How do I view two videos side by side? The absolute easiest way is GridPlayer. However I liked one of the solutions that went something like this:
mpv --lavfi-complex="[vid1][vid2]hstack[vo];[aid1][aid2]amix[ao]" input1.mkv --external-file=input2.mkv
Problem is that command doesn't accept videos with different resolutions; the answer is hidden in GridPlayer which uses VLC.
This is the error that the command outputs:
C:\>mpv --lavfi-complex="[vid1][vid2]hstack[vo];[aid1][aid2]amix[ao]" m1.mp4 --external-file=m2.mp4
(+) Video --vid=1 (*) (h264 3840x2160 30.000fps)
(+) Video --vid=2 (*) 'm2.mp4' (h264 1920x1080 30.000fps) (external)
(+) Audio --aid=1 (*) (aac 2ch 44100Hz)
(+) Audio --aid=2 --alang=eng (*) 'm2.mp4' (aac 2ch 44100Hz) (external)
[ffmpeg] Parsed_hstack_0: Input 1 height 1080 does not match input 0 height 2160.
[ffmpeg] Parsed_hstack_0: Failed to configure output pad on Parsed_hstack_0
[lavfi] failed to configure the filter graph
Exiting... (Errors when loading file)
Because I was trying to play a 1080p and 4K video side by side.
How to fix the command so that it works no matter what?