This function uses the window/level mapping method to change the contrast of an 9-16-bit image.

Declaration:

AT_ERRCOUNT ACCUAPI MED_display_contrast_double(
        HIGEAR hIGear, 
        const DOUBLE rescale_slope, 
        const DOUBLE rescale_intercept, 
        const DOUBLE window_center, 
        const DOUBLE window_width, 
        const DOUBLE gamma
);

Arguments:

Return Value:

Returns the number of ImageGear errors that occurred during the function call.

Supported Raster Image Formats:

Grayscale – 8…32 bpp.

Remarks:

It takes values for Window Center & Width, and Rescale Slope & Intercept, and it also allows you to apply Gamma correction, if you desire.

This function fills the 16x8 LUT with values that will display a 9-16 bit image according to VOI LUT (Window Center/Width) and Modality LUT (Rescale Intercept/Slope) values that you specify. Any values that have been in the 16x8 LUT are overwritten with these new ones.

If the Rescale Slope and Intercept of the image are known, you should provide them. If they are not known, pass in a 1.0 and 0.0, respectively.

If you do not have values for Window Center and Window Width, these can be calculated using the minimum and maximum pixel values (if you have them known). Here are the formulas you should use to display all pixel values:

Window Center = (max + min) / 2;

Window Width = (max - min);

This function does not cause the image to be displayed or repainted. It only fills the 16x8 LUT. To display the results of this function, use IG_dspl_image_draw().

See also MED_display_contrast_auto_double()