Python OpenCV video format play in browser
Get .webm suffix audio file.
fourcc = cv2.VideoWriter_fourcc(*'vp80')
video_writer = cv2.VideoWriter('file.webm', fourcc, 20, (640, 480))
In html:
<body>
<video width="320" height="240" controls>
<source src="file.webm" type="video/webm">
</video>
</body>
It works on centos7 and Windows10.
MP4V or MPEG-4 part 2 is not supported by most browsers, you may want to try H.264 (MPEG-4 part 10) instead.
To do that, change:
fourcc = cv2.VideoWriter_fourcc(*'MP4V')
to
fourcc = cv2.VideoWriter_fourcc(*'H264')
If you are using Python 3, use the following hexadecimal code instead (there seems to be a bug when using the four bytes notation):
fourcc = 0x00000021
Run the script and you will likely get the following error message:
Failed to load OpenH264 library: openh264-1.6.0-win32msvc.dll Please check environment and/or download library: https://github.com/cisco/openh264/releases
You need to do as the message says and download the required library from github and place it somewhere accessible by your PATH.
Using H.264 compression you will also get a smaller file which is better for Web.
I know the question is old but for everyone that is looking for a compatible codec + container for web browser : VP8 or VP80 is a compatible encoder
cv2.VideoWriter_fourcc('V','P','8','0')
I used it with .webM as a container.
Native WebM support by Mozilla Firefox,[7][8] Opera,[9][10] and Google Chrome[11] was announced at the 2010 Google I/O conference
https://en.wikipedia.org/wiki/WebM
it worked like a charm and with pretty good performance even though for some reason I got this error when creating videoWriter objects :
OpenCV: FFMPEG: tag 0x30385056/'VP80' is not supported with codec id 139 and format 'webm / WebM'