simple client photograph to socket in PI (use picamera）

photographToClientSocket.py

import io
import socket
import struct
import time
import picamera
from PIL import Image
import cv2
import numpy as np

def photographToFile():
    # Explicitly open a new file called my_image.jpg
    my_file = open('photo.jpg', 'wb')
    with picamera.PiCamera() as camera:
        camera.start_preview()
        time.sleep(2)
        camera.capture(my_file)
        # Note that at this point the data is in the file cache, but may
        # not actually have been written to disk yet
    my_file.close()
    # Now the file has been closed, other processes should be able to
    #read the image successfully

    return True

def photographToBytesIO():
    #write stream to BytesIO(Python’s in-memory stream class)
    stream = io.BytesIO()
    with picamera.PiCamera() as camera:
        camera.start_preview()
        time.sleep(2)
        camera.capture(stream, format='jpeg')
    # "Rewind" the stream to the beginning so we can read its content
    stream.seek(0)
    image = Image.open(stream)

    return image
def photographToCV():
    # Create the in-memory stream
    stream = io.BytesIO()
    with picamera.PiCamera() as camera:
        camera.start_preview()
        time.sleep(2)
        camera.capture(stream, format='jpeg')
    # Construct a numpy array from the stream
    data = np.fromstring(stream.getvalue(), dtype=np.uint8)
    # "Decode" the image from the array, preserving colour
    image = cv2.imdecode(data, 1)
    # OpenCV returns an array with data in BGR order. If you want RGB instead
    # use the following...
    image = image[:, :, ::-1]

    return image

def photographSeq():
    with picamera.PiCamera() as camera:
        camera.start_preview()
        time.sleep(2)
        for filename in camera.capture_continuous('img{counter:03d}.jpg'):
            print('Captured %s' % filename)
            time.sleep(300) # wait 5 minutes

def photographToClientSocket():
    # Connect a client socket to my_server:8000 (change my_server to the hostname of your server)
    client_socket = socket.socket()
    #client_socket.connect(('my_server', 8000))
    client_socket.connect(('192.168.1.102', 8000))

    # Make a file-like object out of the connection
    connection = client_socket.makefile('wb')
    try:
        with picamera.PiCamera() 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()
       
      
if __name__ == '__main__':
    photographToFile()

    image = photographToBytesIO()
    print(image)
    time.sleep(3)

    image = photographToCV()
    print(image)
    time.sleep(3)

    #photographSeq()

    photographToClientSocket()