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List of file formats: Difference between revisions
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mention that RLE is lossless
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These files are texture files in [http://en.wikipedia.org/wiki/Silicon_Graphics SGI] Image Format. This format supports multiple layers, transparency, compression, indexed colors, 8 bits and 16 bits per plane. Files of this format use different extensions, often to indicate the image properties, but in fact it's always the same format. The "official" extensions is <tt>*.sgi</tt>. Images with one layer are usually black/white (<tt>*.bw</tt>) or a mere alpha layer (<tt>*.a</tt>), with two layers black/white with alpha, with three layers red/green/blue (<tt>*.rgb</tt>), and with four layers red/green/blue/alpha (<tt>*.rgba</tt>). This, however, is a convention and not mandated by the image specification. SGI images can be [http://en.wikipedia.org/wiki/Run-length_encoding RLE-compressed] | These files are texture files in [http://en.wikipedia.org/wiki/Silicon_Graphics SGI] Image Format. This format supports multiple layers, transparency, compression, indexed colors, 8 bits and 16 bits per plane. Files of this format use different extensions, often to indicate the image properties, but in fact it's always the same format. The "official" extensions is <tt>*.sgi</tt>. Images with one layer are usually black/white (<tt>*.bw</tt>) or a mere alpha layer (<tt>*.a</tt>), with two layers black/white with alpha, with three layers red/green/blue (<tt>*.rgb</tt>), and with four layers red/green/blue/alpha (<tt>*.rgba</tt>). This, however, is a convention and not mandated by the image specification. SGI images can be uncompressed or [http://en.wikipedia.org/wiki/Run-length_encoding RLE-compressed], which is a lossless compression method. | ||
FlightGear uses [http://plib.sourceforge.net/ plib] to read SGI images. They must not use 16 bits per plane and have to have side lengths of 2<sup>n</sup>x2<sup>m</sup>. For example: 64x64, 256x256 or 128x2048. Note that other sizes will '''not''' work, and let FlightGear use a red/white chequer texture instead! FlightGear textures ''shall'' be RLE-compressed, and as 'aggressively' as possible. | FlightGear uses [http://plib.sourceforge.net/ plib] to read SGI images. They must not use 16 bits per plane and have to have side lengths of 2<sup>n</sup>x2<sup>m</sup>. For example: 64x64, 256x256 or 128x2048. Note that other sizes will '''not''' work, and let FlightGear use a red/white chequer texture instead! FlightGear textures ''shall'' be RLE-compressed, and as 'aggressively' as possible. | ||