BBOX(9.1) BBOX(9.1)
NAME
bbox - compute bounding rectangle
SYNOPSIS
fb/bbox [ -s ] [ -cchannel ] [ -vvalue ] [ picture ]
DESCRIPTION
Bbox reads the given picture file (default standard input)
and prints on its standard output the minimum bounding box
of the interesting pixels of the image. `Interesting' pix-
els are those for which a given channel, specified by the -c
option, does not have a given value, specified by the -v
option. -v defaults to 0, and -c defaults to the α channel
(letter 'a' in the CHAN= header line) if the image contains
one, or the `m' channel otherwise. If the image has neither
α nor `m', option -c is not optional. By default, there-
fore, bbox prints the bounding box of the visible parts of
an image with an α channel, or the non-black parts of a
monochrome image.
Option -s causes bbox to instead copy its input to standard
output, clipping the image to the bounding rectangle.
SOURCE
/sys/src/fb/bbox.c
SEE ALSO
picfile(9.6)
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