Projection system and method using mixed color gamut

Abstract

The projection system and method therefore involve a first projection device; a second projection device; at least one spatial modulator; and an electronic processor configured to: receive two-dimensional video data, generate a first plurality of intensity values ​​of a first color gamut and a second plurality of intensity values ​​of a second color gamut, subtract a brightness threshold from a plurality of pixel values ​​of the second color gamut to produce a plurality of positive pixel values ​​and a plurality of negative pixel values, set corresponding pixel values ​​of the plurality of pixel values ​​to predetermined values ​​to obtain a residual of the second color gamut, add the residual to the first color gamut, add the maximized pixel value to the first color gamut and the second color gamut to create an output color gamut, and mix the output color gamut with the native color gamut to generate a mixed color gamut.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Provisional Patent Application No. 62 / 967,821 filed on January 30, 2020 and U.S. Provisional Patent Application No. 63 / 125,160 filed on December 14, 2020, which are incorporated herein by reference. Technical Field

[0003] The present application relates generally to systems and methods for rendering and projecting images. Background Art

[0004] Displays capable of displaying three-dimensional (3D) images may use two different sets of primary colors ("six primaries" or 6P) to display left-eye and right-eye images that give the appearance of a 3D image when viewed together. Such displays may also be used to display two-dimensional (2D) images. Summary of the invention

[0005] Various aspects of the present disclosure relate to devices, systems, and methods for rendering wide color gamut images.

[0006] In an exemplary aspect of the present disclosure, a projection system is provided, comprising a first projection device, a second projection device, at least one spatial modulator, and an electronic processor, the electronic processor being configured to: receive two-dimensional video data; generate a first plurality of intensity values ​​of a virtual primary color of a first color gamut and a second plurality of intensity values ​​of a virtual primary color of a second color gamut from the video data; subtract a brightness threshold from a plurality of pixel values ​​of the second color gamut to generate a plurality of positive pixel values ​​and a plurality of negative pixel values; set corresponding pixel values ​​among the plurality of negative pixel values ​​of the second color gamut to a predetermined value to obtain a residual of the second color gamut; add the residual of the second color gamut to the first color gamut; add the maximized pixel value to the first color gamut and the second color gamut within the two-dimensional video data to create an output color gamut; mix the output color gamut with a native color gamut of the projection system to generate a mixed color gamut; and drive the first projection device and the second projection device based on the mixed color gamut.

[0007] In another exemplary aspect of the present disclosure, a method for rendering a wide color gamut image using a projection system is provided, the projection system comprising a first projection device, a second projection device and at least one spatial modulator, the method comprising: receiving two-dimensional video data; generating a first plurality of intensity values ​​of a virtual primary color of a first color gamut and a second plurality of intensity values ​​of a virtual primary color of a second color gamut from the video data; subtracting a brightness threshold from a plurality of pixel values ​​of the second color gamut to produce a plurality of positive pixel values ​​and a plurality of negative pixel values; setting corresponding pixel values ​​among the plurality of negative pixel values ​​of the second color gamut to a predetermined value to obtain a residual of the second color gamut; adding the residual of the second color gamut to the first color gamut; adding a maximized pixel value to the first color gamut and the second color gamut within the two-dimensional video data to create an output color gamut; mixing the output color gamut with a native color gamut of the projection system to generate a mixed color gamut; and driving the first projection device and the second projection device based on the mixed color gamut.

[0008] In another exemplary aspect of the present disclosure, a non-transitory computer-readable medium storing instructions is provided, which, when executed by a processor of a projection system including a first projection device, a second projection device and at least one spatial modulator, causes the projection system to perform operations, the operations including receiving two-dimensional video data; generating a first plurality of intensity values ​​of a virtual primary color of a first color gamut and a second plurality of intensity values ​​of a virtual primary color of a second color gamut from the video data; subtracting a brightness threshold from a plurality of pixel values ​​of the second color gamut to produce a plurality of positive pixel values ​​and a plurality of negative pixel values; setting corresponding pixel values ​​among the plurality of negative pixel values ​​of the second color gamut to predetermined values ​​to obtain a residual of the second color gamut; adding the residual of the second color gamut to the first color gamut; adding the maximized pixel value to the first color gamut and the second color gamut within the two-dimensional video data to create an output color gamut; mixing the output color gamut with the native color gamut of the projection system to generate a mixed color gamut; and driving the first projection device and the second projection device based on the mixed color gamut.

[0009] In this way, various aspects of the present disclosure provide for the display of images with high dynamic range, high resolution, and wide color gamut, and achieve improvements in at least the technical fields of image projection, holography, signal processing, and the like. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The accompanying drawings, together with the following detailed description, are incorporated in and form a part of the specification to further illustrate the embodiments of the concepts and to explain the various principles and advantages of those embodiments. In the accompanying drawings, like reference numerals refer to the same or functionally similar elements in each view.

[0011] Those skilled in the art will appreciate that the elements in the drawings are shown for simplicity and clarity and are not necessarily drawn to scale. For example, the size of some elements in the drawings may be exaggerated relative to other elements to help improve the understanding of the embodiments of the present disclosure.

[0012] In the drawings, apparatus and method components are symbolized where appropriate, and only those specific details relevant to understanding the embodiments of the present disclosure are shown so as not to obscure the present disclosure with details that would be readily apparent to one of ordinary skill in the art having the benefit of the description herein.

[0013] Figure 1A is a spectrum diagram of an exemplary 6P projection system according to various aspects of the present disclosure.

[0014] Figure 1B is a block diagram of an exemplary projection system according to various aspects of the present disclosure.

[0015] Figure 1C is a block diagram of an exemplary projection system according to various aspects of the present disclosure.

