Hyper-spectral image compression and encryption method

Abstract

The invention provides a hyper-spectral image compression and encryption method. The method comprises the following steps of performing coding in a wavelet transform three-dimensional set partitioning in hierarchical trees (3DSPIHT) coding way, simultaneously performing encryption, constructing a scrambling table in a Logistic mapping way to scramble an initial list of insignificant pixels (LIP), continuously iterating a Chen's model until all bits of data of significant types are encrypted, and in a decryption process which is the inverse operation of encryption, continuously updating an initial value of the Chen's model to decrypt the data of the significant types to make the decrypted data gradually approximate to an original image and finally reproduce the original image. According to the method, forward dependence of a 3DSPIHT coding method is utilized, and the data of the significant types is selectively encrypted in real time in a compression process, so that the encrypted data volume of the image is reduced, and the image transmission and encryption efficiency is improved; and the encrypted data volume of each significant type in a bit plane is calculated, and an initial key is scrambled after preprocessing, so that the sensitivity of the coding method to a plaintext is improved.

Description

technical field [0001] The invention relates to an image processing method, in particular to an image compression and decryption method. Background technique [0002] In recent years, various hyperspectral imaging technologies have been widely used in the fields of environmental monitoring, marine biology, geology, and military affairs. The hyperspectral imager obtains the continuous spectral information of each ground object while acquiring the target image. By integrating the spectral dimension information with the traditional image dimension, it can more accurately distinguish the ground object components. However, the amount of image data acquired by this technique is very large, and there is high spatial redundancy and inter-spectral redundancy. Therefore, seeking efficient hyperspectral image compression technology has received extensive attention. At present, for the compression of hyperspectral images, various prediction-based coding methods, vector quantization-ba...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to solve the problem of large amount of encrypted data and low encryption efficiency in the existing hyperspectral image encryption method, and propose a hyperspectral image based on a hierarchical number set partition method (3DSPIHT, 3D Set Partitioning in Hierarchical Trees) of 3D wavelet transform. Compression encryption method saves storage time and improves hyperspectral image transmission and encryption efficiency

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