Video on the Internet: An introduction to the digital encoding, compression, and transmission of moving image data

In this paper, we seek to provide an introduction to the fast-moving field of digital video on the Internet, from the viewpoint of the biological micr oscopist who might wish to store or access videos, for instance in image da tabases such as the BioImage Database (http://www.bioimage.org),We describe and evaluate the principal methods used for encoding and compressing movin g image data for digital storage and transmission over the Internet, which involve compromises between compression efficiency and retention of image f idelity, and describe the existing alternate software technologies for down loading or streaming compressed digitized videos using a Web browser. We re port the results of experiments on video microscopy recordings and three-di mensional confocal animations of biological specimens to evaluate the compr ession efficiencies of the principal video compression-decompression algori thms (codecs) and to document the artefacts associated with each of them. B ecause MPEG-1 gives very high compression while yet retaining reasonable im age quality, these studies lead us to recommend that video databases should store both a high-resolution original version of each video, ideally eithe r uncompressed or losslessly compressed, and a separate edited and highly c ompressed MPEG-1 preview version that can be rapidly downloaded for interac tive viewing by the database user. (C) 1999 Academic Press.