From 058b0118a52061ad57694c01fc8763b22b789c4d Mon Sep 17 00:00:00 2001 From: rsc Date: Mon, 3 Jan 2005 06:40:20 +0000 Subject: Some man pages. --- man/man1/crop.1 | 147 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 147 insertions(+) create mode 100644 man/man1/crop.1 (limited to 'man/man1/crop.1') diff --git a/man/man1/crop.1 b/man/man1/crop.1 new file mode 100644 index 00000000..2804ece0 --- /dev/null +++ b/man/man1/crop.1 @@ -0,0 +1,147 @@ +.TH CROP 1 +.SH NAME +crop, iconv \- frame, crop, and convert image +.SH SYNOPSIS +.B crop +[ +.BI -c +.I red +.I green +.I blue +] +[ +.B -i +.I n +| +.B -x +.I dx +| +.B -y +.I dy +| +.B -r +.I minx +.I miny +.I maxx +.I maxy +] +[ +.B -t +.I tx +.I ty +] +[ +.B -b +.I red +.I green +.I blue +] +[ +.I file +] +.PP +.B iconv +[ +.B -u +] [ +.B -c +.I chandesc +] +[ +.I file +] +.SH DESCRIPTION +.I Crop +reads an +.IR image (7) +file (default standard input), crops it, and writes it as a compressed +.IR image (7) +file to standard output. +There are two ways to specify a crop, by color value or by geometry. +They may be combined in a single run of +.IR crop , +in which case the color value crop will be done first. +.PP +The +.B -c +option takes a red-green-blue triplet as described in +.IR color (3). +(For example, white +is +.B 255 +.B 255 +.BR 255 .) +The corresponding color is used as a value to be cut from the outer +edge of the picture; that is, the image is cropped to remove the maximal +outside rectangular strip in which every pixel has the specified color. +.PP +The +.B -i +option insets the image rectangle by a constant amount, +.IR n , +which may be negative to generate extra space around the image. +The +.B -x +and +.B -y +options are similar, but apply only to the +.I x +or +.I y +coordinates of the image. +.PP +The +.B -r +option specifies an exact rectangle. +.PP +The +.B -t +option specifies that the image's coordinate system should +be translated by +.IR tx , +.IR ty +as the last step of processing. +.PP +The +.B -b +option specifies a background color to be used to fill around the image +if the cropped image is larger than the original, such as if the +.B -i +option is given a negative argument. +This can be used to draw a monochrome frame around the image. +The default color is black. +.PP +.I Iconv +changes the format of pixels in the image +.I file +(default standard input) and writes the resulting image to standard output. +Pixels in the image are converted according to the channel descriptor +.IR chandesc , +(see +.IR image (7)). +For example, to convert a 4-bit-per-pixel grey-scale image to an 8-bit-per-pixel +color-mapped image, +.I chandesc +should be +.BR m8 . +If +.I chandesc +is not given, the format is unchanged. +The output image is by default compressed; the +.B -u +option turns off the compression. +.SH EXAMPLE +To crop white edges off the picture and add a ten-pixel pink border, +.IP +.EX +crop -c 255 255 255 -i -10 -b 255 150 150 imagefile > cropped +.EE +.SH SOURCE +.B /usr/local/plan9/src/cmd/draw/crop.c +.SH SEE ALSO +.IR image (7), +.IR color (3) +.SH BUGS +.I Iconv +should be able to do Floyd-Steinberg error diffusion or dithering +when converting to small image depths. -- cgit v1.2.3