增加windows端屏幕捕获编码demo

demo/windows_sender/ScreenCapture.h

@@ -0,0 +1,27 @@
+#pragma once
+
+#include <d3d11.h>
+#include <dxgi1_2.h>
+#include <wrl/client.h>
+#include <memory>
+
+using Microsoft::WRL::ComPtr;
+
+class ScreenCapture {
+public:
+    ScreenCapture();
+    ~ScreenCapture();
+
+    bool Initialize();
+    bool CaptureFrame(ComPtr<ID3D11Texture2D>& texture);
+    void ReleaseFrame();
+    
+    ID3D11Device* GetDevice() const { return device_.Get(); }
+    ID3D11DeviceContext* GetContext() const { return context_.Get(); }
+
+private:
+    ComPtr<ID3D11Device> device_;
+    ComPtr<ID3D11DeviceContext> context_;
+    ComPtr<IDXGIOutputDuplication> duplication_;
+    bool frame_acquired_ = false;
+};