279:, which transforms the raw data to a domain that more accurately reflects the information content. For example, rather than expressing a sound file as the amplitude levels over time, one may express it as the frequency spectrum over time, which corresponds more accurately to human audio perception. While data reduction (compression, be it lossy or lossless) is a main goal of transform coding, it also allows other goals: one may represent data more accurately for the original amount of space – for example, in principle, if one starts with an analog or high-resolution
3010:
3000:
551:. If data which has been compressed lossily is decoded and compressed losslessly, the size of the result can be comparable with the size of the data before lossy compression, but the data already lost cannot be recovered. When deciding to use lossy conversion without keeping the original, format conversion may be needed in the future to achieve compatibility with software or devices (
172:
compression techniques as closely matched to human perception as possible is a complex task. Sometimes the ideal is a file that provides exactly the same perception as the original, with as much digital information as possible removed; other times, perceptible loss of quality is considered a valid tradeoff.
151:
needed to transmit it, with no loss of the full information contained in the original file. A picture, for example, is converted to a digital file by considering it to be an array of dots and specifying the color and brightness of each dot. If the picture contains an area of the same color, it can be
171:
In many cases, files or data streams contain more information than is needed. For example, a picture may have more detail than the eye can distinguish when reproduced at the largest size intended; likewise, an audio file does not need a lot of fine detail during a very loud passage. Developing lossy
447:
methods is that in some cases a lossy method can produce a much smaller compressed file than any lossless method, while still meeting the requirements of the application. Lossy methods are most often used for compressing sound, images or videos. This is because these types of data are intended for
347:, allow one to reduce the resolution on the components to accord with human perception – humans have highest resolution for black-and-white (luma), lower resolution for mid-spectrum colors like yellow and green, and lowest for red and blues – thus NTSC displays approximately 350 pixels of luma per
295:
file of the same size. This is because uncompressed audio can only reduce file size by lowering bit rate or depth, whereas compressing audio can reduce size while maintaining bit rate and depth. This compression becomes a selective loss of the least significant data, rather than losing data across
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By modifying the compressed data directly without decoding and re-encoding, some editing of lossily compressed files without degradation of quality is possible. Editing which reduces the file size as if it had been compressed to a greater degree, but without more loss than this, is sometimes also
86:
Well-designed lossy compression technology often reduces file sizes significantly before degradation is noticed by the end-user. Even when noticeable by the user, further data reduction may be desirable (e.g., for real-time communication or to reduce transmission times or storage needs). The most
78:
methods that uses inexact approximations and partial data discarding to represent the content. These techniques are used to reduce data size for storing, handling, and transmitting content. The different versions of the photo of the cat on this page show how higher degrees of approximation create
719:
video, although those prior schemes had limited success in terms of adoption into real-world common usage. Without this capacity, which is often the case in practice, to produce a representation with lower resolution or lower fidelity than a given one, one needs to start with the original source
175:
The terms "irreversible" and "reversible" are preferred over "lossy" and "lossless" respectively for some applications, such as medical image compression, to circumvent the negative implications of "loss". The type and amount of loss can affect the utility of the images. Artifacts or undesirable
1288:, are, like lossy compression, irreversible: the original signal cannot be reconstructed from the transformed signal. However, in general these will have the same size as the original, and are not a form of compression. Lowering resolution has practical uses, as the
167:
file is smaller than its original, but repeatedly compressing the same file will not reduce the size to nothing. Most compression algorithms can recognize when further compression would be pointless and would in fact increase the size of the data.
1512:“Although one main goal of digital audio perceptual coders is data reduction, this is not a necessary characteristic. As we shall see, perceptual coding can be used to improve the representation of digital audio through advanced bit allocation.”
759:
methods. Some audio formats feature a combination of a lossy format and a lossless correction which when combined reproduce the original signal; the correction can be stripped, leaving a smaller, lossily compressed, file. Such formats include
427:, previous and/or subsequent decoded data is used to predict the current sound sample or image frame. The error between the predicted data and the real data, together with any extra information needed to reproduce the prediction, is then
225:. The remaining information can then be compressed via a variety of methods. When the output is decoded, the result may not be identical to the original input, but is expected to be close enough for the purpose of the application.
