openmv持续拍摄照片串口发送至电脑，电脑持续打开窗口显示照片

程序运行流程为：

1. 运行PC端代码，电脑等待串口接收图片数据
2. 波特率最高921600
3. 运行openmv代码，openmv使用snapshot方法采集一张图片，进行压缩并发送
4. 电脑收到图片数据，解码为一张图片，并保存为jpg格式，发送#表示完成
5. openmv接收到#后停止发送图像

OPENMV端

import sensor, image, time, ustruct, pyb

def init_camera():
    sensor.reset()
    sensor.set_pixformat(sensor.JPEG)  # 直接设置为JPEG格式，减少压缩步骤
    sensor.set_framesize(sensor.QVGA)
    sensor.skip_frames(time=2000)

def send_image_via_uart(uart, img):
#    img_bytes = img.getbytes()
    length = len(img)
    uart.write(ustruct.pack("<I", length))  # 发送长度
    uart.write(img)  # 发送图片数据

def main():
    uart = pyb.UART(3, baudrate=921600, timeout=1000)
    init_camera()
    
    while True:
        img = sensor.snapshot()
        send_image_via_uart(uart, img)
        print("图片已发送")
        time.sleep(1)  # 添加延时，避免过快发送

if __name__ == "__main__":
    main()

PC端

import serial, struct, tkinter as tk, PIL.Image, PIL.ImageTk, io, threading

class ImageReceiver(threading.Thread):
    def __init__(self, serial_port):
        threading.Thread.__init__(self)
        self.ser = serial.Serial(serial_port, 921600, timeout=1)
        self.root = tk.Tk()
        self.root.title("接收并显示OpenMV图片")
        self.image_label = tk.Label(self.root)
        self.image_label.pack()
        self.running = True

    def run(self):
        while self.running:
            self.receive_image()

    def receive_image(self):
        try:
            # 读取图片长度
            length_bytes = self.ser.read(4)
            if len(length_bytes) != 4:
                print("长度信息接收错误")
                return
            img_length = struct.unpack("<I", length_bytes)[0]
            
            # 读取图片数据
            img_bytes = bytearray()
            while len(img_bytes) < img_length:
                chunk = self.ser.read(min(img_length - len(img_bytes), 1024))
                if not chunk:
                    break
                img_bytes.extend(chunk)
            
            if len(img_bytes) != img_length:
                print("图片数据接收不完整")
                return
            
            # 显示图片
            self.display_image(img_bytes)
        except Exception as e:
            print(f"接收图片时发生错误: {e}")

    def display_image(self, img_bytes):
        try:
            img = PIL.Image.open(io.BytesIO(img_bytes))
            tk_img = PIL.ImageTk.PhotoImage(img)
            self.image_label.config(image=tk_img)
            self.image_label.image = tk_img  # 保持引用
        except Exception as e:
            print(f"显示图片时发生错误: {e}")

    def stop(self):
        self.running = False
        self.ser.close()
        self.root.quit()

if __name__ == "__main__":
    receiver = ImageReceiver('COM23')  # 根据你的串口名修改
    receiver.start()
    receiver.root.mainloop()
    receiver.stop()