pamtopnm(1) [redhat man page]
pamtopnm(1) General Commands Manual pamtopnm(1) NAME
pamtopnm - convert PAM image to PBM, PGM, or PPM SYNOPSIS
pamtopnm [-assume] [pnmfile] All options may be abbreviated to the shortest unique prefix. DESCRIPTION
Reads a PAM image as input. Produces an equivalent PBM, PGM, or PPM (i.e. PNM) image, whichever is most appropriate, as output. pamtopnm assumes the PAM image represents the information required for a PBM, PGM, or PPM image if its tuple type is "BLACKANDWHITE", "GRAYSCALE", or "RGB" and its depth and maxval are appropriate. If this is not the case, pamtopnm fails. However, you can override the tuple type requirement with the -assume option. As with any Netpbm program that reads PAM images, pamtopnm also reads PNM images as if they were PAM. In that case, pamtopnm's functions reduces to simply copying the input to the output. But this can be useful in a program that doesn't know whether its input is PAM or PNM but needs to feed it to a program that only recognizes PNM. OPTIONS
-assume When you specify -assume, you tell pamtopnm that you personally vouch for the fact that the tuples contain the same data as belongs in the channels of a PBM, PGM, or PPM file. The depth must still conform, though, so to truly force a conversion, you may have to run the input through pamchannel first. But be careful with -assume. When you -assume, you make an -ass of u and me. SEE ALSO
pbmtopgm(1), pgmtopbm(1), pgmtoppm(1), ppmtopgm(1), pam(5), pnm(5), pbm(5), pgm(5), ppm(5) 03 August 2000 pamtopnm(1)
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pamstack(1) General Commands Manual pamstack(1) NAME
pamstack - stack planes of multiple PAM images into one PAM image SYNOPSIS
pamstack [-tupletype tupletype] [inputfilespec] All options may be abbreviated to the shortest unique prefix. DESCRIPTION
Reads multiple PAM or PNM images as input. Produces a PAM image as output, consisting of all the planes (channels) of the inputs, stacked in the order specified. The output is the same dimensions as the inputs, except that the depth is the sum of the depths of the inputs. It has the same maxval. pamstack fails if the inputs are not all the same width, height, and maxval. The tuple type is a null string unless you specify the -tuple- type option. pamchannel does the opposite of pamstack: It extracts individual planes from a single PAM. Use pamtopnm to convert a suitable PAM image to a more traditional PNM (PBM, PGM, or PPM) image. One example of using pamstack is that some Netpbm programs accept as input a PAM that represents graphic image with transparency informa- tion -- tuple type "RGBA". In Netpbm, such images were traditionally represented as two images - a PPM for the color and a PGM for the transparency. To convert a PPM/PGM pair into PAM(RGBA) input that newer programs require, do something like this: pamstack -tupletype=RGBA myimage.ppm myalpha.pgm | pamtouil >myimage.uil OPTIONS
-tupletype tupletype This specified the tuple type name to be recorded in the output. You may use any string up to 255 characters. Some programs recog- nize some names. If you omit this option, the default tuple type name is null. SEE ALSO
pam(5) AUTHOR
Copyright (C) by Bryan Henderson, San Jose CA 2000.08.05 01 May 2002 pamstack(1)