ppmshadow
Add drop shadow effect to PPM images
TLDR
SYNOPSIS
ppmshadow [options] [file]
DESCRIPTION
ppmshadow adds a drop shadow effect to a PPM image, creating the appearance of the image floating above a background. The shadow is created by blurring a darkened copy of the image and placing it offset behind the original.The blur radius controls shadow softness, while x and y offsets control the apparent light direction. The -t option creates a translucent shadow that allows the background to show through. Part of the Netpbm toolkit.The input image must have a transparent (black) background area for the shadow to be visible. The output image is larger than the input by the shadow offset.
PARAMETERS
FILE
Input PPM file. Reads from stdin if omitted.-b N
Blur radius controlling shadow softness (default: 11).-x N
Horizontal shadow offset in pixels (default: blur radius / 2).-y N
Vertical shadow offset in pixels (default: same as -x).-t
Create a translucent shadow instead of a solid black one.
CAVEATS
Requires the image to have a transparent (black) background around the subject for the shadow to appear correctly. Internally uses pnmconvol for blurring, which can be slow for large blur radii. Part of the Netpbm suite.
HISTORY
ppmshadow was created by John Walker as part of the Netpbm toolkit for image shadow effect generation.
