Hierarchical Transmission of DCT Coefficients Using Multi-Code DS/SS Modulation
Masaru Honjo, Satoshi Makido, Takaya Yamazato, Hiraku Okada, Masaaki Katayama, Akira Ogawa · IEICE Transactions on Fundamentals of Electronics Communications and Computer Sciences · 2004
We propose a novel hierarchical transmission method of DCT coefficients using multi-code DS/SS modulation. For low resolution image transmission over noisy channel, an error resilient and graceful degradation technique isnecessary. Here, the DCT coefficients are divided into each stratum (a branch of multi-code DS/SS) and transmitted simultaneously through a noisy channel. By assigning an appropriate transmission energy that corresponds to their source energy variances, energy assignment, it is possible to maintain picture quality effectively even in a noisy channel. Analysis of this method was performed using an image data model, 2-D Gauss-Markov random field, which showed that picture quality is maintained even in the noisy channel condition.