term% cat index.txt LERP(9.1) LERP(9.1)
NAME
lerp, sub - linear combinations of images
SYNOPSIS
fb/lerp file fraction [ file fraction ... ]
fb/sub file1 file2
DESCRIPTION
Lerp computes a linear combination of a number of input images. Each
input file name is followed by a floating-point fraction by which to
scale its pixel values. The fraction after the last image may be omit‐
ted, in which case one minus the sum of the other fractions is used.
The resulting image is written to standard output.
Nothing prevents the fractions from being smaller than zero or larger
than one. Output pixel values that fall below zero or above 255 are
clamped.
Sub reads two images, which must be the same size and have the same
number of channels. Each channel of each pixel of the output image is
the absolute value of the difference between the corresponding input
values.
SOURCE
/sys/src/fb/lerp.c
/sys/src/fb/sub.c
SEE ALSO
picfile(9.6)
LERP(9.1)