ANI is a graphics file format defined by Microsoft for simple animated icons and cursors on its Windows operating system.

The format is based on the Microsoft RIFF file format, which is used as a container for a number of icons or cursors that conform to the ICO format.

Contents

Animated cursors contain the following information (in order of position in file):

• Name. Optional cursor name information.
• Artist. Optional artist information.
• Default Frame Rate. Defines the default frame rate. Required even if individual frame rates are used.
• Sequence Information. See Sequence Information below.
• Hotspot. Since a cursor is 32x32, there needs to be a defined 'hotspot', such as 16x16 (the centre).
• Frame(s). At least one frame, in ICO format.
• Individual Frame Rates. Optional frame rates for each icon.

Frames rates are measured in jiffies, with one jiffy equal to 1/60 of a second, or 16.666 ms.

Sequence Information

Sequence information allows frames to be played more than once, and in a different order than how they are saved in the file.

For example, if you have three icons in your animated cursor (1, 2, 3), you could have a sequence that is 1-2-3-2-1, and you would only need to have each icon once. This saves space and is neater.

External links

• Description of the ani file format

Computer file formats | Microsoft