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100 points to know about...
Eco-Design Web Development

100
points to know about...
Eco-Design Web Development
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Notion 50

Understand image compression.

Target skills

Familiarise yourself with image compression and some tools for it.

In this module, we will discuss the principle of image compression on the web.

Image compression is a process that consists of reducing the weight of data without deteriorating the quality of the image. In other words, it eliminates the repetition of data in an image so that it can be stored without taking up much space and/or transmitted quickly.

There are two types of image compression:

  • the method known as "without loss": makes it possible to restore the image with the identical one of the original;
  • the method known as "with loss": makes it possible to reduce the color space to the most current colors of an image. The chosen colors are indicated in the color palette located in the header of the compressed image.

Here is a non-exhaustive list of tools recommended for compressing different web image formats.

JPEG format

  • Apowersoft Image Compressor available online, allows to convert files without limitation of number or size. Here is the link to access it: http://www.apowersoft.fr
  • JPEG COMPRESSOR is also available online and proposed in different languages, but downloadable files are limited to 20. Here is the link to access it: http://www.compressjpeg.com
  • TinyJPG is an application that allows you to reduce the size of your files by up to 70%. Here is the link to access it: http://tinyjpg.com

GIF format
Compression tools for the GIF format are available for free online and can reduce the file size by 50% or more. They optimize the GIF file size to save disk space.

  • GIF Optimizer
  • File Optimizer
  • Compressor.io

PNG format