A simple script using the http://pi-xel.io filtering method to improve JPEG file compression using precompiled binary for Linux 32 bits.

Usage: ./jpegfilter.sh options
Options:
     -q Output JPEG quality, default 95
     -f input file
     -m Filtering method, default 1
        1 - apply high quality adaptive focus filtering on the full RGB image
        2 - apply high quality adaptive focus filtering on Y, and low quality filters to UV
        3 - apply no filtering on Y, and low quality filters to UV

The script create a file prefixed with pf_ of the original name

E.g. for batch processing

for P in `ls test*.jpg`
do 
    ./jpegfilter.sh -q 95 -m 3 -f $P
done

Parameters:

• m 1 and 2 are slighty loosy but preserve image details - producing more compression
• m 3 is unnoticible lossy - producing less compression

Results:

• Original size: 2848kB
• m 1 param: 2568kB (90%)
• m 2 param: 2460kB (86%)
• m 3 param: 2700kB (95%)