An image-processing method for generating a customized image for a partial color deficient user over a display device, the image-processing method comprising: detecting a color for which a user is deficient in identifying the color, wherein the color is detected by displaying one or more images comprising a plurality of shades of the color to the user, wherein the plurality of shades comprise an increasing order of intensity of color; determining a spectrum of the color based upon the plurality of shades, wherein the spectrum comprises a start and an end, wherein the start indicates a shade at which the user fails to identify the color, and wherein the end indicates a shade at which the user identifies the color; identifying in an image used on the display device, color pixels corresponding to the spectrum, wherein the color pixels comprise Red Green Blue values; and replacing to generate the customized image, the RGB values of the color pixels with previously computed RGB values corresponding to: a black color; or a darker shade of said color, wherein the darker shade does not fall between the start and the end of the spectrum in order to generate a customized image capable of minimizing an operating power of the display device, wherein the operating power, consumed by the display device, is minimized up to a difference between powers consumed by a lower shade color pixel replacing the user color deficient pixels and the color pixel determining the end of the spectrum; and wherein the previously computed RGB values comprise lower RGB values than the RGB values of the color pixels. detecting a color for which a user is deficient in identifying the color, wherein the color is detected by displaying one or more images comprising a plurality of shades of the color to the user, wherein the plurality of shades comprise an increasing order of intensity of color; determining a spectrum of the color based upon the plurality of shades, wherein the spectrum comprises a start and an end, wherein the start indicates a shade at which the user fails to identify the color, and wherein the end indicates a shade at which the user identifies the color; identifying in an image used on the display device, color pixels corresponding to the spectrum, wherein the color pixels comprise Red Green Blue values; and replacing to generate the customized image, the RGB values of the color pixels with previously computed RGB values corresponding to: a black color; or a darker shade of said color, wherein the darker shade does not fall between the start and the end of the spectrum in order to generate a customized image capable of minimizing an operating power of the display device, wherein the operating power, consumed by the display device, is minimized up to a difference between powers consumed by a lower shade color pixel replacing the user color deficient pixels and the color pixel determining the end of the spectrum; and wherein the previously computed RGB values comprise lower RGB values than the RGB values of the color pixels. a black color; or a darker shade of said color, wherein the darker shade does not fall between the start and the end of the spectrum in order to generate a customized image capable of minimizing an operating power of the display device, wherein the operating power, consumed by the display device, is minimized up to a difference between powers consumed by a lower shade color pixel replacing the user color deficient pixels and the color pixel determining the end of the spectrum; and wherein the previously computed RGB values comprise lower RGB values than the RGB values of the color pixels.