A videocompression format or a videocompression specification is a specification for digital ly representing a video as a file or a Bitstream format bitstream . Examples of videocompression formats are H.262 MPEG 2 Part 2 MPEG 2 Part 2 , MPEG 4 Part 2 , H.264 MPEG 4 AVC H.264 MPEG 4 Part 10 , Theora , Dirac videocompression format Dirac , RealVideo RV40, and VP8 . A specific software or hardware implementation of videocompression and or decompression using a specific videocompression format is called a video codec an example of a video codec is Xvid , which implements encoding and decoding videos using the MPEG 4 Part 2 videocompression format in software. A video encoded according to a videocompression format is normally bundled with an audio stream encoded using an audio compression format inside a container format digital Multimedia container formats multimedia container format such as Audio Video Interleave AVI , MP4 , Flash Video FLV , RealMedia , or Matroska . As such, the user normally doesn t have a H.264 MPEG 4 AVC H.264 file, but instead has a .mp4 file, which is an MP4 container containing H.264 encoded video, normally alongside Advanced Audio Coding AAC encoded audio. Multimedia container formats can contain any one of a number of different videocompression formats for example the MP4 container format can contain video in either the MPEG 2 Part 2 or the H.264 videocompression format, among others. Another example is the file type WebM , which specifies the container format Matroska , but also exactly which video VP8 and audio Vorbis compression format is used inside the Matroska container, even though the Matroska container format itself is capable of containing other videocompression formats. it stub Category Video Category Video formats ... more details
01 04 ref latest release date Start date and age 2008 09 23 df yes genre Videocompression format container for contained by MPEG TS , Ogg , Audio Video Interleave AVI , MKV , QuickTime File Format MOV ... a sub set of Dirac free url Dirac is an open and royalty free videocompression format fact According ..., Open Technology VideoCompression for Production and Post Production author Tim Borer year 2007 accessdate ... and royalty free software implementations video codec s of Dirac. Dirac format aims to provide high quality videocompression for Ultra High Definition Television Ultra HDTV and beyond, ref name about ... and is claimed to provide significant savings in data rate and improvements in quality over videocompression ... 2010 08 18 ref ref name smpte vc2 SMPTE 2042 1 2009 VC 2 VideoCompression ref name smpte vc2 ... Compression of 1080P High Definition Video Sources SMPTE 2047 2 2010 Carriage of VC 2 Compressed Video ... compression specifications Dirac, Dirac Pro, and Theora and their open source implementations in Video ... Media Video WMV . Dirac s implementers make the preliminary claim of a two fold reduction in bit rate over MPEG 2 for high definition video , ref cite web url http www.bbc.co.uk rd projects dirac overview.shtml ... and lossless compression modes. ref cite paper url http diracvideo.org download specification dirac ... 2008 09 23 accessdate 2009 10 04 ref Dirac employs wavelet compression , instead of the discrete cosine transform s used in most older compression formats. Dirac is one of several projects attempting to apply wavelets to videocompression. Others include Rududu , ref http rududu.ifrance.com rududu ref Snow codec Snow , cineform , REDCODE and the now discontinued Tarkin codec Tarkin . Wavelet compression is also used in the JPEG 2000 and Progressive Graphics File PGF compression standards for photographic images. Dirac can be used in Audio Video Interleave AVI , Ogg and Matroska container format ... name vc2 dirac cite web publisher SMPTE title Advancements in Compression and Transcoding 2008 and Beyond ... more details
Unreferenced date October 2008 Mergefrom Intra frame date June 2011 In the field of videocompression a video frame is compressed using different algorithm s with different advantages and disadvantages, centered mainly around amount of data compression . These different algorithms for video frames are called picture types or frame types . The three major picture types used in the different video algorithms are I , P and B . They are different in the following characteristics I frames are the least compressible but don t require other video frames to decode. P frames can use data from previous frames to decompress and are more compressible than I frames. B frames can use both previous and forward frames for data reference to get the highest amount of data compression. Summary Image I P and B frames.svg thumb left 500px A sequence of video frames, consisting of two keyframes I , one forward predicted frame P and one bi directionally predicted frame B . clear There are three types of pictures or frames used in videocompression I frames, P frames, and B