Patent ID: 7106386
Filing Date: 2006-09-12
Classification: H04N

Abstract:
1. A picture quality improvement device, said device having a two-dimensional low-pass filter for taking as input a luminance signal that is obtained from a video signal and extracting low-pass components of said input luminance signal for a vertical direction and a horizontal direction of an image that is displayed by means of said video signal; and said device adding an edge signal, which is obtained by subtracting said low-pass components that are extracted by said two-dimensional low-pass filter from said luminance signal, to said luminance signal; wherein said two-dimensional low-pass filter is constituted such that extracted gain of the low-pass component of the vertical direction and the extracted gain of the low-pass component of the horizontal direction can be individually adjusted according to a magnification of enlargement of said image; and wherein said two-dimensional low-pass filter comprises: a vertical low-pass filter for extracting a low-pass component of the vertical direction of an input luminance signal; a vertical delay unit for receiving as input said input luminance signal that has been branched and delaying said input luminance signal that has been branched and received by a prescribed delay time interval; a vertical gain adjustment means for obtaining, from the low-pass component of the vertical direction that has been extracted by said vertical low-pass filter and a delayed luminance signal that has been delayed by said vertical delay unit, a vertical low-pass component that has undergone gain adjustment to become a prescribed gain; a horizontal low-pass filter for receiving as input a luminance signal that is outputted from said vertical gain adjustment means and from which said vertical low-pass component has been extracted and extracting a low-pass component of the horizontal direction of said input luminance signal; a horizontal delay unit for receiving as input the luminance signal that is outputted from said vertical gain adjustment means and branched and delaying the input luminance signal that has been branched and received by a prescribed delay time interval; and a horizontal gain adjustment means for obtaining, from the low-pass component of the horizontal direction that has been extracted by said horizontal low-pass filter and a delayed luminance signal that has been delayed by said horizontal delay unit, a horizontal low-pass component that has undergone gain adjustment to become a prescribed gain.