RAW-MIPI-AR0234M配置为4lane模式

veye_xumm

@lizi
我测了一下orin nano上面，实际采集数据的帧率是没有问题的。你可以延长你的代码的统计时间到10秒，100秒，可以发现帧率会趋近于接近60fps。

那么为何出现你只统计1秒的时候，帧率只有20帧的结果呢？我进行了一下简单的时间分析，发现是第一次调用cap.read()函数的时候，耗时大约半秒左右。（估计是底层进行buffer的初始化之类的操作。）

可以参考我贴上来这个代码：

import cv2
import argparse
import subprocess
import time

def main():
    # Set up command-line argument parser
    parser = argparse.ArgumentParser(description='Real-time display of GREY image from /dev/video0')
    parser.add_argument('--roix', type=int, default=0, help='roi start x (default: 0)')
    parser.add_argument('--roiy', type=int, default=0, help='roi start y (default: 0)')
    parser.add_argument('--width', type=int, default=1920, help='image width (default: 640)')
    parser.add_argument('--height', type=int, default=1200, help='image height (default: 480)')
    parser.add_argument('--fps', type=int, default=60, help='frame rate (default: 30)')
    args = parser.parse_args()
    
    v4l2_cmd = f"v4l2-ctl --set-ctrl roi_x={args.roix}"
    subprocess.run(v4l2_cmd, shell=True)
    
    v4l2_cmd = f"v4l2-ctl --set-ctrl roi_y={args.roiy}"
    subprocess.run(v4l2_cmd, shell=True)
    
    v4l2_cmd = f"v4l2-ctl --set-fmt-video=width={args.width},height={args.height}"
    subprocess.run(v4l2_cmd, shell=True)
    
    v4l2_cmd = f"v4l2-ctl --set-ctrl frame_rate={args.fps}"
    subprocess.run(v4l2_cmd, shell=True)
    
    # Open the /dev/video0 device
    cap = cv2.VideoCapture('/dev/video0')
    if not cap.isOpened():
        print("Failed to open video device")
        return

    # Set the image size
    cap.set(cv2.CAP_PROP_FRAME_WIDTH, args.width)
    cap.set(cv2.CAP_PROP_FRAME_HEIGHT, args.height)

    frame_num = 0
    
    # Loop over frames and display them
    while True:
        # Read a frame
        ret, frame = cap.read()
        # Check if reading was successful
        if ret:
            if frame_num == 0:
                time_start = time.perf_counter()
            frame_num += 1
            # Display the frame
            # cv2.imshow('VEYE MV camera GREY image preview', frame)
            print(f"Success save , {frame_num}")
        else:
            print("Failed to read frame")
            #break

        time_end = time.perf_counter()
        time_ms = (time_end - time_start)*1000
        print(time_ms)
        if time_ms > 1000:
            print(frame_num)
            break

        # Exit if 'q' key is pressed
        if cv2.waitKey(1) & 0xFF == ord('q'):
            break

    # Release resources
    cap.release()
    cv2.destroyAllWindows()

if __name__ == '__main__':
    main()