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Addison
04-03-2009, 07:19 AM
Hey all.

I've rifled the net and can't seem to find even a single post on getting the best video settings for Xbox's v.13 of Dosbox.

Could someone point me to a web page or perhaps give me the proper width and height values for both a 4:3 and widescreen TV?

640x480 is much too big for my 4:3 32" TV and 320x240 is much too small. Any other values in between these and I'm having the hardest time reading the text.

This is one of my favorite posts:
Fancy Xbox (http://fancyxbox.info/?doc=1&secao=screen)

Sure would love it if I could find something similar to this for DosXbox's settings.

Anyone here have Dosbox running on their living room TV?

Thanks ahead!

AlumiuN
04-03-2009, 07:47 AM
Isn't 640x480 the native NTSC resolution?

Addison
04-03-2009, 08:52 AM
Isn't 640x480 the native NTSC resolution?

I'm not sure, AlumiuN.

I just know that 640 clips huge chunks off the left and right side of the screen.

I'm not using any scalers and it's a Sony Trinitron 32" screen.

I have to be missing something on this but I can't find anyone that has posted on this before.

I've got the entire night off tomorrow and was hoping to play some "Eric the Unready" piped through some beefy speakers.

Hopefully someone can give me a quick fix before tonight.

Cheers! :)

Addison
04-03-2009, 09:50 AM
Could it have something to do with the fact that the TV is probably 15 years old?

I'm having a hard time trying to find out it's pixel resolution while searching online.

Japo
04-03-2009, 07:31 PM
It's just like any other screen. You must know where you stand, figure out what resolution does it use, and considering the resolution of the game(s) you want to run, consider if you can make it fit with just scaling, or you have to resort to aspect correction. Whatever, you should set the fullresolution variable in dosbox.conf to the resolution of the TV set, otherwise it will be the TV set who'll make an aspect correction, and you don't want that--you've already seen the result.

AlumiuN
04-03-2009, 08:58 PM
Try using aspect correction.

Addison
04-03-2009, 09:10 PM
Thanks a bunch for the reply, Japofran!

My Sony Trinitron's TV model number, not that it really matters, is KV-32S20.

I talked with customer service and they told me that it has a pixel dimension of 768x480.

The few games I have that I would like to play on the TV all have a needed resolution of 640x480. So one would think that it would easily fit within that dimension.

However, there's no such thing as the fullscreen resolution variable you would normally find in a dosbox.conf file.

Instead, it asks me for the maximumX and MaximumY values while setting the game screen size/position.

So I don't understand why setting MaxX=640 for width creates so much overscan. And to be honest, I'm getting some good overscan as well setting MaxY=480.

I'm just trying to do a perfect 2x resolution so I'm really not getting this.

Now I'm lost here. Crap. :(


I'm going to look at it some more right now and post back on some of the options it gives me in the menu settings.

Addison
04-03-2009, 09:53 PM
Okay, AlumiuN got it right!


By pressing Start on the controller, when changing the game screen size/position, you can toggle aspect correction between none, default, and TV.

Awesome guys!


Thank you so much!

Japo
04-03-2009, 10:32 PM
DOSBox can also do the aspect correction, using your graphics card, so maybe you'll get better quality. For this set "fullresolution=768x480" the same, and now also "aspect=true". Anyway aspect correction always makes you lose definition.

I didn't mean you change the TV set resolution, I'm assuming you're stuck with that. I suppose that if you computer sends your TV set an 768x480 image, you should get good definition (?) without further aspect correction. For example I know my newest TV set supports at least 800x600, I can use it as computer screen, and I get perfect definition if I use 800x600, but if I use another I get crappy definition due to aspect correction and aliasing.

I mean you edit dosbox.conf and set "fullresolution=768x480". I don't know if it will work, perhaps your computer's graphic card can't output that resolution even if it's the only one your TV set can input... But try it. However I don't know specifically how those old TV sets work.

DOS games usually have either 320x200, or 640x400, or 640x480 pixels. If you manage to make your card output 768x480, and your TV set doesn't add noise (I can't help you with that, other than recommending to use the precise resolution it supports), you should get good images.

