Patent ID: 6753862
Filing Date: 2004-06-22
Classification: G06F,G09G

Abstract:
A method of smoothing an outline of a character image of a bitmapped font defined by bitmap data in a dot matrix format,the method comprising the steps of: determining coordinates of a starting point of said bitmap data, according to predetermined conditions, said starting point being associated with a start of vector data into which said bitmap data is converted while referring to vectorized dot information indicative of whether or not each dot of said bitmap data has been vectorized; converting said bitmap data to an orthogonal vector sequence by sequentially determining a direction of each adjacent dot of said bitmap data which is located next to a corresponding preceding dot, starting from said starting point, according to a predetermined order, and converting said each adjacent dot of said bitmap data into a vector of a direction of any of upward, downward, leftward, and rightward directions, with reference to said determined direction, while at the same time updating said vectorized dot information; converting said orthogonal vector sequence to a diagonal vector sequence based on each sequence of a predetermined number of vectors of said orthogonal vector sequence, with reference to a diagonalization table defining in advance predetermined patterns of said each of sequence which is to be applied for converting a vector of said diagonal vector sequence to a diagonal vector; carrying out line-drawing processing by producing bitmap coordinate points based on said starting point and said diagonal vector sequence and correcting said bit map coordinate points with reference to a correction data table defining in advance amounts of correction in units of dots in a manner associated with respective patterns of each sequence of a predetermined number of vectors of said diagonal vector sequence; causing aforementioned steps to be repeatedly carried out until the step of determining said coordinates of a starting point can determine no more starting point, to thereby produce line data representative of results of said line-drawing processing; and producing new bitmap data based on said line data; wherein the step of carrying out line-drawing processing includes producing data defining an outline of said character image and data defining a line for filling an inside thereof with dots by filling processing, and wherein the step of producing new bitmap data comprises the steps of: carrying out said filling processing; superposing data obtained by said filling processing and said data defining said outline one upon another; and carrying out stroke width-reducing processing for reducing a stroke width of said character image increased due to said vectorization.