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	README - farbfeld - suckless image format with conversion tools
	git clone git://git.suckless.org/farbfeld
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	README (2973B)
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	9 WHAT IS FARBFELD?
	10 Farbfeld is a lossless image-format designed to be
	11 parsed and piped easily. It is probably the simplest
	12 image-format you can find (see FORMAT).
	13 It does not have integrated compression, but allows
	14 compression algorithms to work with it easily by adding
	15 little entropy to the image data itself. This beats PNG
	16 in many cases.
	17 Given the free choice of compression algorithms, it
	18 is trivial to switch to better and faster ones as they
	19 show up in the future.
	20
	21 HOW DO I USE THE TOOLS?
	22 encoding:
	23 png2ff < example.png > example.ff
	24 png2ff < example.png \| bzip2 > example.ff.bz2
	25
	26 decoding:
	27 ff2png < example.ff > example.png
	28 bzcat example.ff.bz2 \| ff2png > example.png
	29
	30 bzip2 is used in this example and a recommended
	31 compression algorithm. Of course you are free
	32 to use something else.
	33
	34 WHY FARBFELD?
	35 Current image-formats have integrated compression,
	36 making it complicated to read the image data.
	37 One is forced to use complex libraries like libpng,
	38 libjpeg, libjpeg-turbo, giflib and others, read the
	39 documentation and write a lot of boilerplate in order
	40 to get started.
	41 Farbfeld leaves this behind and is designed to be as
	42 simple as possible, leaving the task of compression
	43 to outside tools.
	44 The simple design, which was the primary objective,
	45 implicitly lead to the very good compression
	46 characteristics, as it often happens when you go with
	47 the UNIX philosophy.
	48 Reading farbfeld images doesn't require any special
	49 libraries. The tools in this folder are just a toolbox
	50 to make it easy to convert between common image formats
	51 and farbfeld.
	52
	53 HOW DOES IT WORK?
	54 In farbfeld, pattern resolution is not done while
	55 converting, but while compressing the image.
	56 For example, farbfeld always stores the alpha-channel,
	57 even if the image doesn't have alpha-variation.
	58 This may sound like a big waste at first, but as
	59 soon as you compress an image of this kind, the
	60 compression-algorithm (e.g. bzip2) recognizes the
	61 pattern that every 48 bits the 16 bits store the
	62 same information.
	63 And the compression-algorithms get better and better
	64 at this.
	65 Same applies to the idea of having 16 bits per channel.
	66 It sounds excessive, but if you for instance only have
	67 a greyscale image, the R, G and B channels will store
	68 the same value, which is recognized by the compression
	69 algorithm easily.
	70 This effectively leads to filesizes you'd normally only
	71 reach with paletted images, and in some cases bzip2 even
	72 beats png's compression, for instance when you're dealing
	73 with grayscale data, line drawings, decals and even
	74 photographs.