树莓派Python直接操控摄像头

https://www.raspberrypi.org/blog/picamera-pure-python-interface-for-camera-module/

If you have a Raspberry Pi camera module, you’ve probably used raspistilland raspivid, which are command line tools for using the camera. Dave Jones, a Database Admin, software developer and SQL know-it-all based in Manchester has been working on an equivalent, feature complete implementation of these in Python. This means you can access the camera module directly from a Python script, without using os.system or executing a subprocess.

At Oggcamp I set up a big TV with a Pi and camera taped on top. I SSH’d in to the Pi from my laptop and entered commands in to iPython using picamera.

Speaking as an avid Pythonist, picamera’s implementation is beautiful and it really is a wonderful library to use. It works really well for demonstrations using the Pi camera, and for real world applications. Part of the appeal of the Raspberry Pi is that you can work on embedded electronics projects without needing to know low-level languages or have to program a microprocessor – instead you have the choice of a range of accessible high-level languages such as Python – and this is an extension of that kind of abstraction, which open up a world of possibilities to a wider diversity of makers.

Example usage:

import picamera
from time import sleep

camera = picamera.PiCamera()
camera.capture('image.jpg')

camera.start_preview()
camera.vflip = True
camera.hflip = True
camera.brightness = 60

camera.start_recording('video.h264')
sleep(5)
camera.stop_recording()

Also you can do things like this:

for i in range(100):
    camera.brightness = i
    sleep(0.1)

and watch the preview flow through the brightness levels.

The library has many configurations – you can change the brightness, contrast, saturation, image effects, exposure modes and such, as well as optionally show a live preview of the camera’s view. You can capture single images and sequences of images as well as video streams.

Here’s a presentation of picamera Dave gave at Manchester Raspberry Jam XVI – where he demonstrates the basic usage of the module by typing commands in to a Python prompt on his laptop, with a monitor displaying the camera output (unfortunately out of shot in the video):