The compression of binary data into a form which, when it is re-expanded, has most, but not all, of the original information. It is used primarily for compression of images and sounds, and is designed to provide a high degree of compression at the cost of a slight loss of data. It is expemplified by the JPEG compression standard. Images compressed by a lossy compression algorithm are re-expanded into an image close, but not identical to the original image; the difference between the original and the reconstructed image may be imperceptible to normal viewing by the eye.
A type of compression that deliberately sacrifices some of the original data in return for much higher compression ratios than those achievable with lossless techniques.
A compression algorithm that removes some data, to reduce the file size, while preserving the sound or image. Data that is removed is lost, thus altering the original image permanently.
The original data is not completely recoverable. Although image quality may suffer, many experts believe that up to 95 percent of the data in a typical image may be discarded without a noticeable loss in apparent resolution.
(n.) A type of compression that results in the loss of some of the original data. Lossy compression trades the potential for the loss of some image quality for the opportunity for greater compression. Whereas lossless compression results in a compression ratio of about 2:1, lossy compression of video data can lead to ratios of between 10:1 and 50:1 without visibly degrading image quality. JPEG and MPEG are examples of lossy compression techniques.
From Portable Network Graphics (PNG) Specification (Second Edition) ( 2003-11-10) method of data compression that permits reconstruction of the original data approximately, rather than exactly.
A means for reducing the storage space required for an image. The decompressed image has less resolution than the original, although this might not be noticeable to the naked eye.
A compression scheme that does not preserve the data precisely; some data is lost, and it cannot be recovered after compression. Most lossy schemes try to compress the data as much as possible, without decreasing the image quality in a noticeable way.
is a category of digital image compression types which possess the following characteristics. ° The original digital images can not be exactly reproduced as orginally acquired, but the changes may be visually inapparent. ° The compression algorithms can introduce artifacts into the images and affect post-decompression digital image processing. ° The prevalence of artifacts increases as the amount of compression increases or as the image detail content increas ° Much higher degrees of compression are possible than with lossless compression. es.
A term coined by graphics programmers to refer to a technique of shrinking file sizes by giving away some precision of detail. JPEG is an example of a file that is compressed this way. By reducing the so-called quality of a picture when you save it, you can make the file size smaller. Many photos can take of loss of fine detail before it becomes noticeable on a Web page.
File compression that radically reduces file size while discarding some data in the process. This is not always a problem because of image resolution on the web is generally low. (A jpeg is a lossy file format.)
A method of compression that attempts to discard unnecessary data. Some data loss can affect the quality of the image. JPEG uses this form of compression.
A compression scheme in which data is thrown away, resulting in loss of image quality. The degree of loss depends on the specific compression algorithm used.
A technique of reducing file size by discarding data. Once discarded, data can't be retrieved. Lossy compression techniques produce small files that don't need to be decompressed in a separate step before use, but the trade-off is some loss of quality.
A process for compressing data in which information deemed unnecessary is removed and cannot be recovered upon decompression. Typically used with audio and visual data in which a slight degradation of quality is acceptable. marker A text string that is associated with a designated time in Windows Media-based content. Markers often denote convenient points to begin playback, such as the start of a new scene.
This method results in a file that is close enough to the original to be useful. Since it produces a smaller compressed file than lossless compression, it's often used in streaming media to minimize file size and enable smooth transfer. MPEG compliant video streams use a very common form of lossy video compression.
reduces a file by permanently does away with certain information, especially unneeded information. When the file is uncompressed, only a part of the original information is still there (although the user may not notice it). Lossy compression is generally used for video and sound, where a certain amount of information loss will not be detected by most users. Last Reviewed: 2003-04-23
Data compression technique that dramatically reduces the size of a file by eliminating superfluous data. The lost information is either unnoticeable to the user, or can be recovered during decompression by extrapolation of the existing data. JPEG and MPEG are lossy methods that can reduce the size of graphics, audio, and video files by over 90%.
A compression technique that improves data reduction by discarding unnecessary image information.
A type of data compression which permanently discards data that humans supposedly "cannot hear" to create much smaller audio, video and image file sizes. When the file is decompressed by the recipient, this compression method replaces the data for the sections it removed with calculated values to restore the file. The decompressed file is similar but not identical to the original file.
