Prefix codes for this task are generated by an algorithm that examines strings and builds a (*) tree.
The PNG format was developed after a brouhaha erupted between CompuServe and Unisys over an algorithm that performs this task. Many algorithms for this task use discrete cosine transforms to convert a signal into the frequency domain, and then discard components of the signal above a desired threshold. Prefix codes for this task are generated by an algorithm that examines strings and builds a (*) tree. In the Linux operating system, the output of this task may be a tarball. The LZW algorithm and Huffman coding are examples of the "lossless" type of this process. "Lossy" examples of this process include creating JPEGs and MP3s. For 10 points, name this process of reducing the amount of data needed to specify a file, which is often done to an image or music.
The PNG format was developed after a brouhaha erupted between CompuServe and Unisys over an algorithm that performs this task.
compression  [accept word forms; prompt on en coding  or en code ]