Logo Questions Linux Laravel Mysql Ubuntu Git Menu
 

Are there standard 8-bit color palettes?

I'm attempting to reverse engineer a file format from a logging program. It seems to use a 1-2 byte field which may be used for label colors, as it seems to be the only thing that's unexplained. Short of iterating through other label colors and generating new output files (which is a pain in the ass, hence me trying to reverse-engineer the format in the first place), are there any standard 8-bit color palettes they may line up with? I've found some (e.g. the only 216 colors that are allowed on the web), but they're not enumerated in any particular way.

I believe 0x32 is light green (e.g. 0,255,0), 0x0A is teal cyan (0, 255, 255), and 0x28 is red. Each field may also include a trailing 0x00.

Or I could be totally wrong.

like image 654
Nick T Avatar asked Jun 26 '11 04:06

Nick T


People also ask

How many 8-bit colors are there?

The number, 256, is 2 raised to the 8th power or the 8-bit color depth. This means that each of the RGB channels has 256 shades so there are 256x256x256 or 16,777,216 colors in total in this 8-bit RGB system. An 8-bit color system is capable of producing over 16 million colors.

Is limited to the 8-bit palette with only 256 colors?

8-bit color graphics are a method of storing image information in a computer's memory or in an image file, so that each pixel is represented by 8 bits (1 byte). The maximum number of colors that can be displayed at any one time is 256 or 28.

Why does 8-bit have 256 colors?

How do bits and colors relate to one another? It's simple arithmetic. To calculate how many different colors can be captured or displayed, simply raise the number 2 to the power of the number of bits used to record or display the image. For example, 8-bits gives you 256 colors because 28=256.

How many standard Colours are there?

English, for example, has the full set of 11 basic colors: black, white, red, green, yellow, blue, pink, gray, brown, orange and purple.


1 Answers

Well, it could be one of the old standard VGA palettes. This is the one for mode 13h:

enter image description here

However, the numbers you posted seem to be off-by-one from the index into the usual ordering.

EDIT: Here are the 24-bit RGB values for the color components in a python formatted array. It is a bit long so be warned!

[0x000000, 0x0000a8, 0x00a800, 0x00a8a8, 0xa80000, 0xa800a8, 0xa85400, 0xa8a8a8, 0x545454, 0x5454fc, 0x54fc54, 0x54fcfc, 0xfc5454, 0xfc54fc, 0xfcfc54, 0xfcfcfc, 0x000000, 0x141414, 0x202020, 0x2c2c2c, 0x383838, 0x444444, 0x505050, 0x606060, 0x707070, 0x808080, 0x909090, 0xa0a0a0, 0xb4b4b4, 0xc8c8c8, 0xe0e0e0, 0xfcfcfc, 0x0000fc, 0x4000fc, 0x7c00fc, 0xbc00fc, 0xfc00fc, 0xfc00bc, 0xfc007c, 0xfc0040, 0xfc0000, 0xfc4000, 0xfc7c00, 0xfcbc00, 0xfcfc00, 0xbcfc00, 0x7cfc00, 0x40fc00, 0x00fc00, 0x00fc40, 0x00fc7c, 0x00fcbc, 0x00fcfc, 0x00bcfc, 0x007cfc, 0x0040fc, 0x7c7cfc, 0x9c7cfc, 0xbc7cfc, 0xdc7cfc, 0xfc7cfc, 0xfc7cdc, 0xfc7cbc, 0xfc7c9c, 0xfc7c7c, 0xfc9c7c, 0xfcbc7c, 0xfcdc7c, 0xfcfc7c, 0xdcfc7c, 0xbcfc7c, 0x9cfc7c, 0x7cfc7c, 0x7cfc9c, 0x7cfcbc, 0x7cfcdc, 0x7cfcfc, 0x7cdcfc, 0x7cbcfc, 0x7c9cfc, 0xb4b4fc, 0xc4b4fc, 0xd8b4fc, 0xe8b4fc, 0xfcb4fc, 0xfcb4e8, 0xfcb4d8, 0xfcb4c4, 0xfcb4b4, 0xfcc4b4, 0xfcd8b4, 0xfce8b4, 0xfcfcb4, 0xe8fcb4, 0xd8fcb4, 0xc4fcb4, 0xb4fcb4, 0xb4fcc4, 0xb4fcd8, 0xb4fce8, 0xb4fcfc, 0xb4e8fc, 0xb4d8fc, 0xb4c4fc, 0x000070, 0x1c0070, 0x380070, 0x540070, 0x700070, 0x700054, 0x700038, 0x70001c, 0x700000, 0x701c00, 0x703800, 0x705400, 0x707000, 0x547000, 0x387000, 0x1c7000, 0x007000, 0x00701c, 0x007038, 0x007054, 0x007070, 0x005470, 0x003870, 0x001c70, 0x383870, 0x443870, 0x543870, 0x603870, 0x703870, 0x703860, 0x703854, 0x703844, 0x703838, 0x704438, 0x705438, 0x706038, 0x707038, 0x607038, 0x547038, 0x447038, 0x387038, 0x387044, 0x387054, 0x387060, 0x387070, 0x386070, 0x385470, 0x384470, 0x505070, 0x585070, 0x605070, 0x685070, 0x705070, 0x705068, 0x705060, 0x705058, 0x705050, 0x705850, 0x706050, 0x706850, 0x707050, 0x687050, 0x607050, 0x587050, 0x507050, 0x507058, 0x507060, 0x507068, 0x507070, 0x506870, 0x506070, 0x505870, 0x000040, 0x100040, 0x200040, 0x300040, 0x400040, 0x400030, 0x400020, 0x400010, 0x400000, 0x401000, 0x402000, 0x403000, 0x404000, 0x304000, 0x204000, 0x104000, 0x004000, 0x004010, 0x004020, 0x004030, 0x004040, 0x003040, 0x002040, 0x001040, 0x202040, 0x282040, 0x302040, 0x382040, 0x402040, 0x402038, 0x402030, 0x402028, 0x402020, 0x402820, 0x403020, 0x403820, 0x404020, 0x384020, 0x304020, 0x284020, 0x204020, 0x204028, 0x204030, 0x204038, 0x204040, 0x203840, 0x203040, 0x202840, 0x2c2c40, 0x302c40, 0x342c40, 0x3c2c40, 0x402c40, 0x402c3c, 0x402c34, 0x402c30, 0x402c2c, 0x40302c, 0x40342c, 0x403c2c, 0x40402c, 0x3c402c, 0x34402c, 0x30402c, 0x2c402c, 0x2c4030, 0x2c4034, 0x2c403c, 0x2c4040, 0x2c3c40, 0x2c3440, 0x2c3040, 0x000000, 0x000000, 0x000000, 0x000000, 0x000000, 0x000000, 0x000000, 0x000000]

like image 105
Mikola Avatar answered Sep 27 '22 22:09

Mikola