opencv中播放视频窗口大小与原视频不一致怎么办

可以使用cv2.resize()函数改变窗口大小，如下：

import cv2

cap = cv2.VideoCapture("video.mkv")

# 获取原视频大小
width = int(cap.get(cv2.CAP_PROP_FRAME_WIDTH))
height = int(cap.get(cv2.CAP_PROP_FRAME_HEIGHT))

# 改变目标窗口大小
new_width = 800
new_height = 600

# 创建视频窗口
cv2.namedWindow("Video", cv2.WINDOW_NORMAL)
cv2.resizeWindow("Video", new_width, new_height)

while True:
    ret, frame = cap.read()

    if ret:
        # 将帧大小调整为目标窗口大小
        frame = cv2.resize(frame, (new_width, new_height))

        # 显示帧
        cv2.imshow("Video", frame)

        # 按下q键退出循环
        if cv2.waitKey(25) & 0xFF == ord("q"):
            break
    else:
        break

cap.release()
cv2.destroyAllWindows()