frames. An I frame is an Intra coded ..., and thus improve videocompression rates. A P frame Predicted picture holds only the changes in the image ... also Key frame term in animation Inter frame Group of pictures application of frame types Videocompression Datamosh Video References reflist External links http www.stanford.edu bgirod pdfs SettonVCIP2005.pdf Video streaming with SP and SI frames Compression Methods Category Videocompression cs Typ ... notion, as a picture can be either a frame or a field video field . A frame is a complete image captured ... lines composing a partial image. When video is sent in Interlaced video interlaced scan format, each ... macroblocks B frames can contain intra, predicted, or bi predicted macroblocks Furthermore, in the video ... reference fields Multi frame motion estimation will allow increases in the quality of the video while allowing the same compression ratio. SI SP frames defined for Extended Profile will allow for increases ... more details
wiktionary compression compressor Compression may refer to In physical science Compression physical , the result of the subjection of a material to compressive stress Compression member , a class of structural ... of volume change resulting from pressure Gas compression , raising the pressure and reducing the volume of gases Compression ratio , a figure of merit of an internal combustion engine Compression geology , a system of forces that tend to decrease the volume of rocks In information science Data compression , the process of encoding digital information using fewer bits Audio compression data , the compression of digital audio streams and files Bandwidth compression , a reduction in either the time to transmit or in the amount of bandwidth required to transmit Compression artifact , noticeable defects in audio or video that has been compressed Image compression , the application of data compression on digital images Videocompression , the compression of digital video streams and files One way compression function , a cryptographic primitive In engineering Dynamic range compression , a compression process that reduces the dynamic range of an audio signal Gain compression , in electronic ... Brain compression , a potentially fatal condition where pressure is exerted on the brain by internal bleeding Bandage Compression bandage Compression bandage , a bandage that uses compression to reduce the flow of blood Intravenous pyelogram compressionCompression in pyelography involves pressing on the lower abdominal area, resulting in distension of the upper urinary tract. In mathematics Compression functional analysis , the compression of a linear operator T on a Hilbert space to a subspace K is the operator Other Compression phonetics , running syllables together in informal speech Please ..., until this articl is created, please do not shorten the description. Compression zoology when an animal ... See also Compaction disambiguation compress Compression shorts Compressor disambiguation Decompression ... more details
Texture compression is a specialized form of image compression designed for storing texture map s in 3D computer graphics rendering systems. Unlike conventional image compression algorithms, texture compression algorithms are optimized for random access . How it works In their seminal paper on http graphics.stanford.edu projects flashg papers texture compression texture compression ref Citation author Andrew Beers coauthors Maneesh Agrawala, Navin Chaddha title Rendering from Compressed Textures journal Computer Graphics, Proc. SIGGRAPH year 1996 pages 373 378 ref , Beers, Agrawala and Chaddha list four features that tend to differentiate texture compression from other image compression techniques. These features are Decoding Speed It is highly desirable to be able to render directly from the compressed texture data and so, in order not to impact rendering performance, decompression must ... , any texture compression scheme must allow fast random access to decompressed texture data. This tends to rule out image compression schemes such as JPEG or Run length encoding . Compression Rate and Visual Quality In a rendering system, lossy compression can be more tolerable than for other use cases. Encoding Speed Texture compression is more tolerant of asymmetric encoding decoding rates as the encoding ..., most texture compression algorithms involve some form of fixed rate lossy compression lossy vector ... maps, texture compression may also be used to encode other kinds of rendering map, including bump map s and normal mapping surface normal map s. Texture compression may also be used together with other ... of practical texture compression systems are S3 Texture Compression , PVRTC and Ericsson Texture Compression . OpenGL and OpenGL ES, as implemented on many video accelerator cards and mobile GPUs, can support multiple common kinds of texture compression generally through the use of vendor extensions ... Compression Category Texture compression compu graphics stub de Texturkomprimierung es Compresi n de ... more details
