Add a scanline generator to a chienese upscaler

I have this generic upscaler that don't use enough. Recently I read an article on mmmonkey about a diy scanline generator http://www.mmmonkey.co.uk/scanlines-do-it-yourself/ . This is the crude schematic of the project

The article claims that this project is for vga scandoulbers, but I'm curious if this can work on an hdmi upscaler. If I get the RGB and vertical/horizontal sync from the scart input, and send it to vga ,will it work?

 

It would do something, but I don't think you will like the result. The original design worked like this:

Input signal (240p) -> Line Doubler (480p) -> Scanline generator (480p with half blank lines) -> Display

The net effect is that although the scanline generator is discarding half the video lines you aren't actually losing any real data since the lines it's losing were generated by the line doubler.

If you put it on the input, you get this:

Input signal (240p) -> Scanline generator (240p with half blank lines) -> Upscaler -> Display

So effectively the upscaler ends up with only 120 lines of video information to work on because the other lines have been removed.

 

Edit - Less words: Get the OSSC

 

I should have expected that. In theory, if I choose to upscale on 1080p (the scaler has this option), won't I be able to compensate some of the lost video data? Or the image has to be 480p at all cost?

I'm indeed saving up for an OSSC. I wanted to experiment with this upscaler, since I intended not using it at all due to it's poor video quality.

 

It will do something - but nothing you can do after the scanline generator can compensate for the fact there are only going to be 120 lines of actual video data because the other 120 lines have been blanked out.

 

Edit - less words - more links:
http://backtothearcade.net/2017/02/27/adding-scanline-generator/
https://paradisearcadeshop.com/scan-line-generators/1253-mini-slg.html