Lossy compression
Class of data compression methods that uses inexact approximations and partial data discarding to represent the content.
- Lossy compression257 related topics
JPEG
JPEG is a commonly used method of lossy compression for digital images, particularly for those images produced by digital photography.
Lossless compression
Class of data compression that allows the original data to be perfectly reconstructed from the compressed data with no loss of information.
By contrast, lossy compression permits reconstruction only of an approximation of the original data, though usually with greatly improved compression rates (and therefore reduced media sizes).
Data compression
Process of encoding information using fewer bits than the original representation.
Any particular compression is either lossy or lossless.
Quantization (signal processing)
Process of mapping input values from a large set to output values in a (countable) smaller set, often with a finite number of elements.
Quantization also forms the core of essentially all lossy compression algorithms.
Video
Electronic medium for the recording, copying, playback, broadcasting, and display of moving visual media.
Practical digital video was made possible with discrete cosine transform (DCT) coding, a lossy compression process developed in the early 1970s.
MP3
Coding format for digital audio developed largely by the Fraunhofer Society in Germany, with support from other digital scientists in the United States and elsewhere.
With regard to audio compression (the aspect of the standard most apparent to end-users, and for which it is best known), MP3 uses lossy data-compression to encode data using inexact approximations and the partial discarding of data.
Advanced Video Coding
Video compression standard based on block-oriented, motion-compensated coding.
H.264 is typically used for lossy compression, although it is also possible to create truly lossless-coded regions within lossy-coded pictures or to support rare use cases for which the entire encoding is lossless.
Image compression
Type of data compression applied to digital images, to reduce their cost for storage or transmission.
Image compression may be lossy or lossless.
Nasir Ahmed (engineer)
Indian and American electrical engineer and computer scientist.
The discrete cosine transform (DCT) is a lossy compression algorithm that was first conceived by Ahmed while working at the Kansas State University, and he proposed the technique to the National Science Foundation in 1972.
Codec
Device or computer program which encodes or decodes a data stream or signal.
Compression codecs are classified primarily into lossy codecs and lossless codecs.