IMAGE ENHANCEMENT USING MULTI TIER NON LINEAR MONOTONIC FUNCTIONS

摘要

This invention provides an image enhancement method for low contrast or hazy image using multitier monotonic nonlinear function for sea scenario in real time. A monotonic piecewise nonlinear function for each tier has been derived in the dynamic range of 0 to 255. The values of nonlinear function are stored in the internal memory ROM of FPGA as a MIF file. The current pixel value of the digital video frame is used as an address of ROM. The ROM output data is used as final luminance digital video data. The nonlinear function is derived by changing the slope of each function, the slope of each function is varied in the fine and coarse way. The selection of proper nonlinear function among the multiple non-linear function is decided based on contrast level of video which is displayed on the screen. The selection of nonlinear function is operator selectable based on scenario. Figure 1