The VideoLAN Forums

Hi

I would like to develop a video player based on libVlc to display several videos (up to 5) with frame accurate synchronization. It is something like using the --input-slave option of the VLC command line. I do not find how to do this using the libVlc API. For example using libvlc_media_player_set_media will only allow one media to be used...
Do I need several libVLC instances ?

Are the videos the same format and same encoder?

Yes, same encoder, same encoding format, same framerate.
I'm not sure for the picture size.

VLC can theoretically do it, though the CPU and/or GPU may not be able to keep up... However, there are no provisions for more than one embedded video frame in the current LibVLC API. Patch welcome.

Thank you for your answers.

I tried just launching several media player, each with its own media. I observed lacks of synchronization after a few minutes.

So you say I need to patch libVLC to achieve synchronous reading. I'm completely new to libVLC, I use vlc-qt from Tadej Novak. I think I'm gonna have to patch it too, but this will be the easy part I guess
I think I will really need some help to get started.

I tried to find out how this is done with vlc --input-slave but I'm stuck...

5 years later... found a solution? Did you try SyncPlay ?