695:, but this functionality is not supported in all designs, as not all codecs encode data in a form that allows less important detail to simply be dropped. Some well-known designs that have this capability include
130:
which can then be used to produce additional copies from. This allows one to avoid basing new compressed copies off of a lossy source file, which would yield additional artifacts and further unnecessary
630:
Some other transforms are possible to some extent, such as joining images with the same encoding (composing side by side, as on a grid) or pasting images such as logos onto existing images (both via
50:
36:
514:(that is, the size of the compressed file compared to that of the uncompressed file) of lossy video codecs is nearly always far superior to that of the audio and still-image equivalents.
1303:
which progressively defines the image. Thus a partial transmission is enough to preview the final image, in a lower resolution version, without creating a scaled and a full version too.
498:
describes how sound can be highly compressed without degrading perceived quality. Flaws caused by lossy compression that are noticeable to the human eye or ear are known as
83:(reversible data compression) which does not degrade the data. The amount of data reduction possible using lossy compression is much higher than using lossless techniques.
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731:
Another approach is to encode the original signal at several different bitrates, and then either choose which to use (as when streaming over the internet – as in
704:
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or otherwise decrease the resolution of the represented source signal and the quantity of data used for its compressed representation without re-encoding, as in
543:
from the re-encoding. This can be avoided by only producing lossy files from (lossless) originals and only editing (copies of) original files, such as images in
155:
The original data contains a certain amount of information, and there is a lower bound to the size of a file that can still carry all the information. Basic
126:. By contrast, lossless compression is typically required for text and data files, such as bank records and text articles. It can be advantageous to make a
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486:
When a user acquires a lossily compressed file, (for example, to reduce download time) the retrieved file can be quite different from the original at the
181:
456:. Data files using lossy compression are smaller in size and thus cost less to store and to transmit over the Internet, a crucial consideration for
448:
human interpretation where the mind can easily "fill in the blanks" or see past very minor errors or inconsistencies – ideally lossy compression is
435:
In some systems the two techniques are combined, with transform codecs being used to compress the error signals generated by the predictive stage.
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level while being indistinguishable to the human ear or eye for most practical purposes. Many compression methods focus on the idiosyncrasies of
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Still images are often lossily compressed at 10:1, as with audio, but the quality loss is more noticeable, especially on closer inspection.
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effects of compression may be clearly discernible yet the result still useful for the intended purpose. Or lossy compressed images may be '
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2313:
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of its encounter with Pluto-Charon before it sent the higher resolution images. Another solution for slow connections is the usage of
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2708:
2531:
2325:
1175:
1373:"Usability of irreversible image compression in radiological imaging. A position paper by the European Society of Radiology (ESR)"
2016:
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the board. Further, a transform coding may provide a better domain for manipulating or otherwise editing the data – for example,
351:, 150 pixels of yellow vs. green, and 50 pixels of blue vs. red, which are proportional to human sensitivity to each component.
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of audio is most naturally expressed in the frequency domain (boost the bass, for instance) rather than in the raw time domain.
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17:
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363:: repeatedly compressing and decompressing the file will cause it to progressively lose quality. This is in contrast with
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An important caveat about lossy compression (formally transcoding), is that editing lossily compressed files causes
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331:) means that black-and-white sets display the luminance, while ignoring the color information. Another example is
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compressed without loss by saying "200 red dots" instead of "red dot, red dot, ...(197 more times)..., red dot."
743:), or broadcast several, where the best that is successfully received is used, as in various implementations of
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channel). While unwanted information is destroyed, the quality of the remaining portion is unchanged.
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1489:"T.81 – DIGITAL COMPRESSION AND CODING OF CONTINUOUS-TONE STILL IMAGES – REQUIREMENTS AND GUIDELINES"
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says that there is an absolute limit in reducing the size of this data. When data is compressed, its
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signal and encode, or start with a compressed representation and then decompress and re-encode it (
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1600:, Prentice Hall, 1996; JPEG: Chapter 8; H.261: Chapter 9; MPEG-1: Chapter 10; MPEG-2: Chapter 11.
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1108:(Notable for lack of patent restrictions, low delay, and high quality speech and general audio.)
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221:. Knowledge of the application is used to choose information to discard, thereby lowering its
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408:, samples of picture or sound are taken, chopped into small segments, transformed into a new
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file of a given size should provide a better representation than a raw uncompressed audio in
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It is possible to compress many types of digital data in a way that reduces the size of a
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for video. Such schemes have also been standardized for older designs as well, such as
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Data compression approach that reduces data size while discarding or changing some of it
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information, can usually be modified or removed without modifying the underlying data.
