我想从指定的帧开始视频

Question

我想从一个指定的数字开始一段视频，我正在使用函数cv2.VideoCapture.set(cv2.CAP_PROP_POS_FRAMES, x)设置一个帧数，但它不起作用

w1 = Scale(f1, to=400, orient=tk.HORIZONTAL, length = 400)
w1.bind("<Button-1>", goto_frame)
w1.set(x)
w1["to"] = count_frames('my_video.avi')
w1.pack(side = LEFT)

class Scale(ttk.Scale):
    """a type of Scale where the left click is hijacked to work like a right click"""
    def __init__(self, master=None, **kwargs):
        ttk.Scale.__init__(self, master, **kwargs)
        self.bind('<Button-1>', self.set_value)

    def set_value(self, event):
        global count
        global x
        pause_video()
        self.event_generate('<Button-3>', x=event.x, y=event.y)
        frame_count = w1.get()
        print('w1 set to',w1.get())
        count = int(frame_count)
        time.sleep(2)
        cap2.set(cv2.CAP_PROP_POS_FRAMES, count)
        resume_video()
        #return 'break'

这里我想从cap2.set（cv2.CAP\u PROP\u POS\u FRAMES，count）函数中的count开始视频。 但是它提高了avi视频的播放速度，却没有从指定的计数帧开始播放