Noise Measurement

We propose a new hierarchical approach to resolution scalable lossless and near-lossless (NLS) compression. It combines the adaptability of DPCM schemes with new hierarchical oriented predictors to provide resolution scalability with better compression performances than the usual hierarchical interpolation predictor or the wavelet transform. Because the proposed hierarchical oriented prediction (HOP) is not really efficient on smooth images, we also

To improve interference robustness of wireless communication, spread spectrum techniques are often used. We use the chirp spreading technique along with FSK and PSK binary modulation schemes to obtain interference robust radio communication. The performance of chirped-FSK and chirped-PSK modulation through a white gaussian noise channel is simulated assuming a synchronized clock between transmitter and the receiver. We analyzed and simulated the error probability (BER) of the overall system in the presence of partial band of interference in the channel. The simulated BER is close to the estimated BER and they prove the superior performance of chirp-based modulation in the presence of interference.

Abstract. In this contribution we present experiments on color image enhancement for several dierent non-linear lters which originally were de ned for gray-level images. We disturb sample images by dierent types of noise and measure performance of the lters. We provide signal-to-noise measurements as well as perceived color dierence in E as dened by the CIE. All images and test programs are provided online on the internet so that experiments can be validated by arbitrary users on any image data.