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diff --git a/upstream/debian-bookworm/man1/ppmchange.1 b/upstream/debian-bookworm/man1/ppmchange.1 new file mode 100644 index 00000000..1759080a --- /dev/null +++ b/upstream/debian-bookworm/man1/ppmchange.1 @@ -0,0 +1,178 @@ +\ +.\" This man page was generated by the Netpbm tool 'makeman' from HTML source. +.\" Do not hand-hack it! If you have bug fixes or improvements, please find +.\" the corresponding HTML page on the Netpbm website, generate a patch +.\" against that, and send it to the Netpbm maintainer. +.TH "Ppmchange User Manual" 1 "December 2016" "netpbm documentation" + +.SH NAME +ppmchange - change all pixels of one color to another in a PPM image + +.UN synopsis +.SH SYNOPSIS + +\fBppmchange\fP + +[\fB-closeness=\fP\fIcloseness_percent\fP] +[\fB-remainder=\fP\fIremainder_color\fP] +[\fB-closeok\fP] +[\fIoldcolor newcolor\fP] ... +[\fIppmfile\fP] + +.UN examples +.SH EXAMPLES + +.nf +\fBppmchange red blue redimage.ppm >blueimage.ppm\fP + +\fBppmchange red red -remainder=black myimage.ppm >redblack.ppm\fP + +\fBppmchange -closeness=10 white white black black\fP + + +.fi + +.UN description +.SH DESCRIPTION +.PP +This program is part of +.BR "Netpbm" (1)\c +\&. +.PP +\fBppmchange\fP reads a PPM image as input and changes all pixels of +color \fIoldcolor\fP to color \fInewcolor\fP. + +You may specify up to 256 oldcolor/newcolor pairs on the command line. +\fBppmchange\fP leaves all colors not mentioned unchanged, unless you +specify the \fB-remainder\fP option, in which case they are all +changed to the single specified color. +.PP +You can specify that colors similar, but not identical, to the ones +you specify get replaced by specifying a "closeness" factor. +.PP +Specify the colors as described for the +.UR libnetpbm_image.html#colorname +argument of the \fBpnm_parsecolor()\fP library routine +.UE +\&. +.PP +If a pixel matches two different \fIoldcolor\fPs, \fBppmchange\fP +replaces it with the \fInewcolor\fP of the leftmost specified one. +.PP +The maxval of the output image is the same as that of the input +image. If a \fInewcolor\fP you specify cannot be exactly represented +in that maxval, \fBppmchange\fP assumes a color that is as close as +possible to what you specified but can be represented with your +maxval. Unless you specify the \fB-closeok\fP option, +\fBppmchange\fP issues a warning that it is using an approximation. +.PP +A common way that you can have this maxval problem, where the color +you specify cannot be represented with your maxval, is that your input +is a PBM (black and white) image that you are colorizing. The maxval +in this case is 1, which severely limits the colors to which you can +change. To avoid this problem, use \fBpamdepth\fP to make the maxval +of your input something consistent with your colors. 255 is usually a +good choice. +.PP +Before Netpbm 10.22 (April 2004), \fBppmchange\fP always behaved as +if the user specified \fB-closeok\fP, and there was no \fB-closeok\fP +option. + + +.UN options +.SH OPTIONS +.PP +In addition to the options common to all programs based on libnetpbm +(most notably \fB-quiet\fP, see +.UR index.html#commonoptions + Common Options +.UE +\&), \fBppmchange\fP recognizes the following +command line options: + + +.TP +\fB-closeness \fP\fIcloseness_percent\fP +\fIcloseness\fP is a percentage indicating how close to the color you +specified a pixel must be to get replaced. By default, it is 0, which means +the pixel must be the exact color you specified. +.sp +A pixel gets replaced if the distance in color between it and the +color you specified is less than or equal to \fIcloseness\fP per cent +of the maxval. +.sp +The "distance" in color is defined as the Cartesian sum of the +individual differences in red, green, and blue intensities between the +two pixels, normalized so that the difference between black and white +is 100%. +.sp +This is probably simpler than what you want most the time. You +probably would like to change colors that have similar chrominance, +regardless of their intensity. So if there's a red barn that is +variously shadowed, you want the entire barn changed. But because the +shadowing significantly changes the color according to +\fBppmchange\fP's distance formula, parts of the barn are probably +about as distant in color from other parts of the barn as they are +from green grass next to the barn. +.sp +Maybe \fBppmchange\fP will be enhanced some day to do chrominance +analysis. +.sp +This option was new in Netpbm 9.8 (September 2000). + +.TP +\fB-closeok\fP +This option affects how \fBppmchange\fP interprets a color you +specify in the arguments. When you specify this option, \fBppmchange\fP +may use a color close to, but not the same as what you specify. See +.UR #description +the description section +.UE +\& for details. +.sp +This option was new in Netpbm 10.22 (April 2004). Before that, +\fBppmchange\fP always behaved as if you specified this option. + +.TP +\fB-remainder \fP\fIcolor\fP +\fBppmchange\fP changes all pixels which are not of a color for +which you specify an explicit replacement color on the command line to +color \fIcolor\fP. +.sp +An example application of this is + +.nf +\fBppmchange -remainder=black red red\fP + +.fi + +to lift only the red portions from an image, or +.nf +\fBppmchange -remainder=black red white | ppmtopgm\fP + +.fi + +to create a mask file for the red portions of the image. + + + +.UN seealso +.SH SEE ALSO +.BR "pgmtoppm" (1)\c +\&, +.BR "ppmcolormask" (1)\c +\&, +.BR "ppm" (1)\c +\& + +.UN author +.SH AUTHOR + +Wilson H. Bent. Jr. (\fIwhb@usc.edu\fP) +with modifications by Alberto Accomazzi (\fIalberto@cfa.harvard.edu\fP) +.SH DOCUMENT SOURCE +This manual page was generated by the Netpbm tool 'makeman' from HTML +source. The master documentation is at +.IP +.B http://netpbm.sourceforge.net/doc/ppmchange.html +.PP
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