Dual-Channel Video Capture (UVC)
A USB Video Class (UVC) device that exposes two independent video streaming functions on a single device.
What it does
- Presents two UVC camera functions, both 128x96 at 10 fps.
- Stream 0 sends YUY2 (uncompressed) color bars; stream 1 sends MJPEG color-bar frames.
- Uses bulk streaming endpoints (
CFG_TUD_VIDEO_STREAMING_BULK). - Adopts the frame interval requested by the host at stream commit, per stream.
- Blinks the board LED to indicate USB state (not mounted / mounted / suspended).
USB Descriptors
| Interface | Class driver |
|---|---|
| 0–1 | UVC video (control + streaming) — YUY2 |
| 2–3 | UVC video (control + streaming) — MJPEG |
Configuration
Notable tusb_config.h settings:
#define CFG_TUD_VIDEO 2 // 2 video control interfaces
#define CFG_TUD_VIDEO_STREAMING 2 // 2 video streaming interfaces
#define CFG_TUD_VIDEO_STREAMING_EP_BUFSIZE 256
#define CFG_TUD_VIDEO_STREAMING_BULK 1 // bulk streaming endpoints
Building
CMake:
mkdir build && cd build
cmake -DBOARD=raspberry_pi_pico ..
cmake --build .
Make:
make BOARD=raspberry_pi_pico all
Try it
Two webcam devices appear on the host. On Linux, list them with v4l2-ctl --list-devices and open each with ffplay /dev/videoN or a camera app — one shows YUY2 color bars, the other MJPEG color bars.