#2286 - Link - Sat Feb 01, 2003 12:01 pm
Or i can do without them?
#2287 - Splam - Sat Feb 01, 2003 12:47 pm
I could do without this...
#2289 - JonH - Sat Feb 01, 2003 2:38 pm
Personally, I think you would be better off trying to learn and read about GBA programming before you ask questions about it - since all your posts seem to be rather trivial.
Go to this site, and don't come back here until you've read it all and tried all the examples:
http://www.mdh165.pwp.blueyonder.co.uk/docstuts/docstuts.htm
;)
#2294 - Link - Sat Feb 01, 2003 2:55 pm
| JonH wrote: |
Personally, I think you would be better off trying to learn and read about GBA programming before you ask questions about it - since all your posts seem to be rather trivial.
Go to this site, and don't come back here until you've read it all and tried all the examples:
http://www.mdh165.pwp.blueyonder.co.uk/docstuts/docstuts.htm
;) |
Why now are you my Friend? :)
#2298 - Sweex - Sat Feb 01, 2003 4:54 pm
Agree with JonH. Link, read some docs!
#2306 - Maddox - Sat Feb 01, 2003 9:55 pm
Link isn't the only kindergardener posting crap questions on this forum. Every single poster should research stuff on their own and come here when they're stuck. The forums should be educational on some level, but discussion oriented as well. I must say asking if you need palettes is pretty bottom-of-the-barrel dumb.
_________________
You probably suck. I hope you're is not a game programmer.
#2549 - mo - Thu Feb 06, 2003 7:06 am
you can just as easily ignore his posts.
yes you do need a palette, otherwise everything your draw will be black (0).
#3200 - mantrid - Wed Feb 19, 2003 9:43 pm
Link, Palettes are fundamental to many graphics systems. PC's *TV's Gameboys, Aple Macs all have some sort of palette support, if you look on the web you will see how to use them and what they are for.
On the Gameboy you only need to set up a palette if you use mode 4. I think that is the only screen mode you need to set up a pallete for. The other modes you write to the screen RGB values, or Tile indices.
Palettes were probably originaly invented becuase memory was expensive, and a palettized sceen buffer reduced cost. We still have palettes today probably for a similar reason. You can do a few neat tricks with palettes too like palette animation, and Alpha blending by palette reduction(but you won't want to do that on the gba, it's got some sort of alpha blending).
* - High end TV's perhaps not the older ones. For example the Viper chip from Phillips has two cores, one MIPS and one Trimedia. The Trimedia core supports the notion of palletes, which can be used for drawing subtiles mainly, since they send palettes as part of the digital transport stream.
#3205 - CoolMan - Thu Feb 20, 2003 3:44 am
Most PC graphics hardware (nowadays) is running at (at least) 16 bpp, which is NOT a palette mode. I can't speak for macs.
As for TVs... I know that all analog television standards (NTSC, PAL) are NOT palette based. I suppose that some digital television protocols/interfaces (Which, by the way, I know nothing about) COULD be palette based, but with the number of colors that need to be availible, a palette would become extremely unwieldy, and would contradict the concept of stream. (If it was palette based, you would need to send a palette for every single frame.) Besides that, I know that many digital video (film quality) standards, such as DVD and DiVX, use 24 bpp (RGB, not palette)...
Of course, the TV could be communicating to itself in 8bpp palette based... In which case, I'm gonna wait a lot longer to get a digital TV.
[Long rant to get a single point out...]
Palette based systems are very memory efficient, but only in low (graphics) quality situations, which simply means that palettes are on their way out. As the demand for quality goes through the roof, palettes (and VRAM restrictions) go in the trash. (For instance, no self-respecting 3D engine uses textures under 24 bpp. Even if the target (render) image quality is lower, the higher quality texture map leads to better final images.)
_________________
Moron! You don't herd chickens with a shotgun!
