基于python + opencv的视频播放调节功能

import numpy as np

import cv2

import time

start_brightness = 0.1

count_keyu = 0

count_keyd = 0  

count_keyz = 0

count_keyj = 0

delay_time = 0

#——————————————————————————————播放视频——————————————————————

#————————添加自己的视频播放路径———————————

video_path="D:/python_test/opao_timeX0.1.mp4"

# 创建一个视频读写类

video_capture=cv2.VideoCapture(video_path)

#读取视频的fps,  大小   每秒传输帧数

fps=video_capture.get(cv2.CAP_PROP_FPS)

size=(video_capture.get(cv2.CAP_PROP_FRAME_WIDTH),video_capture.get(cv2.CAP_PROP_FRAME_HEIGHT))

#print("fps: {}\nsize: {}".format(fps,size))

#读取视频时长（帧总数）

total = int(video_capture.get(cv2.CAP_PROP_FRAME_COUNT))

#print("[INFO] {} total frames in video".format(total))

#设定从视频的第几帧开始读取

#From :  https://blog.csdn.net/luqinwei/article/details/87973472

frameToStart = 00

video_capture.set(cv2.CAP_PROP_POS_FRAMES, frameToStart);

#显示视频

current_frame=frameToStart

while  True:

    success, frame = video_capture.read()   

    time.sleep(0.0267)

   # cv2.waitKey(40)    

    if  success == False:

        break

#设置延时，降低播放速度

#    time.sleep(0.0188)

#自定义图像大小

    h, w = frame.shape[:2]  # 三通道

    size = (int(w * 1.0), int(h * 1.0))

    frame = cv2.resize(frame, size)

#显示当前视频已播放时间和总时间

#计算当前时间

    now_seconds=int(current_frame /fps%60)

    now_minutes=int(current_frame/fps/60)

    total_second=int(total /fps%60)

    total_minutes=int(total/fps/60)

#   { <参数序号> : <填充> <对齐）> <宽度> <,> <.精度> <类型>}.

Time_now_vs_total="Time:{:>3}:{:>02}|{:>3}:{:0>2}".format(now_minutes,now_seconds,total_minutes,total_second)

    print(Time_now_vs_total)

#--------键盘控制视频---------------

    #读取键盘值

    key = cv2.waitKey(1) & 0xff

    #按键z增长延时，j减少延时。“zeng”、“jian”,实现在增长到值开始建

    if key == ord("z"):

        count_keyz += 1

        delay_time = 0 + 0.02 * count_keyz

        if(delay_time>1.0):

            delay_time = 1.0

    if key == ord("j"):

            count_keyj += 1

            delay_time = delay_time - 0.02 * count_keyj

            if(delay_time<0):

                delay_time = 0

            time.sleep(delay_time)

#    print(delay_time)

    time.sleep(delay_time)

    #设置空格按下时暂停

    if key == ord(" "):

        cv2.waitKey(1)

    #设置Q按下时退出

    if key == ord("q"):

        break

    #按下U，上升计数器加1，表示亮度增加，即UP

    if key == ord("u"):

        count_keyu +=1

     #   print(count_keyu)

        brightness  = start_brightness + count_keyu * 0.3

      #  print(brightness)

        if(brightness>2):

            brightness = 1.9

            count_keyu = 0            

        #确保brightness的结果是保留一位小数，计算时经常出现0.00000000000000009或0.00000000000000001的误差

        brightness_str =format(brightness, '.1f')            

        new_video_path = video_path[:25]+brightness_str+'.mp4'

        video_capture = cv2.VideoCapture(new_video_path)

        frameToStart = now_seconds * fps

        video_capture.set(cv2.CAP_PROP_POS_FRAMES, frameToStart);

        print(new_video_path)

    #按下D，下降计数器加1，表示亮度下调，即down

    if key == ord("d"):

         count_keyd += 1

         brightness = start_brightness + count_keyu * 0.3 - count_keyd * 0.3  #表示亮度的变量

         if(brightness

             brightness = 0.1

             count_keyd = 0       

         #确保brightness的结果是保留一位小数，计算时经常出现0.00000000000000009或0.00000000000000001的误差

         brightness_str = format(brightness, '.1f')  

         new_video_path = video_path[:25]+brightness_str+'.mp4'

         video_capture=cv2.VideoCapture(new_video_path)

         frameToStart = now_seconds * fps

         video_capture.set(cv2.CAP_PROP_POS_FRAMES, frameToStart);

#         print(new_video_path)

    #  putText(img, text, org, fontFace, fontScale, color, thickness=None, lineType=None, bottomLeftOrigin=None):

    cv2.putText(frame,Time_now_vs_total,(300,50),cv2.FONT_HERSHEY_SIMPLEX,2,(0,0,255),3)

    cv2.imshow("frame",frame)

    #人工对视频帧数进行计数

    current_frame += 1

video_capture.release()