Image-processing apparatus

An image processing apparatus configured to enlarge or reduce, in accordance with a set zooming ratio, inputted image data by calculating an interpolation pixel between input pixels included in the inputted image data,

• said image processing apparatus comprising:
• a reference block setting section configured to set a reference block including the interpolation pixel;
• an edge gradient direction setting section configured to set an edge gradient direction of the interpolation pixel by use of input pixels located within the reference block;
• a reference pixel setting section configured to set four reference pixels to be respective vertices of a quadrangle having two sides perpendicular to the edge gradient direction;
• a reference pixel value setting section configured such that, in a case where a first reference pixel of the four reference pixels is located outside the reference block, the reference pixel value setting section determines an intersection of a boundary line of the reference block and a side of the quadrangle including the first reference pixel, specifies, as adjacent input pixels, input pixels which are adjacent to the intersection and which are located within the reference block, and evaluates, based on distances between the intersection and the respective adjacent input pixels and based on pixel values of the respective adjacent input pixels, the first reference pixel value and, in a case where the first reference pixel is located inside the reference block, the reference pixel value setting section designates, as a reference pixel value, a pixel value of an input pixel located at the first reference pixel;
• a first interpolating section configured to calculate, by use of the reference pixel values of the respective four reference pixels, a first interpolation value which is a pixel value that depends on the edge gradient direction of the interpolation pixel;
• a second interpolating section configured to calculate, by use of interpolation that does not depend on the edge gradient direction of the interpolation pixel, a second interpolation value which is a pixel value that does not depend on the edge gradient direction of the interpolation pixel;
• a reliability calculating section configured to calculate reliability of the edge gradient direction of the interpolation pixel, which edge gradient direction is set by the edge gradient direction setting section;
• and
• a combining section configured to calculate a pixel value of the interpolation pixel by determining, based on the reliability, respective weight coefficients with respect to the first interpolation value and the second interpolation value and by adding, with use of the weight coefficients determined, the first interpolation value and the second interpolation value.