lossy compression


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Related to lossy compression: Lossless compression

lossy compression

A compression technique that does not decompress digital data back to 100% of the original. Lossy methods can provide high degrees of compression and result in smaller compressed files, but some number of the original pixels, sound waves or video frames are removed forever. Examples are the widely used JPEG image, MPEG video and MP3 audio formats.

The greater the compression, the smaller the file. However, a high image compression loss can be observed in photos printed very large, and people with excellent hearing can notice a huge difference between MP3 music and high-resolution audio files (see audiophile). Typically, the moving frames of video can tolerate a greater loss of pixels than still images.

Lossy compression is never used for business data and text, which demand a perfect restoration (see lossless compression). See data compression, codec examples, JPEG, MPEG and MP3.


Lossless Vs. Lossy Compression
Business data requires lossless compression, while audio and video applications can tolerate some loss, which may not be very noticeable.







Sometimes Hard to Tell
The top JPEG image is one fifth the file size of the bottom image, which was compressed the least. Look carefully at the orange section on the top of this cake.


Sometimes Hard to Tell
The top JPEG image is one fifth the file size of the bottom image, which was compressed the least. Look carefully at the orange section on the top of this cake.







Easier to See With Text
The top JPEG image was compressed the most, and the text is not as sharp as the least compressed. The bottom blow-up shows the distortion clearly.


Easier to See With Text
The top JPEG image was compressed the most, and the text is not as sharp as the least compressed. The bottom blow-up shows the distortion clearly.


Easier to See With Text
The top JPEG image was compressed the most, and the text is not as sharp as the least compressed. The bottom blow-up shows the distortion clearly.







Lossless GIFs Are Better for Text
The same text is saved in the lossless GIF format. Not only is it as sharp as the least-compressed JPEG, the GIF file is almost 1/10th the size.


Lossless GIFs Are Better for Text
The same text is saved in the lossless GIF format. Not only is it as sharp as the least-compressed JPEG, the GIF file is almost 1/10th the size.
References in periodicals archive ?
Given the data volume challenge we face, we should consider the wider use of more aggressive data compression techniques, such as lossy compression, as a matter of course.
As one more option of DI lossy compression implementation we will consider a way which is not the accepted standard, but it is often used during the work with images [10].
Lossless and lossy compression technique is applied on ROI and non-ROI parts respectively (Kaur et al.
8) In addition to lossy compression, there is also often loss of information during transmission or retrieval.
The distortion in the lossy compression determines the coarseness of the segmentation and its optimal value may differ for each image.
JPEG2000 is a transform-based compression algorithm, intended for both lossless and lossy compression of images.
Basic ideas of lossless and lossy compression algorithms are covered.
Samplify provides real-time lossless and lossy compression solutions for high-speed sampled data systems.
It is a low-complexity, real-time lossless and lossy compression algorithm that provides the flexibility, scalability, and cost advantages attractive for medical imaging systems.
When a study is compressed using lossy compression, no clinically significant data is lost; however, the original information cannot be completely reconstituted.
The best way to minimize the effect of lossy compression is to make sure that, after hitting Save As, set the Quality under Image Options to Max.
Lossy Compression Compression is lossy if the original file cannot be perfectly recovered from the compressed file; the goal is to get the best possible quality for the given compression.