DisplayFlow/demo/windows_sender/README.md

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).
3. Network Transmission using UDP.

Prerequisites

• Windows 10/11
• Visual Studio 2019 or later (with C++ Desktop Development)
• CMake 3.10+

Build

1. Open a terminal (Developer Command Prompt for VS).
2. Navigate to this directory:

   cd demo\windows_sender
   

3. Create a build directory:

   mkdir build
   cd build
   

4. Configure and Build:

   cmake ..
   cmake --build . --config Release
   

Run

Run the executable with target IP and Port (optional):

.\Release\WindowsSenderDemo.exe <TargetIP> <Port>

Example:

.\Release\WindowsSenderDemo.exe 192.168.1.100 8888

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).
• NetworkSender: Fragments the H.264 stream into UDP packets (MTU ~1400 bytes) and sends them to the target.

Protocol

The demo uses a simple custom protocol for feasibility verification:

• Packet Header (Network Layer): FrameID (4B), FragID (2B), TotalFrags (2B).
• Frame Header (Application Layer, in first fragment/reassembled): Timestamp (8B), Width (4B), Height (4B), Type (4B), Size (4B).
• Payload: H.264 NAL units.