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      <FormatDescription>True Colour Sprites files are part of raster image graphics associated with Spooky Sprites, a graphics editor for Atari Falcon. This particular record identifies True Colour Sprites files that were compressed using Packed-Ice, a file compression tool used on Atari computers. Packed-Ice was developed by pseudonym "Axe of Delight", later changed to "Axe of Superior". There are several different versions of this compression tool. The files compressed using Packed-Ice program, start with ASCII "Ice!", or "ICE!", followed by a gap between 4-11 characters and then the magic bytes of the original file format. 

The Atari Falcon030 (usually shortened to Atari Falcon), released in 1992, was the final personal computer product from Atari Corporation. A high-end model of the Atari ST line, the machine is based on a Motorola 68030 CPU and a Motorola 56000 digital signal processor, a feature which distinguishes it from most other microcomputers of the era. It included a VIDEL programmable graphics system which greatly improved graphics capabilities.</FormatDescription>
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      <ProvenanceSourceID>180</ProvenanceSourceID>
      <ProvenanceName>The National Archives and Records Administration / The National Archives and Records Administration</ProvenanceName>
      <ProvenanceSourceDate>24 Jan 2022</ProvenanceSourceDate>
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      <LastUpdatedDate>24 Jan 2022</LastUpdatedDate>
      <FormatNote>http://fileformats.archiveteam.org/wiki/Spooky_Sprites

http://fileformats.archiveteam.org/wiki/Pack-Ice

https://mikro.naprvyraz.sk/docs/Coding/1/PACKING.TXT

https://en.wikipedia.org/wiki/Atari_Falcon</FormatNote>
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        <SignatureID>1941</SignatureID>
        <SignatureName>Packed-Ice True Colour Sprites [Spooky Sprites] (Atari Falcon)</SignatureName>
        <SignatureNote>BOF; Offset: 0; Magic Bytes: 'ICE! {4-11} TCSF'</SignatureNote>
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          <ByteSequenceValue>49434521{4-11}54435346</ByteSequenceValue>
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        <Description>Run length encoding (RLE) is perhaps the simplest image compression technique in common use. RLE algorithms are lossless, and work by searching for runs of bits, bytes, or pixels of the same value, and encoding the length and value of the run. As such, RLE achieves best results with images containing large areas of contiguous colour, and especially monochrome images. Complex colour images, such as photographs, do not compress well – in some cases, RLE can actually increase the file size. There are a number of RLE variants in common use, which are encountered in the TIFF, PCX and BMP graphics formats.</Description>
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