In this paper, the compression of visual information in the framework
of multimedia applications is discussed To this end, major approaches
to compress still as well as moving pictures are reviewed. The most im
portant objective in any compression algorithm is that of compression
efficiency. High-compression coding of still pictures can be split int
o three categories: waveform, second-generation, and fractal coding te
chniques. Each coding approach introduces a different artifact at the
tar-get bit rates. The primary objective of most ongoing research in t
his field is to mask these artifacts as much as possible to the human
visual system. Video-compression techniques have to deal with data enr
iched by one more component. namely, the temporal coordinate. Either c
ompression techniques developed for still images can be generalized fo
r three-dimensional signals (space and time) or a hybrid approach can
be defined based on motion compensation. The video-compression techniq
ues can then be classified into the following four classes: waveform,
object-based, model-based, and fractal coding techniques. The aim of t
his paper is to provide the reader with a tutorial on major visual dat
a-compression techniques and a list of references for further informat
ion on the details of each method.