Metodo para Restauracao e Reamostragem de Imagens do Sensor TM (Method for Restoration and Resampling of TM Sensor Imagery)

摘要

Some results obtained with the restoration for resampling TM images using techniques designed in the Fourier domain and implemented in the spatial domain are presented. The main idea is to obtain a good approximation for the original image over a finer grid, by substituting conventional interpolation techniques by the restoration technique. Therefore, image data with slightly better spatial and radiometric quality than the raw data can be synthesized with the resampling process. The work involves the design of a linear restoration filter with input and output defined on different sampling grids. The filter is designed in the Fourier domain by using the technique of compensation of the transfer function. Subsequently, a linear operator in the spatial domain is derived to be applied in the image restoration process. The restoration filter is applied to resample images from the TM sensor of the LANDSAT-5 on a 15 m sampling grid. These restored images are compared to the images that were resampled with the parametric cubic convolution. The comparison is made in visual terms, through the radiometric profile along on image line, through the difference between the images and through statistical measures, indicating better results with the proposed method.