APAC 256 color mode 80x240 'interlaced': has this been done?

[+Stephen]

I created a 16MB ATR using MyDOS 4.53. This will let you get a ton more files on a disc It will also work for anyone able to use the FAT32 SIDE loader.

 

EDIT - sorry, the original ZIP was broken.

TurboBasicXLv1.5 - BGP Viewer_BIG.zip

[Aking]

working great

[Synthpopalooza]

You know this could work with other modes too ... HIP, CIN (15+11), and XL Paint (15+15 with color changes), amongst others. Or even mode 8 combos like 8+11 or 8+10.

 

Or using 9+9, but altering the chroma between values on opposite sides of the color wheel.

 

Also: Converting pictures into this mode should be easy, I've picked up a few tricks from my work with the ICE modes. G2F can render Graphics 9 files from any import. You can use the GIMP to render a 80x240 Graphics 11 file by reducing it to palette of the 15 chromas + black.

Edited September 25, 2013 by Synthpopalooza

[Roydea6]

BUGBYTE.ZIP

 

My first attempt worked, but not a good picture, just the first bmp I found.

Zork I picture.

 

*NOTE: I had to look to the source file to figure out the file extension 'BMP' was not needed with the Maker program.

Edited September 25, 2013 by rdea6

[bugbiter]

I created a 16MB ATR using MyDOS 4.53. This will let you get a ton more files on a disc It will also work for anyone able to use the FAT32 SIDE loader.

 

EDIT - sorry, the original ZIP was broken.

Thanks a lot, Stephen! Please repost, it's still broken. I hope I can use it with my sio2sd :-))

My viewer only supports up to I think 56 entries for the menu, as dos2.5, APE and AspeQt only show the standard 64 files in the dir.

[+Stephen]

Thanks a lot, Stephen! Please repost, it's still broken. I hope I can use it with my sio2sd :-))

My viewer only supports up to I think 56 entries for the menu, as dos2.5, APE and AspeQt only show the standard 64 files in the dir.

What is not working with the file? I used 7-zip, but standard ZIP algorithm.

[bugbiter]

i get an error from windows, archive is invalid.. I'm at work, will try again at home, maybe some restrictions here...

[+Stephen]

Well good news. I have successfully created an initial version of a PC convertor. It currently is not implementing Floyd-Steinberg dithering, but I was able to take a BMP image, resize it, and output a BGP file. The entire process takes 603ms

 

It's not really ready for public use yet, but the proof of concept is there. I will try to have an initial release ready by this weekend.

[bugbiter]

Boy, you are fast!

Looking forward to it

[+Stephen]

Working on one more little bug before I post some screenshots.

[Irgendwer]

Well good news. I have successfully created an initial version of a PC convertor. It currently is not implementing Floyd-Steinberg dithering, but I was able to take a BMP image, resize it, and output a BGP file. The entire process takes 603ms

 

It's not really ready for public use yet, but the proof of concept is there. I will try to have an initial release ready by this weekend.

 

Thought about utilizing Image Magick? (Easy, quick and maintainable...)

 

(A further improvement could consist in using (shifted) mode 10 for virtual resolution enhancement...)

[+Stephen]

 

Thought about utilizing Image Magick? (Easy, quick and maintainable...)

 

(A further improvement could consist in using (shifted) mode 10 for virtual resolution enhancement...)

I have no idea about that. I will gladly post the full source to this convertor - it is quite simple.

 

Bug is fixed, but the GF got here, so we are going out to dinner. I will post screenshots and maybe a demo video when we get back.

[bugbiter]

I was thinking of combining with shifted Gr.10 lines as well to achieve the HIP effect.

 

To get the HIP effect, you have to alter gr.9 and gr. 10 on each line, but we are also forced to alter chroma and luma each line for APAC mode so either luma or chroma will always be gr.10.

 

for example:

 

even fields:

1: gr.9 luma

2: gr.10 chroma

3: gr.9 luma

4: gr.10 chroma

etc...

 

odd fields:

1: gr.10 chroma

2: gr.9 luma

3: gr.10 chroma

4: gr.9 luma

etc..

 

That being the case, the HIP effect will not show because luma is always the same mode and therefore never shifted 1 color clock..

 

SAD!

 

Where's JAC! ? I think he was the first to discover the gr10 shift. Perhaps he has an idea about that.

[Rybags]

Gr. 10 shift was discovered some time ago although the modes using it took some time in cases.

 

TIP mode probably most useful of the common techniques, ie fixed luma one line, alternate between Gr. 9 and Gr. 10 the next for perceived 160 resolution.

 

I experimented some time back with similar technique to what you've described. Increased chroma perception is desirable but not near as much as better luma perception.

