Another major difference, with JPEG, their visual artifacts: JPEG 2000 only produces ringing artifacts, manifested as blur and rings near edges in the image, while JPEG produces both ringing artifacts and ‘blocking’ artifacts, due to its 8×8 blocks. But they need to be complex and computationally demanding. However, as a result of this flexibility, JPEG 2000 requires encoders/decoders. By ordering the codestream in various ways, applications can achieve significant performance increases. What does it mean? It means that it can be decoded in a number of ways for example, by truncating the codestream at any point, one may obtain a representation of the image at a lower resolution, or signal-to-noise ratio – see scalable compression. The codestream obtained after compression of an image with JPEG 2000 can easily be scalable. The main advantage of this photo format is the significant flexibility of the codestream. There is a slight increase in compression performance of JPEG 2000 if we compare it to JPEG. The original JPEG Group was organized in 1986, issuing the first JPEG standard in 1992, which was approved in September 1992 as ITU-T Recommendation T.81 and in 1994 as ISO/IEC 10918-1. On the ITU-T side ITU-T SG16 is the respective body. Currently on the JTC1 side JPEG is one of two sub-groups of ISO/IEC Joint Technical Committee 1, Subcommittee 29, Working Group 1 (ISO/IEC JTC 1/SC 29/WG 1) – titled as Coding of still pictures. In 1987 ISO TC 97 became ISO/IEC JTC1 and in 1992 CCITT became ITU-T. The “Joint” stands for ISO TC97 WG8 and CCITT SGVIII. It is the name of the committee which initiated the JPEG standard and also other still picture coding standards. “JPEG” stands for Joint Photographic Experts Group. The word “rastrum” is now used to refer to a device for drawing musical staff lines.Īn early scanned display with raster computer graphics was invented in the late 1960s by A. The concept originates from the raster scan of cathode ray tube ( CRT) video monitors, which paint the image line by line by magnetically steering a focused electron beam.īesides, it can also refer to a rectangular grid of pixels. The word “raster” has originated from the Latin “rastrum” (a rake), which is derived from radere (to scrape). Vector Illustration & Conversion Services –.
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