enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Discrete cosine transform - Wikipedia

    en.wikipedia.org/wiki/Discrete_cosine_transform

    Uncompressed digital media as well as lossless compression have high memory and bandwidth requirements, which is significantly reduced by the DCT lossy compression technique, [7] [8] capable of achieving data compression ratios from 8:1 to 14:1 for near-studio-quality, [7] up to 100:1 for acceptable-quality content. [8]

  3. Data compression - Wikipedia

    en.wikipedia.org/wiki/Data_compression

    In both lossy and lossless compression, information redundancy is reduced, using methods such as coding, quantization, DCT and linear prediction to reduce the amount of information used to represent the uncompressed data. Lossy audio compression algorithms provide higher compression and are used in numerous audio applications including Vorbis ...

  4. Lossless join decomposition - Wikipedia

    en.wikipedia.org/wiki/Lossless_join_decomposition

    In database design, a lossless join decomposition is a decomposition of a relation into relations , such that a natural join of the two smaller relations yields back the original relation. This is central in removing redundancy safely from databases while preserving the original data. [ 1 ]

  5. Lossy compression - Wikipedia

    en.wikipedia.org/wiki/Lossy_compression

    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 [5] – for example, in principle, if one starts with an analog or high-resolution digital master, an MP3 file of a given size should provide a better ...

  6. LZ4 (compression algorithm) - Wikipedia

    en.wikipedia.org/wiki/LZ4_(compression_algorithm)

    The Apache Hadoop system uses this algorithm for fast compression. LZ4 was also implemented natively in the Linux kernel 3.11. [ 9 ] The FreeBSD, Illumos, ZFS on Linux, and ZFS-OSX implementations of the ZFS filesystem support the LZ4 algorithm for on-the-fly compression.

  7. Transform coding - Wikipedia

    en.wikipedia.org/wiki/Transform_coding

    Transform coding is a type of data compression for "natural" data like audio signals or photographic images.The transformation is typically lossless (perfectly reversible) on its own but is used to enable better (more targeted) quantization, which then results in a lower quality copy of the original input (lossy compression).

  8. Asymmetric numeral systems - Wikipedia

    en.wikipedia.org/wiki/Asymmetric_numeral_systems

    Asymmetric numeral systems (ANS) [1] [2] is a family of entropy encoding methods introduced by Jarosław (Jarek) Duda [3] from Jagiellonian University, used in data compression since 2014 [4] due to improved performance compared to previous methods. [5]

  9. Entropy coding - Wikipedia

    en.wikipedia.org/wiki/Entropy_coding

    In information theory, an entropy coding (or entropy encoding) is any lossless data compression method that attempts to approach the lower bound declared by Shannon's source coding theorem, which states that any lossless data compression method must have an expected code length greater than or equal to the entropy of the source. [1]