.avs shows fine but ffmpeg creates black video

I'm not sure what I'm doing wrong. I have an .avs file: Code:

Maybe try variations of below to figure out problem. [1st step is to find out if problem is in your script, or ffmpeg command (or both)] Code:

I kinda suspect that problem might be your ffmpeg.exe, here:- the one I'm using (I think maybe by PatMan), supports avs input, perhaps yours dont properley support it. Maybe not the most recent version, but not so old (maybe about XMas issue). Is static linked, ie no dll files needed.

I downloaded that ffmpeg and got the message that I'm using a 64 bit Avisynth... Took a look and I was using Avisynth+ on this machine. So I uninstalled that and found I had 2.58, 2.60, and Plus. Not sure what I should be running but installed 2.60 and tried. Playing the .avs by double-clicking still worked but this time using: Code:

Yes, I have 7zip and used its ffmpeg.exe for my test. That's the one that gave the error... but now it's using the Avisynth 6.0 which is 32 bit. Were you able to use the file and avisynth code I referenced with any success?

With same ffmpeg and same avs+ x64, script [I changed to LSmash, DirectShowSource is infamous for its being not frame accurate,and output was a bit choppy] Code:

And output from DebugView when encoding in ffmpeg Code:

Potplayer OK, VLC OK, MPC-HC (open OK from within MPC-HC via file menu), Windows Explorer right click open in MPC-HC does nothing. Windows Media Player, shows Black Screen, same as your original problem. Avoid RGB with Alpha Channel, ie use YV12 [Return ConvertToYV12() at end of script ] EDIT: Ignore the MPC-HC problem, It dont open other files either, I must have a problem there. EDIT: Damn, about 5->10 mintues after trying to open another mp4 in MPC-HC via Explorer right click, it jumped up and started to play, perhaps Antivirus was scanning entire mp4 file or something. EDIT: From the ffmpeg text output [looks like its any RGB within an Mp4 (and not just alpha) that is the problem for Windows MediaPlayer] Code:

Well... thanks a ton for all that. I'm going to reinstall Avisynth+ and try again. The video player is just Windows Media Player. I'll let you know how it goes.

Yep, dont use Windows Media Player (that IS the problem), and avoid rgb in mp4, use YV12.