Python：视频拆分成一帧一帧的图片 |
您所在的位置：网站首页 › ps怎么把视频导成单帧 › Python：视频拆分成一帧一帧的图片 |
Python：视频拆分成一帧一帧的图片
|
简介：在AI的数据集采集视频相关的测试中，可能需要将视频拆分成一帧一帧的图片进行保存，然后在从关键帧中定位问题或标注等。我们可以通过cv库对视频进行分成一帧帧的图片进行保存，相当于图片转视频的反向操作。 相关教程：Python：用ffmpeg多图转视频 源码： import cv2 import argparse import os def get_video_duration(filename): cap = cv2.VideoCapture(filename) if cap.isOpened(): rate = cap.get(5) frame_num = cap.get(7) duration = frame_num / rate return duration return -1 def parse_args(video_file, picture_path, default): parser = argparse.ArgumentParser(description='Process pic') parser.add_argument('--input', help='video to process', dest='input', default=None, type=str) parser.add_argument('--output', help='pic to store', dest='output', default=None, type=str) # default参数表示间隔多少帧截取一张图片 parser.add_argument('--skip_frame', dest='skip_frame', help='skip number of video', default=default, type=int) args = parser.parse_args(['--input', video_file, '--output', picture_path]) return args def process_video(i_video, o_video, num): cap = cv2.VideoCapture(i_video) num_frame = cap.get(cv2.CAP_PROP_FRAME_COUNT) expand_name = '.jpg' if not cap.isOpened(): print("Please check the path.") cnt = 0 count = 0 while 1: ret, frame = cap.read() cnt += 1 if cnt % num == 0: count += 1 cv2.imwrite(os.path.join(o_video, str(count) + expand_name), frame) if not ret: break if __name__ == '__main__': video_file = r"C:\xxxxx\betterPro\videos\duck.mp4" picture_path = r"C:\xxxxx\betterPro\picture" frame = 50 cap = cv2.VideoCapture(video_file) # get方法参数按顺序对应下表 CV_CAP_PROP_FRAME_COUNT frames_num = cap.get(7) video_duration = get_video_duration(video_file) print("拆分视频成图片数目为：", int(frames_num / frame)) args = parse_args(video_file, picture_path, default=frame) if not os.path.exists(args.output): os.makedirs(args.output) process_video(args.input, args.output, args.skip_frame)例如原视频12秒，帧率50/秒。总帧为372则，实际产生图片数目为： 372 / 50 = 7张。 执行效果：
附获取视频各种参数介绍：如上面的案例cap.get(7)即获取第八个CV_CAP_PROP_FRAME_COUNT #视频总帧数 ， 以此类推。 CV_CAP_PROP_POS_MSEC Current position of the video file in milliseconds or video capture timestamp. CV_CAP_PROP_POS_FRAMES 0-based index of the frame to be decoded/captured next. CV_CAP_PROP_POS_AVI_RATIO Relative position of the video file: 0 - start of the film, 1 - end of the film. CV_CAP_PROP_FRAME_WIDTH #视频帧宽度 CV_CAP_PROP_FRAME_HEIGHT #视频帧高度 CV_CAP_PROP_FPS #视频帧速率 CV_CAP_PROP_FOURCC 4-character code of codec. CV_CAP_PROP_FRAME_COUNT #视频总帧数 CV_CAP_PROP_FORMAT Format of the Mat objects returned by retrieve() . CV_CAP_PROP_MODE Backend-specific value indicating the current capture mode. CV_CAP_PROP_BRIGHTNESS Brightness of the image (only for cameras). CV_CAP_PROP_CONTRAST Contrast of the image (only for cameras). CV_CAP_PROP_SATURATION Saturation of the image (only for cameras). CV_CAP_PROP_HUE Hue of the image (only for cameras). CV_CAP_PROP_GAIN Gain of the image (only for cameras). CV_CAP_PROP_EXPOSURE Exposure (only for cameras). CV_CAP_PROP_CONVERT_RGB Boolean flags indicating whether images should be converted to RGB. CV_CAP_PROP_WHITE_BALANCE_U The U value of the whitebalance setting (note: only supported by DC1394 v 2.x backend currently) CV_CAP_PROP_WHITE_BALANCE_V The V value of the whitebalance setting (note: only supported by DC1394 v 2.x backend currently) CV_CAP_PROP_RECTIFICATION Rectification flag for stereo cameras (note: only supported by DC1394 v 2.x backend currently) CV_CAP_PROP_ISO_SPEED The ISO speed of the camera (note: only supported by DC1394 v 2.x backend currently) CV_CAP_PROP_BUFFERSIZE Amount of frames stored in internal buffer memory (note: only supported by DC1394 v 2.x backend currently)
|
微信公众号：玩转测试开发 欢迎关注，共同进步，谢谢！【本文地址】