Lossy Image Coding with the Quantization Based on Graycode

DOI Web Site 15 References

Bibliographic Information

Other Title
  • グレイコードに基づく量子化を用いた非可逆画像符号化
  • グレイコード ニ モトヅク リョウシカ オ モチイタ ヒカギャク ガゾウ フゴウカ

Search this article

Abstract

This paper presents a new quantization technique based on the characteristics of graycode, and a new technique of lossy image coding, which is composed of predictive coding, wavelet transform and the quantization technique. Graycode is a code in which codes for two natural numbers whose difference equals one differ only at one bit from each other. When a bit of graycode of a value is changed, the average of the original value and the changed value can be represented by more significant bits above the changed bit. In the quantization technique, values to be encoded are quantized so that their acceptable quantization error ranges are fixed. The quantized values are encoded with quadtree and arithmetic coding. Experiments were performed in which the proposed technique was compared with JPEG and JPEG2000 in respect of compression ratio and image quality. It was shown that the proposed technique gives better quality than JPEG when the predictive coding is employed. If the target quality of images is high, the proposed technique gives equal or better quality compared to JPEG2000 when the wavelet transform is also used.

Journal

References(15)*help

See more

Keywords

Details 詳細情報について

Report a problem

Back to top