"Jpegpixi" is short for "JPEG pixel interpolator". The intent of the program is to interpolate pixels in JFIF images (commonly referred to as "JPEG images"). This is useful to correct images from a digital camera with CCD defects. For example, if one pixel is always bright green, this pixel can be interpolated away with jpegpixi.

Jpegpixi is unique in that it tries to preserve the quality of the JFIF image as much as possible. Usual 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 (known as the "discrete cosine transformation coefficients"). Therefore, the blocks (typically 8x8, 8x16, or 16x16 pixel areas) which contain the pixels to be interpolated are minimally disturbed, and other blocks remain pixel-by-pixel identical to the original image.

Jpegpixi is a command line utility.