--CoolMan
#3214 - mantrid - Thu Feb 20, 2003 10:32 am
Yes it's true that most displays use RGB based palettes. I know that subtitle information contains a palette becuase I am writing software for digital TV at the moment. Also, PC's graphics cards today still support a hardware palette.
| Quote: |
[Long rant to get a single point out...]
|
Well now we know some of the reasons why we've got palettes, which might be useful information or at least it's interesting to know, isn't it?
#3215 - FluBBa - Thu Feb 20, 2003 11:01 am
| CoolMan wrote: |
I know that many digital video (film quality) standards, such as DVD and DiVX, use 24 bpp (RGB, not palette)...
|
Well they don't use palette neither RGB, it's called YPbPr/YCbCr and is Luminance(Light) & difference for Red & Blue. and often you have the Red & Blue in a much lower resolution then the Luminance, eg 4:2:2 or 4:1:1.
_________________
I probably suck, my not is a programmer.
#3216 - mantrid - Thu Feb 20, 2003 11:32 am
Maybe I made this thread go off topic :-|. Yes, you get the luminance and chrominace in video, subtitles and other stuff - but that's not really important is it. Anyway in this TV the video buffer is RGB and the palette is RGB encoded too. The subtitle palettes are luminance and colour difference encoded so we have to convert them to RGB.
The subtitling in a digital tv broacasts uses palettes because it:
saves memory
it saves bandwith
it reduces processing time
So there is quite a good reason to have a palette. I think it all comes down to hardware cost(and perhaps the state of the art)
So my point is you still see a lot of palette type things going on in real world applications today.
I'll should stop now. I made the thread drift off topic. Sorry.
#3225 - CoolMan - Thu Feb 20, 2003 5:50 pm
| FluBBa wrote: |
| CoolMan wrote: | I know that many digital video (film quality) standards, such as DVD and DiVX, use 24 bpp (RGB, not palette)...
|
Well they don't use palette neither RGB, it's called YPbPr/YCbCr and is Luminance(Light) & difference for Red & Blue. and often you have the Red & Blue in a much lower resolution then the Luminance, eg 4:2:2 or 4:1:1. |
Ah, this explains alot, but I was refering to the way the information is stored. (like, on the disk itself...)
_________________
Moron! You don't herd chickens with a shotgun!
--CoolMan
#3228 - Lord Graga - Thu Feb 20, 2003 6:13 pm
Ok, link...I'm getting tired of your lame questions, try to figure out what you ask....
Example:
Question: Do i need palettes!
Answer:
Only 1 mode does not use palettes (mode3). This means that only 20% off all the modes actualy is useable to that "request".
Now let's see what mode 3 can do:
Plot a 32bit colored pixel.
No double buffering
Not too fast.
Is that enough?
If (youranswer=="yes")
{
SET_MODE(MODE_3|BG2_ENABLE);
}
else
{
SET_MODE(MODE_4|BG2_ENABLE);
for(i=0;i<256;i++) PaletteMem[i] = Palette[i];
}
#3264 - FluBBa - Fri Feb 21, 2003 10:47 am
| CoolMan wrote: |
| Ah, this explains alot, but I was refering to the way the information is stored. (like, on the disk itself...) |
It is stored in YPbPr on disc and only converted to RGB if you play it on a PC with a sucky gfxcard, new gfxcard can handle YPbPr natively.
_________________
I probably suck, my not is a programmer.
#3266 - ampz - Fri Feb 21, 2003 12:15 pm
| FluBBa wrote: |
| CoolMan wrote: | | Ah, this explains alot, but I was refering to the way the information is stored. (like, on the disk itself...) |
It is stored in YPbPr on disc and only converted to RGB if you play it on a PC with a sucky gfxcard, new gfxcard can handle YPbPr natively. |
And in that case the conversion is done by the gfx-card instead.
You see, it must allways be converted to RGB, even in a TV.
#3276 - CoolMan - Fri Feb 21, 2003 5:23 pm
| FluBBa wrote: |
| CoolMan wrote: | | Ah, this explains alot, but I was refering to the way the information is stored. (like, on the disk itself...) |
It is stored in YPbPr on disc and only converted to RGB if you play it on a PC with a sucky gfxcard, new gfxcard can handle YPbPr natively. |
Uhh, I thought that MPEG2 only supported RGB. As a matter of fact, I woulda sworn it. The magical VOB files (that you find on a DVD) are really just simple wrappers which are capeable of stream encoding + padding the data for random access.
Besides, whats so 'sucky' about RGB? It is very simple on all sides, and can achive infinite colors just by increasing the (analog) bandwidth, and (digital) bits per pixel.
The only reason why RGB doesn't look better (IMHO) is because we are still stuck on old analog formats (NTSC (or PAL)) except for these wierd formats where they break out the signal differantly. I prepose a simple standard that is basically a high-speed, serial (maybe optical?), interface which would make several improvements on NTSC or other analog counter-parts. (BPP, Pixels-per-scanline, scanlines-per-frame, and maybe even more FPS.)
This wouldn't really be useful for broadcast, cable or satelite or whatever, but it would be good to communicate between PCs and monitors, and it would be good to communicate between DVD players and TVs, and it just might turn out to be the standard that theatres use for displaying digital movies. (Have you ever sat through a digital video stream at a theatre? the resolution is AWFUL!)
Just some thoughts based on observation and reasearch.
_________________
Moron! You don't herd chickens with a shotgun!
--CoolMan
#3303 - FluBBa - Sat Feb 22, 2003 1:18 pm
| CoolMan wrote: |
| FluBBa wrote: | | CoolMan wrote: | | Ah, this explains alot, but I was refering to the way the information is stored. (like, on the disk itself...) |
It is stored in YPbPr on disc and only converted to RGB if you play it on a PC with a sucky gfxcard, new gfxcard can handle YPbPr natively. |
Uhh, I thought that MPEG2 only supported RGB. As a matter of fact, I woulda sworn it. The magical VOB files (that you find on a DVD) are really just simple wrappers which are capeable of stream encoding + padding the data for random access.
Besides, whats so 'sucky' about RGB?
|
I was refering to the gfxcards not RGB, old (sucky) cards doesn't have YPbPr overlay support, this saves bandwith to the GFX card and CPU, the signal to your monitor is still RGB.
You mean that mpeg2 is uncompressed or ?
Have you made backups of your DVD movies? Then you probably have seen that it saves the images in some format like TGA or BMP, and then you say that it's RGB in the VOB file right?
Not so, as there are few supported file formats which support some kind of YPbPr, so the ripping program have to convert the images before saving. New versions of videoediting programs can uncompress->compress without going via RGB.
Yes I agree that both PAL & NTSC are bad.
Have you heard of HDTV?
_________________
I probably suck, my not is a programmer.
#3304 - Daikath - Sat Feb 22, 2003 2:38 pm
Mpeg is also compressed, prehistoric avi is the only videoformat that is uncompressed RGB, but they use lots of codecs for that also now.
_________________
?There are no stupid questions but there are a LOT of inquisitive idiots.?
#3311 - ampz - Sat Feb 22, 2003 5:38 pm
| Daikath wrote: |
| Mpeg is also compressed, prehistoric avi is the only videoformat that is uncompressed RGB, but they use lots of codecs for that also now. |
DVD==mpeg(2)
#3312 - Daikath - Sat Feb 22, 2003 5:49 pm
Yes, but that isn't uncompressed.
_________________
?There are no stupid questions but there are a LOT of inquisitive idiots.?
#3371 - CoolMan - Sun Feb 23, 2003 6:46 pm
I may be wrong, but I was under the impression that the MPEG2 (read: VOB) on a dvd stored the pixels in RGB format, since I wasn't aware of any MPEG2 standard that allowed for anything other then RGB.
As for AVIs, AVI doesn't mean uncompressed. AVI is a simple file format which allows two paralell data streams to exist in the same file. (AVI == Audio Video Interleaved) AVI couldn't care less what the data is, (or how it's compressed).
_________________
Moron! You don't herd chickens with a shotgun!
--CoolMan