一种适于空间多光谱TDICCD图像压缩算法

针对传统遥感图像压缩算法中小波变换和位平面编码没有考虑图像内容特点而导致多光谱各谱段图像边缘和纹理的模糊的问题，提出一种适于成像谱段数相对较少多光谱TDICCD图像压缩算法。提出的自适应提升DWT可以自适应的选择最佳的提升方向，同时根据图像局部特征使用拉格朗日插值策略进行预测，这种方法可以充分的利用图像的纹理信息。提出的码率控制算法可以根据图像纹理复杂程度进行自适应的码率分配。实验结果表明，提出的压缩算法具有良好压缩性能，对于平滑的图像与传统算法相当，对于边缘和纹理程度复杂的图像，性能高于传统算法，在正常工作压缩比为8∶1时，平均信噪比比传统方法平均提高了3.53 dB。有效的保护了多光谱图像的边缘和纹理信息，非常适于纹理复杂的空间多光谱CCD图像压缩应用。

A Compression Algorithm for Multi-Spectral TDICCD Image

In order to solve the problem of edge and texture blurring of multi-spectral image caused by the wavelet transform and bit-plane encoder of traditional method not taking into account image characteristics, a compression algorithm of multi-spectral TDICCD image having few bands is proposed in the present paper. The proposed direction-adaptive lifting DWT can adaptively choose the best lifting direction and use the Lagrange interpolation technique to make prediction according to its local characteristics. This method makes good use of the image texture features. The proposed rate control algorithm can adaptively allocate the rate bits according to image content. The experiments results showed that the proposed compression algorithm has good compressive property. Compared with traditional approaches, the performance of our method corresponds to the conventional approach for smooth images. However, it was superior to others for images with rich texture and a large number of edge detail information. In the compression ration 4∶1, the average peak signal to noise ratio of the proposed compression algorithm could improve the average PSNR by 1.939 dB. They effectively protect the edge and texture detail information for multi-spectral image. It is very suitable for the application of space multi-spectral CCD image with rich texture and a large number of edge detail information.