Method of digital processing for digital cinema projection of tone scale and color

Abstract

A method for re-mapping out of gamut colors into a display device color space. The method includes determining a maximum color gamut of the display device in a perceptual color space that represents the combination of hue, lightness and saturation; and determining if a target color is out of gamut for the display device. Accordingly, an out of gamut target color is provided. One may then obtain a hue angle for the out of gamut target color. Using the hue angle, one determines the lightness value of the out of gamut target color. Subsequently, one would hold the one holding the hue angle constant, altering the lightness and saturation, as necessary to bring the out of gamut target color into the display device color space.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This is a Divisional application of U.S. Ser. No. 09 / 797,891; filed Mar. 2, 2001; of Mitchell J. Bogdanowicz, Carlo V. Hume and Charles P. Hagmaier, entitled “Method Of Digital Processing For Digital Cinema Projection Of Tone Scale And Color”.FIELD OF THE INVENTION [0002] The present invention relates generally to the field of video processing or digital image processing to emulate motion picture film tonescale and color. More specifically, the invention relates to rendering an electronic image to emulate a film system reproduction, that is, to provide the appearance of an image captured and displayed with motion picture film. BACKGROUND OF THE INVENTION [0003] The digital era that is now upon us has the potential to change the way everyone operates in the motion picture field. The traditional method for projecting motion picture film was relatively simple because there were not very many options available to be controlled. Basically, f...

AI Technical Summary

Benefits of technology

[0015] This invention is a straightforward, reliable, and practical process for converting digital image sequences so that their appearance matches that of projected motion picture print film. In addition, the technique can be used to assist capturing of image sequences.

[0016] This invention provides a standard process for digital cinema presentation. The process can be employed not only at projection, but also at capture. Current industry methods are time consuming, inconsistent, and unpredictable. Colorists spend countless hours each year to adjust image sequences in order to match a desired output response. This invention provides a fast and reliable process for matching a digital source to a motion picture print film release. It therefore greatly minimizes the work involved by a colorist to adjust the flesh tone and co

Problems solved by technology

The traditional method for projecting motion picture film was relatively simple because there were not very many options available to be controlled.

However, the more variables one has to work with, the harder it is to maintain or reconstruct the original intent.

However, the prior art neglects the emulation of the look of film origination, as if a negative film has been directly printed and projected through a motion picture system.

This is an imperfect alteration because it cannot operate upon the scene exposure as seen by a film.

Images