[0016] Figure 2 According to various aspects of the present disclosure, Figure 1B and 1C Block diagram of an exemplary controller in a system.

[0017] Figure 3 It is shown that according to various aspects of the present disclosure Figure 2 A flowchart of an exemplary method implemented by a controller.

[0018] Figure 4 is an exemplary chromaticity diagram according to various aspects of the present disclosure.

[0019] Figure 5A is an exemplary chromaticity diagram according to various aspects of the present disclosure.

[0020] Figure 5B is an exemplary chromaticity diagram according to various aspects of the present disclosure.

[0021] Fig. 6A is an exemplary chromaticity diagram according to various aspects of the present disclosure.

[0022] Figure 6B is an exemplary chromaticity diagram according to various aspects of the present disclosure.

[0023] Fig. 7A is an exemplary chromaticity diagram according to various aspects of the present disclosure.

[0024] Figure 7B is an exemplary chromaticity diagram according to various aspects of the present disclosure.

[0025] Fig. 8A is an exemplary chromaticity diagram according to various aspects of the present disclosure.

[0026] Figure 8B is an exemplary chromaticity diagram according to various aspects of the present disclosure. DETAILED DESCRIPTION

[0027] As described above, some 6P displays configured to project 3D images can be used to project / display 2D images. When projecting 3D images, six primary colors are used to display left and right eye images, where a set of three primary colors (red, green, and blue) are used for left eye images and another set of three primary colors are used for right eye images. The 3D glasses used with such displays can have corresponding filters (e.g., bandpass filters) to allow each eye to see the appropriate image. By driving each pair of primary color light sources with the same data, a two-dimensional image can be displayed by a 3D display without requiring the viewer to wear 3D glasses. For example, a 2D red data value is used to drive both red 1 and red 2 primary colors. Similarly, a 2D green data value is used to drive both green 1 and green 2 primary colors, and a 2D blue data value is used to drive both blue 1 and blue 2 primary colors. The system is calibrated with the combined primary colors, and an image can be generated. However, the resulting color gamut may be significantly limited relative to a desired color gamut (e.g., the established Recommendation ITU-R BT.2020 (08 / 2012) parameter values ​​for ultra-high definition television systems for production and international program exchange, hereinafter referred to as the Rec2020 color gamut). Increasing the color gamut of the resulting 3D color volume may result in a reduced incidence of chroma errors (e.g., chroma clipping) and preservation of hue when clipping pixels that do not fit into the 3D color volume.

[0028] The present disclosure and its aspects may be embodied in various forms, including hardware or circuits controlled by computer-implemented methods, computer program products, computer systems and networks, user interfaces and application programming interfaces; as well as hardware-implemented methods, signal processing circuits, memory arrays, application specific integrated circuits, field programmable gate arrays, etc. The foregoing summary is intended only to give a general idea of ​​the various aspects of the present disclosure and is not intended to limit the scope of the present disclosure in any way.

[0029] In the following description, many details are described, such as circuit configuration, waveform timing, circuit operation, etc., in order to provide an understanding of one or more aspects of the present disclosure. It is obvious to those skilled in the art that these specific details are merely exemplary and are not intended to limit the scope of the present application.

[0030] In addition, although the present disclosure focuses primarily on the example that the received video data is Rec2020, it will be understood that this is only one example of implementation and other color spaces can be utilized. It should also be understood that the disclosed systems and methods can be used in any projection system to improve the rendering of 2D images on a six-primary color display.

[0031] Projector System

[0032] For ease of description, some or all of the example systems presented herein are illustrated by a single sample of each of their components. Some examples may not describe or illustrate all of the components of the system. Other example embodiments may include more or less of each of the illustrated components, may combine some components, or may include additional or alternative components. For example, in some embodiments, the following Figure 1B and 1C The system 100 includes more than one light source 102 .

[0033] As described above, some 3D displays referred to as a 6P system use two different sets of primary colors to simultaneously display a left-eye image and a right-eye image. Figure 1A Spectral diagram 1 of a 6P system according to some embodiments. Spectral diagram 1 includes three short wavelengths 2A, 3A and 4A (referred to as short primaries here), and three long wavelengths 2B, 3B and 4B (referred to as long primaries here). The example display system described here is configured to use short primaries 2A, 3A and 4A for left-eye images (e.g., by a designated left projector), and long primaries 2B, 3B and 4B for right-eye images (e.g., by a designated right projector). However, in other implementations, short primaries 2A, 3A and 4A may be used for right-eye images, and long primaries 2B, 3B and 4B may be used for left-eye images. Short primaries 2A, 3A and 4A may be, for example, a first blue wavelength, a first green wavelength and a red-blue wavelength, respectively. Long primaries 2B, 3B and 4B may be, for example, a second blue wavelength, a second green wavelength and a second red wavelength, respectively. The first red wavelength is shorter than the second red wavelength, the first green wavelength is shorter than the second green wavelength, and the first blue wavelength is shorter than the second blue wavelength. It should be understood that in further embodiments, a combination of short and long primaries may be used for each eye image. As explained in more detail below, each projector outputs a modulated light output (of the projector's designated primary color) to a display or viewing screen. In the embodiments described herein, the left eye image and the right eye image are displayed simultaneously.

