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Old 28 July 2017, 13:53   #1
cmsj
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Hot new Amiga Disk Images

https://imgur.com/a/Db1vz

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Old 28 July 2017, 14:03   #2
Sinphaltimus
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Nice. what do you use to create these "images"? Those are pretty neat to look at.
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Old 28 July 2017, 14:08   #3
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Imagemagick. I ran this on my Linux machine:

Code:
for filename in *.adf ; do 
  convert -depth 8 -size 11264x80 gray:"$filename" -scale 100%x800% -flip -virtual-pixel 'transparent' +distort Polar '1024 256' "/home/cmsj/Downloads/AmigaADFImages/$filename".png
done
It's not *really* a true representation because it's reading 8 bits for each pixel, but I think it makes the visualisation nicer to look at. Edit: It's also a total lie because this is reading ADF files which aren't anything like a representation of the track data on disk, just the filesystem on the disk. Also there is twice as much data as there should be, since the disks are double sided and that isn't accounted for here. Valid future work would be writing some code that uses the IPF library to get raw track data, and visualising it bit-for-bit. I leave that as an exercise for the reader

If anyone cares, the only real magic value in here is the 11264x80 size parameter. Ignoring the polar distortion (which is what makes the image round), that size means that imagemagick will read 11264 bytes for each row of the image, and there will be 80 rows. These values are chosen because a typical Amiga DSDD disk has 80 tracks (cylinders), each of which is 2 heads × 11 sectors × 512 bytes/sector. 2*11*512==11264).

In an ideal world, I would spend some time to do this with bit-for-bit accuracy using IPF formatted files, but I don't have the time really, nor do I have IPF files of all the original C= disks. I just used the Cloanto ADF files

Last edited by cmsj; 28 July 2017 at 17:58.
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Old 28 July 2017, 17:30   #4
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Added another image to the gallery, but it's only interesting to me - image of the 1.2GB drive that was in my A1200 when it died in 1998ish
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Old 28 July 2017, 17:34   #5
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Still cool to look at, i imagine using some of these for textures and bump maps in 3d objects.
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Old 30 August 2017, 15:35   #6
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If anyone is interested, I started doing some work on a libipf version of this, but I've stalled and I don't think I'm likely to push it any further.

My code is at https://github.com/cmsj/capsimg/blob...amigadiskviz.c and the repo its in is forked from Frode's capsimg repo (which is the source for FS-UAE's CAPS image plugin).

I did all of this on macOS, but it should also build fine on Linux:

./bootstrap
./configure
make
gcc amigadiskviz.c -o amigadiskviz
./amigadiskviz foo.ipf top.data bottom.data

the two .data files will contain the tracks from the relevant side of the disk, each padded out to the length of the longest track found on either side of the disk.

Before writing any PNG creation code, I quickly tried some options with the data files and Imagemagick and I don't think the visualisations look as nice as the ones I made at the top of this thread, which is what has caused me to stop working on this code.

I'm just trying to make a nice poster for my office wall, but if someone wants to take this code further, fix up all my stupid mistakes, and make a cute tool for visualising Amiga IPFs, please feel free - any code that I can claim to copyright (which is little, most of amigadiskviz.c is copied/reformatted from either FS-UAE or libipf) can be considered to be under a "do anything you like with this" license
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Old 13 September 2017, 18:52   #7
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This is so cool, really really love it.
Now here's my question: can you take an image and revert it back to a disk image?
I don't understand Imagemagick well yet, but it would be cool to add color, too.
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Old 14 September 2017, 00:41   #8
grelbfarlk
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That is pretty weird, I like it. Probably can't turn it back to a real disk image at least not with .jpg, since it's a lossy compression unless they're high enough resolution. Probably with TGA or something that isn't compressed.
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Old 15 September 2017, 17:10   #9
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Yeah uncompressed would be fine.
Maybe something like BMP or whatever.
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Old 15 September 2017, 19:28   #10
cmsj
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Quote:
Originally Posted by Akira View Post
This is so cool, really really love it.
Now here's my question: can you take an image and revert it back to a disk image?
I don't understand Imagemagick well yet, but it would be cool to add color, too.
No, you couldn't reconstruct the original disk image from these pictures:
  1. Each pixel in the rectangular image that ImageMagick produces initially, is a greyscale representation of 8 bits of disk data, which probably makes it tricky to recover the precise original 8 bits
  2. The polar transform that ImageMagick subsequently does to bend the rectangle around a circle, is lossy
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Old 15 September 2017, 20:01   #11
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Okay, thanks for your answer, I Was just getting weird ideas
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