intro - introduction to raster image software
Plan 9 provides a suite of commands and library routines to create and manipulate files
containing gray-scale and full-color images. Section 9 of this manual is divided into
subsections numbered like the main manual sections: 9.1 for commands, 9.2 for library
routines, 9.6 for file formats.
Picture files are two-dimensional arrays of multi-byte records with a textual header
describing the dimensions of the image, the algorithm used to encode the file, and what-
ever other information programs may wish to preserve. Picfile(9.6) describes the file
format; picopen(9.2) describes a library of routines to read and write picture files.
/bin/fb contains a collection of programs to manipulate picture files.
9v displays a picture file in an 81/2(1) window. Examine similarly displays an image and
allows interactive examination of its pixel values. Picinfo displays the header of a pic-
ture file on its standard output. Pcp copies picture files, modifying header attributes
as requested and updating the encoded picture array correspondingly. It can clip a sub-
window out of a picture, permute, delete, and rename channels, change the encoding type
and even convert full-color images to monochrome and vice-versa. Hed is a more brute-
force version of pcp that can apply an arbitrary sed(1) script to a picfile header. It
copies the image array verbatim and can thus convert precious images into garbage or vice-
Dumppic, gif2pic, picopic, and face2pic convert files in various alien formats to pic-
file(9.6) format. Pic2ps converts picfiles to encapsulated PostScript. Nohed removes the
header from a picture file. When applied to a TYPE=dump picture this converts it into the
ubiquitous `raw dump' format. Mugs is an interactive program to convert picfiles into
48x48 icons of the sort used by seemail (see mail(1) and face(6)).
Some commands create simple images out of whole cloth. Card writes an image of constant
color. Ramp creates an image that is one color at one edge and changes linearly to
another color at the opposite edge.
Aplot reads a square array of data points and draws an anti-aliased perspective plot of
the surface it defines.
There are numerous commands that read one or more images and write a modified image on
standard output. See remap(9.1), filters(9.1), floyd(9.1), he(9.1), lam(9.1), lerp(9.1),
logo(9.1), lum(9.1), quantize(9.1), resample(9.1), transpose(9.1), and xpand(9.1) for
Moto is an animator's command language. It converts concise descriptions of simultaneous
processes overlapping in time into sequential command files suitable for producing frames
of an animation.
Tom Duff, ``Raster Graphics in Plan 9''
Sections add(2), balloc(2), cachechars(2), subfalloc(2), bitblt(2), event(2), frame(2),
print(2), bit(3), layer(2), bitmap(6), and font(6) describe the standard Plan 9 interac-
tive bitmap graphics interface.