?docid 163332982698249627 MIT Linear Algebra Lecture on Image Compression at Google Video, from MIT OpenCourseWare ...nofootnotes date April 2010 The objective of image compression is to reduce irrelevance and redundancy ... technique Lossy and lossless compression Image compression may be lossy compression lossy or lossless compression lossless . Lossless compression is preferred for archival purposes and often for medical imaging, technical drawings, clip art , or comics. This is because lossy compression methods, especially when used at low bit rate s, introduce compression artifact s. Lossy methods are especially ... loss of fidelity is acceptable to achieve a substantial reduction in bit rate. The lossy compression that produces imperceptible differences may be called visually lossless compression visually lossless . Methods for lossless image compression are Run length encoding used as default method in PCX and as one ... code s Methods for lossy compression Reducing the color space encoding color space to the most ... image processing quantization and entropy coding . Fractal compression . Other properties The best image quality at a given bit rate or compression rate is the main goal of image compression, however, there are other important properties of image compression schemes Scalability generally refers ... compression . Other names for scalability are progressive coding or embedded bitstreams . Despite ..., and author or copyright information. Processing power . Compression algorithms require different amounts of processing power to encode and decode. Some high compression algorithms require high processing power. The quality of a compression method often is measured by the Peak signal to noise ratio . It measures the amount of noise introduced through a lossy compression of the image, however ... Image compression A study about image compression Image compression basics and comparing different compression methods like JPEG2000, JPEG and JPEG XR HD Photo http dvd hq.info data compression.php ... more details
, audio and video. http membled.com work apps lossy png Lossy PNG image compression research http ... Original image small lossless data compression lossless Portable Network Graphics PNG , 60.1 kilobyte ... compression small 84 less information than uncompressed PNG, 9.37 KB small image3 LossyDemonstration 92less.jpg caption3 Medium compression small 92 less information than uncompressed PNG, 4.82 KB small image4 LossyDemonstration 98less.jpg caption4 High compression small 98 less information than uncompressed PNG, 1.14 KB small In information technology , lossy compression is a data compression data ... to be noticed by the user. Lossy compression is most commonly used to compress multimedia data Sound recording and reproduction audio , video , and image still images , especially in applications such as streaming media and VOIP internet telephony . By contrast, lossless data compression lossless compression is required for text and data files, such as bank records and text articles. In many ... image on a web page. Lossy and lossless compression It is possible to compress many types of digital .... Developing lossy compression techniques as closely matched to human perception as possible is a complex ..., lossy compression can be thought of as an application of transform coding in the case of multimedia ... more accurately to human audio perception. While data reduction compression, be it lossy or lossless ... bit rate and depth. This compression becomes a selective loss of the least significant data ... in color television, encoding color via a Luminance video luminance chrominance transform domain such as YUV ... to each component... Information loss Lossy compression formats suffer from generation loss repeatedly ... with lossless data compression , where data will not be lost via the use of such a procedure. information theory Information theoretical foundations for lossy data compression are provided ... compression schemes In lossy transform codec s , samples of picture or sound are taken, chopped ... more details
Unreferenced stub auto yes date December 2009 Compression Networks is a digital content delivery system developed by TV COM International that evolved into the current DVB S standard for satellite broadcasting . The system provided MPEG2 video, audio, signalling, enhanced program guide, and conditional access for pay television services like AlphaStar . See also EchoStar Category Satellite television Category Broadcasting Category Video Tv tech stub ... more details