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A general kind of lossy compression is to lower the resolution of an image, as in
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Video can be compressed immensely (e.g., 100:1) with little visible quality loss
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Optimizing the compression (to reduce size without change to the decoded image)
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Audio can often be compressed at 10:1 with almost imperceptible loss of quality
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1803:, comparing the suitability of JPG and lossless compression for image archives
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1280:. One may also remove less "lower information" parts of an image, such as by
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1097:(WMA) (Standard and Pro profiles are lossy. WMA Lossless is also available.)
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in 1974. DCT is the most widely used form of lossy compression, for popular
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The most common form of lossy compression is a transform coding method, the
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1936:
1911:
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1776:, comparing the speed and compression strength of five lossy audio formats.
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increases, and it cannot increase indefinitely. For example, a compressed
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217:. The transformation is typically used to enable better (more targeted)
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techniques, although these sometimes fall into the related category of
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Researchers have performed lossy compression on text by either using a
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688:
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Some forms of lossy compression can be thought of as an application of
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From this point of view, perceptual encoding is not essentially about
1782:, including chapters on lossy compression of images, audio and video.
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815:(high-density lossless or lossy compression of RGB and RGBA images)
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233:
92:
379:
in optimal coding theory, rate-distortion theory heavily draws on
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2142:
2091:
1563:"Reminiscences of the Early Work in DCT: Interview with K.R. Rao"
830:
765:
668:
637:
Some changes can be made to the compression without re-encoding:
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461:
275:
In the case of audio data, a popular form of transform coding is
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1207:
1089:
998:
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367:, where data will not be lost via the use of such a procedure.
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coarser images as more details are removed. This is opposed to
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Converting between progressive and non-progressive encoding.
2172:
2026:
2011:
2001:
1748:"Semantic and Generative Models for Lossy Text Compression"
1598:
Techniques and
Standards for Image, Video, and Audio Coding
1289:
1201:
1139:
1004:
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AVC) (may also be lossless, even in certain video sections)
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879:, Progressive Graphics File (lossless or lossy compression)
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The primary programs for lossless editing of JPEGs are
371:
foundations for lossy data compression are provided by
1796:
Using lossy GIF/PNG compression for the web (article)
1570:
102:
Lossy compression is most commonly used to compress
1612:"The Use of FFT and MDCT in MP3 Audio Compression"
683:Downsampling/compressed representation scalability
573:commons:Commons:Software § Ogg Vorbis (audio)
559:for decoding or distribution of compressed files.
182:diagnostically acceptable irreversible compression
1561:Stanković, Radomir S.; Astola, Jaakko T. (2012).
1446:
739:" – or offering varying downloads, as at Apple's
390:in order to model perceptual distortion and even
3031:
1560:
397:There are two basic lossy compression schemes:
202:, which is a type of data compression used for
180:', or in the case of medical images, so-called
87:widely used lossy compression algorithm is the
1668:"The inconvenient truth about Bluetooth audio"
452:(imperceptible), which can be verified via an
1828:
1454:(January 1974), "Discrete Cosine Transform",
841:pixel formats (lossless or lossy compression)
1842:
1256:to substitute short words for long ones, or
319:: in color television, encoding color via a
1698:"What is Sony LDAC, and how does it do it?"
1640:
1634:
1556:
1554:
1552:
1550:
1548:
1546:
1516:, Victor Lombardi, noisebetweenstations.com
1216:(noted for its lack of patent restrictions)
1210:(noted for its lack of patent restrictions)
1114:Adaptive differential pulse-code modulation
1001:(noted for its lack of patent restrictions)
1835:
1821:
1714:
1689:
1659:
774:DTS-HD Master Audio in lossless (XLL) mode
528:
416:. The resulting quantized values are then
1396:
652:has some lossless JPEG operations in its
562:
1745:
1543:
1176:Algebraic code-excited linear prediction
1609:
914:
833:, a successor of JPEG with support for
14:
3032:
1603:
1371:European Society of Radiology (2011).
1267:
1182:Relaxed code-excited linear prediction
869:, used by the Mars Rovers, related to
711:images with progressive encoding, and
604:(which provides a Windows interface).
