MobileRead Forums - View Single Post - Which JPEG compresion algorithms in ebook editor?

Francois_C · 04-09-2017, 06:47 AM

I love the ebook editor and I use it daily, but, just out of curiosity I would like to know which algorithms are used in JPEG lossless compression of covers and images.

I get better results (about 6%) with it than with Timo Kokkonen's jpegoptim, which strips metadata and optimizes Huffman tables for lossless compression.

Are you using wavelet compression? I heard about applying some sort of JP2000 algorithm on JPEG files.

04-09-2017, 06:47 AM	#1
Francois_C Zealot Posts: 106 Karma: 8300 Join Date: Jul 2012 Location: France Device: Kobo Aura H2O, Kobo Touch, Kobo Mini	Which JPEG compresion algorithms in ebook editor? I love the ebook editor and I use it daily, but, just out of curiosity I would like to know which algorithms are used in JPEG lossless compression of covers and images. I get better results (about 6%) with it than with Timo Kokkonen's jpegoptim, which strips metadata and optimizes Huffman tables for lossless compression. Are you using wavelet compression? I heard about applying some sort of JP2000 algorithm on JPEG files. Last edited by Francois_C; 04-09-2017 at 06:55 AM.