树莓派PiCamera库的基本使用

本篇先从最基本的应用开始讲起，再详细介绍一些更高阶的设定。内容说明操作系统Raspberry Pi OSIDEThonny Python IDE1. 基本实现from picamera import PiCamerafrom time import sleepcamera = PiCamera()camera.start_preview()# 树莓派上显示视频camera.start_record

橙橙小狸猫

6703人浏览 · 2022-04-13 16:40:09

橙橙小狸猫 · 2022-04-13 16:40:09 发布

本篇先从最基本的应用开始讲起，再详细介绍一些更高阶的设定。

内容	说明
操作系统	Raspberry Pi OS
IDE	Thonny Python IDE

1. 基本实现

from picamera import PiCamera
from time import sleep
with PiCamera() as camera:
	camera.start_preview()  # 树莓派上显示视频
	camera.start_recording('/home/pi/Desktop/video.h264')  # 存储视频到相应的文件夹下
	sleep(5)
	camera.stop_recording()  # 停止存储
	camera.stop_preview()  # 停止显示

函数start_recording()支持的视频格式如下：
‘h264’ - Write an H.264 video stream
‘mjpeg’ - Write an M-JPEG video stream
‘yuv’ - Write the raw video data to a file in YUV420 format
‘rgb’ - Write the raw video data to a file in 24-bit RGB format
‘rgba’ - Write the raw video data to a file in 32-bit RGBA format
‘bgr’ - Write the raw video data to a file in 24-bit BGR format
‘bgra’ - Write the raw video data to a file in 32-bit BGRA format

2. 高阶设定

基本设置

设置内容	代码	说明
分辨率	`camera.resolution = (1920, 1080)`	静态照片的最大分辨率为2592×1944，视频录制的最大分辨率为1920×1080。最低分辨率为64×64。
每秒帧数	`camera.framerate = 30`

画面设置

设置内容	代码	说明
旋转	`camera.rotation = 0`
水平翻转	`camera.vflip = False`
垂直翻转	`camera.hflip = False`
添加文字	`camera.annotate_text = "Hello world!"`
更改添加文本的外观	`camera.annotate_text_size = 50`
图像稳定	`camera.video_stabilization = False`	当设置为 True 时，这会打开视频稳定功能。仅当摄像头模块在录制时移动时才需要此功能，例如，如果它连接到机器人或被携带，以减少捕获视频的抖动。
裁剪图片	`camera.crop = (0.0, 0.0, 1.0, 1.0)`

画面效果

设置内容	代码	说明
饱和度	`camera.saturation = 0`
亮度	`camera.brightness = 50`	取值范围： 0 and 100；默认值是 50
阴影	`camera.sharpness = 0`
对比度	`camera.contrast = 0`	这将设置图像的对比度。较高的数字将使事情看起来更加戏剧化和鲜明; 较低的数字将使事情看起来更加褪色。您可以使用100之间的任何数字来获得最小对比度，并使用100来获得最大对比度。
色彩效果	`camera.color_effects = None`	This changes the colour effect currently in use by the camera. Normally, this setting should be left alone, but if you provide a pair of numbers you can alter the way the camera records colour: try (128, 128) to create a black and white image.
调节模式	`camera.awb_mode = 'auto'`	This sets the automatic white balance mode of the camera, and can be set to any one ofthe following modes: off, auto, sunlight, cloudy, shade, tungsten, fluorescent, incandescent, flash, or horizon. If you find your pictures and videos look a little blue or yellow, try a different mode.
补光	`camera.exposure_compensation = 0`	This sets the exposure compensation of the camera, allowing you to manually control how much light is captured for each image. Unlike changing the brightness setting, this actually controls the camera itself. Valid values range from -25 for a very dark image to 25 for a very bright image.
曝光	`camera.exposure_mode = 'auto'`	This sets the exposure mode, or the logic the Camera Module uses to decide how an image should be exposed. Possible modes are: off, auto, night, backlight, spotlight, sports, snow, beach, verylong, fixedfps, antishake, and fireworks.
曝光光亮	`camera.meter_mode = 'average'`	This controls how the camera decides on the amount of available light when setting its exposure. The default averages the amount of light available throughout the whole picture; other possible modes are backlit, matrix, and spot.
图像效果	`camera.image_effect = 'none'`	图片效果：可选 blur, cartoon, colorbalance, colorpoint, colorswap, deinterlace1, deinterlace2, denoise, emboss, film, gpen, hatch, negative, none, oilpaint, pastel, posterise, saturation, sketch, solarize, washedout, and watercolor.
IOS	`camera.ISO = 0`	This changes the ISO setting of the camera, which affects how sensitive it is to light. By default, the camera adjusts this automatically depending on the available light. You can set the ISO yourself using one of the following values: 100, 200, 320, 400, 500, 640, 800. The higher the ISO, the better the camera will perform in low-light environments but the grainier the image or video it captures.