| Format introduction | The ICO file format is an image file format for computer icons in Microsoft Windows. ICO files contain one or more small images at multiple sizes and color depths, such that they may be scaled appropriately. In Windows, all executables that display an icon to the user, on the desktop, in the Start Menu, or in Windows Explorer, must carry the icon in ICO format. | Truevision TGA, often referred to as TARGA, is a raster graphics file format created by Truevision Inc. It was the native format of TARGA and VISTA boards, which were the first graphic cards for IBM-compatible PCs to support Highcolor/truecolor display. |
| Technical details | An ICO file is made up of an ICONDIR ("Icon directory") structure, containing an ICONDIRENTRY structure for each image in the file, followed by a contiguous block of all image bitmap data (which may be in either Windows BMP format, excluding the BITMAPFILEHEADER structure, or in PNG format, stored in its entirety). | The format can store image data with the maximum 24 bits of RGB and an extra 8-bit alpha channel. Color data can be color-mapped, or in direct color or truecolor format. Image data may be stored raw, or optionally, a lossless RLE compression similar to PackBits can be employed. |
| File extension | .ico | .tga |
| MIME | image/x-icon, image/vnd.microsoft.icon | image/x-targa, image/x-tga |
| Developed by | Microsoft | Truevision |
| Type of format | Graphics file format for computer icons | Raster image file |
| Associated programs | Axialis IconWorkshop, IcoFX, IconBuilder, Microangelo Toolset, Greenfish Icon Editor Pro, GIMP, ImageMagick, IrfanView, ResEdit. | Adobe Photoshop, Corel's Photo-Paint and Paint Shop Pro, the GIMP, GraphicConverter, Helicon Filter, ImageMagick, Inkscape, IrfanView, Pixel image editor, Paint.NET and Xara Photo & Graphic Designer and many others. |
| Wiki | https://en.wikipedia.org/wiki/ICO_(file_format) | https://en.wikipedia.org/wiki/Truevision_TGA |