Avidemux green is not like other video players

[j2l]

The original video plays a different green with VirtualDub2 or VLC, it's less yellowish in Avidemux (YUV instead of RGB?).
Actually, I'd like to keep this AviDemux green, so I tried many many combinations of settings (muxer, encoder, filters) to get it.

[Attachment 52215 - Click to enlarge]
Can't find the perfect setting,
Contrast helps, but yellow is back after saving the file.
I guess it's the U and V settings to have a green with less yellow (more blue & cyan) but I can't find the right setting.
Any idea?

[hello_hello]

I don't understand what Avidemux is doing. If you open your image above in Avidemux and compare the preview to the image, you'll see the colors are different, and how different seems to depend on the Video Display in Preferences/Display, but if you use the File/Save Image menu and save a screenshot as a bitmap, the bitmap colors match the original png, so I assume Avidemux isn't changing the colors, only displaying them incorrectly.

I'm pretty sure it's not the result of a conversion between RGB and YUV using the wrong matrix, so I'm not sure what's going on.

[j2l]

Thanks!
I tried all settings in preferences > display and greens don't change.
So, maybe it's because I'm on linux with color profile?

[Attachment 52226 - Click to enlarge]

[hello_hello]

I rarely use Avidemix myself, but it's probably nothing to do with Linux.

Here's a comparison of MPC-HC and Avidemux displaying the same YV12 video. I'm still running XP.
Green didn't change, or if it did it's hard to see, but orange, blue and yellow are different. Mental!

The third screenshot was saved via the Avidemux "File/Save Image" menu. The colors are back to normal.

[j2l]

Thanks hello_hello
Exactly, and if you try changing the display preferences, you keep the same color changes in the avidemux preview, right?

[hello_hello]

I checked each option this time, and the colors change for me. The Video Display choices (when running XP, at least) are Qt, DXVA2, OpenGL and SDL.

OpenGL, which I assume is the default, displays incorrect colors (fixable for me, see below). Qt displays the same incorrect colors as OpenGL.

DXVA2 and SDL display the colors correctly.

Under the Display tab, there's an option labelled "enable opengl support". Checking that option makes OpenGL display the correct colors for me. I've no idea why it wouldn't be checked by default.

I don't understand the sdl driver choices, but I know nothing about video drivers. For me, changing that option did nothing, as each time I restarted Avidemux the sdl driver option had reset back to "software" (I restarted after changing the Video Display option each time, to ensure the new choice was being used).

I was opening a standard YV12 video. To the left of the preview, the Video Decoder was shown as "Lavcodec RGB" when the wrong colors were being displayed. For DXVA2 it shows "Lavcodec DXVA2" and for SDL it's "Lavcodec SDL2". When "enable opengl support" is checked in preferences and opengl is selected as the Video Display, it shows "Lavcodec QtGl".

Hopefully you'll be able to get it to display the correct colors while running on Linux too.

PS. I was checking a SD video. If Avidemux always uses the same colorimetry for YUV sources regardless of resolution, which would mean HD YUV video is converted to RGB using the same formula as for SD, the colors may still look a little different in the preview. I don't know that's what happens as I haven't checked, but it's a small difference anyway. Nothing like the difference in the colors without opengl support enabled, and nothing to worry about.

[j2l]

Thanks @hello_hello,
You've tried a lot of settings to help me out.

Well, AVIDemux is weird indeed.
I just stop trying to understand and use it for what it can do: remux.