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.TH BLIND-SQUARE-GRADIENT 1 blind
.SH NAME
blind-square-gradient - Generate a video with a square gradient
.SH SYNOPSIS
.B blind-square-gradient
-w
.I width
-h
.I height
.SH DESCRIPTION
.B blind-square-gradient
prints a video with a square gradient to stdout,
parameters for each from is read from each frame
in stdin. The gradient is stored in all channels
of the video.
.P
The video in stdin must contain exactly 2 or 3
pixels per frame. The first pixel shall point to
the beginning of the gradient (where the value is
0) and the second pixel shall point to the end of
the gradient (where the value is 1). In these
pixels, the value of the first channel specifies
the X-position and the value of the second
channel specifies Y-position, the other channels
are ignored.
.P
If there is a third pixel, in frames in stdin,
the value of the second channel (the Y channel)
is used to modify the shape of the square, making
it rectangular; the other channels are ignored.
The axis perpendicular to the vector between
the beginning and end of the gradient is divided
by this value.
.SH NOTES
Pixels after the end of the gradient have values
larger than 1.
.BR blind-*-wave (1)
commands can be used to put all values between
0 and 1.
.SH OPTIONS
.TP
.BR -w " "\fIwidth\fP
The width of the video, in pixels.
.TP
.BR -h " "\fIheight\fP
The height of the video, in pixels.
.SH SEE ALSO
.BR blind (7),
.BR blind-from-text (7),
.BR blind-cone-gradient (1),
.BR blind-linear-gradient (1),
.BR blind-radial-gradient (1),
.BR blind-spiral-gradient (1),
.BR blind-double-sine-wave (1),
.BR blind-round-wave (1),
.BR blind-sawtooth-wave (1),
.BR blind-sinc-wave (1),
.BR blind-sine-wave (1),
.BR blind-triangular-wave (1),
.BR blind-spectrum (1)
.SH AUTHORS
Mattias Andrée
.RI < maandree@kth.se >
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