结合光谱解混与压缩感知的高光谱图像有损压缩

Compressive-sensing-based lossy compression for hyperspectral images using spectral unmixing

  • 摘要: 压缩传感技术可以利用远少于奈奎斯特采样定理所获得的采样数据进行信号的鲁棒性重建。因此,该技术在计算资源和存储空间均受限的高光谱图像压缩中具有很大的应用潜力。提出了一种基于压缩感知与光谱解混的高光谱图像压缩算法。在编码端,分别通过空间采样和光谱采样来实现图像采样点的压缩;然后,对采样数据的空间与谱间相关性进行了研究。为了提高压缩性能,采用谱线性预测去除采样后的谱间相关性,利用JPEG-LS对预测误差进行编码来生成最终的比特流。在解码端,首先解码比特流以获得采样数据;采用光谱解混技术对原始高光谱图像进行重构,克服了传统压缩感知重建的诸多不足。针对机载可见/红外成像光谱仪数据的实验结果表明,该算法比JPEG2000和DCT-JPEG2000具有更好的压缩性能,并具有较低的计算复杂度。

     

    Abstract: In the compressive sensing theory, the robust reconstruction of signals can be obtained from far fewer measurements than those obtained by the Nyquist theorem. Thus, it has a great potential in the onboard compression of hyperspectral images using minimal computational resources and storage memory. In this paper, a compressive-sensing-based hyperspectral image compression method was presented using spectral unmixing. At the encoder, the original image was compressed acquired by spatial sampling and spectral sampling, respectively. Then, the spectral and spatial correlation of the compressed data were studied. To improve the compression performance, spectral linear prediction was used to remove the spectral correlation, and the predictive errors were compressed by JPEG-LS in a lossless manner to generate the final bit-streams. At the decoder, the bit-streams were first decoded to obtain the sampled data. Then, a spectral unmixing technique was employed to reconstruct the original hyperspectral image, which can avoid the defect of conventional compressed sensing reconstruction. Experiments on data from the Airborne Visible/Infrared Imaging Spectrometer sensor show that the proposed algorithm provides better compression performance than JPEG2000 and DCT-JPEG2000 with a lower computational complexity.

     

/

返回文章
返回