built in. Video When motion prediction is used, as in MPEG 1 , MPEG 2 or MPEG 4 , compression artifacts ... dinhpatry Phuc Tue Le Dinh and Jacques Patry. http www.videsignline.com howto 180207350 Videocompression artifacts and MPEG noise reduction . Video Imaging DesignLine. February 24, 2006. Retrieved .... http vimeo.com 2564771 Example of heavy videocompression artefacts . http www.jpegtutor.co.uk ... compression A compression artifact or artefact is a noticeable distortion of media including images , Sound recording audio , and video caused by the application of lossy data compression . Lossy data compression involves discarding some of the media s data so that it becomes simplified enough to be stored ..., the result is a diminishing of quality, or introduction of artifacts. Alternatively, the compression ... subjective importance and those objectionable to the viewer. Compression artifacts occur in many common ... s, Red Book audio CD standard Audio CD s, and WAV files or lossless data compression losslessly compressed media such as FLAC or Portable Network Graphics PNG do not suffer from compression artifacts. The minimization of perceivable artifacts is a key goal in implementing a lossy compression ... 2011 12 23 ref Technically speaking, a compression artifact is a particular class of data error that is usually the consequence of Quantization signal processing quantization in lossy data compression ... of JPEG compression on a slightly noisy image with a mixture of text and whitespace. Text is a screen ... to reduce image compression effects, but to use standardized compression decompression techniques and retain the benefits of compression for instance, lower transmission and storage costs , many of these methods ... 2006 02 algolith fig2.jpg Static illustration of edge busyness ref name dinhpatry in video these artifacts vary, looking like swarming mosquitoes. Videocompression artifacts include cumulative results of compression of the comprising still images, for instance Ringing artifacts JPEG ringing ... more details
Sensing Symposium paper Achieving high data compression of self similar satellite images using fractal. ref have been achieved with acceptable results. Fractal videocompression ratios of 25 1 244 1 have been achieved in reasonable compression times 2.4 to 66 sec frame . ref http cat.inist.fr ?aModele afficheN&cpsidt 1572685 Fractal encoding of video sequences ref Compression efficiency increases ... considerable resources to bring fractal compression to video. While compression results were promising, computer hardware of that time lacked the processing power for fractal videocompression to be practical .... ClearVideo also known as RealVideo Fractal and SoftVideo were early fractal videocompression ...Fractal compression is a lossy compression method for digital image s, based on fractal s. The method ... to do this efficiently. A simple approach ref cite news last Fischer first Y. title Fractal Image Compression ... based image representations. Features With fractal compression, encoding is extremely computationally ... fast. While this asymmetry has so far made it impractical for real time applications, when video is archived for distribution from disk storage or file downloads fractal compression becomes more competitive. ref http www.cas.sc.edu geog rslab Rscc mod2 2 4 2 4.html Image Compression Alternatives and Media Storage Considerations Georgia Institute of Technology reference to compression decompression ... ref At common compression ratios, up to about 50 1, Fractal compression provides similar results to Discrete ... authorlink coauthors title Introduction to Data Compression, Third Edition publisher Morgan Kaufmann year 2005 location pages 560 569 url doi id isbn 0 12 620862 X ref At high compression ratios fractal compression may offer superior quality. For satellite imagery, ratios of over 170 1 ref http ieeexplore.ieee.org ... independence and fractal scaling An inherent feature of fractal compression is that images become resolution ... article on fractal compression resolution independence ref after being converted to fractal code. This is because ... more details
A compression driver is a type of loudspeaker driver which uses the technique of compression to achieve high efficiencies. In this context compression refers to the fact that the area of the loudspeaker diaphragm is significantly larger than the aperture through which the sound is radiated. Compression ... in conjunction with Horn acoustic acoustical horns . Horn loaded Compression Drivers can achieve extremely ..., thus allowing for much better energy transfer. In the Hanna and Slepian proposal the compression ... from compression cavity to horn throat. They found that the bandwidth of the transducer ... resonances in compression cavity is reduced. The paper described the first generation compression driver with a field coil magnet and phase plug, It used aluminum diaphragm with an edge ... LOUDSPEAKERS ref The first commercial compression driver was introduced 1933 when Bell Labs added a Western Electric No. 555 compression driver as a mid range driver to their the two way divided ... of audiovideo