Why some .mp4 files running but only showing black screen?

folom

Some of the .mp4 files uploaded on the server running but only audio hearing no visual (just black screen). What would cause this? How can I fix it?
Thx

saibal

This could be the case of the missing codec.

OmgpleaseRead

@folom its a great question for the Indian tech support you are trying to hire in one of your many other threads

folom

@saibal said:
This could be the case of the missing codec.

How can i install it? on the server side or script side?
or transcoding?

mrclown

Use VLC and check media information. If codec isn't supported in your targeted browser/players, convert them to supported codec.

gol3m

If you convert the files to x264 (video) AAC (audio) with ffmpeg, it should work. However, converting reduces the quality of the video.

AC_Fan

If you are only hosting the files, codec issues will be only client side. Use VLC or MPC-BE to try and identify the issue.

wa44io4

maybe your files are not truly MP4 but just renamed to MP4 or, the type of MP4 video you have is not proper for streaming over web.