Chapter 3: Camera Basics
Chapter goal: Understand the NanoCam's camera data pipeline and get to know the AI modes built into the firmware.
Principle
The NanoCam connects to the camera through the DVP (Digital Video Port) interface. The GC2145 sensor outputs 8-bit parallel pixel data; the ESP32-S3's LCD_CAM peripheral stores it directly into PSRAM via DMA, and the HTTP server then streams it to the browser in MJPEG format.
Key Concepts
- DVP: 8 parallel data lines + 3 synchronization signals (VSYNC/HREF/PCLK)
- MJPEG: each frame is an independent JPEG image; the browser loads them continuously to create a video effect
- PSRAM: 8MB PSRAM used as the frame buffer, holding 2-4 frames
Steps
3.1 Viewing the Default Image
After flashing, the firmware is in streaming mode by default; open http://<IP> in a browser to see the image.
| Command | Function |
|---|---|
| ai_mode:0\r | Video transmission module |
| ai_mode:1\r | Cat face detection |
| ai_mode:2\r | Face detection |
| ai_mode:3\r | Color recognition |
| ai_mode:4\r | Face recognition |
| ai_mode:5\r | QR code scanning |
For the complete AI modes and serial commands, see the Serial Protocol Manual.
Next chapter: Chapter 4: Face Detection