technology.html The Short History of Audio Video Technology ref In 1953 Bob Smith made the most significant contribution to modern phase plug, and hence compression driver design, with his ... issue 2 ref in which Smith analyzed the acoustical resonances occurring in the compression cavity ... Society volume preprint 1384 ref . Today the majority of compression drivers, either by inheritance ... month October title A New Methodology for the Acoustic Design of Compression Driver Phase Plugs with Concentric ... volume preprint 7258 ref using a more accurate analytical acoustical model of the compression ... eliminate all traces of acoustical resonance in the compression cavity. Interestingly, in this work .... Compression driver protection In some Sound reinforcement system sound reinforcement and studio ... power thus limiting the power available to the compression driver. ref http www.audioxpress.com ... WESTERN ELECTRIC speakers DEFAULTSORT Compression Driver Category Loudspeaker technology ... more details
Compression therapy may refer to Attachment therapy , a loosely identified category of mental health interventions Cold compression therapy , to reduce pain and swelling from a sports or activity injury disambig ... more details
Context date November 2010 Accessibility dispute date January 2011 Signaling compression , or SigComp , is a compression method designed especially for compression of text based communication data as Session Initiation Protocol SIP or RTSP . SigComp had originally been defined in RFC 3320 and was later updated with RFC 4896. A Negative Acknowledgement Mechanism for Signaling Compression is defined in RFC 4077. The SigComp work is performed in the ROHC working group in the transport area of the IETF . General architecture center Image SigComp Architecture.png center Related standards documents RFC 3320 Signaling Compression SigComp RFC 3321 Signaling Compression SigComp Extended Operations RFC 3485 The Session Initiation Protocol SIP and Session Description Protocol SDP Static Dictionary for Signaling Compression SigComp RFC 3486 Compressing the Session Initiation Protocol SIP RFC 4077 A Negative Acknowledgement Mechanism for Signaling Compression RFC 4464 Signaling Compression SigComp Users Guide RFC 4465 Signaling Compression SigComp Torture Tests RFC 4896 Signaling Compression SigComp Corrections and Clarifications RFC 5049 Applying Signaling Compression SigComp to the Session Initiation Protocol SIP RFC 5112 The Presence Specific Static Dictionary for Signaling Compression Sigcomp 3GPP TR23.979 Annex C Required SigComp performance Category Data compression Category Multimedia Category Telecommunications Category VoIP protocols Category Presentation layer protocols fr SigComp ... more details
Audio compression may refer to Audio compression data , a type of lossy compression in which the amount of data in a recorded waveform is reduced for transmission with some loss of quality, used in CD and MP3 encoding, Internet radio, and the like Dynamic range compression , also called audio level compression, in which the dynamic range, the difference between loud and quiet, of an audio waveform is reduced disambig zh ... more details
Expert subject Computing date May 2011 Adaptive compression is a type of data compression which changes compression algorithm s based on the type of data being compressed. ref name PCMag Cite web url http www.pcmag.com encyclopedia term 0,2542,t adaptive compression&i 37503,00.asp work PC Magizine Encyclopedia title Adaptive compression accessdate 21 April 2011 ref References reflist Category Data compression Computing stub ... more details
Other uses Volume disambiguation Unreferenced date December 2009 A volume is a term in data compression for a file that has been compressed and split into different parts. There are many advantages in having a compression utility with the ability for compression into volumes. First, it allows an individual to download the file in segments at his or her own pace. As well if there is a corruption only one volume is affected instead of the whole which can be corrected using parity file s. Second, it allows compression to a volume size compatible with removable media. For example, compressing a backup into 700MB chunks for easy storage on CDs. See also Compression utilities with volume support RAR ARJ 7 Zip PeaZip DEFAULTSORT Volume Compression Category Data compression ru uk ... more details
