OptiPNG
| OptiPNG
|
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|---|---|
 The command line output when attempting to shrink a file without success |
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| Basic data
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| developer | Cosmin Truţa |
| Current version |
0.7.7 ( December 27, 2018 ) |
| operating system | Unix-like , Windows |
| programming language | C. |
| category | Image optimizer |
| License | zlib / libpng license |
| German speaking | No |
| optipng.sourceforge.net | |
OptiPNG is a free command line program to raster graphics in PNG format to compress lossless . It can also check the integrity of PNG files, restore metadata , and convert other raster graphic formats ( BMP , GIF , TIFF , PNM ) to PNG.
As a further development of pngcrush , OptiPNG also optimizes the deflate compression of the IDAT blocks, which contain the actual image data, by trying out various pre-filters and parameters of the compression process. PNG files, which most of the common image editing programs do not generate optimized for this, can usually be reduced in size significantly without falsifying the image information (see lossless compression ).
In addition, particularly effective lossy compression methods can be selected with which the color model , color palettes and bit depths can be changed without additional processing steps or programs such as pngrewrite.
OptiPNG is developed in the C programming language and published as free software under the zlib / libpng license .
The first version (version 0.0) was published on December 10, 2001.
It is used, among other things, by Google Page Speed , an extension for Mozilla -based web browsers to optimize website performance.
There is now a modified version called rOptiPng, which can also recursively handle files from several directories at once.
For Macs with Mac OS X Snow Leopard 10.6 and Intel processors, the graphic user interface PNGPress for OptiPNG is now available.
For computers with Windows (98, 2000, XP, Server 2003, Vista, 7) the graphical user interface OptiPNG-UI is available, which already contains the command line program.
For Freeware - imaging software Paint.NET one is plugin available that enables the compressed storage.