PNG image tools for MS Windows
IrfanView - FREEWARE
IrfanView is an image viewer / converter which can read and display over 70 image formats, including digital camera formats. It can write 16 formats, including JPEG, GIF, PNG, and Windows BMP. It's free for non-commercial use.
IrfanView provides very good compression for converting GIFs larger than 2k bytes and for 24 bit PNG images ( user option: compression level 9 ).
The latest version includes Ken Silverman's PNGOUT compression tool among its plugins. It will produce smaller PNG files than the standard implementation.
There is also the option to set a transparent color in PNG files. If the source file is 24 bit color, and a transparent color is chosen, the resulting PNG file will contain a "tRNS" chunk, which pre-IE7 Internet Explorer versions ignore except in palette images. It is best to reduce 24 bit images to a palette of 256 colors before saving them with transparency.
IrfanView's user-interface (GUI) is configurable, and the window automatically resizes to the dimensions of an image. IrfanView has an Effects menu and a Hex Viewer which can open any file type. Many free plug-ins are available, including a MNG player. The website is in English and German:
PNGOUT uses a compression engine that can almost always create smaller files than standard PNG implementations. It can also convert GIF, BMP, JPG, and other formats as indicated in the "Select files" dialog box. Two commercial applications are available for power users: PNGOUTWin for single files and batch processing ( 30 day trial ), and a PNGOUT Plugin for Adobe Photoshop ( 15 day trial ). For more information visit:
PNGOUT is also available as a free command line utility. It can convert GIF, BMP, JPG, TGA and PCX images to PNG format. Some visitors may already be familiar with the pngcrush command line utility. PNGOUT can produce smaller files than pngcrush -brute. There is a Linux version also. Visit Ken Silverman's Utility Page.
Web Image Guru
Web Image Guru is an image converter which can run as a standalone application or as an external module for well known image editors:
Web Image Guru provides excellent compression for PNG images. It is also hard to beat for JPEG compression. In addition, it can output images as GIF and WBMP - Wireless Bitmap - the format for older types of mobile phone. With Web Image Guru you can apply PNG filtering options.
The screenshot shows the options panel. The Web Image Guru interface also has a panel showing the original image and a preview panel showing the results of the chosen options. As well as providing color palette editing, Web Image Guru can change the background color of PNG alpha images. Information about Web Image Guru ( 14 days free trial ) and other Vimas products can be found at:
Tweak PNG - FREE
If you are familiar with the internal format of PNG files this utility will enable you to add, modify or delete the building blocks within a file (referred to as "chunks"). Text annotations can be added using the "tEXt" chunk, and background colors can be added using the "bKGD" chunk (screenshots). Pre-IE7 Internet Explorer versions don't directly support alpha transparency, so adding a background color can ensure that the image background matches the background color of the page. Otherwise pre-IE7 versions set a gray-ish background by default.
First, here is an example of a 24 bit PNG image containing 256 colors. The file size is 596 bytes. Convert it to GIF format using the best optimizer you can find. The GIF file will still end up more than 20 times the size of the PNG file! The conversion tests in the chart below used more typical images -- optimized GIF versions of 24 other images from this site. Web Image Guru is compatible with Windows 98/NT4/2000/ME/XP. IrfanView is also compatible with Windows95.
png2ico - favicon utility - FREE
png2ico uses PNG images to create a "favicon.ico" file containing one or more internal images with 2, 16 or 256 colors. A favorites icon usually contains a logo at resolutions 16x16 and 32x32, although a single 16x16 image can be used for all requirements. If the file is named "favicon.ico", and is placed in the domain's root directory, there is no need to use <LINK> tags.
|PNG Image tools||IrfanView||Web Image Guru||Paint Shop Pro|
|PNG file size savings:||With the PNGOUT|
plugin it will
surpass the rest.
|GIFs over 2k||46%||54%||46%|
|GIFs under 2k||increased||13%||7%|
|24 bit PNG files|
|User selectable options:|
|8-bit, 24-bit, grayscale||Auto 8/24||YES||YES|
|Transparency (1|alpha)||One color||YES||YES|