Chapter 4: Images.

• warping.cpp: Forward and backward image warping. You need the source image imagewarping.ppm. The results are: forwardwarping.ppm and backwardwarping.ppm.

• composite.cpp: Image compositing using alpha channel. You need the source image furrydog.ppm, the alpha matte furrydog-matte.ppm and the background image background.ppm The result is composite.ppm.

• zoneplate.cpp: Create a zone plate image to study resampling aliasing artefacts. The zone plate image is zoneplate.ppm.

• zoneplate2.cpp: Create another zone plate image to study resampling aliasing artefacts. The zone plate image is zoneplate2.ppm.

• discreteconvolution.cpp: A light implementation of a discrete convolution procedure using either the Laplacian or Identity kernel. You need the source image convolution-input.ppm. The result is convolution-result.ppm.

• colorcube.cpp: Display the RGB color cube in OpenGL(R). Here are two snapshots: snapshot1 PNG and snapshot2 PNG.

• errordiffusion.cpp: Various halftoning and dithering techniques. You need the source image "lena" lena.ppm.
  Here are the results: binary-threshold.ppm, binary-randomthreshold.ppm binary-diffusion.ppm, and tone-dither.ppm.