Update question:

After testing, neither flash nor video tags can play mp4 files encoded in MPEG4. Now I want to change my thinking and want to prohibit users from uploading videos in this format from the source. I would like to ask if this encoding format can be recognized when uploading MP4 files on the web page? ?

The project I am developing plays videos uploaded by others. I encountered an MP4 file recorded by a mobile phone. When using the video tag to play, there is only sound but no picture. I originally thought that using flash could solve the problem, but then using jwplayer and ckplayer became a tragedy. There is only sound but no picture. I would like anyone in the forum who knows about this to help me find out how to solve it. I hope you can help me test it. Thank you!

Video information:

Video address:

http://test1-store.oss-cn-beijing.aliyuncs.com/591abafc12bbb0e42cc3896a.mp4

Use jwplayer to play the picture: