IVI LLC EXHIBIT 2013
`XILINX V. IVI LLC
`IPR Case 2013-00029
`
`

`

`US 6,985,253 B2
`
`Page 2
`
`Kennel and Snider, “Gray-Scale Transformations of Digital
`Film Data for Display, Conversion, and Film Recording” in
`the SMPTE Journal, vol. 102, Dec. 1993, pp. 1109-1119.
`EASTMAN Professional Motion Picture Films, Kodak
`Publication No. H-1 (CAT 155 2280, 12-92-E Major Revi-
`sion, Library of Congress Catalog Card No. 91-77432, ISBN
`0-87985-477-4), pp. 80-90.
`The Theory of the Photographic Process, Forth Edition, pp.
`517-535.
`
`Roberts and Eng, “Television Colorimetry: A tutorial for
`system designers”, Research and Development Report,
`1995, pp. 1-14.
`Markandey, Clatanoff and Pettitt, “Video Processing for
`DLP Display Systems”, SPIE Proceedings—vol. 2666, pp.
`21-32.
`
`US. PATENT DOCUMENTS
`
`Neyman
`................ 348/96
`Milson et al.
`
`Neyman .............
`386/42
`......... 382/167
`Giorgianni et al.
`Zolliker et al.
`............... 355/32
`Redding et al.
`347/43
`Shimizu ..........
`.. 382/162
`
`........... 348/234
`Easwar et al.
`
`...... 348/222.1
`Guimaraes et al.
`Rudolph ..................... 347/100
`Sowinski et al.
`Shiota et al.
`Bogdanowicz et 211.
`Jones et 211.
`
`6/1999
`9/2000
`9/2001
`7/2002
`12/2002
`6/2004
`6/2004
`1 1/2004
`3/2005
`5/2005
`12/2001
`5/2002
`1 1/2002
`1 1/2002
`
`AA
`
`*
`B1*
`B1*
`B1*
`B2*
`B2*
`B1*
`B1*
`B2*
`A1*
`A1*
`A1*
`A1*
`
`5,917,987
`6,115,062
`6,292,617
`6,424,740
`6,498,638
`6,742,869
`6,751,346
`6,825,876
`6,864,915
`6,886,932
`2001/0053247
`2002/0057460
`2002/0163657
`2002/0163676
`
`OTHER PUBLICATIONS
`
`Giorgianni and Madden, Digital Color Mamigmeht Encod-
`ing Solutions, pp. 448-488.
`
`* cited by examiner
`
`

`

`US. Patent
`
`Jan. 10,2006
`
`Sheet 1 0f3
`
`US 6,985,253 B2
`
`FILM
`SCANNER
`
`12
`
`14
`
`16
`
`MOTION PICTURE V 20
`FILM RECORDER
`
`
`
`FIG.1
`
`26
`
`28
`
`
`
`22 f
`
`‘ G
`
`30
`
`
`
`
`OPTICAL
`
`
`PRIIITER
`
`POINTS
`PRINTER
`
` 27
`W
`
`w
`
`36
`
`MULTIPLIER
`
`PRINTING EXPOSURE
`DIFFERENCE
`
`37
`
`DIGITAL CODE VALUE
`DIFFERENCE
`
`34
`
`42
`
`40
`
`
`
`MOTION PICTURE
`FILM RECORDER
`
`45
`PRINTER
`
`
`
`PRINTER
`POINTS
`
`
`
` PRINT FILM
`
`M48
`
`
`
`35
`
`38
`
`LUT I'M 50
`
`MATRIX
`
`52
`
`54
`
`DEVICE INDEPENDENT
`CODE VALUE
`COMPUTATIONS
`
`56
`
`58
`
`

`

`US. Patent
`
`Jan. 10, 2006
`
`SheetZ 0f3
`
`US 6,985,253 132
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`US. Patent
`
`Jan. 10, 2006
`
`Sheet 3 0f 3
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`US 6,985,253 132
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`RELATIVE LUMINANCE
`
`

