Patent ID: 9014502
Filing Date: 2015-04-21
Classification: G06T,H04N

Abstract:
1. A signal processing device that performs processing to sharpen an image represented by an input signal and outputs an output signal that represents the sharpened image, comprising: a signal interpolation circuit configured to generate an interpolated signal by performing signal interpolation on the input signal; a sharpening circuit to which the interpolated signal is inputted and configured to generate a sharpened signal in which high band frequency components in the interpolated signal are nonlinearly monotonically increased; and a signal thinning circuit to which the sharpened signal is inputted and configured to generate a downsampled signal by thinning a signal from the sharpened signal, wherein the downsampled signal is outputted as the output signal, the sharpening circuit further includes: a low frequency component removal circuit configured to generate a low-frequency-removed signal by removing low frequency components which include at least direct current components, from frequency components included in the interpolated signal; a nonlinear processing circuit configured to generate a nonlinearly processed signal (i) which is identical in sign to the low-frequency-removed signal and (ii) which is non-linearly monotonically increased with respect to the low-frequency-removed signal in a case where a value of the low-frequency-removed signal is at least near zero; and an addition circuit configured to generate an addition signal by adding the nonlinearly processed signal to the interpolated signal and output the addition signal as the sharpened signal.