DFT/RDFT filter bank approach for speckle reduction in SAR images

SEZGIN M. C., Erer I., ERSOY O.

25th IEEE International Geoscience and Remote Sensing Symposium (IGARSS 2005), Seoul, South Korea, 25 - 29 July 2005, pp.3689-3692 identifier identifier

  • Publication Type: Conference Paper / Full Text
  • Doi Number: 10.1109/igarss.2005.1526650
  • City: Seoul
  • Country: South Korea
  • Page Numbers: pp.3689-3692
  • Istanbul Technical University Affiliated: Yes

Abstract

A new speckle reduction algorithm based on subband decomposition is presented. The subband decomposition is performed using a DFT/RDFT-based symmetric, zero-phase, nonoverlapping digital filter bank. The SAR image is decomposed using the proposed filter bank structure and a threshold value is estimated according to noise variance in each subband, and used for soft thresholding. The despeckled image is obtained from the thresholded subband coefficients by a new perfect reconstruction algorithm. Experimental results show that the proposed method has competitive noise removal and detail preservation properties as compared to conventional approaches such as median filtering and wavelet transform based methods.