On Tue, Aug 09, 2011 at 03:16:34PM +0200, Philipp Klaus Krause wrote: > Am 09.08.2011 13:10, schrieb Rudolf Polzer: > > As for compression: the compressed format is basically "each 4x4 block is a > > 2-color optimum palette image". Similar schemes have existed way before S3TC > > […] > > See Beers et al., "Rendering from compressed textures" in the SIGGRAPH > '96 proceedings for the AFAIK first use of this technique in texture > compression.
Graham Campbell, Thomas A. DeFanti, Jeff Frederiksen, Stephen A. Joyce, and Lawrence A. Leske. 1986. Two bit/pixel full color encoding. SIGGRAPH Comput. Graph. 20, 4 (August 1986), 215-223. describes a scheme that is VERY similar, except that that scheme additionally uses a global palette for the two colors of the blocks, while "S2TC" stores the two reference colors in the blocks directly. They achieve twice the compression ratio that way. Best regards, Rudolf Polzer _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev