MozJPEG improves JPEG compression efficiency achieving higher visual quality and smaller file sizes at the same time. It is compatible the JPEG standard, and the vast majority of the world’s deployed JPEG decoders.
MozJPEG is a patch for libjpeg-turbo. MozJPEG is binary-compatible with both libjpeg-turbo and the classic libjpeg. This makes it possible to use MozJPEG as a drop-in replacement for libjpeg, and even install it as a system-wide replacement.
This is free and open source software.
Key Features
- Progressive encoding with “jpegrescan” optimization. It can be applied to any JPEG file (with jpegtran) to losslessly reduce file size. Parameters of progressive JPEG passes influence compression, so it’s possible to make smaller files by tuning them.
- Trellis quantization. When converting other formats to JPEG it maximizes quality/filesize ratio. Simple JPEG encoders discard a fixed amount of detail according to quality set, but MozJPEG looks how many bits it would cost to write each detail and discards details that compress the least. This makes files much smaller, but also tends to make images look softer (which, depending on an image, may be a good or a bad thing).
- Cleaner black-on-white text and lines.
- Smoother high-DPI “compressive” images.
- Comes with new quantization table presets, e.g. tuned for high-resolution displays.
- Fully compatible with all web browsers.
- Can be seamlessly integrated into any program that uses the industry-standard libjpeg API. There’s no need to write any MozJPEG-specific integration code.
Website: github.com/mozilla/mozjpeg
Support: Photo Compression
Developer: Mozilla (MozJJPEG is a patch for libjpeg-turbo)
License: Custom BSD-like licenses
MozJPEG is written in C and Assembly. Learn C with our recommended free books and free tutorials. Learn Assembly with our recommended free books and free tutorials.
Related Software
| Console Based Image Compression Tools | |
|---|---|
| MozJPEG | Mozilla JPEG Encoder Project |
| pngquant | Utility and a library for lossy compression of PNG images |
| SVGO | Node.js library and command-line application for optimizing SVG files |
| Oxipng | Multithreaded PNG optimizer, forked from Optipng |
| libjxl | Reference implementation of JPEG XL |
| libjpeg-turbo | JPEG image codec |
| QOI | The Quite OK Image Format |
| YOGA | Yummy Optimizer for Gorgeous Assets |
| pngcrush | Optimizer for PNG files |
| jpegoptim | Optimize JPEG files. Lossless and lossy compression available |
| OptiPNG | Advanced PNG optimizer |
| Guetzli | Perceptual JPEG encoder with excellent compression density at high quality |
| ECT | Fast and effective C++ file optimizer |
| Crunch | Lossy PNG image file optimization |
| zopflipng | PNG optimisation tool using zopfli |
| JPEG Archive | Utilities for archive JPEGs for long term storage |
| optimizt | CLI image optimization tool |
| picopt | Multi format lossless image optimize |
| tinifier | CLI tool for compressing images using the TinyPNG API |
Read our verdict in the software roundup.
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