`

`US 6,985,253 B2
`
`1
`PROCESSING FILM IMAGES FOR DIGITAL
`CINEMA
`
`FIELD OF THE INVENTION
`
`The present invention relates to the field of digital image
`processing. More specifically, it relates to the digital tone
`scale and color processing of negative or positive film
`images that have been digitized. This tone scale and color
`processing is optimized such that the digital images, when
`projected on a digital projector, match the colorimetry or
`appearance that a film projector would produce when pro-
`jecting the motion picture print from the originating film.
`
`BACKGROUND OF THE INVENTION
`
`With the arrival of digital cinema, the necessity grows to
`achieve a high quality imaging system for consumers. The
`public has become accustomed to the traditional “film look”
`that they see when going to the movie theater. With digital
`cinema, digital projectors need to produce an image on the
`screen that preserves that “film look” since it is a pleasing
`and widely accepted look. After obtaining a digital image by
`scanning a motion picture film, the process of transforming
`the digital data, so that it has the “film-look” when it is
`projected on a digital projector, is a very tedious, costly and
`time-consuming process carried out by professionals known
`as colorists.
`US. Pat. Nos. 5,809,164 and 5,239,370 disclose color
`management systems for emulating the “film-look” by
`focusing on gamut mapping or compression. Both patents
`assume that the capturing device has spectral sensitivities
`that are linear combinations of the CIE 2° Color Matching
`Functions. US. Pat. No. 4,839,721 states that the transfor-
`mation between the capture medium and the selected color
`space is performed with a substantially linearized response
`of the capture medium to the selected color space. It would
`be an advantage if the spectral sensitivities or response of the
`capturing device do not need to be a linear combination of
`the CIE 2° Color Matching Functions or of the selected color
`space.
`US. Pat. No. 5,687,011 discloses a system in which a
`video image and a film image are simultaneously captured,
`and a computer reassigns color component data based on
`digital data representative of color component data within
`the image recorded on film. This is an impractical approach
`because of the necessity of having to concurrently record a
`film and a video image. It would be an advantage if there
`were no need to capture the scene on video to be able to do
`the transformation of the digital data to match film projec-
`tion results.
`
`US. Pat. No. 5,909,291 discloses a color matching system
`that initializes a translator by storing profiles of source and
`destination color devices which include the coordinates in a
`
`calibrated color space of the colorants produced in the
`source and destination devices and a tonal reproduction
`curve for each device. It would be an advantage if it were not
`necessary to store any profiles from source or destination
`devices.
`
`time, professionals known as colorists
`At the present
`spend a great amount of time empirically varying the tone
`scale and color of digitized film images to match, on a digital
`projector, the look that a film projector would have produced
`for the same material. A robust, straightforward method is
`needed that transforms film-originated and scanned digital
`images for digital projection so that the projected images
`emulate film projected images while, at
`the same time,
`
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`eliminating the need for any manual adjustments to the color
`and tone scale of digitized images after the originating film
`has been adjusted for color and tone to create an acceptable
`release print.
`
`DISCLOSURE OF THE INVENTION
`
`It is an object of the present invention to provide digital
`image processing wherein the spectral sensitivities or
`response of the capturing device do not need to be a linear
`combination of the CIE 2° Color Matching Functions or of
`the selected color space.
`It is another object of the present invention to provide
`digital image processing wherein there is no need to capture
`the scene on video to be able to do the transformation of the
`
`digital data to match film projection results.
`It is another object of the present invention to provide
`digital image processing wherein it is unnecessary to store
`any profiles from source or destination devices.
`It is another object of the present invention to provide
`digital image processing that achieves a colorimetric match
`between image “A” and image “B”; wherein image “A” is
`a motion picture film image that is projected under motion
`picture viewing conditions using a motion picture print film
`projection system, and image “B” is a digital image that
`originated on motion picture film and was transformed to
`digital domain by scanning the motion picture film, and that
`is displayed under the same viewing conditions as image
`“A”, using a digital projector.
`It is another object of the present invention to provide
`digital image processing that achieves an appearance match
`between image “A” and image “C”; wherein image “C” is a
`digital image, that originated on motion picture film and was
`transformed to digital domain by scanning the motion pic-
`ture film, using a motion picture film scanner, and that is
`projected under different viewing conditions to those of
`image “A”, using a digital projector.
`It is another object of the present invention to provide a
`robust, straightforward method that transforms film origi-
`nated and scanned digital images for digital projection so
`that they emulate film projected images, while, at the same
`time, eliminating the need for any manual adjustments to the
`color and tone scale of digitized images after the originating
`film has been adjusted for color and tone to create an
`acceptable release print.
`It is another object of the present invention to implement
`a robust, straightforward approach to creating a colorimetric
`match between digital images projected on a digital projec-
`tor and film images projected on a film projector so that the
`digitally projected images emulate
`the
`film-projected
`images.
`It is another object of the present invention to provide a
`digital image processing method which can be easily modi-
`fied to obtain an appearance match between the film-
`projected image and the digitally projected image when
`viewing conditions are different.
`It is another object of the present invention to provide
`digital image processing which takes advantages of the color
`adjustments made when creating a print release film, thereby
`avoiding any further manual adjustments to the color or tone
`scale of the images after they have been digitized.
`According to a feature of the present invention, scanner
`density values of a digitized image of an original film are
`processed so that a projection of the digitized image closely
`matches that image which a film projector would produce
`when projecting the original film. A method comprises the
`steps of transforming the scanner density values to printing
`
`

`

`US 6,985,253 B2
`
`3
`density values; digital color balancing by writing the print-
`ing density values and a LAD patch onto film; printing the
`film according to the LAD procedure;
`transforming the
`images from device dependent color space values into
`device independent color space values; carrying out a rela-
`tionship between the device independent color space and a
`display device output to obtain RGB code values; adjusting
`any non-linearity between the RGB code values and the
`display device output; and scaling the adjusted RGB code
`values to an appropriate bit depth.
`The invention, and its objects and advantages, will
`become more apparent in the detailed description of the
`preferred embodiments presented below.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`In the detailed description of the preferred embodiments
`of the invention presented below, reference is made to the
`accompanying drawings, in which:
`FIG. 1 is a schematic block diagram of a process accord-
`ing to the present invention to go from digitizing the film to
`device independent color values;
`FIG. 2 is a schematic block diagram of the process
`according to the present invention to go from device inde-
`pendent color values to a digital projector’s RGB code
`values; and
`FIG. 3 shows one transfer function curve relationship for
`a digital projector.
`
`DETAILED DESCRIPTION OF THE
`INVENTION
`
`Referring to FIG. 1, film images and a Laboratory Aim
`Density (LAD) patch are digitized using a motion picture
`film scanner 12. Utilizing LAD patches is disclosed in
`SMPTE Journal Volume 85, Oct. 1976, in the article A
`Simplified Motion-Picture Laboratory Control Method for
`Improved Color Duplication, pages 781—785, by Pytlak and
`Fleischer. The resulting scanner density values 14 are trans-
`formed to printing density values 16 by a matrix 18. The
`matrix may be obtained by regression between scanner
`density values and corresponding printing density values, a
`well know mathematical procedure to those skilled in the art.
`The use of one-dimensional Look-Up Tables (LUTs) is also
`available for this transformation. The scanner density and
`printing density terms are defined in the text Digital Color
`Management, by Giorgianni and Madden, pages 448—457.
`After matrixing at 18, digital color balancing is carried
`out. Just as optical color balancing enhances color repro-
`duction and overall density for conventionally printed
`images, digital color balancing enhances color reproduction
`and overall density when digital data is written to film and
`subsequently printed. Digital color balancing is effected by
`writing the transformed film images and LAD patch onto
`film 22 using a motion picture film recorder 20. The proce-
`dure of digitally recording images that originate on film is
`documented in SMPTE Journal Volume 102, Dec. 1993, in
`the article Gray-Scale Transformations ofDigital Film Data
`for Display, Conversion, and Film Recording, by Kennel
`and Snider.
`
`Digitally recorded motion picture negative film 22 is
`conventionally printed at 26 onto motion picture print film
`27 according to the LAD procedure; thus creating a “LAD
`Print.” A discussion of printing of motion picture films is
`given in EASTMAN Professional Motion Picture Films,
`Kodak Publication H-1 (CAT 155 2280, 12-92-E Major
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`4
`Revision, Library of Congress Catalog Card No. 91-77432,
`ISBN 0-87985-477-4), pages 80—90.
`The red, green, and blue light values in an additive printer
`can be adjusted by values, called “printer points” (also
`referred to in the art as “printer lights” in the Pytlak and
`Fleischer article). The printer points are integers from one to
`fifty, and are fed into printer 26 from a source 28 by
`perforated paper tape, and are recorded on the film. Achange
`of one printer point is equivalent to a change to the print film
`of 0.025 logE. A description of printer points is given on
`pages 88—89 of publication H-1, supra. Therefore, the opera-
`tor of the printer always knows or can read from the paper
`tape the printer points used during the printing of any film.
`Digitally recorded motion picture negative film 22 is also
`printed onto motion picture print film 30 to obtain a “Best
`Print.” Experienced printing technicians (color-timers) carry
`out this step. Again, the printer points are recorded.
`A Printing Exposure Difference value is determined at 32
`from the printer points. The Printing Exposure Difference
`value is equal to 0.025 times the difference between the
`Printer Points recorded on LAD Print 27 and the Printer
`
`Points recorded on Best Print 30. At 34, the Printing Expo-
`sure Difference value is multiplied by 12.5 to give a Digital
`Code Value Difference 35.
`
`A multiplier 36 determines a Film Image Code value 37
`as the product of 500 times Printing Density values 16. At
`an Adder 38, Digital Color Balanced Code Values 39 are
`calculated by adding Digital Code Value Difference 35 to the
`Film Image Code values 37. This allows the images to be
`printed according to the LAD procedure and at the same
`time to be the best prints. Coming off Adder 38, Digital
`Color Balanced Code values are inputted to a Motion Picture
`Film Recorder 40 that is identical to Motion Picture Film
`
`Recorder 18. Recorder 40 writes the digital images and LAD
`patch onto a film 42. Film 42 is printed, using a conventional
`printer 44 with printer points from a source 46, to make a
`film print 48. This printing operation can be done using the
`LAD procedure. Because of the steps from 18 through 38,
`print 48 is also the best print. Although the steps 18 through
`48 may seem like overly complex steps, they are relatively
`easy to perform, the “rules” to perform them are well known
`in the motion picture industry, and the result is the best print
`in a straightforward way. In film labs that print motion
`picture film,
`the LAD procedure is well-established.
`In
`addition, the Digital Color Balanced Code Values out of
`Adder 38 from different scenes of a movie can be digitally
`intercut with confidence that when the resulting movie is
`shown (whether by following steps 40 through 48 or by
`following a digital projection route following step 48 ) all of
`the scenes will be optimum for color and density.
`The Digital Color Balanced Code Values from Adder 38
`are also transformed to a set of analytical density values by
`a set of three one-dimensional LUTs 50. These LUTs are
`determined from the characteristic curve, also known as the
`D-logE curve, of the print film material. The characteristic
`curve can be plotted as measured density on the y-axis and
`Code Value on the x-axis, where
`Code Value=500*Printing Density.
`
`The characteristic curve is normally measured as an
`integral density curve, for example, a “Status A Density”
`curve. Status Adensity is also known as integral density, and
`is a measure of the light absorbing power of a material. In
`film, the individual components absorbing the light are the
`base, the gelatin, the cyan dye, the magenta dye, the yellow
`dye, and any other absorbing materials in the film. The base,
`the gelatin, and the other absorbing materials usually absorb
`
`

`

`US 6,985,253 B2
`
`5
`a constant fraction of the light independent of the amount of
`cyan, magenta, or yellow dyes. The cyan dye absorbs
`primarily red light, but also absorbs some green and some
`blue light. The magcnta dyc absorbs primarily green light,
`but also absorbs some red and blue light. The yellow dye
`absorbs primarily blue light, but also absorbs some red and
`green light. In order to calculate the color of any patch, it is
`important to know the amount of each dye in the patch.
`Analytical densities are proportional to the amounts of the
`dyes, not to the absorbing properties of the dyes. Therefore,
`a characteristic curve that shows the relationship between
`the analytical densities (y-axis) and the code values (x-axis)
`is more useful than a characteristic curve that shows the
`
`Status A densities (y-axis) and the code values (x-axis). For
`a description of printing density, integral density, analytical
`density, and conversions among them, see The Theory of The
`Photographic Process, by T. H. James, pages 517—535).
`The necessity for inter-image effects corrections will
`depend on how the motion picture print film behaves. In
`order to know if it is necessary to make a correction for
`inter-image effects, it is necessary to measure the print film.
`An experiment to run is described in the James book on page
`534. Briefly, the film is exposed through a step tablet with
`one color light (red, green, or blue light). Next, the film is
`given a uniform exposure with the other two light colors.
`The film is processed, and the Status A densities are mea-
`sured. The Status A densities are converted to analytical
`densities, and the analytical densities are plotted against the
`code values as explained above. The analytical densities
`corresponding to the dye associated with the light exposure
`through the step tablet will show variation from a low value
`to a high value. If there are no inter-image effects in the film,
`the other two analytical densities will be constant, and they
`will not have changed with the changes in the other dye. If
`there are inter-image effects in the film,
`the other two
`analytical densities will either increase or decrease, and they
`will have changed with the changes in the other dye. If
`necessary, a correction for inter-image effects is applied by
`a matrix 52 to produce inter-image effects corrected Ana-
`lytical Dcnsity values 54. The result of that matrix multi-
`plication is a mathematical modeling of the chemical inter-
`image effects in the film. If there are no inter-image eifects,
`matrix 52 is a unity matrix, and the set of three one-
`dimensional LUTs 50 and matrix 52 can be combined into
`
`a set of three one-dimensional LUTs creating a direct
`relationship between printing density and analytical densi-
`ties formed on the motion picture print film.
`Dye set curves describe the spectral density curves of the
`imaging dyes in the film. Normalized dye set curves describe
`the spectral density curves of the imaging dyes in the film for
`a neutral reference. The spectral curve DO») for any color
`patch can be calculated from the equation:
`
`D()\.)=C *C(}»)+m *M(}t)+y*Y(}t)+Dmin(}t)
`
`where, CO»), MO»), and Y0») are respectively the spectral
`density distributions of the cyan, magenta, and yellow dyes
`as a function of wavelength A; and c, m, and y are respec-
`tively the analytical density values of the cyan, magenta, and
`yellow dyes.
`Thus, the c, m, and y analytical density values are used to
`modulate at 56 appropriately normalized print film dye set
`curves. Modulating these curves according to the analytical
`densities produces the spectrum, in density space, of the
`image formed in the motion picture print film. The density
`spectrum is then transformed to linear (transmittance) space
`
`6
`to compute the device independent color values 58. The
`equation to go from density to transmittance is:
`
`T(>t)—10.0<*D(A))
`
`This is all effected in software, but could be implemented in
`hardware.
`
`It is possible to specify a color on a color monitor by
`specifying the drive values (code values) for the primaries 0f
`the monitor. However, these numbers depend on what the
`primaries are. If a person uses a different monitor with
`different primaries, a different set of code values are needed.
`An objective of the present invention is to express the color
`patch in device independent color values 58. That is, the
`color of the patch is specified by a set of numerical values
`that are independent of the device producing the colors. CIE
`XYZ (tristimulus) values are one such set of numbers. There
`are other numbers that could be used, for example CIELab
`coordinates, CIELuv coordinates, CIE x, y, Y coordinates,
`CIE u', v', Y coordinates, etc. The tristimulus values are
`defined as follows:
`
`hivisual
`X 2k 2 Illum(/\)-0ptics(A)-X(/l)-Trans(/l)
`
`hivisual
`Y = k 2 Ilium(A)-0ptics(A)-y(A)-Trans(/l)
`
`hivisual
`Z: k 2 1111411101)-0ptics(/l)-Z(A)-Trans(/l)
`
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`where:
`
`IllumO») is the light source power spectrum,
`OpticsO») represents the net spectra of any optical ele-
`ments in the viewing path between the light source and
`the human eye,
`
`J—C(}\.);O\.)20\.) are the CIE 2° standard observer Color
`Matching Functions,
`TransO»)
`is the transmittance spectrum of the object
`imaged in the motion picture print film, and
`k is a normalizing constant that makes Y equal to 100 for
`a 100% white reference.
`
`If a piece of white paper is viewed in one illuminant, say
`D50, it will appear white. If the same piece of white paper
`is viewed in another illuminant, say D65, it will again appear
`white. The eyes adapt to the illuminant such that a white
`appears white under most illuminants. Yet the XYZ tris-
`timulus values will be different for the same piece of white
`paper in the two different illuminants. Although the XYZ
`values give a unique definition of color, this is only true
`relative to the illuminant. One therefore needs to modify the
`XYZ values for any shift
`in illuminants. Once device
`independent color space values 58 are obtained, any type of
`chromatic adaptation function can be applied to them. One
`example of this would be a VonKries chromatic adaptation,
`which is also documented in the text Digital Color Man-
`agement, by Giorgianni and Madden, pages 479—481. The
`VonKries adaptation method is well known and works well
`for the types of illuminant changes one might encounter in
`a motion picture environment. There are other adaptation
`equations. The form of a VonKries adaptation equation is:
`
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`US 6,985,253 B2
`
`X’
`Y’
`Z’
`
`= [M]-
`
`X
`Y
`
`Z
`
`
`
`where X', Y' and Z' are the chromatically adapted tristimulus
`values and M is the chromatic adaptation matrix. Giorgianni
`and Madden goes through an example of how to calculate
`M.
`
`In some implementations it will be reasonably fast to go
`through all of the calculations just described above for each
`pixel
`in the image. However, for other applications,
`to
`calculate each pixel by the above equations for each image
`will be too slow. Therefore, a faster implementation is
`needed. One faster alternative implementation can be a
`three-dimensional LUT (not shown). The three-dimensional
`LUT can be implemented in hardware and will provide very
`fast implementation of what we have described. The three-
`dimensional LUT values can be calculated using the above-
`described technique.
`Referring to FIG. 2, it is necessary to create a relationship
`between the device independent color space values 58 and
`RGB code values 60 for the display device, for example a
`digital projector. The relationship between device indepen-
`dent color space values and RGB code values for the display
`device can be characterized by a matrixing operation 62. For
`an example of such a procedure see the report by the BBC
`Research and Development titled Television Calorimetry: A
`Tutorial for System Designers (BBC RD 1995/9), by Rob-
`erts. The following equation shows matrixing operation 62:
`
`
`
`
`
`
`
`
`
`where the XYZ vector represents the CIE XYZ tristimulus
`values associated with a set of RGB linear drive values, and
`M is matrix 62 used for the transformation.
`
`If the relationship between the light emitted by an
`intended display device 64 is linearly related to RGB code
`values 60, then the RGB code values computed by matrixing
`operation 62 are the values inputted to the digital display
`device, scaled up to the appropriate bit depth at 66. If the