359:Lossy compression formats suffer from
118:), especially in applications such as
1816:
1665:
1592:
1590:
1440:
827:(BPG) (lossless or lossy compression)
132:
1720:
1695:
854:, JPEG's successor format that uses
724:), though the latter tends to cause
569:commons:Commons:Software § JPEG
505:
443:The advantage of lossy methods over
232:(DCT), which was first published by
1241:(mostly for real-time applications)
1233:Constrained Energy Lapped Transform
354:
187:
55:High-compression (low quality) JPEG
41:Low-compression (high quality) JPEG
24:
1587:
1222:Modified discrete cosine transform
1068:Adaptive Transform Acoustic Coding
1056:Modified discrete cosine transform
25:
3056:
1767:
1284:. Many media transforms, such as
747:. Similar techniques are used in
3009:
3008:
2999:
2998:
1655:from the original on 2017-02-13.
885:Cartesian Perceptual Compression
48:
34:
1739:
1641:Brandenburg, Karlheinz (1999).
898:(lossless or lossy compression)
858:(lossless or lossy compression)
482:Transparency (data compression)
475:
1723:"aptX HD - lossless or lossy?"
1519:
1506:
1481:
1456:IEEE Transactions on Computers
1413:
1364:
1170:Code-excited linear prediction
184:(DAIC) may have been applied.
13:
1:
1666:Darko, John H. (2017-03-29).
1610:Guckert, John (Spring 2012).
1514:Masking and Perceptual Coding
1247:
909:3D computer graphics hardware
438:
3045:Lossy compression algorithms
1120:Master Quality Authenticated
990:High Efficiency Video Coding
819:High Efficiency Image Format
607:These allow the image to be
311:of data. Another use is for
7:
1786:Lossy PNG image compression
1596:K. R. Rao and J. J. Hwang,
1306:
784:
662:
147:needed to store it, or the
10:
3061:
2890:Compressed data structures
2212:RLE + BWT + MTF + Huffman
1880:Asymmetric numeral systems
1809:, Jpg, Png compressor tool
1792: (archived 2005-10-03)
1746:I. H. WITTEN; et al.
1164:Adaptive predictive coding
1149:
1049:
1038:
930:
793:
779:
648:The freeware Windows-only
566:
532:
479:
327:transform domain (such as
191:
91:(DCT), first published by
2994:
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2962:
2880:
2805:
2737:
2728:
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2585:
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2477:
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2301:
2249:Discrete cosine transform
2239:
2230:
2179:LZ77 + Huffman + context
2132:
2042:
1972:
1860:
1851:
1389:10.1007/s13244-011-0071-x
1145:
943:Discrete cosine transform
802:Discrete cosine transform
755:, and more sophisticated
365:lossless data compression
307:data, but rather about a
230:discrete cosine transform
89:discrete cosine transform
81:lossless data compression
2954:Smallest grammar problem
1721:Ford, Jez (2016-11-22).
1696:Ford, Jez (2015-08-24).
1358:
1158:Linear predictive coding
1034:
926:
825:Better Portable Graphics
789:
764:(Scalable to Lossless),
375:. Much like the use of
138:
72:irreversible compression
2895:Compressed suffix array
2444:Nyquist–Shannon theorem
1780:Data compression basics
1643:"MP3 and AAC Explained"
1527:"New jpegtran features"
1494:. CCITT. September 1992
1468:10.1109/T-C.1974.223784
1426:Encyclopedia Britannica
753:pyramid representations
745:hierarchical modulation
726:digital generation loss
619:, or even converted to
581:
541:digital generation loss
529:Transcoding and editing
425:lossy predictive codecs
369:Information-theoretical
1753:. The Computer Journal
1343:Rate–distortion theory
1045:Audio data compression
873:in its use of wavelets
596:(which also preserves
563:Editing of lossy files
555:), or to avoid paying
373:rate-distortion theory
313:backward compatibility
250:video coding standards
64:information technology
18:Lossy data compression
2924:Kolmogorov complexity
2792:Video characteristics
2169:LZ77 + Huffman + ANS
1807:JPG Image Compression
1262:lossy data conversion
