初始化相機時出現Python Video Streaming初學者錯誤

Question

我想在樹莓派USB攝像頭和筆記本電腦之間制作視頻流

客戶：

import io
import socket
import struct
import time
import pygame.camera

# Connect a client socket to my_server:8000 (change my_server to the
# hostname of your server)
client_socket = socket.socket()
client_socket.connect(('192.168.1.12', 8000))

# Make a file-like object out of the connection
connection = client_socket.makefile('wb')
try:
    with pygame.camera.Camera ()as camera:
        camera.resolution = (640, 480)
        # Start a preview and let the camera warm up for 2 seconds
        camera.start_preview()
        time.sleep(2)

        # Note the start time and construct a stream to hold image data
        # temporarily (we could write it directly to connection but in this
        # case we want to find out the size of each capture first to keep
        # our protocol simple)
        start = time.time()
        stream = io.BytesIO()
        for foo in camera.capture_continuous(stream, 'jpeg'):
            # Write the length of the capture to the stream and flush to
            # ensure it actually gets sent
            connection.write(struct.pack('<L', stream.tell()))
            connection.flush()
            # Rewind the stream and send the image data over the wire
            stream.seek(0)
            connection.write(stream.read())
            # If we've been capturing for more than 30 seconds, quit
            if time.time() - start > 30:
                break
            # Reset the stream for the next capture
            stream.seek(0)
            stream.truncate()
    # Write a length of zero to the stream to signal we're done
    connection.write(struct.pack('<L', 0))
finally:
    connection.close()
    client_socket.close()

但是我有這個

錯誤：追蹤（最近一次通話）：

  File "camera.py", line 15, in <module> with pygame.camera.Camera ()as camera:
  File "/usr/lib/python2.7/dist-packages/pygame/camera.py", line 100, in __init__
    _check_init()
  File "/usr/lib/python2.7/dist-packages/pygame/camera.py", line 86, in _check_init raise     ValueError("Need to call camera.init() before using.")
  ValueError: Need to call camera.init() before using.

我是這種編程語言的新手，所以我不明白如何安裝相機以使用它及其功能。我在網上找到了一些教程，但是在代碼中沒有出現錯誤的部分。

Answer 1

發生這種情況是因為您沒有在調用Camera（）之前初始化pygame

首先，請確保您導入所需的所有內容：

import pygame
import pygame.camera
from pygame.locals import *

現在，您必須初始化pygame和pygame.camera：

pygame.init()
pygame.camera.init()

最后像您一樣創建Camera對象：

with pygame.camera.Camera ()as camera:
   blablabla...