SD video becomes dull when upscaling to HD

[Alwyn]

Install the Colormill plugin for VDub and use the Levels sliders (lows/mids/highs). Works well.

Get Colormill from here:

https://github.com/Bassquake/ColorMill

Drop the VDF into the appropriate 32bit or 64bit Plugins folder.

[jagabo]

the white shirts are blown out

Isn't there a filter to consider only the whites and grey them out a bit in Avisynth?

AviSynth has a Levels() filter:

http://avisynth.nl/index.php/Levels

Tweak(), SmoothTweak(), and ColorYUV() use the terms contrast and brightness but the really mean gain (multiply) and offset (add).

For example SmoothTweak(contrast=0.9) will mulitiply all Y values by 0.9. 16 will become 14 (rounded down from 16*0.9=14.4), 235 will become 212 (rounded up from 235*0.9=211.5). So the black level will come down a little bit, and the white level will come down a lot. If you don't want that small drop in black level you can add the brightness option to bring everything up by 2 or so; 16 will remain 16 (14+2), 235 will drop to 214 (212+2).

The problem with your video is that the brights are already blown out. You can lower them even more but there will still be no detail in them. You'll just be left with a duller looking picture.

[Selur]

One cloud use some luma limit masking to only change the gamma of the whites,... (https://pastebin.com/0JeCXENq)
But yeah, not much one can do,..
https://imgsli.com/MzEyMjY3