Method for making look-up tables for video format converter using the look-up tables

A scan format converter using bi-sigmoid interpolation, comprising:

• a memory controller having a look-up table at which first and second displacement values for pixel points of a video format to be converted are stored, for controlling transmission of color signals input from an external device, and reading the first and second displacement values for the pixel points of the color signals from said look-up table;
• a memory for temporarily storing said color signals;
• a color signal logic circuit having a plurality of bi-sigmoid interpolation tables at which sigmoid interpolation values according to a color signal level difference between two pixel points are stored, for bi-sigmoid-interpolating the color signal levels of the input pixel points with respect to an x-axis and a y-axis according to the first and second displacement values input from said memory controller;
• and
• a sync generator for generating a sync signal to said color signal logic circuit.

A scan format converter for converting a video format by bi-sigmoid interpolation, comprising:

• a memory controller having a look-up table at which first and second displacement values for pixel points of a video format to be converted are stored, for controlling transmission of color signals input from an external device, and reading the first and second displacement values for the pixel points of the color signals from said look-up table;
• a mode detector for detecting horizontal and vertical sync signals input from the external device and outputting a video format detection signal representing a mode of the currently input video format to the memory controller;
• a memory for temporarily storing said color signals;
• a color signal logic circuit having a plurality of bi-sigmoid interpolation tables at which sigmoid interpolation values according to a color signal level difference between two pixel points are stored, for bi-sigmoid-interpolating the color signal levels of the input pixel points with respect to an x-axis and a y-axis according to the first and second displacement values input from said memory controller;
• and
• a sync generator for generating a sync signal to said color signal logic circuit.