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Joint Bi-level Image Experts Group
The Joint Bi-level Image Experts Group (JBIG) is a group of experts nominated by national standards bodies and major companies to work to produce standards for bi-level image coding. The "joint" refers to its status as a committee working on both ISO and ITU-T standards. It 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), whose official title is ''Coding of still pictures''. The Joint Bi-level Image Experts Group created the JBIG and JBIG2 standards. The group often meets jointly with the JPEG committee, which typically meets three times annually. ISO/IEC JTC1 SC29 Working Group 1 (working together with ITU-T Study Group 16 – VCEG and previously also with Study Group 8 – SG8) is responsible for both JPEG and JBIG standards. It includes two sub-groups: the Joint Photographic Experts Group (JPEG SG) and the Joint Bi-level Image experts Group (JBIG SG). In the mid-1980s, both CCITT (now IT ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Binary Image
A binary image is one that consists of pixels that can have one of exactly two colors, usually black and white. Binary images are also called ''bi-level'' or ''two-level'', Pixelart made of two colours is often referred to as ''1-Bit'' or ''1bit''. This means that each pixel is stored as a single bit—i.e., a 0 or 1. The names ''black-and-white'', ''B&W'', monochrome or monochromatic are often used for this concept, but may also designate any images that have only one sample per pixel, such as grayscale images. In Photoshop parlance, a binary image is the same as an image in "Bitmap" mode. Binary images often arise in digital image processing as masks or thresholding, and dithering. Some input/output devices, such as laser printers, fax machines, and bilevel computer displays, can only handle bilevel images. A binary image can be stored in memory as a bitmap, a packed array of bits. A 640×480 image requires 37.5 KiB of storage. Because of the small size of the image file ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Organization For Standardization
The International Organization for Standardization (ISO ) is an international standard development organization composed of representatives from the national standards organizations of member countries. Membership requirements are given in Article 3 of the ISO Statutes. ISO was founded on 23 February 1947, and (as of November 2022) it has published over 24,500 international standards covering almost all aspects of technology and manufacturing. It has 809 Technical committees and sub committees to take care of standards development. The organization develops and publishes standardization in all technical and nontechnical fields other than electrical and electronic engineering, which is handled by the IEC.Editors of Encyclopedia Britannica. 3 June 2021.International Organization for Standardization" ''Encyclopedia Britannica''. Retrieved 2022-04-26. It is headquartered in Geneva, Switzerland, and works in 167 countries . The three official languages of the ISO are English, Fren ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ITU-T
The ITU Telecommunication Standardization Sector (ITU-T) is one of the three sectors (divisions or units) of the International Telecommunication Union (ITU). It is responsible for coordinating standards for telecommunications and Information Communication Technology such as X.509 for cybersecurity, Y.3172 and Y.3173 for machine learning, and H.264/MPEG-4 AVC for video compression, between its Member States, Private Sector Members, and Academia Members. The first meeting of the World Telecommunication Standardization Assembly (WTSA), the sector's governing conference, took place on 1 March of that year. ITU-T has a permanent secretariat called the Telecommunication Standardization Bureau (TSB), which is based at the ITU headquarters in Geneva, Switzerland. The current director of the TSB is Chaesub Lee (of South Korea), whose first 4-year term commenced on 1 January 2015, and whose second 4-year term commenced on 1 January 2019. Chaesub Lee succeeded Malcolm Johnson (Director), Malc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Electrotechnical Commission
The International Electrotechnical Commission (IEC; in French: ''Commission électrotechnique internationale'') is an international standards organization that prepares and publishes international standards for all electrical, electronic and related technologies – collectively known as "electrotechnology". IEC standards cover a vast range of technologies from power generation, transmission and distribution to home appliances and office equipment, semiconductors, fibre optics, batteries, solar energy, nanotechnology and marine energy as well as many others. The IEC also manages four global conformity assessment systems that certify whether equipment, system or components conform to its international standards. All electrotechnologies are covered by IEC Standards, including energy production and distribution, electronics, magnetics and electromagnetics, electroacoustics, multimedia, telecommunication and medical technology, as well as associated general disciplines such as t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
JBIG
JBIG is an early lossless image compression standard from the Joint Bi-level Image Experts Group, standardized as ISO/IEC standard 11544 and as ITU-T recommendation T.82 in March 1993. It is widely implemented in fax machines. Now that the newer bi-level image compression standard JBIG2 has been released, JBIG is also known as JBIG1. JBIG was designed for compression of binary images, particularly for faxes, but can also be used on other images. In most situations JBIG offers between a 20% and 50% increase in compression efficiency over Fax Group 4 compression, and in some situations, it offers a 30-fold improvement. JBIG is based on a form of arithmetic coding developed by IBM (known as the Q-coder) that also uses a relatively minor refinement developed by Mitsubishi The is a group of autonomous Japanese multinational companies in a variety of industries. Founded by Yatarō Iwasaki in 1870, the Mitsubishi Group historically descended from the Mitsubishi zaibatsu, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
JBIG2