`relationship between the light emitted by an intended display
`device 64 is non-linearly related to RGB code values 60,
`then the RGB code values computed by matrixing operation
`62 need to be adjusted by a transformation that characterizes
`the non-linear relationship before the code values are scaled
`up to the appropriate bit depth at 68. The transformation that
`characterizes the non-linear
`relationship can be imple-
`mented, as an example, with a one-dimensional LUT 70. It
`is important
`to mention that for a DLP (Digital Light
`Processing) digital projector,
`the inherent
`relationship
`between RGB code values 60 and light output is linear, but
`the hardware provides for a non-linear setting. This is to
`compensate for previously corrected video signals that were
`tailored for phosphor based display devices, which have an
`inherent non-linear relationship between RGB code values
`and light output. This is documented in the SPIE Proceed-
`ings Vol. 2666 paper, Video Processing for DLP Display
`Systems, by Markandey, Clatanoff and Pettitt of Texas
`Instruments, Inc.
`
`8
`Any type of dark surround adaptation or flare corrections
`can be applied to the RGB code values 60 for display device
`64 if the illumination levels or dark surround conditions
`
`where the display device is located do not match those
`conditions where traditional motion picture print film is
`viewed. These corrections are also documented in the text
`
`Digital Color Management, by Giorgianni and Madden,
`pages 474—478 and 484—488. FIG. 3 shows, as an example,
`one transfer function curve relationship for the digital pro-
`jector.
`Finally, the processed images are projected under motion
`picture viewing conditions, according to the Society of
`Motion Picture and Television Engineers (SMPTE) stan-
`dards, sending the data to the display device in full RGB
`resolution.
`
`The invention has been described in detail with particular
`reference to preferred embodiments thereof, but it will be
`understood that variations and modifications can be effected
`
`within the spirit and scope of the invention.
`
`What is claimed is:
`
`1. A method of processing scanner density values of a
`digitized image of an original film image such that a
`projection of the digitized image closely matches an image
`which a film projector would produce using a positive print
`of the original film image; said method comprising the steps
`of:
`
`transforming the scanner density values to printing den-
`sity values;
`digital color balancing by writing the printing density
`values and a reference patch onto a first film;
`printing the first film with the reference patch onto a
`second film according to a predetermined printing
`procedure;
`transforming the digitized images from device dependent
`color space values into device independent color space
`values;
`carrying out a relationship between the device indepen-
`dent color space values and a display device output to
`obtain RGB code values;
`adjusting any non-linearity between the RGB code values
`and the display device output; and
`scaling the adjusted RGB code values to a desired bit
`depth.
`2. Amethod as set forth in claim 1, further comprising the
`step of obtaining the scanner density values by using a
`motion picture film scanner.
`3. A method as set forth in claim 1, wherein the device
`independent color space values are CIE XYZ color space
`values.
`
`4. A method as set forth in claim 1, wherein the device
`dependent color space values are printing density values.
`5. A method as set forth in claim 1, wherein the transfor-
`mation into the device independent color space values is
`implemented by a series of one-dimensional LUTs (Look-
`Up Tables) and matrices.
`6. A method as set forth in claim 1, wherein the transfor-
`mation into the device independent color space values is
`implemented by a three-dimensional LUT.
`7. A method as set forth in claim 1, wherein the transfor-
`mation into the device independent color space values
`describes a linear relationship between the device dependent
`color space values and the device independent color space
`values.
`
`8. A method as set forth in claim 1, wherein the transfor-
`mation into the device independent color space values
`
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`

