Editing Data compression (section)

=== Image ===
{{Main|Image compression}}

[[Entropy coding]] originated in the 1940s with the introduction of [[Shannon–Fano coding]],<ref name="Shannon"/> the basis for [[Huffman coding]] which was developed in 1950.<ref name="Huffman"/> [[Transform coding]] dates back to the late 1960s, with the introduction of [[fast Fourier transform]] (FFT) coding in 1968 and the [[Hadamard transform]] in 1969.<ref name="Hadamard"/>

An important image compression technique is the [[discrete cosine transform]] (DCT), a technique developed in the early 1970s.<ref name="Ahmed"/> DCT is the basis for JPEG, a [[lossy compression]] format which was introduced by the [[Joint Photographic Experts Group]] (JPEG) in 1992.<ref name="t81" /> JPEG greatly reduces the amount of data required to represent an image at the cost of a relatively small reduction in image quality and has become the most widely used [[image file format]].<ref>{{cite web |title=The JPEG image format explained |url=https://home.bt.com/tech-gadgets/photography/what-is-a-jpeg-11364206889349 |website=[[BT.com]] |publisher=[[BT Group]] |access-date=5 August 2019 |date=31 May 2018 |archive-date=5 August 2019 |archive-url=https://web.archive.org/web/20190805194553/https://home.bt.com/tech-gadgets/photography/what-is-a-jpeg-11364206889349 |url-status=dead }}</ref><ref>{{cite news |last1=Baraniuk |first1=Chris |title=Copy protections could come to JPEGs |url=https://www.bbc.co.uk/news/technology-34538705 |access-date=13 September 2019 |work=[[BBC News]] |agency=[[BBC]] |date=15 October 2015}}</ref> Its highly efficient DCT-based compression algorithm was largely responsible for the wide proliferation of [[digital image]]s and [[digital photo]]s.<ref name="Atlantic">{{cite web |title=What Is a JPEG? The Invisible Object You See Every Day |url=https://www.theatlantic.com/technology/archive/2013/09/what-is-a-jpeg-the-invisible-object-you-see-every-day/279954/ |access-date=13 September 2019 |website=[[The Atlantic]] |date=24 September 2013}}</ref>

[[Lempel–Ziv–Welch]] (LZW) is a [[lossless compression]] algorithm developed in 1984. It is used in the [[GIF]] format, introduced in 1987.<ref name="cloanto">{{cite web|url=https://mike.pub/19950127-gif-lzw|title=The GIF Controversy: A Software Developer's Perspective|date=27 January 1995 |access-date=26 May 2015}}</ref> [[DEFLATE]], a lossless compression algorithm specified in 1996, is used in the [[Portable Network Graphics]] (PNG) format.<ref name="IETF">{{cite IETF |title=DEFLATE Compressed Data Format Specification version 1.3 |rfc=1951 |section=Abstract |page=1 |author=L. Peter Deutsch |author-link=L. Peter Deutsch |date=May 1996 |publisher=[[IETF]] |access-date=2014-04-23}}</ref>

[[Wavelet compression]], the use of [[wavelet]]s in image compression, began after the development of DCT coding.<ref name="Hoffman"/> The [[JPEG 2000]] standard was introduced in 2000.<ref>{{cite book |last1=Taubman |first1=David |last2=Marcellin |first2=Michael |title=JPEG2000 Image Compression Fundamentals, Standards and Practice: Image Compression Fundamentals, Standards and Practice |date=2012 |publisher=[[Springer Science & Business Media]] |isbn=9781461507994 |url=https://books.google.com/books?id=y7HeBwAAQBAJ&pg=PA402}}</ref> In contrast to the DCT algorithm used by the original JPEG format, JPEG 2000 instead uses [[discrete wavelet transform]] (DWT) algorithms.<ref name="Unser"/><ref>{{cite web |last1=Sullivan |first1=Gary |title=General characteristics and design considerations for temporal subband video coding |publisher=[[Video Coding Experts Group]] |website=[[ITU-T]] |date=8–12 December 2003 |url=https://www.itu.int/wftp3/av-arch/video-site/0312_Wai/VCEG-U06.doc |access-date=13 September 2019}}</ref><ref>{{cite book |last1=Bovik |first1=Alan C. |title=The Essential Guide to Video Processing |date=2009 |publisher=[[Academic Press]] |isbn=9780080922508 |page=355 |url=https://books.google.com/books?id=wXmSPPB_c_0C&pg=PA355}}</ref> JPEG 2000 technology, which includes the [[Motion JPEG 2000]] extension, was selected as the [[video coding standard]] for [[digital cinema]] in 2004.<ref>{{cite book |last1=Swartz |first1=Charles S. |title=Understanding Digital Cinema: A Professional Handbook |date=2005 |publisher=[[Taylor & Francis]] |isbn=9780240806174 |page=147 |url=https://books.google.com/books?id=tYw3ehoBnjkC&pg=PA147}}</ref>