Raster and serpentine error diffusion halftone

Error diffusion halftone using the standard Floyd-Steinberg's algorithm (both raster and serpentine)

Simple error diffusion halftone implementation using the standard Floyd-Steinberg's algorithm for grayscale images, with both raster and serpentine parse provided.
Image files are first converted from sRGB to linear RGB values, this step is optional.

By Zong Qin ([e-mail]) from National Chiao Tung University, Taiwan.

*In-file functions and rgb2lin cannot be supported by old-version Matlab.