A compression technique that sacrifices sound quality to make the file smaller.
Method of reducing video size in which extraneous image data is cut out to save space. Lossy compression is used when details are not crucial and when detail is subordinate to file size. For example, a home video containing images of your child eating probably does not need a high image quality when compared to a video containing images of a surgical operation, where details are important.
A compression technique in which some data is deliberately removed in order to achieve a greater reduction in compression.
A data compression method that sacrifices some information to achieve greater compression. This method is most often used for graphic and audio files. Such files may lose a bit of quality, but they usually remain understandable and take up far less storage space.
This is a way of saving a graphic file in a compressed format to reduce the file size, but at the cost of image quality. Jpegs can be saved at various levels of compression. The higher the compression, the smaller the file size, and the more image quality is lost.
A form of file compression that will compress data by a very great percentage. (10:1 to 20:1) However, when the data is un-compressed later, there will be data lost.
A form of compression in which image quality is degraded during compression.
Compression algorithms that throw out insignificant data in the compression process.
A type of file compression that results in the loss of image data every time the image is saved. JPEG is a lossy file format.
When a file compression system reduces the size of a file and is not capable of restoring it to precisely what it was before, then it is considered to be lossy (ie loses data!).
Lossy compression algorithms compress the image file by removing image details - usually the details that the eye does not perceive very well to start with.
In contrast to Lossless Compression, many multimedia files can be compressed using Lossy Compression formats so that even though the file, when it is uncompressed during playback, is not identical at the binary level to the original source file, we still find the results (hopefully) acceptable.
A compression technique that does not decompress data 100% back to original. Lossy compression provides high degrees of compression and results in very small compressed files, but there is a certain amount of loss when they are restored.
See compression ratio
A data compression technique in which some data is deliberately discarded in order to achieve massive reductions in the size of the compressed file. .........
A compression method that reduces the size of a file with varying or adjustable loss of data. JPEG is an example. Moiré – A pattern created by printing several repetitive designs on top of each other. In multi-color printing, screens of colored dots print on top of each other. If the angles of the halftone screens of each of the colors are not properly aligned with each other, an undesirable, blurry pattern called "moiré" appears in the final image.
A scheme that, after decompression, does not produce exactly the same data that was given to the compressor. Due to the nature of image data, the losses are often imperceptible to the human eye.
An electronic graphics compression equation that reduces file size, but also loses a small amount of image information. Lossy compression formats, like JPEG, are typically used for photographs, where slight information loss is not noticeable.
A process for compressing data in which information deemed unnecessary is removed and cannot be recovered upon decompression. Typically used with audio and visual data in which a slight degradation of quality is acceptable. MBR See definition for: multiple bit rate (MBR)
Compression techniques that achieve very high compression ratios by permanently removing data while preserving as much significant information as possible. Lossy compression includes perceptual coding techniques that attempt to limit the data loss to that which is least likely to be noticed by human perception.
Any compression method that allows only an approximate reconstruction of the original data. Common forms of JPEG fall into this class.
A type of compression that results in the loss of some of the original data. Lossy compression trades the potential loss of some image quality for the opportunity for greater compression. The JPEG baseline sequential and Cell methods are examples of lossy compression techniques. ( See also lossless compression.)
A process for compressing data in which information deemed unnecessary is removed and cannot be recovered upon decompression. Typically used with audio and visual data in which a slight degradation of quality is acceptable. See Also: lossless compression manual recording A click-to-record TV recording session in which Media Center records a particular service at a particular time. See Also: click-to-record , keyword recording , one-time recording , series recording
Lossy compression throws away information and reduces the level of detail from the original media.
compression in which some pixels are discarded, causing image or sound quality to degrade.
A data compression technique where the recovered data after decompression is different from the data that was compressed, though it will not be perceived as such by an observer.
See Data reduction
The technique of shrinking a media file by losing some precision of detail.
A data compression process in which the original data is not completely recoverable. For video or audio compression the lost data is usually either redundant or does not significantly impair the result. MPEG-2 is a lossy compression system.
compression comes with changes of digital information due to application of data reduction methods
This is a data compression technique; which results in data not being returned to its original form when it is decompressed. The benefit of using this technique is that it provides a high degree of compression, saving on storage space and transmission time over a network. See Lossless compression.
