# Webcam viewer

> A webcam viewer in Python — the live picture, a snapshot button that saves PNG files and the measured frame rate, with OpenCV, ffmpeg or a test pattern.

Source: https://albakore.github.io/pyzed/audio/demos/webcam/

(Image: The live picture of a camera with a frame rate badge)

A camera app in 50 lines: [`examples/audio/webcam.py`](https://github.com/albakore/pyzed/blob/main/examples/audio/webcam.py).

```bash
python examples/audio/webcam.py         # the default camera
python examples/audio/webcam.py test    # moving color bars, without a camera
```

**Snapshot** saves the current picture as a PNG next to the script, **Pause** freezes it.

```python
from pyzed import camera, ui

cam = camera.Camera(0, width=1280, height=720, mirror=True)
cam.start()

def view(self):
    return pz.column([
        ui.camera.Webcam(camera=cam, width=720, height=405, radius=10),
        ui.button("Snapshot", lambda: cam.snapshot("photo.png")),
    ])
```

The camera is read on its own thread; each new picture asks the window to redraw, so the app
needs no timer. It uses OpenCV when it is installed (`pip install opencv-python`), else the
`ffmpeg` program, else the test pattern. See [Webcam](https://albakore.github.io/pyzed/audio/components/webcam/) for every
option.