[0034] Figure 1B and 1C 1 are block diagrams of exemplary display systems 100 according to some embodiments. Each system includes at least some similarly configured components, which are also labeled as such. Display system 100 is configured to display 3D and 2D video data received from a video data source 101. Display system 100 can be any kind of system configured to display images, such as a projection system or a light emitting diode (LED) display system. Display system 100 includes a light source 102, an illumination optical device 104, a separator 106, one or more modulators 108, a combiner 110, a projection optical device 112, and a controller 114. Although Figure 1B and 1COne light source 102 is shown, but the display system 100 according to some embodiments may include multiple light sources 102. The components of the system 100 may be housed in a single projection device (e.g., a single projector), or in some embodiments, may be housed in multiple devices. For example, in some embodiments, the light source, modulator, and other components of the display system 100 may be separated into two or more separate, coordinated projection devices. In such embodiments, each separate, coordinated projection device may process a set of wavelengths. For example, a first separate, coordinated projection device may separate, modulate, and combine short primaries 2A, 3A, and 4A, while a second separate, coordinated projection device may separate, modulate, and combine long primaries 2B, 3B, and 4B.

[0035] The light source 102 is driven by a controller 114 to generate an illumination beam that includes six primary colors in the illustrated embodiment. The illumination beam is directed through the illumination optics 104 and into the separator 106. The color separator 106 separates the illumination beam into six primary color beams and directs each primary color beam to an associated one of the spatial light modulators (SLMs) 108. Each modulator 108 modulates the primary illumination beam based on input from the controller 114, as will be described in more detail below. The projection optics 112 focus the modulated beams to form an imaging beam 116. The imaging beam 116 is then projected to produce an image on, for example, a viewing surface (not shown). Figure 1B In an exemplary system of , left-eye images and right-eye images may be projected alternately (also referred to as "time division multiplexing").

[0036] In some embodiments, each primary color may be associated with a separate modulator 108. Alternatively, Figure 1B As shown, the number of modulators can be reduced, for example, by using a field sequential modulation scheme. In some embodiments, the modulators can include multiple modulators for each primary color, such as in a dual modulation projector. In some embodiments, each modulator 108 is associated with a set of primary colors. For example, as described above with respect to Figure 1A As stated, Figure 1C As shown, a 6P system may include a left projector and a right projector. Figure 1CA dual-head display system 100 is shown, which includes separate modulators 108A and 108B, projection optics 112A and 112B (e.g., a first projection device 112A and a second projection device 112B), and two resulting imaging beams 116A and 116B, each set of imaging beams being designated for a left eye channel and a right eye channel, respectively. The modulator 108A, projection optics 112A, and resulting imaging beams 116A can be considered as components of a left projector (projection head), while the modulator 108B, projection optics 112B, and resulting imaging beams 116B can be considered as components of a right projector (projection head). As described above, the light output from the two channels is shown simultaneously to produce a single resulting image on a display or screen. In addition, although Figure 1B and 1C The video data source 101 is shown as being separate from the display system 100, but in some embodiments, the video data source 101 may be internal to the display system 100 (e.g., in a memory associated with the display system 100). In some embodiments, the splitter 106, one or more modulators 108, and the combiner 110 may be replicated continuously, such that a second combination of the splitter 106, one or more modulators 108, and the combiner 110 is repeated prior to the projection optical system 112. Additionally, the methods described herein may be performed in a device that does not include the splitter 106 and the combiner 110. Thus, such a device may use multiple projectors to provide illumination beams to be combined on a screen.

[0037] Figure 2 is a block diagram of a controller 114 according to some embodiments. The controller 114 includes an electronic processor 205, a memory 210, and an input / output interface 215. The electronic processor 205 obtains and provides information (e.g., from the memory 210 and / or the input / output interface 215), and processes the information by executing one or more software instructions or modules, which can be stored in, for example, a random access memory ("RAM") area of ​​the memory 210, or a read-only memory ("ROM") of the memory 210, or another non-transitory computer-readable medium (not shown). The software may include firmware, one or more applications, program data, filters, rules, one or more program modules, and other executable instructions. The electronic processor 205 may include multiple cores or separate processing units. The electronic processor 205 is configured to retrieve and execute software related to the control processes and methods described herein from the memory 210, etc.

[0038] Memory 210 may include one or more non-transitory computer-readable media and include a program storage area and a data storage area. As described herein, the program storage area and the data storage area may include a combination of different types of memory. Memory 210 may take the form of any non-transitory computer-readable medium.

[0039] The input / output interface 215 is configured to receive input and provide system output. The input / output interface 215 obtains information and signals from devices inside and outside the display system 100 (e.g., light source 102, one or more modulators 108, and video data source 101), and provides information and signals to them (e.g., through one or more wired and / or wireless connections).

[0040] Image rendering method

[0041] Figure 3 is a flow chart illustrating an example method 300 of operating a projection system according to some embodiments. As an example, the method 300 is described as comprising Figure 1B and 1C The controller 114 shown in FIG. 1 is executed, in particular, by Figure 2 The electronic processor 205 shown in FIG.

[0042] At block 302, the electronic processor 205 receives a video data source (eg, Figure 1B and 1C The video data source 101 shown receives video data. The video data may include a series of tristimulus pixel values ​​from a video content stream or file. In some embodiments, the video data includes pixel values ​​in a color space (or color gamut) such as Rec2020 (also known as ITU-R Recommendation BT.2020). At block 304, the electronic processor 205 generates a first plurality of intensity values ​​of virtual primary colors of a first color gamut from the video data, and at block 306, generates a second plurality of intensity values ​​of virtual primary colors of a second color gamut from the video data. In particular, the color gamut volume of the 2D image is divided into two virtual color gamuts: color gamut A and color gamut B. Each color gamut includes virtual primary colors that are a specific mixture of predefined primary colors. As explained in more detail below, color gamut A is selected to be as close as possible to a predefined color gamut, such as a defined standard color space (e.g., Rec2020), while color gamut B is used for any residual energy from the predefined primary colors. In other words, when applicable, color gamut A is used for lower brightness levels, and color gamut B is added to achieve higher brightness levels. In some embodiments, color gamut A is optimized to achieve the largest possible color gamut.

