Multi NDI Recorder

A Qt 6 desktop utility for Windows that records multiple NDI sources in parallel with continuous or segmented MP4 output and a built-in recordings browser.

Features at a glance

• Configure 1–10 NDI inputs, each with preview, start/stop/pause controls, and a per-source timer; global Start/Pause/Stop manage every recorder at once.
• Per-source settings dialog to pick NDI source, output folder, labeling, and continuous vs. segmented recording durations.
• Native-resolution H.264 MP4 writing with optional time-based segment rollover handled by the FFmpeg pipeline.
• Recording library tab lists completed files with open/reveal actions, plus simple metadata scanning.
• Lightweight logging to logs/app.log for capture and muxing events.

Prerequisites (install first)

• Windows 10/11 64-bit with the Desktop development with C++ workload from Visual Studio 2019/2022 (MSVC, Windows SDK, CMake, and Ninja if desired).
• Qt 6 (Widgets): install a matching MSVC build (e.g., 6.5+). Note the CMAKE_PREFIX_PATH to its lib/cmake directory.
• NDI 5 SDK: install and record the Include and Lib/x64 directories.
• FFmpeg dev libraries built for MSVC with import libraries (avformat, avcodec, avutil, swscale) and headers available.

Configure and build

1. Open a x64 Native Tools developer prompt for your Visual Studio version.
2. Clone this repository and enter it:

   git clone <repo-url>
   cd multi-ndi-recorder

3. Configure CMake with your dependency paths (adjust as needed):

   cmake -S . -B build -G "Ninja" \
     -DNDI_SDK_INCLUDE="C:/Program Files/NDI SDK/Include" \
     -DNDI_SDK_LIB="C:/Program Files/NDI SDK/Lib/x64" \
     -DFFMPEG_INCLUDE="C:/ffmpeg/include" \
     -DFFMPEG_LIB="C:/ffmpeg/lib" \
     -DCMAKE_PREFIX_PATH="C:/Qt/6.5.2/msvc2019_64/lib/cmake"

   You can replace Ninja with "Visual Studio 17 2022" -A x64 if you prefer an IDE solution. The placeholder paths correspond to the cache variables exposed in CMakeLists.txt.

4. Build the application:

   cmake --build build --config Release

5. Run the app (from the build tree or after installation):

   build/Release/MultiNdiRecorder.exe

Using the application

1. Set source count: Use the spin box at the top to choose how many NDI tiles to display (1–10). Tiles show preview, status, and an elapsed timer.
2. Configure each source: Click Settings on a tile to pick the NDI source, output folder, label, and continuous vs. segmented duration. Press Refresh to rescan sources.
3. Start recording: Hit Start on a tile or Start All for every source. Pause/Resume keeps the file active; Stop finalizes it. Segmented mode automatically rolls over files at the chosen minute interval.
4. Library tab: Switch to the Recordings tab to see captured files. Double-click Open to launch in the default player or Reveal to highlight in Explorer.
5. Logs: Review logs/app.log for capture, NDI, and FFmpeg events when diagnosing issues.

Notes and tips

• Ensure output folders exist and are writable before starting a session.
• NDI and FFmpeg binaries must be discoverable at run time (e.g., via PATH or next to the executable) so their dependent DLLs load correctly.
• For best disk stability, record to fast local storage rather than network shares.