ppmspread
Randomly displace pixels for noise effect
TLDR
Spread pixels randomly
$ ppmspread [amount] [input.ppm] > [output.ppm]
Light spread effect$ ppmspread 5 [input.ppm] > [output.ppm]
Heavy spread effect$ ppmspread 20 [input.ppm] > [output.ppm]
SYNOPSIS
ppmspread amount [file]
DESCRIPTION
ppmspread randomly displaces each pixel in a PPM image to a new position within the specified radius, creating a scattered, noise-like blur effect. Larger spread amounts produce more diffuse results while small amounts add subtle texture.Unlike Gaussian blur which averages pixels, spread preserves individual pixel colors but randomizes their positions, producing a distinctive frosted glass or pointillist appearance. Part of the Netpbm toolkit.
PARAMETERS
AMOUNT
Spread radius in pixels.FILE
Input PPM file.
INSTALL
sudo apt install netpbm
sudo dnf install netpbm
sudo pacman -S netpbm
sudo apk add netpbm
sudo zypper install netpbm
brew install netpbm
nix profile install nixpkgs#netpbm
CAVEATS
Only accepts PPM format input. Use pnmtoppm to convert from other formats first. The amount parameter specifies the maximum displacement in any direction; actual displacement for each pixel is random within that range.