Any Fix For The Tv-out Scaling Artifacts?


kouky

kouky

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Website
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The GP2X offers a crappy TV-out, especially in PAL.

I haven't followed the scene for quite a while now...
Did some dev found a workaround or a way to fix those scaling artifacts?

I wish the next version of my project Pikix (http://www.pikilipita.com/vj/pikix) could include a fix for the TV-out!

Kind regards

P
 
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rlyeh has done some work on this but never released:

CODE

http://www.gp32x.de/board/index.php?showtopic=38013



Edit: oh I see you posted to that very thread, so you already know this.
 
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'notaz' said:
rlyeh has done some work on this but never released:

CODE

http://www.gp32x.de/board/index.php?showtopic=38013
Click to expand...
Edit: oh I see you posted to that very thread, so you already know this.

It is a shame, because the results were looking very promising.
 
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i left a comment on his website regarding this

CODE
http://www.retrodev.info


crossing my fingers :)
 
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It looks like I might have another month of time to code that I didn't think I had.

I will get in touch with Rlyeh so I can include this fix in Open2X. In the mean-time I will build an Svideo->composite adapter so I can test it.
 
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'Senor Quack' said:
It looks like I might have another month of time to code that I didn't think I had.

I will get in touch with Rlyeh so I can include this fix in Open2X. In the mean-time I will build an Svideo->composite adapter so I can test it.
Click to expand...
Fantastic news Mr SQ :)
 
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'Senor Quack' said:
It looks like I might have another month of time to code that I didn't think I had.

I will get in touch with Rlyeh so I can include this fix in Open2X. In the mean-time I will build an Svideo->composite adapter so I can test it.
Click to expand...
The last month I spend only in the Pandora part of the forums, so i am not uptodate.
But about a year ago open2x was "short before a release" I waited and waited and nothing came out :(
My question now, have I missed the release?
 
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'Creature XL' said:
'Senor Quack' said:
It looks like I might have another month of time to code that I didn't think I had.

I will get in touch with Rlyeh so I can include this fix in Open2X. In the mean-time I will build an Svideo->composite adapter so I can test it.
Click to expand...
The last month I spend only in the Pandora part of the forums, so i am not uptodate.
But about a year ago open2x was "short before a release" I waited and waited and nothing came out :(
My question now, have I missed the release?



No, we only had a DR4 release. The reason it has taken so long is that there's only a few people working on it and of those people, only 1 or 2 are really active at any given point in time. The good news is that my employer has only given me work for half this month (because of the economy) so I will have time to finish Open2X. Bad news is I don't get paid :(

Other good news is that the place I am living temporarily has a TV with SVideo input, so I spent all last night working on TV Out and will continue to do so until I can hopefully make some progress.
Click to expand...
 
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I have successfully perfected TV out for apps on the GP2X, thanks to some help from Rlyeh's source code and a lot of experimentation of my own.. You can see from my post on the third page of this thread:

http://www.gp32x.de/board/index.php?showt...45518&st=80

QUOTE

TV Tweaking Daemon:
Frustrated that the GP2X's TV output often leaves the image hanging off the bottom and side of the screen? Well, I have fixed this for 90% of GP2X applications. I altered the tv chip's linux driver to allow a separate backdoor daemon to tweak the image while programs run. I added new per-application settings into GMenu2X to allow adjustment of the X and Y TV image offsets, as well as adjustment of the X-axis and Y-axis scaling (12%-200%). You can tell the daemon to tweak continuously every x seconds or you can tell it to just tweak once and then terminate.

The only applications this doesn't work on are some SDL apps that used Paeryn's library together with double buffering. The reason this doesn't work is because Paeryn's library resets the scaling registers with every buffer flip and there's no way to compensate for this. Some of my ports are affected by this (Tileworld2X, Koules2X), and some aren't. I will be releasing an updated version of SDL that fixes this behavior, and also hopefully releasing updated versions of my ports that use this newer SDL. Most SDL applications do work, however. Any that used Rlyeh's minlib are guaranteed to work, things like Picodrive, for instance, greatly benefit..
 
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'kouky' said:
Nice,

does-it get rid of the scaling artifacts ?

How can I implement thast fix into my application ?
Click to expand...
Yes, it allows you to set the scaling to 100% and still have almost all of the available image on the screen. Because of TV overscan, however, most analog TVs (maybe digital) will still have sections around the edges they can't display.. that is normal. Only when you reduce the scaling percentage below 100% will you start to notice the scaling artifacts start to come back, as the scaling chip doesn't do interpolation, it just drops entire rows of pixels. Using my TV daemon in Open2X, you can center the screen to make sure the overscan is uniform around the edges.

There's no need to integrate this into your application, it's all handled automatically in the background in Open2X. In fact, hitting the scaling registers in your application will mess up Open2X's TV daemon and force the user to disable it, and for no good reason.

One thing you can do to make sure your application is compatible with the daemon is to use the latest Open2X SDL library. Unfortunately, I haven't compiled and packaged it up yet :) Forgot to, but I will bring it to the library here on my next visit, maybe a week or two max.
 
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Thank you Senor,

But I meant:
Can I add that fix to my application so every user, including non open2x ones (as me!) will have a clean TV-out?
 
'kouky' said:
Thank you Senor,

But I meant:
Can I add that fix to my application so every user, including non open2x ones (as me!) will have a clean TV-out?
Click to expand...
You will be able to download the source code off Open2X's SVN server once I get some real internet and commit the source. You could add an option to launch a private version of the daemon yourself (just be sure to kill it after you exit).
 
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Thanks! Now I can finally finish my 5" GP2X project. Shitty TV out was what was holding me back. :D
 
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Public DR6 beta
CODE
http://www.gp32x.de/board/index.php?showtopic=47228
 
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