更新捕获视频保存到文件和更新编译方法

demo/windows_sender/README.md

@@ -1,20 +1,24 @@
 # Windows Sender Demo
 
 This is a simplified demo of the Windows Host sender for DisplayFlow.
+
 It demonstrates:
 1. Screen Capture using Desktop Duplication API (DXGI).
-2. Hardware H.264 Encoding using Media Foundation (MF).
+2. Hardware/Software H.264 Encoding using **FFmpeg** (switched from Media Foundation for better compatibility).
 3. Network Transmission using UDP.
 
 ## Prerequisites
 
 - Windows 10/11
-- Visual Studio 2019 or later (with C++ Desktop Development)
+- Visual Studio 2022 or later (with C++ Desktop Development)
 - CMake 3.10+
+- **FFmpeg Development Libraries** (Shared)
+  - Ensure you have the `include` and `lib` directories.
+  - Example path: `D:\tools\ffmpeg-8.0.1-full_build-shared`
 
 ## Build
 
-1. Open a terminal (Developer Command Prompt for VS).
+1. Open a terminal (Developer Command Prompt for VS or PowerShell).
 2. Navigate to this directory:
    ```cmd
    cd demo\windows_sender
@@ -24,30 +28,49 @@ It demonstrates:
    mkdir build
    cd build
    ```
-4. Configure and Build:
+4. Configure and Build (Replace path with your FFmpeg location):
    ```cmd
-   cmake ..
+   cmake .. -DFFMPEG_ROOT="D:/tools/ffmpeg-8.0.1-full_build-shared"
    cmake --build . --config Release
    ```
+   *Note: If your FFmpeg is installed elsewhere, change the path accordingly.*
+
+5. **Important**: Copy FFmpeg DLLs to the executable directory.
+   - Copy `avcodec-*.dll`, `avutil-*.dll`, `swscale-*.dll`, `avformat-*.dll` from your FFmpeg `bin` directory to `demo\windows_sender\build\Release`.
 
 ## Run
 
-Run the executable with target IP and Port (optional):
+Run the executable with optional arguments: Target IP, Port, and Output File.
 
 ```cmd
-.\Release\WindowsSenderDemo.exe <TargetIP> <Port>
+.\Release\WindowsSenderDemo.exe [TargetIP] [Port] [OutputFile]
 ```
 
-Example:
-```cmd
-.\Release\WindowsSenderDemo.exe 192.168.1.100 8888
-```
+### Examples
+
+1. **Basic Streaming** (Default: 127.0.0.1:8888):
+   ```cmd
+   .\Release\WindowsSenderDemo.exe
+   ```
+
+2. **Specify Target**:
+   ```cmd
+   .\Release\WindowsSenderDemo.exe 192.168.1.100 8888
+   ```
+
+3. **Stream and Save to File** (for debugging):
+   ```cmd
+   .\Release\WindowsSenderDemo.exe 127.0.0.1 8888 debug.h264
+   ```
+   You can play the saved `debug.h264` using VLC player to verify the encoding quality.
 
 ## Implementation Details
 
 - **ScreenCapture**: Uses `IDXGIOutputDuplication` to capture desktop frames.
-- **VideoEncoder**: Uses `IMFTransform` (Media Foundation) to encode frames to H.264. 
-  - *Note*: This demo attempts to feed RGB32 textures to the encoder. If the hardware encoder only supports NV12, conversion logic is needed (not fully implemented in this minimal demo).
+- **VideoEncoder**: 
+  - Uses **FFmpeg (libx264)** for encoding.
+  - Performs **BGRA to YUV420P** color conversion using `libswscale`.
+  - Configured for low latency (`zerolatency` tune, `ultrafast` preset).
 - **NetworkSender**: Fragments the H.264 stream into UDP packets (MTU ~1400 bytes) and sends them to the target.
 
 ## Protocol