Optics principles. For example, the Ames room, Hering, Müller-Lyer, Orbison, Ponzo, Sander, and Wundt illusions all rely on the suggestion of the appearance of distance by using converging and diverging lines, in the same way that parallel light rays (or indeed any set of parallel lines) appear to converge at a vanishing point at infinity in two-dimensionally rendered images with artistic perspective. This suggestion is also responsible for the famous moon illusion where the moon, despite having essentially the same angular size, appears much larger near the horizon than it does at zenith. This illusion so confounded Ptolemy that he incorrectly
Microsoft Point-to-Point Compression achieves higher compression ratios when 8:1 isn't achievable. Microsoft Point-to-Point Compression Microsoft Point-to-Point Compression (MPPC; described in RFC 2118) is a streaming data compression algorithm based on an implementation of Lempel–Ziv using a sliding window buffer. According to Hifn's IP statement, MPPC was patent-encumbered (last US patent granted on 1996-07-02). Where V.44 or V.42bis operate at layer 1 on the OSI model, MPPC operates on layer 2, giving it a significant advantage in terms of computing resources available to it. The dialup modem's in-built compression (V.44 or V.42bis) can only occur after the data has been serially transmitted to the