Right, and we all know that most web pages consist of large gray areas.
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And other way to save memory is color reduction 16/24 bit bitmaps to dithered 256 colors bitmaps.
Dithering large images on a 200 MHz CPU? Not to mention having a decent median cut algorithm that doesn't make your images look like shotgun impacts, retains readability, and is fast enough? Hardly going to happen
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Or maybe down scaling images from 1/1 to 1/2 or 1/4 of the original resolution.
And use a Lens docky to read the page, eh?
I still think that paging is the best solution, more so since it doesn't require a load of effort just to support old machines.
Seriously, if you do want to contact me write me a mail. You're more likely to get a reply then.
Well it can be done where fast, there are some techniques used whit web cam?s, and you really only need to do it once, we are not talking about rendering a 24 bit image as 256 colors, I?m talking about converging the image in to 256 colors, to save ram, so download the image convert it in 256 or downscale the image, now it takes less memory.
You can easily view mpegs on 200 Mhz, so 200 Mhz is not a problem.
And showing a 256 colors image on 24bit/16bit display is quite fast, a simple loop and 256 colors lookup table is all that is needed, the lookup table can even be in the native pixel-format, so you can even save time of converting it to the display.
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And use a Lens docky to read the page, eh?
No was not talking about the text arias on page, only the pictures on the web page.
Scaling techniques can be where fast as shown many Amiga demos.
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I still think that paging is the best solution, more so since it doesn't require a load of effort just to support old machines.
I can easily agree whit that in a perfect world, but many classic Amiga?s do not have DMA modes only PIO modes.
Edited by LiveForIt on 2008/3/4 18:32:56
(NutsAboutAmiga)
Basilisk II for AmigaOS4 AmigaInputAnywhere Excalibur and other tools and apps.
we are not talking about rendering a 24 bit image as 256 colors, I?m talking about converging the image in to 256 colors, to save ram, so download the image convert it in 256 or downscale the image, now it takes less memory.
Not enough for the extremely bad results you'd get, it would still be 16 bit (8 bit alpha + 8 bit CLUT). The alpha part is required for everything, incl. text rendering. The only option with still usable results would be using 24 bit (A8R5G6B5) instead of the currently used 32 bit (A8R8G8B8). At least as long as the bug in ticket #111 isn't fixed using less than 8 bit for alpha, for example a 20 bit A5R5G5R5 format, would probably not be usable. I wont reimplement the graphics functions for such special formats anyway, there are still more that enough other things to do ...
The next version will need 20-30 MB less RAM for large pages, it did allocate the new page before freeing the old one when resizing them, which should make it usable for a lot of pages on Amigas with only 128 MB RAM.
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You can easily view mpegs on 200 Mhz, so 200 Mhz is not a problem.
Watching postage stamp sized mpegs on a 1280x1024 screen might be OK, you can display them on a 320x240 screen instead of you want to be able to recognise something, but for web pages that's no option
[quote] The next version will need 20-30 MB less RAM for large pages, it did allocate the new page before freeing the old one when resizing them, which should make it usable for a lot of pages on Amigas with only 128 MB RAM.
You can easily view mpegs on 200 Mhz, so 200 Mhz is not a problem.
You're kidding, right? Have you tried watching a DVD on a Classic Amiga? I don't think so.
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Scaling techniques can be where fast as shown many Amiga demos
Scaling is trivial if you don't care about the quality. If you zoom a small image up to a larger size and you don't apply filtering, the result will invariably look crappy, especially if you are using fractional scaling values.
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I can easily agree whit that in a perfect world, but many classic Amiga?s do not have DMA modes only PIO modes.
Considering the speed of the Classic Amiga's memory, the speed difference will probably not be that drastic. Besides, paging is demand-driven. I tried copying files to ram-disk with the pager enabled and you didn't even notice a difference on the AmigaOne. You could measure one, but the drop was so insignificant that it didn't matter (which also is an indication of how slow RAM Disk is).