[0043] Back to Figure 3At block 308, the electronic processor 205 converts the first plurality of intensity values ​​into a third plurality of intensity values ​​of predefined primary colors for a first eye channel (e.g., a channel of a first projection head), and converts the second plurality of intensity values ​​into a fourth plurality of intensity values ​​of predefined primary colors for a second eye channel (e.g., a channel of a second projection head). In some embodiments, the first eye channel and the second eye channel are separate channels of the same projection head or projection device.

[0044] In some embodiments, a blending function is applied to color gamut A and color gamut B to optimize each color gamut to approximate the color space of the video data (in this example, Rec2020). In other words, in these embodiments, the electronic processor 205 converts the first plurality of intensity values ​​and the second plurality of intensity values ​​into a third plurality of intensity values ​​of predefined primary colors of a first eye channel (e.g., a channel of a first projection head), for example, through one or more blending functions. The electronic processor 205 also converts the first plurality of intensity values ​​and the second plurality of intensity values ​​into a fourth plurality of intensity values ​​of predefined primary colors of a second eye channel (e.g., a channel of a second projection head), for example, through one or more blending functions. The following equations [1] and [2] show the blending functions performed at block 308 for the left eye channel and the right eye channel, respectively.

[0045]

[0046] as well as

[0047]

[0048] R L , G L , B L The vector corresponds to a third plurality of intensity values, such as the primary colors of the right eye channel, R S , G S , B S The vectors correspond to a fourth plurality of intensity values, for example, the primary colors of the left eye channel, where R refers to the red primary, G refers to the green primary, B refers to the blue primary, the subscript L refers to the "long" wavelength primary, and the subscript S refers to the "short" wavelength primary. In some embodiments, the right eye channel may include short wavelength primary colors, while the left eye channel includes long wavelength primary colors. In both equations, the color gamut A (including R) of each channel A G A B A matrix) and color gamut B (including R B G B B B The matrix of AL , B BL , B AS and B BSThe specific values ​​of the mixing matrix can be predetermined values ​​determined based on the positions of the primary colors and the predetermined color space. The specific values ​​may also depend on the projection / display system used (e.g., the type of projection head). An example method for determining each mixed matrix is ​​described in more detail below. In this example, the following mixing matrix values ​​are used.

[0049]

[0050]

[0051]

[0052]

[0053] Back to Figure 3 At block 310, the electronic processor 205 dynamically adjusts at least one spatial modulator (eg, Figure 1B and C. In embodiments where system 100 is a dual head projection system, the pixel level of the modulator of each projection head is adjusted.

[0054] As described above, color gamut A is optimized to be as close as possible to a predefined color gamut, such as a defined standard color space (e.g., Rec2020), while color gamut B is used for any residual energy from predefined primary colors. Two exemplary methods implemented by processor 205 to process received video data into color gamuts A and B are described below.

[0055] One method to optimize the color gamut A is to scale (e.g., compress) the chrominance of the video data to fit within the achievable color gamut volume of the light source 102, referred to herein as color gamut scaling. In the color gamut scaling method, two functions are defined:

[0056] f l (P) = if (P < 0.5), P, else 0.5

[0057] f u (P) = Pf l (P)

[0058] P∈R 2020 ,G 2020 ,B 2020

[0059] The variable P represents the pixel value of the received video data, which is assumed to be tri-stimulus Rec2020 data. Function f l (P) represents the lookup table of color gamut A, and function f u (P) represents the lookup table of color gamut B. In this example, function f l(P) defines a linear slope increasing from 0 to 0.5 and a flat line above 0.5, while the function fu(P) defines a flat line from 0 to 0.5 and a linear slope increasing from 0.5. The value 0.5 corresponds to the brightness threshold. In some embodiments, different brightness thresholds can be used.

[0060] For each pixel value of the received video data, the color gamut A and color gamut B are derived as follows:

[0061]

[0062]

[0063] In other words, for the input video data R 2020 , G 2020 and B 2020 For each primary channel of , pixel values ​​having a luminance level below 0.5 (corresponding to 50% of the total luminance range of system 100 and 100% of the luminance range of gamut A) are included in gamut A, while pixel values ​​above 0.5 (meaning they are outside the luminance range of gamut A) are assigned to gamut B. The derived gamut A and gamut B signals are then converted to the defined primaries as described above with respect to block 308 and equations [1] and [2].

[0064] Another method of processing the received video data into color gamut A is to limit the chrominance to fit into color gamuts A and B to fit into the achievable color gamut volume of the light source 102. First, define the transformation relationship from the color space of the source 102 to color gamut A and color gamut B respectively [C] A and [C] B . This derivation can be performed as follows.

[0065] Given the normalized primary matrices for the left and right channels, any point in either channel can be defined as:

[0066]

[0067] Among them, the vectors of X, Y and Z correspond to any point, NPM LLL and NPM SSS The matrices correspond to the normalized main matrices of the right eye channel and the left eye channel, R L , G L and B L and R S , G S and B S The matrices correspond to the unnormalized matrices of the right eye channel and the left eye channel respectively.

[0068] The mixing functions defined in equations [1] and [2] above are substituted as the unnormalized matrices for the right eye channel and the left eye channel, respectively.

