| |
pepto
Account closed
Registered: Nov 2004
Posts: 35 |
colodore is the new pepto
Hey guys, I remeasured the video-signals of my VIC-II's and slightly updated my 15 year old attempt at calculating an rgb-clone. While at it, I also measured VIC & TED and made a little website about it, that allows you to adjust brightness, contrast and saturation as you like and then save your own custom palette to a png-file.
http://www.colodore.com
I took extra care to make sure, that the brightness, contrast and saturation sliders behave the same way as my 1084s.
While closely comparing my LCD to the 1084s, I found that making the transparency of scanlines dependent on YUV's Y (so they are less visible for brighter colors) looked a lot more like the real thing. I also noticed that the phase-shift on odd-lines happens for YUV's V only and there's even a name for it in video-lingua: hanover bars.
After implementing this, I'm happy to say that the images on my LCD and 1084s are remarkably close.
I will write a more detailed article about it in January, but seriously need a christmas-break first...
Cheers,
pepto |
|
... 97 posts hidden. Click here to view all posts....
|
| |
soci
Registered: Sep 2003
Posts: 473 |
Just a few more steps and there will be separate RGB sliders for each colour for maximum flexibility ;) |
| |
chatGPZ
Registered: Dec 2001
Posts: 11120 |
i'd be most interested in seeing the algorithm applied to NTSC (using the sony decoder matrix).....
did a quick test in VICE with the hannover bars stuff as you implemented them.... now everything is pink. knoekicolors =) i think the renderer cant be reused as is and must be rewritten. sux ;_; |
| |
pepto
Account closed
Registered: Nov 2004
Posts: 35 |
Quoting Groepazi'd be most interested in seeing the algorithm applied to NTSC (using the sony decoder matrix).....
If I didn't f*ck it up, like this I guess (only tested in Chrome): http://www.pepto.de/groepaz.html |
| |
chatGPZ
Registered: Dec 2001
Posts: 11120 |
hard to tell (for me anyway) without a test picture and CRT emulation attached.... but thanks :) (incase you want to add some pictures for ntsc, check the work of DocJM - awesome stuff. and pics like this can tell you if you got the aspect ratio right :)
oh and i almost forgot, i have a feature request.... could you add an option to download the palette in VICE format? converting them by hand is a bit annoying =) |
| |
ilesj
Registered: Jun 2012
Posts: 27 |
Btw why the delay line doesn't seem to have any effect on the hanover bars? |
| |
pepto
Account closed
Registered: Nov 2004
Posts: 35 |
Quote: Btw why the delay line doesn't seem to have any effect on the hanover bars?
Good question, I'm wondering this myself... looking at the output though, both effects are definitely present. Chroma blending with the previous line, and phase-shift for the v-component. |
| |
chatGPZ
Registered: Dec 2001
Posts: 11120 |
oh it doesnt? i guess thats the problem with the vice renderer. are you sure it actually doesnt? does joes "play with colors" work correctly with your stuff? |
| |
pepto
Account closed
Registered: Nov 2004
Posts: 35 |
Quote: oh it doesnt? i guess thats the problem with the vice renderer. are you sure it actually doesnt? does joes "play with colors" work correctly with your stuff?
How do I know if it works? I'm actually cooking dinner right now, but I will look into this later... ;-) |
| |
chatGPZ
Registered: Dec 2001
Posts: 11120 |
Play With Colors 2 should look like this |
| |
pepto
Account closed
Registered: Nov 2004
Posts: 35 |
Quoting Groepazdoes joes "play with colors" work correctly with your stuff?
This is really interesting! I didn't know about this test before.
I would say 90% of the fields look correct (I'm comparing colodore to the real C64 on the 1084s) and this is because of delayline-style chroma-blending.
A few adjacent fields however, which only differ by one color being on even lines in one field and on odd lines in the other, blend differently on the 1084s compared to colodore.
Which means the color-generation described on http://www.pepto.de/projects/colorvic/ works just fine and also the delay-line on colodore, but the way I do hanover bars doesn't seem to work 100% yet, even though it looks like a perfect match on solid colored fields, so it definitely is the phase-shift on v, just like it should be.
I'm puzzled for the moment and need to get some sleep.
At which point do you guys inject hanover-bars into the signal in Vice? I do it after the delayline, that's why a field with (lgrn/yel) looks the same as (yel/lgrn) before the hanover bars are added. |
| Previous - 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 - Next |
