학술논문

Improved Chen-Smith image coder
Document Type
Conference
Source
1993 IEEE International Symposium on Circuits and Systems (ISCAS) Circuits and systems Circuits and Systems (ISCAS), 1993 IEEE International Symposium on. :267-270 vol.1 May, 1993
Subject
Components, Circuits, Devices and Systems
Communication, Networking and Broadcast Technologies
Engineered Materials, Dielectrics and Plasmas
Image coding
Discrete cosine transforms
Bit rate
Transform coding
Signal processing algorithms
Decoding
Bismuth
Quantization
Discrete transforms
Code standards
Language
Abstract
An image compression system based on transform coding and zonal sampling is presented. It is based on the Chen-Smith coder, but with an improved technique for transform coefficient quantization and the replacement of the discrete cosine transform (DCT) by the lapped orthogonal transform (LOT). The system leads to signal-to-noise ratios that are from 1.5 to 2.0 dB above those obtained with the standard JPEG algorithm, for a wide variety of test images and compression rates.ETX