JBIG2 is an image compression standard for bi-level images, developed by the Joint Bi-level Image Experts Group. It is suitable for both lossless and lossy compression. According to a press release from the Group, in its lossless mode JBIG2 typically generates files 3–5 times smaller than Fax Group 4 and 2–4 times smaller than JBIG, the previous bi-level compression standard released by the Group. JBIG2 was published in 2000 as the international standard ITU T.88, and in 2001 as ISO/ IEC 14492. Functionality Ideally, a JBIG2 encoder will segment the input page into regions of text, regions of halftone images, and regions of other data. Regions that are neither text nor halftones are typically compressed using a context-dependent arithmetic coding algorithm called the MQ coder. Textual regions are compressed as follows: the foreground pixels in the regions are grouped into symbols. A dictionary of symbols is then created and encoded, typically also using context-dependent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ISO/IEC JTC 1
ISO/IEC JTC 1, entitled "Information technology", is a joint technical committee (JTC) of the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC). Its purpose is to develop, maintain and promote standards in the fields of information and communications technology (ICT). JTC 1 has been responsible for many critical IT standards, ranging from the Joint Photographic Experts Group (JPEG) image formats and Moving Picture Experts Group (MPEG) audio and video formats to the C and C++ programming languages. History ISO/IEC JTC 1 was formed in 1987 as a merger between ISO/TC 97 (Information Technology) and IEC/TC 83, with IEC/SC 47B joining later. The intent was to bring together, in a single committee, the IT standardization activities of the two parent organizations in order to avoid duplicative or possibly incompatible standards. At the time of its formation, the mandate of JTC 1 was to develop base standards in information tec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
VCEG
The Video Coding Experts Group or Visual Coding Experts Group (VCEG, also known as Question 6) is a working group of the ITU Telecommunication Standardization Sector (ITU-T) concerned with standards for compression coding of video, images, audio, and other signals. It is responsible for standardization of the "H.26x" line of video coding standards, the "T.8xx" line of image coding standards, and related technologies. Administratively, VCEG is the informal name of Question 6 (Visual, audio and signal coding) of Working Party 3 (Audiovisual technologies and intelligent immersive applications) of ITU-T Study Group 16 (Multimedia and related digital technologies). Its abbreviated title is ITU-T Q.6/SG16, or more simply, ITU-T Q6/16. The goal of VCEG is to produce ITU-T Recommendations (international standards) for video coding and image coding methods appropriate for conversational (e.g. videoconferencing and video telephony) and non-conversational (e.g., streaming, broadcast, file d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
JPEG
JPEG ( ) is a commonly used method of lossy compression for digital images, particularly for those images produced by digital photography. The degree of compression can be adjusted, allowing a selectable tradeoff between storage size and image quality. JPEG typically achieves 10:1 compression with little perceptible loss in image quality. Since its introduction in 1992, JPEG has been the most widely used image compression standard in the world, and the most widely used digital image format, with several billion JPEG images produced every day as of 2015. The term "JPEG" is an acronym for the Joint Photographic Experts Group, which created the standard in 1992. JPEG was largely responsible for the proliferation of digital images and digital photos across the Internet, and later social media. JPEG compression is used in a number of image file formats. JPEG/Exif is the most common image format used by digital cameras and other photographic image capture devices; along with JPEG ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Joint Photographic Experts Group
The Joint Photographic Experts Group (JPEG) is the joint committee between ISO/IEC JTC 1/SC 29 and ITU-T Study Group 16 that created and maintains the JPEG, JPEG 2000, JPEG XR, JPEG XT, JPEG XS, JPEG XL, and related digital image standards. It also has the responsibility for maintenance of the JBIG and JBIG2 standards that were developed by the former Joint Bi-level Image Experts Group. Within ISO/IEC JTC 1, JPEG is Working Group 1 (WG 1) of Subcommittee 29 (SC 29) and has the formal title ''JPEG Coding of digital representations of images'', where it is one of eight working groups in SC 29. In the ITU-T (formerly called the CCITT), its work falls in the domain of the ITU-T Visual Coding Experts Group (VCEG), which is Question 6 of Study Group 16. JPEG has typically held meetings three or four times annually in North America, Asia and Europe (with meetings held virtually during the COVID-19 pandemic). The chairman of JPEG (termed its ''Convenor'' in ISO/IEC terminology) is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
JBIG1
JBIG is an early lossless image compression standard from the Joint Bi-level Image Experts Group, standardized as ISO/ IEC standard 11544 and as ITU-T recommendation T.82 in March 1993. It is widely implemented in fax machines. Now that the newer bi-level image compression standard JBIG2 has been released, JBIG is also known as JBIG1. JBIG was designed for compression of binary images, particularly for faxes, but can also be used on other images. In most situations JBIG offers between a 20% and 50% increase in compression efficiency over Fax Group 4 compression, and in some situations, it offers a 30-fold improvement. JBIG is based on a form of arithmetic coding developed by IBM (known as the Q-coder) that also uses a relatively minor refinement developed by Mitsubishi, resulting in what became known as the QM-coder. It bases the probability estimates for each encoded bit on the values of the previous bits and the values in previous lines of the picture. JBIG also supports p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Moving Picture Experts Group
The Moving Picture Experts Group (MPEG) is an alliance of working groups established jointly by ISO and IEC that sets standards for media coding, including compression coding of audio, video, graphics, and genomic data; and transmission and file formats for various applications.John Watkinson, ''The MPEG Handbook'', p. 1 Together with JPEG, MPEG is organized under ISO/IEC JTC 1/SC 29 – ''Coding of audio, picture, multimedia and hypermedia information'' (ISO/IEC Joint Technical Committee 1, Subcommittee 29). MPEG formats are used in various multimedia systems. The most well known older MPEG media formats typically use MPEG-1, MPEG-2, and MPEG-4 AVC media coding and MPEG-2 systems transport streams and program streams. Newer systems typically use the MPEG base media file format and dynamic streaming (a.k.a. MPEG-DASH). History MPEG was established in 1988 by the initiative of Dr. Hiroshi Yasuda ( NTT) and Dr. Leonardo Chiariglione (CSELT). Chiariglione was the group' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