1150:Further information:
1128:MPEG-1 Audio Layer II
1080:Advanced Audio Coding
1039:Further information:
980:Advanced Video Coding
931:Further information:
794:Further information:
705:Scalable Video Coding
699:for still images and
533:Further information:
500:compression artifacts
480:Further information:
309:better representation
3014:Compression software
2608:Compression artifact
2564:Psychoacoustic model
1338:Lossless compression
1313:Compression artifact
1029:Sorenson video codec
915:3D computer graphics
770:OptimFROG DualStream
496:psychoacoustic model
317:graceful degradation
128:master lossless file
3004:Compression formats
2643:Texture compression
2638:Standard test image
2454:Silence compression
1774:Lossy audio formats
1268:Lowering resolution
1194:Adaptive Multi-Rate
1095:Windows Media Audio
1041:Audio coding format
1012:Wavelet compression
933:Video coding format
891:Fractal compression
887:, also known as CPC
847:Wavelet compression
236:, T. Natarajan and
95:, T. Natarajan and
2912:Information theory
2767:Display resolution
2593:Chroma subsampling
1982:Byte pair encoding
1927:Shannon–Fano–Elias
1620:University of Utah
1421:"Data compression"
1295:craft transmitted
1136:(based on Musicam)
835:high-dynamic range
667:Metadata, such as
600:information), and
592:, and the derived
333:chroma subsampling
157:information theory
124:internet telephony
3027:
3026:
2876:
2875:
2826:Deblocking filter
2724:
2723:
2572:
2571:
2381:
2380:
2226:
2225:
1801:JPG for Archiving
1450:; Natarajan, T.;
1301:Image interlacing
937:Video compression
796:Image compression
623:(by dropping the
512:compression ratio
506:Compression ratio
468:services such as
460:services such as
277:perceptual coding
264:formats (such as
262:audio compression
244:formats (such as
242:image compression
178:visually lossless
68:lossy compression
16:(Redirected from
3052:
3040:Data compression
3012:
3011:
3002:
3001:
2831:Lapped transform
2735:
2734:
2613:Image resolution
2598:Coding tree unit
2583:
2582:
2392:
2391:
2237:
2236:
1858:
1857:
1844:Data compression
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1693:
1687:
1686:
1684:
1683:
1674:. Archived from
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1411:
1410:
1400:
1377:Insights Imaging
1368:
1318:Data compression
1017:Motion JPEG 2000
907:compression for
701:H.264/MPEG-4 AVC
687:One may wish to
655:
595:
591:
557:patent royalties
545:raw image format
492:human physiology
403:lossy transform
355:Information loss
200:transform coding
194:Transform coding
188:Transform coding
133:information loss
76:data compression
74:is the class of
52:
38:
21:
3060:
3059:
3055:
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3053:
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2990:
2974:
2958:
2939:Rate–distortion
2872:
2801:
2720:
2647:
2568:
2473:
2469:Sub-band coding
2377:
2302:Predictive type
2297:
2222:
2189:LZSS + Huffman
2139:LZ77 + Huffman
2128:
2038:
1974:Dictionary type
1968:
1870:Adaptive coding
1847:
1841:
1790:Wayback Machine
1770:
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1419:
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1414:
1369:
1365:
1361:
1309:
1276:, particularly
1270:
1258:generative text
1250:
1154:
1152:Speech encoding
1148:
1052:
1047:
1037:
982:(AVC / H.264 /
939:
929:
917:
798:
792:
787:
782:
693:bitrate peeling
685:
673:Vorbis comments
665:
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634:), or scaling.
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587:
584:
575:
565:
553:format shifting
537:
531:
508:
484:
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466:streaming audio
458:streaming video
441:
388:decision theory
361:generation loss
357:
196:
190:
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120:streaming media
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1383:(2): 103–115.
