jpegjudge

JPEGJUDGE(1)                General Commands Manual               JPEGJUDGE(1)



NAME
       jpegjudge - guess jpeg picture quality

SYNOPSIS
       jpegjudge [ -V ]

       jpegjudge [ -b ] file ...

DESCRIPTION
       Jpegjudge reads each argument and attempts to guess the quality with
       which it was saved. Currently, only a rough indicator is calculcated,
       ranging from 0 (lowest quality) to 1000 (highest quality), an extension
       to other formats would be straightforward, but isn't planned.

       It can read all pictures the IJG jpeg library can read, i.e. normal and
       progressive jpeg's.

   OPTIONS
       -b     Display only quality indicator, suppress other information
              (filenames).

       -h, --help
              Display short summary of options.

       -V, --version
              Display version number and exit.

BUGS
       It should be possible to judge pictures stored in non-lossy formats,
       too, since conversion to jpeg may influence the measurement.

       The quality indicator is non-linear, and could be much better.

       The algorithm to calculate the quality was made up in 10 minutes, after
       staring at various histograms.

ACKNOWLEDGEMENTS
       This program contains code from the IJG jpeg software.




                    Jpegjudge - guess jpeg picture quality        JPEGJUDGE(1)