index.php?menuphp menu dss&mainpage rajski abs video of an IEEE lecture on test compression sponsored ...Test Compression is a technique used to reduce the time and cost of testing integrated circuit s. The first ICs were tested with test vectors created by hand. It proved very difficult to get good coverage of potential faults, so Design for test ability DFT based on scan and automatic test pattern generation ATPG were developed to explicitly test each gate and path in a design. These techniques were very successful at creating high quality vectors for manufacturing test, with excellent test coverage. However, as chips got bigger the ratio of logic to be tested per pin increased dramatically, and the volume of scan test data started causing a significant increase in test time, and required tester memory. This raised the cost of testing. Test compression was developed to help address this problem. When an ATPG tool generates a test for a fault, or a set of faults, only a small percentage of scan cells need to take specific values. The rest of the scan chain is don t care , and are usually filled with random values. Loading and unloading these vectors is not a very efficient use of tester time. Test compression takes advantage of the small number of significant values to reduce test data and test time. In general, the idea is to modify the design to increase the number of internal scan chains, each of shorter length. These chains are then driven by an on chip decompressor, usually designed to allow continuous flow decompression where the internal scan chains are loaded as the data is delivered to the decompressor. Many different decompression methods can be used. ref cite journal title Survey of Test Vector Compression Techniques author Touba, NA journal IEEE Design & Test of Computers volume 23 issue 4 pages 294 303 year 2006 url http ieeexplore.ieee.org xpls abs all.jsp?arnumber ... , the test compression based on this method often results in compression ratios of 30 to 500 times ... more details
Speech compression may mean different things Speech encoding refers to compression for transmission or storage, possibly to an unintelligible state, with decompression used prior to playback. Time compressed speech refers to voice compression for immediate playback, without any decompression so that the final speech sounds faster to the listener . disambig ... more details
Cord compression may refer to Spinal cord compression Umbilical cord compression disambig Short pages monitor This long comment was added to the page to prevent it being listed on Special Shortpages. It and the accompanying monitoring template were generated via Template Longcomment. Please do not remove the monitor template without removing the comment as well. ... more details
Voice compression may mean different things Speech encoding refers to compression for transmission or storage, possibly to an unintelligible state, with decompression used prior to playback. Time compressed speech refers to voice compression for immediate playback, without any decompression so that the final speech sounds faster to the listener . Audio level compression refers to a sound recording effect which increases the perceived volume of a sound. Disambig ... more details
Unreferenced date February 2010 Silence Compression provides an excellent way to squeeze Data redundancy redundancy out of the sound files. Silence compression scheme is essential for efficient voice communication system. It allows significant reduction of transmission bandwidth during silence period. A Silence compression scheme include a voice activity detection VAD , a silence insertion descriptor SID and a comfort noise generator CNG module. Parameters used for silence compression threshold value the way to encode silence threshold for recognizing start of silence an indication of when silence is over parameter to get threshold, means there is no silence until unless there is three silence in the rows. Sound tech stub Category Data compression ... more details
In telecommunication , the term signal compression has the following meanings In analog usually audio systems, reduction of the dynamic range of a Signalling telecommunication signal by controlling it as a function of the inverse relationship of its instantaneous value relative to a specified reference level. Signal compression is usually expressed in decibel dB . Instantaneous values of the input signal that are low, relative to the reference level, are increased, and those that are high are decreased. Signal compression is usually accomplished by separate devices called compressors. It is used for many purposes, such as a improving signal to noise ratios prior to digitizing an analog signal for transmission telecommunications transmission over a digital carrier system , b preventing overload of succeeding elements of a system, or c matching the dynamic ranges of two devices. Signalling telecommunication Signal compression in dB may be a linear or nonlinear function of the signal level across the frequency band radio band of interest and may be essentially instantaneous or have fixed or variable delay times. Signal compression always introduces distortion , which is usually not objectionable, if the compression is limited to a few dB. The original dynamic range of a compressed signal may be restored by a Electronic circuit circuit called an Companding expander . FS1037C MS188 See also Companding Dynamic range compression Further reading http www.atis.org tg2k signal compression.html Definition signal compression http users.ece.gatech.edu vkm nii node36.html Signal Compression http www.ece.ucsb.edu scl Signal Compression Lab UCSB http www.stanford.edu group compression Signal Compression and Classification Group Stanford Category Electronics terms Category Signal processing Category Telecommunications terms he ... more details
