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INTRO(9) Kernel Developer's Manual INTRO(9) NAME intro - introduction to raster image software DESCRIPTION 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 whatever 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 8½(1) window. Examine similarly dis‐ plays an image and allows interactive examination of its pixel values. Picinfo displays the header of a picture 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- versa. Dumppic, gif2pic, picopic, and face2pic convert files in various alien formats to picfile(9.6) format. Pic2ps converts picfiles to encapsu‐ lated 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 48×48 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), quan‐ tize(9.1), resample(9.1), transpose(9.1), and xpand(9.1) for descrip‐ tions. Moto is an animator's command language. It converts concise descrip‐ tions of simultaneous processes overlapping in time into sequential command files suitable for producing frames of an animation. SEE ALSO 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 interactive bitmap graphics interface. INTRO(9)