[0069]

[0070] Convert the above formula into the form of the main matrix, the formula becomes:

[0071]

[0072] in

[0073] [PM] A =[NPM] LLL [B AL ]+[NPM] SSS [B AS ]

[0074] as well as

[0075] [PM] B =[NPM] SSS [B BS ]+[NPM] LLL [B BL ]

[0076] It is known that the normalized main matrix of Rec2020 is as follows:

[0077] [NPM]_2020

[0078] The transformations from the source Rec2020 vector to gamuts A and B are:

[0079] in

[0080] as well as

[0081] in

[0082] As mentioned above, gamut A is used for lower luminance levels, while gamut B is used to achieve higher luminance levels where applicable. In contrast to the gamut scaling method where the luminance range of gamut A is the same across all channels, here the threshold vector is used as a luminance threshold, meaning that the luminance range of gamut A is different in each channel. The threshold vector representing the conversion between the "A" and "B" gamuts in the Rec2020 space can be found as follows:

[0083]

[0084] In other words, each threshold in the threshold vector is determined based on the transformation of the first virtual color gamut to the predefined color gamut. Then define the following function:

[0085] f l (P) = if (P <T P ),P, otherwise T P

[0086] f u (P) = Pf l (P)

[0087] P∈R 2020 ,G 2020 ,B 2020

[0088] The variable P represents the pixel value of the received video data, which is assumed to be tri-stimulus Rec2020 data. The function f is similar to the color gamut scaling method described above. l (P) and f u (P), function f l (P) again represents the lookup table of the color gamut A, and the function f u (P) represents the lookup table of color gamut B. In this example, function f l (P) defines a linear ramp increasing from 0 to the threshold of a specific channel defined in the threshold vector, and a flat line above the specific threshold, while the function f u (P) defines a flat line from 0 to a specific threshold, and a linear slope that increases from the specific threshold. Similarly, the specific thresholds here correspond to the brightness thresholds of each channel of the color gamut A. In some embodiments, the function f l (P) and f u (P) It is possible to define a transition other than the linear ramp described above (as long as the sum of the functions equals 1). For example, the function f l (P) and f u Either or both of (P) may define the curve as a curve to a flat line.

[0089] For each pixel value of the received video data, color gamut A and color gamut B are derived as follows:

[0090]

[0091]

[0092] In other words, for each main channel of the input video data R2020, G2020, and B2020, the brightness level is lower than the corresponding threshold value T of the threshold vector R , T G and T B Pixel values ​​that are within a certain luminance range (corresponding to gamut A) are included in gamut A, while pixel values ​​that exceed a certain threshold (meaning they are outside the luminance range of gamut A) are assigned to gamut B.

[0093] As shown in equations [3] and [4] below, any intensity values ​​of the derived color space A and color space B that are negative are then clipped to zero.

[0094]

[0095]

[0096] In some implementations, negative values ​​are clipped to 1 (or white) rather than 0. The derived gamut A and gamut B signals are then converted to the defined primaries as described above with respect to block 308 and equations [1] and [2] above.

[0097] In another embodiment, the following function is used to implement color gamut scaling:

[0098] f u (P) = PT 2020

[0099] P∈R 2020 ,G 2020 ,B 2020

[0100] In this example, the variable P represents the pixel value of the received video data, which is assumed to be tri-stimulus Rec 2020 data. Function f u (P) The upper gamut impact on the system clipping behavior is calculated and a linear ramp is defined that increases in a positive direction from a threshold for a particular channel defined in a threshold vector and decreases in a negative direction from the same threshold.

[0101] The A color gamut can be adjusted based on the residual of the B color gamut. For example, the derivation of the B color gamut is as follows:

[0102]

[0103] in

[0104] [C] B+ =max(0,[C] B )

[0105] The resulting B color gamut includes a plurality of positive pixel values ​​and a plurality of negative pixel values. The plurality of negative pixel values ​​are set to predetermined values ​​(i.e., clipped) to obtain a residual of the B color gamut, which is derived as follows:

[0106]

[0107] in

[0108] L R ,L G ,L B ∈[0,1]

[0109] In other words, any intensity value of the derived color gamut B that is a negative value is first clipped to 0. Then, any corresponding intensity value of the derived color gamut B is set to the minimum of (1) the intensity value after the clipping action or (2) a predetermined threshold value L. The predetermined threshold value can be any value between 0 and 1, such as 0.5. As an example, if the predetermined threshold value is 0.5, any intensity value above 0.5 is set to 0.5, and any intensity value below 0.5 remains the same value.

[0110] The clipped color gamut B intensity values ​​are then converted back to the defined standard color space (e.g., Rec2020) and subtracted from the original video data as defined below:

[0111]

[0112] Where R 2020 , G 2020 and B 2020 It is the R, G, B value of the video data in the defined standard color space.

[0113] Then, the color gamut A is processed based on the remaining video data within the defined standard color space:

[0114]

[0115] The maximized pixel value is then added to color gamut A to add white and bring any negative intensity values ​​back to the corresponding color gamut while maintaining the resulting hue. In some embodiments, rather than clipping any intensity values ​​of the derived color gamut B that are negative values ​​to 0, the maximized pixel value can be added to color gamut B to add white. The source white point can be calculated in color gamut A according to the following formula:

[0116]

[0117]

[0118] The minimum amount the whitepoint vector must be scaled so that all negative intensity values ​​are cleared when added to a pixel is:

[0119] Clip A =min(R Af R A_WP_RECIP ,G A G A_WP_RECIP ,B Af B A_WP_RECIP ,0)

[0120] The white point vector is scaled by this amount so that the lowest value component of gamut A is zero.

[0121]

[0122] The above equations [1] and [2] are used to calculate the driving values ​​of the first projection device 112A and the second projection device 112B respectively. These driving values ​​define the output color gamut of the projector system.

[0123] The gamut-limiting method limits the colors to the edges of the gamuts A and B, which can be created to be approximately the same for any projector system. In other words, the colors produced by one projector can be faithfully reproduced by any other kind of projector, regardless of whether the source primaries are the same.

