Abstract This paper introduces a robust and secure data hiding scheme to transmit grayscale image in encryption-then-compression domain. First, host is transformed using lifting wavelet transform, Hessenberg decomposition redundant singular value decomposition. Then, we use appropriate scaling factor invisibly embed the of watermark into lower frequency sub-band image. We also suitable improve ...

A transient electromagnetic signal is recorded in an earth formation while drilling at multiple times. Data for subsequent interpretation transmitted via a hydrochannel with narrow bandwidth, that reason the amount of information limited. Therefore, data compression indispensable element processing. It important to determine what parameters and how many them are necessary describe measured EMF ...