Wavelet Fractal Coding of Radar Image for VDR Storage
Fuxing Li, Chaojian Shi, Keping Guan · 2012
Voyage Data Recorder (VDR) plays an important role in determining responsibility for marine accidents. Most of its capacity stores the shipboard navigation radar images. Thus, according to the characteristics of ship-borne radar images, on the premise of ensuring the quality of the compression and playback, maximizing the compression ratio is one of the ways to improve VDR storage capacity. A wavelet fractal coding algorithm is proposed for this purpose. Integer wavelet transform is applied to decompose and reconstruct radar image, and then modified fast fractal coding is used to encode low-frequency sub-image. The VDR radar images compression experiments show that the algorithm improves the compression speed and compression ratio.