时间：2022-07-19 10:18:12 | 栏目：Python代码 | 点击：次
由于pygame.movie.Movie.play() 只支持MPEG格式的视频，且 pygame版本大于1.9.5好像已经不支持这个模块了，所以决定使用与opencv读取视频帧的画面，利用pygame的surface刷新窗口。
有基础的小伙伴，代码还是很好理解，直接上代码
import pygame
from pygame.locals import *
import cv2
import sys
import time
FPS = 30
FramePerSec = pygame.time.Clock()
video_path = './Selected Stimuli/noaudio_c_001_critical_swerve.mp4'
video = cv2.VideoCapture(video_path)
pygame.init()
pygame.display.set_caption('OpenCV Video Player on Pygame')
screen = pygame.display.set_mode((1280, 720), 0, 32)
screen.fill([0,0,0])
num = 0
while True :
T1 = time.time()
ret, frame = video.read()
if ret == False:
print('Total Time:', time.time()-T0)
sys.exit()
frame = cv2.cvtColor(frame, cv2.COLOR_BGR2RGB)
frame = cv2.transpose(frame)
frame = pygame.surfarray.make_surface(frame)
screen.blit(frame, (0,0))
if num == 0:
T0 = time.time()
pygame.display.update()
FramePerSec.tick(FPS)
num += 1
print('freq time:{}, frame num: {}'.format(time.time()-T1, num))
for event in pygame.event.get():
if event.type == QUIT:
sys.exit()
但是存在一些问题，时间戳的耗时比视频默认时间更长。
按理说FramePerSec = pygame.time.Clock()是能够很好的控制总的时长，但是发现视频越长播放器的延迟时间越长
换成Ubuntu系统后，发现以上延迟的问题得到缓解，推测可能与Windows系统中的进程管理有关。但是视频时差别很明显，比如120s视频，实际播放时间只用了118.8s。推测可能是pygame.time.Clock()是确保单帧的刷新率与预设相同，但是由于每一帧都存在相同的时间误差，就导致误差累加的问题明显。
由于以上原因无法解决，增加了一个简单的控制逻辑后可有效控制视频播放的时间戳问题
import pygame
from pygame.locals import *
import cv2
import sys
import time
video_path = 'out1.avi'
video = cv2.VideoCapture(video_path)
FPS = int(round(video.get(cv2.CAP_PROP_FPS)))
FramePerSec = pygame.time.Clock()
Width = int(video.get(cv2.CAP_PROP_FRAME_WIDTH))
Height = int(video.get(cv2.CAP_PROP_FRAME_HEIGHT))
pygame.init()
pygame.display.set_caption('OpenCV Video Player on Pygame')
screen = pygame.display.set_mode((Width, Height), 0, 32)
screen.fill([0,0,0])
num = 0
while True :
if num == 0:
T0 = time.time()
if time.time()-T0 > num*(1./FPS):
ret, frame = video.read()
TimeStamp = video.get(cv2.CAP_PROP_POS_MSEC)
if ret == False:
print('Total Time:', time.time()-T0)
pygame.quit()
sys.exit()
frame = cv2.cvtColor(frame, cv2.COLOR_BGR2RGB)
frame = cv2.transpose(frame)
frame = pygame.surfarray.make_surface(frame)
screen.blit(frame, (0,0))
pygame.display.update()
num += 1
for event in pygame.event.get():
if event.type == QUIT:
sys.exit()