METHODS AND APPARATUSES FOR PROCESSING OR DEFINING LUMINANCE/COLOR REGIMES

摘要

To allow a better coordination between an image creation artist such as a movie director of photography and the final viewer, via a receiving-side display and its corresponding image processing, a method of adding display rendering specification information to an input image signal (I) comprises determining descriptive data (D) that includes at least identification information for at least one luminance regime subset of pixels of an input image; and encoding the descriptive data (D) into an output description data signal (DDO), relatable to an output image signal (O) based upon an input image signal (I), of the descriptive data (D) in a technical format standardized to be intended for use by a receiving-side display to control its image processing for changing the color properties of its rendered images.

主权项

1. A method of processing an input image signal (O) that comprises video images graded or defined in accordance with a maximum luminance value being a coding peak brightness (PB_C) of an image encoding that corresponds with an uppermost luminance of a luminance dynamic range (DR), which video images are encoded in a video transmission encoding suitable for communicating video to a video rendering-side, the video images for being processed to be rendered on one of various rendering-side video displays having different output luminance dynamic ranges defined by the uppermost luminance being a display-dependent display peak brightness (PB_D), and the processing being based on descriptive data (D) of an output description data signal (DDO) related to the video images, said method comprising:
extracting from an encoding of the output description data signal (DDO), the descriptive data (D) for use in specifying at least one luminance regime, wherein the descriptive data (D) comprises at least identification information for at least one subset of pixels of an input video image, wherein the identification information includes at least one luminance value (L_x) demarcating pixels having luminance respectively above or below the at least one luminance value (L_x); and color processing the input image signal (O), for a particular rendering-side video display having a display peak brightness (PB_D) of the various rendering-side video displays having different output luminance dynamic ranges, to obtain an output image (IR′) to be rendered based upon a color transformation processing determined from at least (i) the display peak brightness (PB_D) of the particular rendering-side video display, and (ii) a formulation of luminance rendering as a function of at least the identification information.