"Jpegpixi" is short for "JPEG pixel interpolator". It is a command-line utility which interpolates pixels in JFIF images (commonly refered to as "JPEG images"). This is useful to correct images from a digital camera with CCD defects. Jpegpixi is unique in that it tries to preserve the quality of the JFIF image as much as possible. Most graphics programs decode JFIF images when they are loaded, and re-encode them when they are saved, which results in an overall loss of quality. Jpegpixi, on the other hand, does not decode and re-encode the image, but manipulates the encoded image data, protecting the quality of the image as much as possible.
Opag, which stands for "Option Parser Generator", is a program to generate C or C++ code which parses command line options. It takes as input a description of the command line options you want your program to support. The output is a C or C++ function which finds these options in an array of strings (typically "argv", the second parameter of the "main" function) and sets variables accordingly. Short (single character) as well as long (GNU style) options are supported. It is also possbile to associate a help string with each option. Opag uses these to create a macro which expands to a string containing a nicely formatted description of the options.