[0124] Alternatively, a blending function may be applied to color fields A and B before clipping negative values. By applying the blending function to each color field, the values ​​of each color field are converted to the predefined primaries of the color space of the received video data. Clipping may then be applied as shown below.

[0125]

[0126]

[0127] This approach maximizes the color gamut coverage of a particular primary color for any projector system.

[0128] The output color gamut uses primarily three primary colors at low brightness and six primary colors at higher brightness. However, such a system may be prone to metameric failure, in which an observer perceives colors differently based on brightness. For example, as more color gamut B is mixed, the spectral shape of the projection system output is changed. This can be mitigated by using six primary colors as much as possible and limiting the use of three primary colors to a subset of the target color gamut. In some embodiments, this is achieved by mixing the output color gamut with the native color gamut of the projection system. The native color gamut can be a color gamut that is unique to the projector system and is based on the specific configuration of the projection system. Therefore, it may vary from projector to projector. The native color gamut is defined as a set of three primary colors Rc, Gc, Bc that equally derive long and short primary colors. For example:

[0129]

[0130] The main matrix of the color space C is defined as:

[0131]

[0132] In some embodiments, [B AL ]+[B AS ]=I3, and [B BL ]+[B BS]=I3,[PM] C Can be defined as:

[0133]

[0134] in

[0135]

[0136] To convert a vector from a defined standard color space (e.g. Rec2020) to the color gamut C:

[0137]

[0138] in

[0139]

[0140] The native drive value provided to the first projection device 112A and the second projection device 112B is determined by the following formula:

[0141]

[0142] Similar to color gamuts A and B, white can be added to the native drive value to return any negative intensity values ​​to color gamut C while maintaining the hue of the video data according to the following equation:

[0143]

[0144] There may be cases where the long gamut, short gamut, and native gamuts (L, S, and C) share the same white point (e.g., D65). In these cases, the white point and the inverse of the white point are both equal to [1, 1, 1], and the calculation of adding white to the native drive value simplifies to:

[0145]

[0146] The output drive value and the original drive value can be based on the mixing function Performs blending that returns a scalar value in [0, 1] based on some quality of the defined standard color space. For example, b can have the following form:

[0147] b=h(g(P)), where

[0148] P∈R 2020 ,G 2020 ,B 2020

[0149] is a "quality" function, and

[0150] is the "signal transfer function"

[0151] An exemplary b function is provided below:

[0152] in

[0153] is the intensity value saturation function,

[0154] are the control points of the linear signal transfer function

[0155] Therefore, the final driving value for the blend of the output color gamut and the native color gamut is:

[0156]

[0157]

[0158] In another implementation, during the calculation of the output color gamut, the output color gamut and the native color gamut are directly mixed. AL ]+[B AS ]=I3 and [B BL ]+[B BS ] = I3 (for example, using the maximum light), then:

[0159]

[0160] Therefore, driving gamuts A and B equally is equivalent to driving the long gamut and the short gamut equally. By redefining the function f accordingly l (P) and f u (P), the defined standard color space can be evenly divided between gamuts A and B:

[0161] f l (P)=if(g(P) <T 2020 ),g(P), otherwise T 2020

[0162] f u (P) = Pf l (P), where

[0163] P∈R 2020 ,G 2020 ,B 2020

[0164] g(P)=P*(1+b(P))*0.5

[0165]

[0166] Figure 4A chromaticity diagram 400 is shown. Diagram 400 includes a color gamut associated with display system 100 and a target color gamut (here Rec2020). Gamut 402 is the Rec2020 color gamut. Gamut 404 is composed of the (long) primary colors R L , G L and B L The color gamut 406 is defined by the (short) primary color R of the left eye channel. S , G S and B S Gamut 410 is a color gamut defined by the right-eye and left-eye primaries (SSS primaries). Gamut 416 is a color gamut defined by driving the primaries of the right-eye and left-eye channels with the same values ​​(a "WCG" gamut). As shown, gamut 408 is significantly different from Rec2020 gamut 402. Gamut 410 is virtual gamut A, and gamut 412 is virtual gamut B. As described above, gamut A is defined as a combination of virtual primaries to approximate Rec2020 gamut 402 as closely as possible, while gamut B is defined by the residual energy output of the virtual primaries after subtracting the energy used for gamut A. As shown, gamut A (gamut 410) more closely matches Rec2020 gamut 402 than summed gamut 408.

[0167] Figure 5A A chromaticity diagram 500A is shown, which includes the above Figure 4 402, 404, 406, 408, 410, and 412 are depicted. Chromaticity diagram 500A includes input chromaticities (chromaticities marked in black), and the resulting output chromaticities (gray) achieved using the color gamut clipping method described above. A line connecting any input chromaticity point to an output chromaticity point (e.g., a line connecting input point 502A to output point 502B) indicates how the input color is changed (if necessary). Note that in the illustrated diagram 500A, the maximum input is greater than the luminance threshold, so color gamut B is not utilized, and the second clipping method described above is used.

[0168] Figure 5B A chromaticity diagram 500B is shown, which includes the above Figure 4 The color gamuts 402, 404, 406, 408, 410 and 412 are depicted. Chromaticity diagram 500B includes input chromaticity (black) and the resulting output chromaticity (gray) achieved using the color gamut clipping method described above. In the illustrated diagram 500B, the maximum input is less than the brightness threshold, so color gamut B is utilized.

[0169] As described above, the mixing matrix is ​​a derived value determined based on the position of the primary colors compared to Rec2020. Specifically, the mixing matrix is ​​defined to place the short and long primary colors of the right and left eye channels, respectively, at specific desired positions. An example method for determining the mixing matrix for each primary color is described below.