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1333:List of codecs
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281:digital master
204:digital images
192:Main article:
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2464:Speech coding
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2459:Sound quality
2457:
2455:
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2450:
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2199:LZ77 + Range
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1678:on 2018-01-14
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1274:image scaling
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1155:
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1141:
1140:aptX/ aptX-HD
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970:MPEG-4 Part 2
968:
965:
964:MPEG-2 Part 2
962:
960:
959:MPEG-1 Part 2
957:
955:
952:
950:
947:
946:
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717:MPEG-4 Part 2
714:
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680:
678:
674:
670:
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654:JPG_TRANSFORM
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628:
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603:
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418:entropy coded
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335:: the use of
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208:digital audio
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145:computer file
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84:
82:
77:
73:
69:
65:
51:
37:
19:
2970:Hutter Prize
2934:Quantization
2839:Compensation
2633:Quantization
2356:Compensation
2231:
1922:Shannon–Fano
1862:Entropy type
1755:. Retrieved
1741:
1730:. Retrieved
1726:
1716:
1705:. Retrieved
1701:
1691:
1680:. Retrieved
1676:the original
1671:
1661:
1636:
1624:. Retrieved
1618:
1605:
1597:
1577:. Retrieved
1573:
1569:
1534:. Retrieved
1530:
1521:
1508:
1496:. Retrieved
1483:
1462:(1): 90–93,
1459:
1455:
1448:Ahmed, Nasir
1442:
1430:. Retrieved
1424:
1415:
1380:
1376:
1366:
1348:Seam carving
1293:New Horizons
1282:seam carving
1271:
1251:
741:iTunes Store
733:RealNetworks
730:
686:
666:
647:
636:
629:
606:
585:
576:
538:
509:
485:
476:Transparency
442:
434:
424:
402:
396:
358:
337:color spaces
308:
304:
302:
298:equalization
274:
227:
219:quantization
197:
174:
170:
154:
142:
101:
85:
71:
67:
61:
2929:Prefix code
2782:Frame types
2603:Color space
2429:Convolution
2159:LZ77 + ANS
2070:Incremental
2043:Other types
1962:Levenshtein
1531:sylvana.net
1353:Transcoding
954:Motion JPEG
757:scale space
722:transcoding
625:chrominance
611:, rotated,
547:instead of
535:Transcoding
450:transparent
410:basis space
377:probability
325:chrominance
234:Nasir Ahmed
93:Nasir Ahmed
3034:Categories
2986:Mark Adler
2944:Redundancy
2861:Daubechies
2844:Estimation
2777:Frame rate
2699:Daubechies
2659:Chain code
2618:Macroblock
2424:Companding
2361:Estimation
2281:Daubechies
1987:Lempel–Ziv
1947:Exp-Golomb
1875:Arithmetic
1757:2007-10-13
1732:2018-01-13
1707:2018-01-13
1682:2018-01-13
1579:13 October
1536:2019-09-20
1452:Rao, K. R.
1297:thumbnails
1278:decimation
1248:Other data
762:MPEG-4 SLS
737:SureStream
689:downsample
578:possible.
567:See also:
439:Comparison
431:and coded.
394:judgment.
384:estimation
343:, used in
305:discarding
104:multimedia
2963:Community
2787:Interlace
2173:Zstandard
1952:Fibonacci
1942:Universal
1900:Canonical
1476:149806273
1432:13 August
1254:thesaurus
1196:(used in
1190:(LD-CELP)
871:JPEG 2000
852:JPEG 2000
697:JPEG 2000
650:IrfanView
621:grayscale
429:quantized
414:quantized
392:aesthetic
321:luminance
258:H.264/AVC
252:(such as
238:K. R. Rao
223:bandwidth
149:bandwidth
99:in 1974.