I haven't tried it on the classic yet (lack of time), but I am quite sure it will be perfectly usable. Not a speed demon, but that would be true for any sort of trickery you had in mind as well. Only that using paging will not require someone to go through the effort of actually coding all this - it works for all memory-hungry applications.
Seriously, if you do want to contact me write me a mail. You're more likely to get a reply then.
Which reminds me that the Radeon chipsets support an 8 bit truecolor RGB format R3G3B2... not alpha though
I could use something else with 8 bit/pixel which is supported by more gfx cards: A YUV411 PIP for the browser window Would even be usable for the images, but text would get unreadable ...
You're kidding, right? Have you tried watching a DVD on a Classic Amiga? I don't think so.
I was think more like the Freespace introduction video, besides a web browser does not need many frames per secedes.
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Scaling is trivial if you don't care about the quality. If you zoom a small image up to a larger size and you don't apply filtering, the result will invariably look crappy, especially if you are using fractional scaling values.
I have done some experiments, scaling a image to double size can be done, and hardly notice it's scaled, scaling to 4 times the size you notice big quality difference.
Down scaling the image to half of the original size will save 75% of the image memory.
Formula: A=H*W
Height=100, Width=100 A=100*100 = 100000 pixels
Height=50, Width=50 A=50*50 = 2500 pixels
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I haven't tried it on the classic yet (lack of time), but I am quite sure it will be perfectly usable. Not a speed demon, but that would be true for any sort of trickery you had in mind as well. Only that using paging will not require someone to go through the effort of actually coding all this - it works for all memory-hungry applications.
Maybe your right, but I have seen lots of classic users already complain about disk speed, maybe because they do not have PowerPC native drivers, maybe some thing else.
Edited by LiveForIt on 2008/3/5 20:13:03
(NutsAboutAmiga)
Basilisk II for AmigaOS4 AmigaInputAnywhere Excalibur and other tools and apps.
I was think more on lines of Freespace introduction video, besides a web browser does not need many frames per secedes.
The Freespace intro movies are Quicktime, not MPEG. They were seriously downgraded from the original ones, too.
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Down scaling the image to half of the original size will save 75% of the image memory.
And reduces the quality accordingly. I am well aware that half the image size will save 75% of the memory required (after all, tiling an image four times will double its width and height), but you are missing the point(s):
- The quality suffers seriously, images get blocky. Just take the banner at the top, you will not be able to read the "LRG software" anymore if you half the image.
- The effort required for this (programming-wise) cannot be justified for the few people that would actually benefit from it.
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Maybe your right, but I have seen lots of classic users already complain about disk speed, maybe because they do not have PowerPC native drivers, maybe some thing else.
It is because of the slow speed of the mainboard. Anything on the Amiga mainboard is slow, there is nothing you can do about it. RAM is slow (dead slow actually). AGA is slow. IDE is slow. Let's face it, today's cell phones usually have more CPU power and faster video access than the average classic Amiga.
Seriously, if you do want to contact me write me a mail. You're more likely to get a reply then.
How about grayscale and maybe reserving 2 bits for Alfa blending. AACCCCCC (36 gray colors) (4 alfa values)
4 different Alfa blending values (0% , 33.33% , 66.66% and 100%)
The only usable greyscale format would be 16 bit (8 bit alpha, 256 grey levels). Although you only get 32 grey levels on a 15 bit screenmode using a 13 bit format with 32 levels is no option, the graphics operations done until it's finally displayed on the screen would remove too much information.
As I wrote already I wont implement anything like that, but if someone else really wants to do it I can move the graphics functions into a shared object, that way whoever does it only has to rebuild a few 100 KB sources with about 50 functions instead of the complete OWB, and it would make it possible to switch between different formats (32 bit, 24 bit A8R5G6B5, 16 bit greyscale, ...) by replacing the gfx shared object.