Image reconstruction of millimeter-wave radiometers with multi-quadric splines

We present in this work a robust method to reconstruct millimeter-wave images from passive sensors. The method estimates each pixel of the image by applying a locally adaptive smoothing filter to the samples of the sensor. The filter assigns for each sample in the neighborhood of the pixel under consideration a weighting factor that determines its contribution. The filter preserves the piecewise smoothness of the image since it applies the multi-quadric splines combined with some adaptive distances to smooth the samples while preserving the edges. Results show that the our scheme leads to more contrast, less noise and the shape of the objects are better preserved in the constructed images when compared to state of the art methods.