Jpegpixi

Jpegpixi is a software tool that can be used to interpolate pixels in JPEG images. The name comes from the combination of the words JPEG and Pixel Interpolator. This program is especially useful for correcting images from a digital camera that have CCD defects. For instance, if some single pixels, dots, or stripes are always bright green, they can be corrected by interpolating them with jpegpixi.

One of the most unique features of jpegpixi is that it tries to preserve the quality of the JPEG image to the greatest extent possible. Traditional graphics programs typically decode JPEG images when they are loaded and re-encode them when they are saved, resulting in a loss of quality. With jpegpixi, only the DCT blocks (the typical sizes being 8×8, 16×8, or 16×16 pixel areas) that contain the pixels to be interpolated are decoded. When re-encoding them, encoding parameters identical to those used in the original image are utilized. As a result, only those blocks containing interpolated pixels are marginally affected, while other blocks remain unchanged and identical to those of the original image.

Jpegpixi is a command-line utility that comes with manual pages available in four languages, namely English, Finnish (thanks to Jarno Elonen), French (thanks to Stephan Peccini), and German. The software is released under the GNU General Public License, and it offers the user a lot of flexibility as well as being free.

The latest release of jpegpixi has fixed a typo in the English manual page and updated the postal address of the Free Software Foundation. Overall, this software is indeed a valuable tool in helping users with pixel interpolation in JPEG images, while at the same time retaining the quality of the original JPEG.