[0170] Fig. 6A Shows Figure 4 FIG6 is an enhanced view 600A of the chromaticity diagram 400 of FIG6. As shown in view 600A, both the short red primary RS and the long red primary RL are outside the Rec2020 color gamut 402. Therefore, the color gamut A can be brought into the Rec2020 color gamut 402. In order to determine the mixing matrix for the red primary R, ​​one approach is to bind the primaries to the Rec2020 color gamut. This can be achieved by mixing the long green wavelength with the short red wavelength (RS) for color gamut A, and mixing the long red wavelength (RL) with the short red wavelength for color gamut B. By finding the minimum distance point or intersection between the resulting chromaticity and the Rec2020 boundary, the distance between the long red wavelength and the short red wavelength and the Rec2020 boundary is minimized. This position is then used to define the mixing matrix. For example, the line of the enhanced view 600A represents a mixture of long red and short green wavelengths. Point A represents the location where the mixture intersects the Rec2020 color gamut.

[0171] Another approach is to maximize the coverage of the resulting color gamut in order not to be limited by the Rec2020 color gamut. Figure 6B Shows Figure 4 600B is an enhanced view of the chromaticity diagram 400 of FIG. Here, the longest distance point from the line between the blue and green primaries of the Rec2020 color gamut to the mixture of long red (RL) and short red (RS) wavelengths. This results in the use of long red for color gamut A and short red for color gamut B.

[0172] Fig. 7A Shows Figure 4 400. As shown in view 700A, both the short green primary GS and the long green primary GL surround the Rec2020 color gamut 402. Likewise, gamut A can therefore be brought within the Rec2020 color gamut 402. Here, the primaries are bound to the Rec2020 color gamut 402 by defining the intersection of the line B between the two green primaries with the Rec2020 boundary. This location is then used to define the mixing matrix. The green point C represents the point where the gamut A green primary is located.

[0173] Another approach is to maximize the coverage of the resulting color gamut in order not to be limited by the Rec2020 color gamut. Figure 7B Shows Figure 4 700B is an enhanced view of the chromaticity diagram 400 of FIG. Here, the longest distance point from the line between the red and blue primaries of the Rec2020 color gamut to the mixture of long green (GL) and short green (GS) wavelengths. This results in the use of short green wavelengths.

[0174] Fig. 8A Shows Figure 44. An enhanced view 800A of the chromaticity diagram 400 of FIG. 400. As shown in view 800A, both the short blue primary BS and the long blue primary BL are located outside the Rec2020 color gamut 402. Both primaries are outward toward the boundary of the Rec2020 color gamut 402. Here, the primaries are bound to the Rec2020 color gamut 402 by defining the intersection of the line D between the long blue primary and the short green wavelength with the Rec2020 boundary. This position is then used to define the mixing matrix. Point E represents the point where the gamut A blue primary is located.

[0175] Another approach is to not bind the blue primary to the Rec2020 color gamut, e.g., to maximize the coverage of the resulting color gamut. Figure 8B Shows Figure 4 An enhanced view 800B of the chromaticity diagram 400 of FIG. Here, the longest distance point from the line between the red and green primaries of the Rec2020 color gamut to the mixture of the long blue (BL) and short green (GS) wavelengths is used. This position is then used to define the mixing matrix. As shown, the long blue primary is used for color gamut A, while the short blue primary is used for color gamut B.

[0176] In some embodiments disclosed in the preceding paragraphs, a threshold may be used to split the pixel RGB codeword range between the 'A' and 'B' color domains. Pixels in the 'B' color domain may then be clipped to the edge of that color domain. The residual (the portion lost due to clipping) is added back to the 'A' color domain for processing. On the other hand, in some other embodiments, a threshold may be subtracted from the input pixel to produce positive and negative values. The process then pushes these values ​​into the 'B' color domain, clips the result, and pushes the residual into the 'A' color domain. This technique makes greater use of the 'B' color domain, thus reducing overall clipping. The following sections 3-3.2 show examples of the disclosed embodiments.

[0177] In some embodiments disclosed in the previous paragraphs, a matrix is ​​applied to convert the source to the target ("A" or "B" color space), which may cause negative RGB values ​​to be clipped. In addition, hue shifts may be difficult to manage. On the other hand, in some other embodiments, a clipping method is used to represent colors that do not fit into the three-dimensional color volume. This technique preserves the hue and simply desaturates the clipped pixels. This makes the color grading process easier. When the colorist pushes the brightness or saturation and hits the edge of the three-dimensional color volume, they will simply see desaturation, which is intuitively recognizable.

[0178] The above-mentioned projection system and method can provide rendering of wide color gamut imaging.The system, method and device according to the present disclosure can adopt any one or more of the following configurations.

[0179] (1) A projection system, comprising: a first projection device; a second projection device; at least one spatial modulator; and an electronic processor, configured to: receive two-dimensional video data; generate a first plurality of intensity values ​​of a virtual primary color of a first color gamut and a second plurality of intensity values ​​of a virtual primary color of a second color gamut from the video data; subtract a brightness threshold from a plurality of pixel values ​​of the second color gamut to generate a plurality of positive pixel values ​​and a plurality of negative pixel values; set corresponding pixel values ​​of the plurality of negative pixel values ​​of the second color gamut to a predetermined value to obtain a residual of the second color gamut; add the residual of the second color gamut to the first color gamut; add the maximized pixel value to the first color gamut and the second color gamut within the two-dimensional image data to create an output color gamut; mix the output color gamut with the native color gamut of the projection system to generate a mixed color gamut; and drive the first projection device and the second projection device based on the mixed color gamut.

[0180] (2) A projection system according to (1), wherein the electronic processor is further configured to: subtract a brightness threshold from a plurality of pixel values ​​of the first color gamut to generate a second plurality of positive pixel values ​​and a second plurality of negative pixel values; and set corresponding pixel values ​​in the second plurality of negative pixel values ​​of the first color gamut to predetermined values ​​to obtain a residual of the first color gamut.

