In order to develop techniques that manipulate data using mathematical operations, we need to have a mathematical model for the data. Obviously, the better the model (i.e., the closer the model matches the aspects of reality that are of interest to us), the more likely it is that we will come up with a satisfactory … Read more
Models for certain telemetry data can also be obtained through knowledge of the under-lying process. For example, if residential electrical meter readings at hourly intervals were to be coded, knowledge about the living habits of the populace could be used to determine when electricity usage would be high and when the usage would be low. … Read more
Although the idea of a quantitative measure of information has been around for a while, the person who pulled everything together into what is now called information theory was Claude Elwood Shannon. An electrical engineer at Bell Labs. Shannon defined a quantity called self-information. Suppose we have an event A, which is a set of … Read more
A compression algorithm can be evaluated in a number of different ways. We could measure the relative complexity of the algorithm, the memory required to implement the algorithm, how fast the algorithm performs on a given machine, the amount of compression, and how closely the reconstruction resembles the original A very logical way of measuring … Read more
The development of data compression algorithms for a variety of data can be divided into two phases. The first phase is usually referred to as modeling. In this phase we try to extract information about any redundancy that exists in the data and describe the redundancy in the form of a model. The second phase … Read more
Huffman coding shares most characteristics of Shannon-Fano coding. It creates variable-length codes that are an integral number of bits. Symbols with higher probabilities get shorter codes. Huffman codes have the unique prefix attribute, which means they can be correctly decoded despite being variable length. Decoding a stream of Huffman codes is generally done by following … Read more
Data Compression= Modeling + Coding in general, data compression consists of taking a stream of symbols and transforming them into codes. If the compression is effective, the resulting stream of codes will be smaller than the original symbols. The decision to output a certain code for a certain symbol or set of symbols is based … Read more
Compression techniques are methods employed to reduce the size of data or files, making them more manageable for storage, transmission, and processing. These techniques are crucial in various fields, including data storage, network communication, and multimedia applications. Here are some common compression techniques: 1. Lossless Compression: Lossless compression retains all the original data when the … Read more