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pnmshear(1) [minix man page]

pnmshear(1)                                                   General Commands Manual                                                  pnmshear(1)

NAME
pnmshear - shear a portable anymap by some angle SYNOPSIS
pnmshear [-noantialias] angle [pnmfile] DESCRIPTION
Reads a portable anymap as input. Shears it by the specified angle and produces a portable anymap as output. If the input file is in color, the output will be too, otherwise it will be grayscale. The angle is in degrees (floating point), and measures this: +-------+ +-------+ | | | | OLD | | NEW | | |an +-------+ |gle+-------+ If the angle is negative, it shears the other way: +-------+ |-an+-------+ | | |gl/ / | OLD | |e/ NEW / | | |/ / +-------+ +-------+ The angle should not get too close to 90 or -90, or the resulting anymap will be unreasonably wide. The shearing is implemented by looping over the source pixels and distributing fractions to each of the destination pixels. This has an "anti-aliasing" effect - it avoids jagged edges and similar artifacts. However, it also means that the original colors or gray levels in the image are modified. If you need to keep precisely the same set of colors, you can use the -noantialias flag. This does the shearing by moving pixels without changing their values. If you want anti-aliasing and don't care about the precise colors, but still need a lim- ited *number* of colors, you can run the result through ppmquant. All flags can be abbreviated to their shortest unique prefix. SEE ALSO
pnmrotate(1), pnmflip(1), pnm(5), ppmquant(1) AUTHOR
Copyright (C) 1989, 1991 by Jef Poskanzer. 12 January 1991 pnmshear(1)

Check Out this Related Man Page

pnmpaste(1)                                                   General Commands Manual                                                  pnmpaste(1)

NAME
pnmpaste - paste a rectangle into a portable anymap SYNOPSIS
pnmpaste [-replace|-or|-and |-xor] frompnmfile x y [intopnmfile] DESCRIPTION
Reads two portable anymaps as input. Inserts the first anymap into the second at the specified location, and produces a portable anymap the same size as the second as output. If the second anymap is not specified, it is read from stdin. The x and y can be negative, in which case they are interpreted relative to the right and bottom of the anymap, respectively. This tool is most useful in combination with pnmcut. For instance, if you want to edit a small segment of a large image, and your image editor cannot edit the large image, you can cut out the segment you are interested in, edit it, and then paste it back in. Another useful companion tool is pbmmask. pnmcomp is, a more general tool, except that it lacks the "or," "and," and "xor" functions. pnmcomp allows you to specify an alpha mask in order to have only part of the inserted image get inserted. So the inserted pixels need not be a rectangle. You can also have the inserted image be translucent, so the resulting image is a mixture of the inserted image and the base image. The optional flag specifies the operation to use when doing the paste. The default is -replace. The other, logical operations are only allowed if both input images are bitmaps. These operations act as if white is TRUE and black is FALSE. All flags can be abbreviated to their shortest unique prefix. SEE ALSO
pnmcomp(1), pnmcut(1), pnminvert(1), pnmarith(1), pbmmask(1), pnm(5) AUTHOR
Copyright (C) 1989, 1991 by Jef Poskanzer. 21 February 1991 pnmpaste(1)
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