Video/graphics text mode enhancement method for digitally processed data

Abstract

A text enhancement unit is introduced in order to alleviate the degradation of text characters on computer or television displays. The text enhancement unit uses an enhancement process to regain uniformity and intensity that may be lost during image processing. The text enhancer unit may be placed between an image processing unit such as a scaler, de-interlacer, or DSP, and a computer or television display to improve the quality of text characters that may have become degraded by image processing performed by the image processing unit. In one embodiment, the text enhancer unit improves contrast by multiplying pixel intensity by an intensity multiplier. In a second embodiment, the text enhancer unit improves contrast using a threshold operation which outputs either a very high or very low intensity pixel. In an third embodiment, the text enhancer unit improves contrast using a threshold operation which outputs either a very low intensity pixel or a pixel multiplied by an intensity multiplier. In a fourth embodiment, the text enhancer unit improves contrast using a threshold operation which outputs either an unchanged pixel or a pixel multiplied by an intensity multiplier. In a fifth embodiment, the text enhancer unit improves contrast using a dual threshold operation which outputs either a very low intensity pixel, a very high intensity pixel, or an unchanged pixel.