请解释一下这段代码 #输出格式 if codec == "mp4": fourcc = cv2.VideoWriter_fourcc('a','v','c','1')#视频编码:h264,只有h264格式的mp4文件才能在浏览器直接播放 video_save_path = os.path.join(outputPath,"output.mp4")#创建输出视频路径 elif codec == "avi": fourcc = cv2.VideoWriter_fourcc('h','2','6','4')#视频编码:h264,只能保存为avi格式且不能在浏览器直接播放 video_save_path = os.path.join(outputPath,"output.avi")#创建输出视频路径 elif codec == "mkv": fourcc = cv2.VideoWriter_fourcc('X','V','I','D')#视频编码:XVID,此编码不需要openh264-1.8.0-win64.dll video_save_path = os.path.join(outputPath,"output.mkv")#创建输出视频路径 output_viedo.open(video_save_path , fourcc, fps, size, True)
时间: 2023-06-24 15:03:24 浏览: 81
这段代码是用来将一系列图片帧合成为视频的代码。代码中首先根据选择的编码格式(mp4、avi或mkv)选择对应的视频编码和输出视频路径。然后通过 `cv2.VideoWriter` 方法创建一个 `output_video` 对象,该对象可以将一系列图片帧合成为视频,并且指定了输出视频的格式、帧率、大小和是否为彩色视频等属性。最后,通过 `open()` 方法打开输出视频文件,准备写入图片帧。其中,`fourcc` 是视频编码格式,`fps` 是视频帧率,`size` 是视频帧大小,`True` 表示彩色视频。
相关问题
cv2.VideoWriter_fourcc()支持MP4格式的参数
cv2.VideoWriter_fourcc()支持MP4格式的参数包括:
- MP4V:MPEG-4 Part 2 video codec
- X264:H.264/MPEG-4 AVC video codec
- XVID:MPEG-4 Part 2 video codec
- AVC1:Advanced Video Coding (H.264) video codec
示例代码:
```python
import cv2
# 设置输出视频文件名、编码器、帧率、分辨率
out = cv2.VideoWriter('output.mp4', cv2.VideoWriter_fourcc(*'MP4V'), 25, (640, 480))
# 读取输入视频文件
cap = cv2.VideoCapture('input.avi')
while cap.isOpened():
ret, frame = cap.read()
if ret:
# 处理每一帧图像
frame = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
# 写入输出视频文件
out.write(frame)
# 显示处理后的图像
cv2.imshow('frame', frame)
if cv2.waitKey(1) & 0xFF == ord('q'):
break
else:
break
cap.release()
out.release()
cv2.destroyAllWindows()
```
fourcc = cv2.VideoWriter_fourcc(*'XVID') out = cv2.VideoWriter('output.avi',fourcc, 20.0, (640,480))
This code sets up a VideoWriter object to write video frames to a file named "output.avi" with the XVID codec, a frame rate of 20 frames per second, and a resolution of 640x480 pixels. The asterisk before 'XVID' is used to unpack the string into individual characters, as expected by the VideoWriter_fourcc function.