`

`US 6,985,253 B2
`
`9
`relationship between the device
`describes a non-linear
`dependent color space values and the device independent
`color space.
`9. Amethod as set forth in claim 1, further comprising the
`step of applying a chromatic adaptation function to the
`device independent color space values.
`10. A method as set forth in claim 9, wherein the chro-
`matic adaptation function applied to the device independent
`color space values is a VonKries chromatic adaptation.
`11. A method as set forth in claim 1, wherein the step of
`carrying out a relationship between the device independent
`color space values and a display device output is effected by
`a matrix transformation between the device independent
`color values and the RGB code values for the display device.
`12. A method as set forth in claim 1, further comprising
`the step of applying dark surround adaptation to the RGB
`code values to accommodate illumination levels and dark
`
`surroundings that do not match those conditions where
`traditional motion picture print film is viewed.
`13. A method as set forth in claim 1, further comprising
`the step of applying flare corrections to the RGB code values
`to accommodate illumination levels and dark surroundings
`that do not match those conditions where traditional motion
`
`picture print film is viewed.
`14. Amethod as set forth in claim 1, wherein the reference
`patch is an LAD patch.
`15. A method as set forth in claim 1, wherein the prede-
`termined printing procedure is an LAD procedure.
`16. A method of processing received density values of a
`digitized image such that a projection of the digitized image
`closely matches an image which a film projector would
`produce using a positive print of an original film image; said
`method comprising the steps of:
`transforming the received density values to printing den-
`sity values;
`digital color balancing by writing the printing density
`values and a reference patch onto a first film;
`printing the first film with the reference patch onto a
`second film according to a predetermined printing
`procedure;
`transforming the digitized image from device dependent
`color space values into device independent color space
`values;
`carrying out a relationship between the device indepen-
`dent color space values and a display device output to
`obtain RGB code values;
`adjusting any non-linearity between the RGB code values
`and the display device output; and
`scaling the adjusted RGB code values to an appropriate
`bit depth.
`
`10
`17. A method as set forth in claim 16, wherein the device
`independent color space values are CIE XYZ color space
`values.
`
`18. A method as set forth in claim 16, wherein the device
`dependent color space values are printing density onto
`motion picture print film.
`19. A method as set forth in claim 16, wherein the
`transformation into the device independent color space
`values is implemented by a series of one-dimensional LUTs
`(Look-Up Tables) and matrices.
`20. A method as set forth in claim 16, wherein the
`transformation into the device independent color space
`values is implemented by a three-dimensional LUT.
`21. A method as set forth in claim 16, wherein the
`transformation into the device independent color space
`values describes a linear relationship between the device
`dependent color space values and the device independent
`color space values.
`22. A method as set forth in claim 16, wherein the
`transformation into the device independent color space
`values describes a non-linear
`relationship between the
`device dependent color space values and the device inde-
`pendent color space values.
`23. A method as set forth in claim 16, further comprising
`the step of applying a chromati