97:K. R. Rao
2949:Symmetry
2917:Timeline
2900:FM-index
2745:Bit rate
2738:Concepts
2586:Concepts
2449:Sampling
2402:Bit rate
2395:Concepts
2097:Sequitur
1932:Tunstall
1905:Modified
1895:Adaptive
1853:Lossless
1650:Archived
1407:22347940
1307:See also
1134:Musepack
1116:(ADPCM)
856:wavelets
785:Graphics
669:ID3 tags
663:Metadata
632:Jpegjoin
602:Jpegcrop
594:exiftran
589:jpegtran
454:ABX test
445:lossless
381:Bayesian
349:scanline
339:such as
2907:Entropy
2856:Wavelet
2835:Motion
2694:Wavelet
2674:Fractal
2669:Deflate
2652:Methods
2439:Latency
2352:Motion
2276:Wavelet
2193:LHA/LZH
2143:Deflate
2092:Re-Pair
2087:Grammar
1917:Shannon
1890:Huffman
1846:methods
1788:at the
1672:DAR__KO
1626:14 July
1498:12 July
1398:3259360
1224:(MDCT)
1184:(RCELP)
1178:(ACELP)
1082:(AAC /
1070:(ATRAC)
1058:(MDCT)
1050:General
966:(H.262)
905:texture
837:, wide
831:JPEG XR
780:Methods
766:WavPack
749:mipmaps
617:flopped
613:flipped
609:cropped
470:Spotify
462:Netflix
211:signals
161:entropy
3018:codecs
2979:People
2882:Theory
2849:Vector
2366:Vector
2183:Brotli
2133:Hybrid
2032:Snappy
1885:Golomb
1474:
1405:
1395:
1235:(CELT)
1228:AAC-LD
1208:Codec2
1172:(CELP)
1160:(LPC)
1146:Speech
1090:Vorbis
1086:Audio)
1064:(AC-3)
999:Theora
984:MPEG-4
945:(DCT)
821:(HEIF)
804:(DCT)
772:, and
713:MPEG-2
703:based
657:plugin
615:, and
571:, and
412:, and
405:codecs
260:) and
213:, and
116:images
114:, and
106:data (
2809:parts
2807:Codec
2772:Frame
2730:Video
2714:SPIHT
2623:Pixel
2578:Image
2532:ACELP
2503:ADPCM
2493:ÎĽ-law
2488:A-law
2481:parts
2479:Codec
2387:Audio
2326:ACELP
2314:ADPCM
2291:SPIHT
2232:Lossy
2216:bzip2
2207:LZHAM
2163:LZFSE
2065:Delta
1957:Gamma
1937:Unary
1912:Range
1751:(PDF)
1727:AVHub
1702:AVHub
1653:(PDF)
1646:(PDF)
1615:(PDF)
1566:(PDF)
1492:(PDF)
1472:S2CID
1359:Notes
1328:Lenna
1214:Speex
1166:(APC)
1130:(MP2)
1122:(MQA)
1076:(MP3)
1035:Audio
1022:Dirac
974:H.263
949:H.261
927:Video
896:JBIG2
839:gamut
790:Image
675:, or
283:, an
139:Types
112:video
108:audio
2821:DPCM
2628:PSNR
2559:MDCT
2552:WLPC
2537:CELP
2498:DPCM
2346:WLPC
2331:CELP
2309:DPCM
2259:MDCT
2203:LZMA
2104:LDCT
2082:DPCM
2027:LZWL
2017:LZSS
2012:LZRW
2002:LZJB
1628:2019
1581:2019
1500:2019
1460:C-23
1434:2019
1403:PMID
1290:NASA
1239:Opus
1202:3GPP
1200:and
1106:Opus
1101:LDAC
1043:and
1005:VC-1
935:and
921:glTF
902:S3TC
867:ICER
862:DjVu
813:WebP
808:JPEG
715:and
709:JPEG
677:Exif
598:Exif
582:JPEG
549:JPEG
510:The
464:and
386:and
345:NTSC
315:and
293:AIFF
268:and
256:and
254:MPEG
246:JPEG
122:and
2866:DWT
2816:DCT
2760:VBR
2755:CBR
2750:ABR
2709:EZW
2704:DWT
2689:RLE
2679:KLT
2664:DCT
2547:LSP
2542:LAR
2527:LPC
2520:FFT
2417:VBR
2412:CBR
2407:ABR
2341:LSP
2336:LAR
2321:LPC
2286:DWT
2271:FFT
2266:DST
2254:DCT
2153:LZS
2148:LZX
2124:RLE
2119:PPM
2114:PAQ
2109:MTF
2077:DMC
2055:CTW
2050:BWT
2022:LZW
2007:LZO
1997:LZ4
1992:842
1464:doi
1393:PMC
1385:doi
1198:GSM
1084:MP4
996:Ogg
877:PGF
776:).
735:' "
488:bit
423:In
401:In
341:YIQ
329:YUV
291:or
289:WAV
285:MP3
272:).
270:AAC
266:MP3
248:),
165:ZIP
70:or
62:In
3036::
2684:LP
2515:FT
2508:DM
2060:CM
1725:.
1700:.
1670:.
1648:.
1617:.
1589:^
1574:60
1572:.
1568:.
1545:^
1529:.
1470:,
1458:,
1423:.
1401:.
1391:.
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1710:.
1685:.
1630:.
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1539:.
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1436:.
1409:.
1387::
1381:2
1204:)
976:)
972:(
420:.
323:-
20:)
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