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*Details: File format summary



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Name GEM Image
Other names  
Identifiers PUID:  x-fmt/159
Classification Image (Raster)
Description The GEM raster format (also known as GEM VDI Bit Image; GEM Bit Image; GEM Image; GEM Bitmap; or IMG) is an image format native to the Graphical Environment Manager (GEM) operating system and developed at Digital Research. The format was used by GEM Paint and Ventura Publisher, and by a variety of Atari ST software. GEM raster images may be color, gray scale, or black and white and are always read and written in the big-endian format. The format of bi-level images is well standardized, but the specification is ambiguous as to the format of color images. As a result, other color formats of GEM raster image were later developed, some of which have their own names, such as XIMG (Extended GEM Bit Image), TIMG (TrueColor IMG), STTT, or Hyperpaint.
Orientation Text
Byte order Big-endian (Motorola)
Related file formats Is previous version of XIMG (Extended GEM Bit Image)  
Technical Environment  
Supported until  
Format Risk  
Developed by None.
Supported by None.
Source Digital Preservation Department / The National Archives
Source date 02 Aug 2005
Source description  
Last updated 29 Mar 2022
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