Image Compression Benchmarks

This compression ratio tests are implemented on compressors:

• libjpeg-turbo-1.5.1
• mozjpeg-3.2
• guetzli-1.0.1
• guetzli then mozjpeg

with 2 image set:

• CMS images.
• product images.

Notes:

• libjpeg/ mozjpeg are lossless compression.
• guetzli is lossy compression with default parameters, means butteraugli score ~ 0.97.

Prerequisites

• ./install.sh
• ./do_mozjpeg_tests.sh
• ./do_guetzli_tests.sh
• ./guetzli_then_mozjpeg.sh
• ./compare.sh

Results

CMS images

• Artifacts: 113 images (inputs/cms).
• Low/ medium quality.

Image type	Size	Compare to inputs
inputs	4093 kB	0%
libjpeg	3876 kB	-5% smaller
mozjpeg	3716 kB	-9% smaller
guetzli	2672 kB	-34% smaller
guetzli_then_mozjpeg	2582 kB	-36% smaller

Product images

• Artifacts: 493 images (inputs/products).
• Good quality.

Image type	Size	Compare to inputs
inputs	79925 kB	0%
libjpeg	60094 kB	-24% smaller
mozjpeg	55325 kB	-30% smaller
guetzli	43703 kB	-45% smaller
guetzli_then_mozjpeg	40172 kB	-49% smaller

Conclusions

• mozjpeg is 4.13% - 8% better than libjpeg.
• The output of guetzli looks good, can't see the difference with human eyes.
• The compression time of guetzli is extremely slow (On a c4.2xlarge instance, guetzli compression on 493 product images takes 66 minutes).