Orphan date February 2009 Compression , in astronomy is the deviation of a heavenly body from the spherical form, called also the ellipticity . It is numerically expressed by the ratio of the differences of the axes to the major axis of the spheroid. The compression or flattening of the earth is about 1 298, which means that the ratio of the equatorial to the polar axis is 298 297 References 1911 astronomy stub Category Astrometry ... more details
Compression shorts are underwear undergarments usually worn by athletes. They are form fitting garment s and when worn cover the athlete s waist to mid or lower thigh. These garments are often made from a spandex type material, similar to cycling shorts . A major benefit of compression shorts are that they keep the thigh muscles warm to reduce muscle strain and fatigue. In addition, there is some evidence that compression shorts may enhance athletic performance. ref cite journal doi 10.1080 0264041031000101971 author Doan BK, Kwon YH, Newton RU, et al. title Evaluation of a lower body compression garment journal J Sports Sci volume 21 issue 8 pages 601 10 year 2003 month Aug pmid 12875311 ref They are also used as a way to keep the male genitalia in place. Compression shorts also help to keep .... Another major benefit is that many compression shorts are designed to wick sweat away from the body ... things like walking or running when the thighs are adducted. There are also other types of compression garments that serve a similar function, such as compression t shirts, socks, sleeves & tights ... such as compression shorts have seen an increase in popularity, arguably because of their comparable ... all the jockstraps gone? work Slate Magazine 2005 07 22 ref Compression shorts are also popular among ..., athletes wear compression shorts under the skirt so if they fall over and their skirts ride up ... both being no contact sports in which players often wear skirts . In this situation, compression shorts are colloquially identified as spandex shorts. Women also wear compression shorts in tennis where most recently, compression shorts have been produced with ball pockets for convenience. There are also women s compression shorts for use before, during and after pregnancy. Pregnancy compression shorts ... url http www.recoveryshorts.com.au title Women s pregnancy compression shorts 2011 05 31 ref See also Compression sportswear Rugby shorts Sports clothing References reflist Men s undergarments Clothing ... more details
File Compression test.jpg right thumb 250px Compression test on a universal testing machine Physical compression is the result of the subjection of a material or structure to Stress mechanics compressive stress , which results in reduction of volume as compared to an uncompressed but otherwise identical state. The opposite of compression in a solid is tension physics tension . In any medium transmitting waves, the opposite of compression is rarefaction . In simple terms, compression is a pushing force. Explanation Compression has many implications in materials science , physics and structural engineering , for compression yields noticeable amounts of Stress physics stress and tension mechanics tension . By inducing compression, mechanical properties such as compressive strength or modulus of elasticity , can be measured. Scientist s and engineer s may utilize compression machines to measure the resistance of materials and structures to compression. Compression machines range from very small table top systems to ones with over 53 MN capacity. ref Citation last NIST title Large Scale Structure Testing Facility url http www.nist.gov bfrl facilities instruments large scale struct testing fac.cfm accessdate 04 05 2010 postscript . ref In engines Internal combustion engines In internal combustion engine s it is a necessary condition of economy to compress the explosive mixture before it is ignited in the Otto cycle , for instance, the second stroke of the piston effects the compression of the charge which has been drawn into the cylinder by the first forward stroke. Steam engines The term is applied to the arrangement by which the exhaust valve of a steam engine is made to close ... in the mechanism due to the inertia of the reciprocating parts are lessened. This compression, moreover ... stroke. See also Box compression test Buckling Compression member Longitudinal wave P wave ... f sica ru simple Physical compression ... more details
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