Reason: mp4 seems to be a patented audio and video format. node-webkit doesn't support it... it seems. .
Solution:
Install the chrome browser locally, go to the installation directory (for example: c: GoogleChromeApplication37.0.2062.103), and find the ffmpegsumo.dll file.
Copy (ffmpegsumo.dll) and replace ffmpegsumo.dll in the node-webkit directory.
Note: Since there are many chromium versions, the chromium version of the downloaded chrome browser must be consistent with the chromium version of node-webkit. Otherwise, copying the ffmpegsumo.dll file will be useless. It can also cause software to crash.
Where can I see the version number? As follows:
Linux: 32bit / 64bit
Windows: win32
Mac 10.7: 32bit / 64bit
(The chromium version of node-webkit-v0.10.0-win-ia32 is also 35)
File: ffmpegsumo.dl download address (windows32/64) http://pan.baidu.com/s/1wBItK
Personally tested winxp ~ win8, 32/64 available.
The above is all the content described in this article. I hope it will be helpful to everyone learning node.js.