PythonのOpenCVで動画ファイルから指定フレームを画像として抽出

#!/usr/bin/env python3
import cv2

file = "H:\py\sample.mov"

vc = cv2.VideoCapture(file)

frame_cnt = int(vc.get(cv2.CAP_PROP_FRAME_COUNT)) # フレーム数
fps = int(vc.get(cv2.CAP_PROP_FPS)) # FPS

print("frames:{0},fps:{1}".format(frame_cnt, fps))

ret, img = vc.read()
if not ret:
    quit()  # 終了

cv2.imwrite("frame.png", img)

frame_pos = int(vc.get(cv2.CAP_PROP_POS_FRAMES)) 
print("frame_pos:{0}/{1}".format(frame_pos, frame_cnt))

# 500フレーム目に移動
vc.set(cv2.CAP_PROP_POS_FRAMES, 500)
frame_pos = int(vc.get(cv2.CAP_PROP_POS_FRAMES)) 
print("frame_pos:{0}/{1}".format(frame_pos, frame_cnt))

ret, img = vc.read()
if not ret:
    quit()  # 終了

cv2.imwrite("frame500.png", img)

vc.release()