Patent ID: 8437040
Filing Date: 2013-05-07
Classification: H04N

Abstract:
1. A computer-implemented method for controlling a tone reproduction curve (TRC) of an image printing system, wherein the method is implemented in a computer system comprising one or more processors configured to execute one or more computer program modules, the method comprising: printing a printed image by forming a toner image on an image transfer surface based on input image data and transferring the toner image to an output media to form the printed image; measuring, during the printing of the printed image, the toner image on the image transfer surface using an image transfer surface sensor to obtain toner image data, wherein the toner image data comprises a set of image transfer surface contone values representative of an area coverage of the toner image on the image transfer surface; controlling the toner image data to achieve a target image transfer surface tone reproduction curve; measuring the printed image on the output media using a printed image sensor to obtain printed image data, wherein the printed image data comprises a set of print contone values representative of an area coverage of the printed image on the output media; generating an actual printed image tone reproduction curve using the printed image data; determining a set of adjusted contone values by comparing the actual printed image tone reproduction curve with a target printed image tone reproduction curve, the adjusted contone values being representative of the print contone values at which target color density data of the printed image is achieved in the image printing system; determining adjusted image transfer surface reflectance data to update the target image transfer surface tone reproduction curve, the adjusted image transfer surface reflectance data being obtained by interpolating the target image transfer surface tone reproduction curve at the adjusted contone values; and controlling subsequent toner image data from the image transfer surface sensor to achieve the updated target image transfer surface tone reproduction curve.