Compression that discards some of the data in video to minimize the storage space required. M-JPEG is an example.
A compression algorithm that reduces file size by actually removing data from the image. The post-compressed image is different from the pre-compressed image, even though they may look identical (visually lossless)
Compression that removes data so that the original cannot be precisely restored.
This compression method minimizes file size by eliminating unnecessary data, which causes a slight degradation of image quality.
A lossy data compression method is one where compressing a file and then decompressing it retrieves a file that may be different to the original, but is "close enough" to be useful in some way. This type of compression is used frequently on the Internet and especially in streaming media and telephony applications. ( http://en.wikipedia.org/wiki/Lossy_data_compression)
a compression method that reduces a digital file by permanently eliminating certain information (such as JPEG)
A method of image compression where some image quality is sacrificed in exchange for higher compression ratios. The amount of quality degradation depends on the compression algorithm used and a user selected quality variable.
A process by which an audio signal is examined from a human-psychoacoustic viewpoint. An algorithm attempts to estimate and remove the inaudible components of the signal. The remaining 'audible' component is efficiently coded in the output channel. Lossy compression schemes include MPEG audio, PASC, AC-3 and MUSICAM. The data recovered from a matched decoder is not identical to the original input, although it may sound very similar.
An image compression scheme that creates smaller files by discarding some image information. Repeated cycles of opening, modifying, and saving a file in this format leads to a loss of quality. JPEG is an example of a graphic format that uses a lossy compression scheme.
A data compression algorithm that actually reduces the amount of information in the data, rather than just the number of bits used to represent that information. The lost information is usually removed because it is subjectively less important to the quality of the data (usually an image or sound) or because it can be recovered reasonably by interpolation from the remaining data. A means for reducing the storage space required for an image. The decompressed image is not bit-for-bit identical to the original. Some details are lost or changed, although this might not be noticeable to the naked eye. MPEG and JPEG are examples of lossy compression techniques.
an irreversible way of reducing the size of data by approximating it
A compression algorithm that reduces file size by actually removing data from the image. The most effective lossy-compression algorithms work by discarding information that is not easily perceptible to the human eye. Effective compression ratios of 10:1 to 50:1 can be attained.
A compression format that cannot recover all of its original data from the compressed version. Supposedly some of what is normally recorded before compression is imperceptible, with the louder sounds masking the softer ones. As a result, some data can be eliminated since it's not heard anyway. This selective approach, determined by extensive psycho-acoustic research, is the basis for "lossy" compression. It is debatable however, how much data can actually be thrown away (or compressed) without an audible sacrifice. Dolby AC-3 and DTS are lossy compression schemes.
Refers to data compression techniques in which some amount of data is lost. Lossy compression technologies attempt to eliminate redundant or unnecessary information.
A file compression scheme that throws away image information in the process, thereby Compression leading to a degraded image.
A type of file compression in which files are reduced with parts of the image permanently removed. When considering this option, one must consider the chjoice of saving file space by making the file smaller and potentially losing detail, or leaving the file as a larger iimage size and retaining image quality.
A form of compression that attempts to discard unnecessary data. This data loss can affect the quality of the image. JPEG is a lossy file format.
Reduction in data bits using a system that predicts what should be, and what shouldn't be, 'audible' in a musical signal.
Reduces storage size of image by reducing the resolution and colour fidelity while maintaining minimum acceptable standard for general use.
Any method of data compression that reconstructs the original data approximately, rather than exactly.
In data compression, the case in which the decompressed information is different from the original uncompressed information. This mode is suitable for most continuous media, such as sound and motion video, as well as for many images. That the decompressed information is different from the original in lossy compression does not imply that the perceptual response of an observer is different. Also called irreversible compression.
Any compression method that sacrifices data in order to reduce file size. These types of compression often rely on the limits of human perception to work: the eye may not be able to tell the difference between an original image and one that has been compressed by limiting the number of colors used in it, or the ear might not notice when sounds above or below a certain frequency are removed from an audio track.
A method that makes files smaller by throwing away "unnecessary" information. JPG files use lossy compression. Repeated editing of images with lossy compression propagates error and degrades image quality.
A compression technique that will sacrifice some image quality at low levels and continue to degrade more image quality as compression levels increase.