pix — Color RGB image file format and utilities


A pix file contains sequences of pixels. Each pixel is stored as three unsigned chars, first red, then green, then blue. The intensity of each color ranges from 0 ("off") to 255 ("on"). The first pixel in a pix file is the lower left corner of the image. The pixels proceed from left-to-right across each scanline, with scanlines being written from the bottom to the top of the image.

By convention, pix images are usually square, and thus their dimensions can be determined by the file size. If this is not the case, often only the file width need be known by a program reading the file. History has left us with two "standard" sizes, 512x512 and the "higher" 1024x1024. A common practice for other file sizes is to include the file width in the filename.

At some time in the future pix files will probably get self-typing headers so that parameters such as their size can be automatically determined by programs.


pix-fb display a .pix format image on a framebuffer.

fb-pix produce a .pix file from a framebuffer image.

pix-bw convert a .pix file to a black and white .bw file.

bw-pix convert a black and white .bw file to a .pix file.

ap-pix convert an Applicon Color Plotter file to a .pix file.

pixtile combine several small .pix files into one large one.

pixstat gives statistics concerning a .pix file.

pixhist displays a color histogram on a framebuffer.

pixhist3d display three views of an RGB color space histogram on a framebuffer.

pixhist3d-plot3 unix plot of RGB color space utilization.

pixdiff shows which pixels/colors differ between two .pix files.

pixrect extracts an arbitrary rectangle from a .pix file.

pixrot rotate, reverse, or invert a .pix file.

pixscale scale a .pix file up or down.

pixfilter a collection of 3x3 kernel filters for .pix files.

bw3-pix merges three .bw files into one .pix file.

pix-bw3 separates .pix file RGB colors into three .bw files.




brlcad(1), bw(5), and above named programs.




This software is Copyright (c) 1989-2016 by the United States Government as represented by U.S. Army Research Laboratory.


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