With default scaler settings, DOSBox will resize the game's image if necessary, following integer ratios only and the same one for height and width (keeping aspect), until it fits as much of "fullresolution" as possible. The rest of the "fullresolution" will be filled with a black frame.

For example I've tried setting fullresolution=768x480 in my DOSBox. DOSBox does output an image with that size, but either my graphic card or my screen, none of which support that resolution of course, falls back to the closest supported one, 800x600, but they're not so kind as DOSBox to center the image. You can see the result here:

http://s102.photobucket.com/albums/m87/japofran/tutorial/th_dosbox32.png
(click to enlarge) (http://i102.photobucket.com/albums/m87/japofran/tutorial/dosbox32.png)

If you think how the image is handled at each step, it's pretty straight forward what will happen. However in your cause I don't really know what your TV set may do on top of all this.

Addison
08-03-2009, 02:18 AM
Thank you for the excellent reply, Japofran!

Yeah, the thing with the DosXbox version is that there is no dosbox.conf file.

If it was just about editing that file, I totally would be on top of this.

However, I think I'm only left with stretching and changing the screen size until it "appears" to be correct. That's why I can't seem to get a perfect pixel resolution.

It would be nice to be able to enter in the dimensions but I don't think that feature is available.

I have the whole weekend to try and get it down right so I'll see what happens from there.

If not, the wife already said I can buy a new HD TV since the one in our living room a is real piece anyway.

Cheers!

AlumiuN
08-03-2009, 02:26 AM
If not, the wife already said I can buy a new HD TV since the one in our living room a is real piece anyway.

Why bother fixing it manually then? :D

Addison
08-03-2009, 08:34 AM
one in our living room a is real piece anyway.First off, I'm sorry for my decrepit language... Darn it, I need to learn me English! :doh:

Anyway, I'm heading off to Best Buy to pick up a HD TV tomorrow, that is, if I can wake up before 7:00 pm... I really should lay of the excessive alcohol. *lol*

So will I get better results with a newer TV?

From my understanding, old TV's took an image it receives and then projects that display as best as it can on the screen, there's not really a pixel count one might think such as using a monitor. However, with a HD TV, I can actually count the pixels to get a perfect resolution.

Yeah, or am I still missing something on this?

Japo
08-03-2009, 09:06 PM
Yeah, the thing with the DosXbox version is that there is no dosbox.conf file.

Why? Anyway you can download it and install anew from www.dosbox.com. Or you can type this into DOSBox's command line to create a new dosbox.conf:

config -writeconf dosbox.conf

Maybe moderndigital TVs are more standard, but I suppose in the end it's more or less the same. A TV set will have a resolution (yes old analog ones do have a pixel count), or a set of resolutions. Either you go for stretching the image, and you get a full screen image easily but somewhat distorted; or you look for the resolution that will fit the game image best, with just scaling and no aspect correction.

Addison
09-03-2009, 08:05 AM
Hey there again, Japofran.

I think you missed a small part of my previous posts.

I'm running DosXbox, it's a build for the original Xbox machine, and while it's very user friendly, it seems to be quite difficult by way if you want specific, pixel perfected dimensions when running a game.

And yeah, there's no dosbox.conf file to mess around with, just some stripped down menus and options for it.

I was hoping if there was anyone here that had the same version on their Xbox or perhaps another build for any of the other various home consoles and what type of settings they use to generate a correct display on their TV sets instead of using a typical computer monitor.

Nuts, I think I just lost you even more on this.

Japo
09-03-2009, 10:15 PM
Ah sorry I missed the extra X. :P

You may be able to guess the resolution that DOSXBox uses, if you can take a screenshot and inspect its resolution (pixel count) DOSBox saves screenshots as they are served by DOS, not as they are finally displayed, nor even as they are scaled into fullresolution. They always represent the original image before any manipulation.

But if you can't configure DOSXBox's resolution, I guess you're stuck with changing the on in the TV set if you're lucky, or just go for stretching even if the image is distorted. I suppose you can find support about DOSXBox somewhere on the Internet.