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.