 

Although that said it's still a useful technique.

 

The possibilities are vast although not all useful. You could have a mode where both luma and colour perception are doubled via alternating Gr. 10 and the other modes. Although limitations creep in since if using Gr. 10 lines for both types you need to do all the palette changes.

 

Narrow mode, use of PMGs etc. can all contribute.

[+Stephen]

OK guys, here is a photo series of alpha version 0.01. No attempt at speed or optimization has been made - this is literally the first run of it producing correct output. The photos are:

1. Initial layout - sparse but functional.
2. Palettes available to use (any 768 byte in RGB order will do).
3. At this stage, the file has been loaded and converted.
4. This is the uber-awesome bugbiter picture loader showing the newly created image (via Altirra and the H: device)
5. Image loading screen - note the Description.
6. A nice Atari rendition of some dude who needs a haircut.
7. A PNG of the original BMP file I used (BMPs will not display inline)

 

NOTES:

• I currently do not have dithering coded.
• Palattes automatically load from the "Palettes" directory (place where EXE runs).
• The "Debug Files" consist of:
  • The resized & flipped BMP (bass_resized24bpp.bmp)
  • A RAW image of the resized file using colours from the Palette (bass_resized24bpp.raw)
  • The raw 9560 byte Luma (bass_test.bri) and Chroma (bass_test.hue) files, using Atari colours (i,e, 0-255) - note, these files are in "packed GTIA mode" (2 pixels per byte
• The debug files get auto-named, based on the selected filename.
• Loading non-BMP images is currently not supported but should be a trivial addition.
• I would like to experiment with colour distance algorithms, as I am currently only using RGB distance @ double precision.

[Synthpopalooza]

The possibilities are vast although not all useful. You could have a mode where both luma and colour perception are doubled via alternating Gr. 10 and the other modes. Although limitations creep in since if using Gr. 10 lines for both types you need to do all the palette changes.

 

Narrow mode, use of PMGs etc. can all contribute.

One possibility, which requires no color changes, is using two Graphics 10 screens. One is rendered as a greyscale, but the Graphics 10 chroma palette is reorganized to match the greyscale palette, then the same chroma palette is used for both renders. This basically gives you a 45 color screen in Graphics 10 without color changes. You could even do full-screen changes instead of scanlines, because checkerboard dithering can be used on the whole screen to reduce flicker. This is a technique I used in my ICE Super 10 mode.

[+Stephen]

And I just love that one almost 3D...

boobs1.JPG

Well, here's a medical version FLIR image - original, then converted version.

 

flir_test.zip (This is the BGP you can load on real machine)

[bugbiter]

looking very good without dithering. Those pictures are quite colourful, Floyd steinberg will help a lot with less saturated areas..

 

keep on coding, I can't wait!!

[Aking]

Stephen, Looking forward to it too.

[Irgendwer]

 

I'd certainly like to look at them.

 

Ok, took a while, but here they are.

 

Please note: Even if the painting program here is also called 'Paint256' it has nothing to do with the APAC one from 'Charlie Chaplin': Contrary to 'his' one, this version interlaces - like the fractal application. (And yes, both are 'somewhat' sllllooowww...)

HCA2GFX.zip

[bugbiter]

Aahh, memories.. wunderbar!

 

this started it all for me.

[+CharlieChaplin]

 

Ok, took a while, but here they are.

 

Please note: Even if the painting program here is also called 'Paint256' it has nothing to do with the APAC one from 'Charlie Chaplin': Contrary to 'his' one, this version interlaces - like the fractal application. (And yes, both are 'somewhat' sllllooowww...)

 

Hmmm,

 

`my` version (not produced by me, not coded by me!) is Paint 256, the type-in listing from the german Happy Computer magazine. Could it be that your version is the once commercially sold program Digi-Paint or what else is the source ?!? This is no rhetoric question, I am asking seriously for an answer, because my original Digi-Paint diskette does not work and nowadays this disk seems hard to find (and I have no clue whats on the Digi-Paint disk). Afaik, the same authors also created Escal-Paint and there are some demo-disks in the Abbuc PD library available under the name "Amiga Show" (pics in Digi-Paint / 123 sectors format, PD numbers 206, 207 and 208).

 

-----

Taquart Interlace Picture (TIP)

===============================

 

This text is a translation of the

 

original article printed (yes!

 

printed!) in Polish magazine

 

"Atarynka", no. 2/2002.

 

This article describes a new graphics

 

mode, capable of showing 256 colors

 

in resolution 160 x 119.

