pngcomp - PNG (Portable Network Graphics) comparison tool

       pngcomp was written by Stuart Coyle <stuart@cybertherial.com>.

       This manual page was written by Nelson A. de Oliveira <naoliv@gmail.com>, for the Debian project (but may
       be used by others).

                                         Sat, 08 Jul 2006 00:54:16 -0300                              PNGCOMP(1)

pngcomp  gives some basic statistics about the difference between two images. It was created as a measure
       of various color quantization methods.

       pngcomp - PNG (Portable Network Graphics) comparison tool

       The stats created by this program are purely based on the Euclidean distance in RGBA  space  between  the
       pixels of the images. Later versions will include different measures such as CIE color space measurements
       and filters for perception models.

       The error calculation used reflects the perceived quality of images only roughly.

       To determine what image is better nothing can surpass having a look for yourself!

-v     Verbose, does nothing as yet.

       -V     Version, prints version information.

       -h     Help, prints this message.

pngcomp [-vVh] image1.png image2.png