部，而是大部分。我怀疑问题出在这里。
static void WriteFrame(SinkWriter sinkWriter, int steamIndex, long time, long duration, int width, int height, Texture2D texture, TextureAllocator textureAllocator)
{
MediaBuffer textureBuffer;
MediaFactory.CreateDXGISurfaceBuffer(texture.GetType().GUID, texture, 0, false, out textureBuffer);
using (var buffer2d = textureBuffer.QueryInterface<Buffer2D>())
{
textureBuffer.CurrentLength = buffer2d.ContiguousLength;
}
using (var sample = MediaFactory.CreateVideoSampleFromSurface(null))
{
sample.SampleTime = time;
sample.SampleDuration = duration;
sample.AddBuffer(textureBuffer);
using(var trackedSample = sample.QueryInterface<TrackedSample>())
{
trackedSample.SetAllocator(textureAllocator, null);
}
sinkWriter.WriteSample(steamIndex, sample);
}
textureBuffer.Dispose();
}
void captureAction()
{
MediaManager.Startup(true);
int streamIndex = 0;
var whichOutputDevice = 0;
var whichAdapter = 0;
using (var factory = new Factory1())
{
using (var adapter = factory.GetAdapter1(whichAdapter))
{
using (var mDevice = new SharpDX.Direct3D11.Device(adapter))
{
using (var dXGIDeviceManager = new DXGIDeviceManager())
{
dXGIDeviceManager.ResetDevice(mDevice);
using (var output = adapter.GetOutput(whichOutputDevice))
{
using (var output1 = output.QueryInterface<Output1>())
{
var mOutputDesc = output.Description;
var mTextureDesc = new Texture2DDescription()
{
CpuAccessFlags = CpuAccessFlags.Read,
BindFlags = BindFlags.None,
Format = Format.B8G8R8A8_UNorm,
Width = mOutputDesc.DesktopBounds.Right - mOutputDesc.DesktopBounds.Left,
Height = mOutputDesc.DesktopBounds.Bottom - mOutputDesc.DesktopBounds.Top,
OptionFlags = ResourceOptionFlags.None,
MipLevels = 1,
ArraySize = 1,
SampleDescription = { Count = 1, Quality = 0 },
Usage = ResourceUsage.Staging
};
using (var outputDuplication = output1.DuplicateOutput(mDevice))
{
using (var sinkWriter = InitialiseSinkWriter(path, out streamIndex, mTextureDesc.Width, mTextureDesc.Height, frameRate, mDevice, dXGIDeviceManager, preferHardwareAcceleration))
{
using (var rgbToNv12 = new RGBToNV12ConverterD3D11(mDevice, mDevice.ImmediateContext, mTextureDesc.Width, mTextureDesc.Height))
{
var newDesc = mTextureDesc;
if (forceNV12)
newDesc.Format = Format.NV12;
newDesc.BindFlags = BindFlags.RenderTarget;
newDesc.Usage = ResourceUsage.Default;
newDesc.CpuAccessFlags = CpuAccessFlags.None;
var textureAllocator = new TextureAllocator(mDevice, newDesc);
{
var timeStart = 0L;
var frameCount = 0;
var totalAFMilliseconds = 0.0;
var lastTimeStamp = 0L;
var frameAquired = false;
for (int i = 0; !stopCapture; i++)
{
var sleepAmount = Math.Max(0, (1000 / frameRate) / 2);
System.Threading.Thread.Sleep(sleepAmount);
frameCount++;
SharpDX.DXGI.Resource desktopResource = null;
var frameInfo_ = new OutputDuplicateFrameInformation();
var sw = new Stopwatch();
sw.Start();
var outputLoopCount = 0;
if (outputDuplication != null)
{//desktop duplication
int aquireFrameLoopCount = 0;
while (frameInfo_.LastPresentTime == 0)
{
aquireFrameLoopCount++;
if (aquireFrameLoopCount > 1)
{
System.Threading.Thread.Sleep(1);
}
if (frameAquired)
try
{
outputDuplication.ReleaseFrame();
frameAquired = false;
}
catch (Exception e)
{
}
try
{
outputDuplication.AcquireNextFrame(500, out frameInfo_, out desktopResource);
frameAquired = true;
}
catch (Exception e)
{
}
outputLoopCount++;
}
Debug.Assert(frameInfo_.LastPresentTime != 0);
Debug.Assert(frameInfo_.AccumulatedFrames != 0);
}
sw.Stop();
var frameCaptureTime = frameCount * TimeSpan.FromSeconds(1.0 / frameRate).Ticks;
frameCaptureTime = DateTime.Now.ToFileTimeUtc();
var aqTime = TimeSpan.FromSeconds((double)sw.ElapsedTicks / Stopwatch.Frequency);
totalAFMilliseconds += aqTime.TotalMilliseconds;
if (desktopResource != null)
using (var desktopTexture = desktopResource?.QueryInterface<Texture2D>())
{
Texture2D desktopTextureCopy = null;
try
{
desktopTextureCopy = textureAllocator.AllocateTexture();
}
catch (SharpDX.SharpDXException e)
{
var result = mDevice.DeviceRemovedReason;
result.CheckError();
throw e;
}
if (outputDuplication != null)
rgbToNv12.ConvertRGBToNV12(desktopTexture, desktopTextureCopy);
if (frameCount == 2)
timeStart = lastTimeStamp;
Console.WriteLine("Writing frame {0}", TimeSpan.FromTicks(frameCaptureTime - lastTimeStamp).ToString());
if (frameCount > 0)
{
var frameDuration = TimeSpan.FromSeconds(1.0 / frameRate).Ticks;
var time = (frameCount - 2) * frameDuration;
WriteFrame(sinkWriter, streamIndex, lastTimeStamp - timeStart, frameCaptureTime - lastTimeStamp, desktopTextureCopy.Description.Width, desktopTextureCopy.Description.Height, desktopTextureCopy, textureAllocator);
Console.WriteLine("frame written");
}
desktopTextureCopy.Dispose();
}
lastTimeStamp = frameCaptureTime;
CaptureTime = TimeSpan.FromTicks(lastTimeStamp - timeStart);
if (CaptureFramesChanged != null)
{
CaptureFramesChanged.Invoke(null, new EventArgs());
}
Console.WriteLine("end of loop");
}
stopCapture = false;
Console.WriteLine("Total AquireFrame time: {0}", totalAFMilliseconds / (300 * (1000 / frameRate)));
Console.WriteLine("Begining finalise");
sinkWriter.Finalize();
}
}
}
}
}
}
}
}
}
}
MediaManager.Shutdown();
}
谢谢
答案 0 :(得分：1)
我修复了它。似乎这是一个多线程问题，并通过添加以下行得以解决：
using(var multiThread = mDevice.QueryInterface<Multithread>())
{
multiThread.SetMultithreadProtected(true);
}
在创建设备之后。