.pbn and .pal are sister image file formats representing indexed-color mappings (.pbn) and indexed color palettes (.pal) .pbn (paint-by-numbers) is a plaintext human and computer-legible image format representing indexed color mappings. the first line in a pbn file must specify, dilenated by whitespace characters: single hexadecimal integer value representing the image hex_digits single hexadecimal integer value representing the image width single hexadecimal integer value representing the image height and terminate with a newline character. a column of pixels is defined by any sequence of one or more hexadecimal values of length hex_digits, where hex_digits multiplied by 16 determines the maximum number of possible unique colors in the image. columns exceeding width specified in the first line of the file will be ignored. columns shorter than width specified in the first line of the file risk undefined behaviour in interpreting programs. a new row of pixels is defined by a new line character. rows exceeding height specified in the first line of the file will be ignored. each hexadecimal value within a column represents an index to be used by interpreting programs to render images when paired with a .pal (palette) file. shorthand hexadecimal form is not permitted. example: 1 10 10 0000001111000000 0000012222100000 0000123333210000 0000131111310000 0001311111131000 0001313113131000 0011211111121100 0012131111312100 0012223223222100 0012122332212100 0133122222213310 0111122222211110 0011222222221100 0001212222121000 0000112222110000 0000001111000000 .pal (palette) is a plaintext human and computer-legible format representing indexed color mappings for .pbn and other image formats. new line character-dilineated list of hexadecimal rgb or rgba color values, where 2 bits are alloted for each channel. rgb and rgba color values should not be interlaced in a single .pal file, the character width of the first color defined in a .pal file will be used to determine if the palette contains exclusively rgb colors or exclusively rgba colors. shorthand hexadecimal form is not permitted. example: FFFFFF 000000 186BE7 FFEFA6 a rudimentary image viewer is available at https://deianeira.co/view-pbn additional vague considerations: these formats are still being fleshed out and tested, their intention is to provide the dumb-simplest uncompressed image format for small tools and games these formats are intended for a computing environment with minimal or no network consideration the .pbn format could probably be used in isolation to represent tile maps (arrays) of other .pbn images this document needs revision, it's a scratch pad for now credit: wizard example sprite from https://opengameart.org/content/blowhard-2-blow-harder by https://opengameart.org/users/surt