 

 

TIP

---

 

TIP is an enhacement of HIP,

 

adding the colors. The way colors

 

are added is so simple, that it's

 

odd why this mode wasn't invented

 

at the same time as HIP. This method

 

has been used so far for 256-color

 

modes (APC, ILC) and coloring MIC

 

pictures (CIN mode). Colors are

 

added by GTIA 11 lines. These lines

 

are displayed every frame, in same

 

place, with same contents. The line

 

of colors is always directly above

 

corresponding line of shades.

 

Of course nothing is for free, so we

 

pay for the colors with twice lower

 

vertical resolution and introduction

 

of dark lines. The good thing is

 

that pixels are now squares, which

 

is convenient for conversion.

 

We may consider "interlacing"

 

the colors, i.e. displaying distinct

 

colors in different frames. You have

 

to check in practice if it gives

 

a good effect.

 

 

Displaying

----------

 

The way of displaying TIP mode

 

is a simple enhancement of displaying

 

HIP. The GTIA color registers have

 

following values:

 

$00 $02 $04 $06 $08 $0A $0C $0E $00.

 

On the first screen we see:

 

- first line of colors (GTIA 11)

 

- first line of shades (GTIA 9)

 

- second line of colors (GTIA 11)

 

- second line of shades (GTIA 10)

 

...

 

and on the second one:

 

- first line of colors (GTIA 11)

 

- first line of shades (GTIA 10)

 

- second line of colors (GTIA 11)

 

- second line of shades (GTIA 9)

 

...

 

As you can see, TIP mode without

 

interlacing the colors takes less

 

memory/disk space than HIP (ca. 12 KB

 

vs 16 KB for a picture of typical

 

size).

 

 

Conversion

----------

 

For easy conversions you may

use the PC progam BMP2TIP.EXE

or TIPCONV.EXE by EPI. Simply downsize

your BMP picture to a minimum of

160x1 and a maximum of 160x119 and

256 colors (uncompressed, please).

Then copy the new created TIP

picture to the little Atari and use

the A8 program TIPVIEW.COM by

EPI to view it...

 

-----

 

Think I read somewhere, that the Gr.10 shift happens, if you first switch to Gr. 8 and then to Gr. 10 (or first to Gr. 10, then to Gr. 8 and back again to Gr. 10), not sure if thats true. The end result is the pixel shifting, giving a resolution of 160x200 / 160x239 pixels instead of the normal 80x pixels. This pixel-shifting seems only to happen in Gr. 10 and not in the other GTIA modes 9 and 11. Maybe someone wants to try Gr. 10+11 with Gr. 10 shift active for 160x200 or 160x239 pixels resolution, Gr. 10 giving 8 different lumas like 0,2,4,6,8,10,12,14,0 (where 0 = black and 14 = white); and Gr. 11 giving 16 colours. This would result in 8 lumas x 16 colours =128 colours in 160x200/239 resolution. (Yes, I always ask for this, because I would like to see the result and compare it to RIP with Gr. 10+9).

 

-Andreas Koch.

Edited September 26, 2013 by CharlieChaplin

[bugbiter]

Andreas, I think your question is answered. Take a look at the Happy-computer Sonderheft scans from Irgendwer- in the title picture you can see the purple two-line menu at the top of the screen like in his paint256 program.

I remember too that the Happy-Computer one was in the flicker mode...

[+CharlieChaplin]

Hmmm strange,

 

so it looks like "my" program is NOT from Happy Computer... the strange thing now is, we have two programs that both use the name "Paint 256":

 

- "my" program which uses 256-colour pictures with 62 sectors on disk, 80x96 pixels resolution, no-flicker (due to PAL colour blending/bleeding)

- Irgendwer`s / Happy Computer 256-colour program which uses pictures with 123 sectors on disk, 80x192 pixels resolution and flicker (via interlace/interleave)...

 

Now I would like to know the source of my Paint 256 program, since I always assumed it is the one from Happy Computer... -Andreas Koch.

 

EDIT: - TB XL listing of Irgendwer`s Paint 256 program says author = Stephan Gehrle and Francois... (most likely Happy Computer)...

- TB XL listing of my Paint 256 program says author = A. Slaager (could that be the dutch SAG / Stichting Atari Gebruikers or dutch Pokey magazine ? Besides, I got this disk from the Abbuc PD library, PD number 205)

Edited September 27, 2013 by CharlieChaplin

[+Stephen]

Excellent - I now have Floyd-Steinberg dithering enabled. Here is a comparison shot :

 

EDIT - God I love the .NET library. I can use this convertor with any image format, and I did not have to write one single line of code! When I don't let the machine write any of the extraneous debug files, full image conversion with dithering happens in 311ms.