junkpile

Junkpile 40 — wgpu Network Output

A native Tauri 2 + wgpu example that publishes one authoritative GPU frame through UDP/MPEG-TS, RTSP/TCP, or RTMP/FLV without blocking the renderer.

Run

npm install
npm run dev

Protocols

UDP / MPEG-TS

No server is required.

Publisher:

udp://127.0.0.1:23000?pkt_size=1316&buffer_size=1048576

VLC receiver:

udp://@:23000

Run destination preflight before starting. The preflight binds a local UDP receiver, sends a short synthetic MPEG-TS stream through FFmpeg, and confirms that packets arrive.

RTSP / TCP

Start MediaMTX first:

mediamtx ./tools/mediamtx.yml

Default publisher and reader URL:

rtsp://127.0.0.1:8554/junkpile40

RTMP / FLV

With the same MediaMTX process running:

rtmp://127.0.0.1:1935/junkpile40

RTSP and RTMP preflight first test TCP reachability, then publish a short synthetic FFmpeg stream. A 400 Bad Request is therefore shown before live GPU capture begins. Common causes are authentication, a restricted path, or another publisher already occupying the same path.

Architecture

wgpu texture
  → 3 asynchronous readback buffers
  → 3 reusable CPU RGBA buffers
  → bounded 2-frame queue
  → one supervised FFmpeg process

The app sends one black bootstrap frame during startup so FFmpeg must create the network header before the UI reports the output as active.

Diagnostics

• full FFmpeg command with credentials redacted
• retained FFmpeg stderr lines
• FFmpeg PID and exit code
• capture requests and completed GPU readbacks
• GPU, CPU-pool, and worker drops
• queue pressure
• raw frame bandwidth and total bytes written

Important

VLC is a reader. It is not the RTSP or RTMP ingest server. UDP is the only direct sender-to-reader path in this example.

This site is open source. Improve this page.