Glossary
Data Compression
The process of reducing the number of bits required to store or transmit digital data.
Example:
When you download a large game, it's often delivered in a compressed format, demonstrating data compression in action to save bandwidth and storage.
Hybrid Approaches
Data compression methods that combine elements of both lossless and lossy compression techniques to optimize for specific use cases.
Example:
A modern video codec might use hybrid approaches, applying lossy compression to the visual frames while using lossless compression for certain metadata or audio tracks.
LZW Compression Algorithm
A lossless data compression algorithm that replaces repeating patterns of data with shorter codes or symbols, building a dictionary of these patterns.
Example:
When you view a GIF image, it often utilizes the LZW Compression Algorithm to efficiently store its pixel data by referencing common color patterns.
Lossless Compression
A type of data compression where no information is lost during the compression process, allowing the original data to be perfectly reconstructed.
Example:
Saving a text document as a ZIP file uses lossless compression, ensuring that every character remains exactly the same when the file is unzipped.
Lossy Compression
A type of data compression that permanently removes some data to achieve a significantly smaller file size, often by discarding information imperceptible to humans.
Example:
Streaming music on platforms like Spotify often employs lossy compression (e.g., MP3) to reduce file size, making playback smoother even if some audio detail is sacrificed.
Redundancy
The presence of repeated or unnecessary information within a data set that can be removed without losing essential content.
Example:
In a black and white image, a large block of identical black pixels represents redundancy that can be efficiently compressed.
Run-Length Encoding
A lossless data compression algorithm that replaces sequences of identical consecutive data values with a count and the value itself.
Example:
If a simple graphic contains a long line of 20 blue pixels, Run-Length Encoding would store it as '20B' instead of listing 'B' twenty times.