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Post Script:

​Handmade Gif is a Gif file I wrote by hand in binary. This of course is pointless, but I chose to do this as an exercise in order to familiarize myself with the basics of compression for no reason other then I wondered how it worked. Since Gif was the oldest common compression format, I picked it first. And because I was writing it by hand I picked a really small and easy one to do, which was a 2 pixel wide by 2 pixel high square. Black, White, on top of White, Black. U can see it re-sized above (the grey sections are aliasing which are not included in the oriignal, ... I swear!, download it and check it out. smile

Gif Code Explanation

header: 474946383961

image map size: 0200 0200

global color flag, not sorted, 1 bit per color, size of color table 2: 80

no background (unused): 00

no pixel aspect ratio: 00

black: 000000

white: FFFFFF

image separator: 2C

image distance from l / r in image map: 0000 0000

image size: 0200 0200

non interlaced, and no local colors (not sorted and no size): 00

size of LZW code chunks (=3): 02

length of LZW code section: 03

LWZ code: 448202

next LZW code size: 00

end of file: 3B

It is a 2 by 2 black and white checker GIF…