[0181] (3) A projection system according to any one of (1) or (2), wherein the first color gamut consists of a first red wavelength, a first green wavelength, and a first blue wavelength, wherein the second color gamut consists of a second red wavelength, a second green wavelength, and a second blue wavelength, wherein the first red wavelength is different from the second red wavelength, wherein the first green wavelength is different from the second green wavelength, and wherein the first blue wavelength is different from the second blue wavelength.

[0182] (4) The projection system of any one of (1) to (3), wherein a native color gamut of the projection system is a color gamut in which the projection system drives both the first color gamut and the second color gamut equally.

[0183] (5) A projection system according to any one of (1) to (4), wherein the first projection device projects a first image composed of a first mixture of a first color gamut, and wherein the second projection device projects a second image composed of a second mixture of a second color gamut.

[0184] (6) A projection system according to any one of (1) to (5), wherein the electronic processor is further configured to generate a first plurality of intensity values ​​of the virtual primary colors of the first virtual color gamut and a second plurality of intensity values ​​of the second virtual color gamut based on a comparison with the brightness threshold.

[0185] (7) A projection system according to (6), wherein the electronic processor is further configured to convert the first plurality of intensity values ​​into a third plurality of intensity values ​​of a predefined primary color of a first projection head of the display system, and to convert the second plurality of intensity values ​​into a fourth plurality of intensity values ​​of a predefined primary color of a second projection head of the display system.

[0186] (8) The projection system of any one of (1) to (7), wherein mixing the output color gamut with the native color gamut includes adding the maximized pixel value to the native color gamut.

[0187] (9) The projection system according to any one of (1) to (8), wherein the brightness threshold is a vector based on a relationship between a first color gamut and a second color gamut in a predefined color space.

[0188] (10) The projection system according to any one of (1) to (9), wherein mixing the output color gamut with the native color gamut maintains the hue of the two-dimensional video data or preserves the chromaticity of the two-dimensional video data.

[0189] (11) A method for rendering a wide color gamut image through a projection system, the projection system comprising a first projection device, a second projection device, and at least one spatial modulator, the method comprising: receiving two-dimensional video data, a first plurality of intensity values ​​of a virtual primary color of a first color gamut and a second plurality of intensity values ​​of a virtual primary color of a second color gamut, subtracting a brightness threshold from a plurality of pixel values ​​of the second color gamut to generate a plurality of positive pixel values ​​and a plurality of negative pixel values; setting corresponding pixel values ​​among the plurality of negative pixel values ​​of the second color gamut to a predetermined value to obtain a residual of the second color gamut; adding the residual of the second color gamut to the first color gamut; adding the maximized pixel value to the first color gamut and the second color gamut within the two-dimensional image data to create an output color gamut; mixing the output color gamut with a native color gamut of the projection system to generate a mixed color gamut; and driving the first projection device and the second projection device based on the mixed color gamut.

[0190] (12) According to the method described in (11), the method also includes: subtracting a brightness threshold from multiple pixel values ​​of the first color gamut to generate a second multiple positive pixel values ​​and a second multiple negative pixel values; and setting corresponding pixel values ​​in the second multiple negative pixel values ​​of the first color gamut to predetermined values ​​to obtain the residual of the first color gamut.

[0191] (13) A method according to any one of (11) or (12), wherein the first color gamut consists of a first red wavelength, a first green wavelength, and a first blue wavelength, wherein the second color gamut consists of a second red wavelength, a second green wavelength, and a second blue wavelength, wherein the first red wavelength is different from the second red wavelength, wherein the first green wavelength is different from the second green wavelength, and wherein the first blue wavelength is different from the second blue wavelength.

[0192] (14) The method of any one of (11) to (13), wherein the native color gamut of the projection system is a color gamut in which the projection system drives both the first color gamut and the second color gamut equally.

[0193] (15) A method according to any one of (11) to (14), wherein the first projection device projects a first image composed of a first mixture of a first color gamut, and wherein the second projection device projects a second image composed of a second mixture of a second color gamut.

[0194] (16) A method according to any one of (11) to (15), wherein the method also includes generating a first plurality of intensity values ​​of the virtual primary colors of the first virtual color gamut and a second plurality of intensity values ​​of the second virtual color gamut based on a comparison with the brightness threshold.

[0195] (17) A method according to (16), wherein the method also includes converting the first plurality of intensity values ​​into a third plurality of intensity values ​​of predefined primary colors of a first projection head of the display system, and converting the second plurality of intensity values ​​into a fourth plurality of intensity values ​​of predefined primary colors of a second projection head of the display system.

[0196] (18) The method of any one of (11) to (17), wherein mixing the output color gamut with the native color gamut comprises adding the maximized pixel value to the native color gamut.

[0197] (19) The projection system according to any one of (11) to (18), wherein the brightness threshold is a vector based on a relationship between a first color gamut and a second color gamut in a predefined color space.

[0198] (20) A non-transitory computer-readable medium storing instructions that, when executed by a processor of a projection system, cause the projection system to perform operations including the method according to (11).

[0199] With respect to the processes, systems, methods, heuristics, etc. described herein, it should be understood that although the steps of these processes, etc. have been described as occurring according to a particular ordered sequence, these processes may be practiced with the described steps performed in an order different from that described herein. It should also be understood that certain steps may be performed simultaneously, other steps may be added, or certain steps described herein may be omitted. In other words, the process descriptions herein are provided for the purpose of illustrating certain embodiments and should not be construed in any way as limiting the claims.

[0200] Therefore, it should be understood that the above description is illustrative, rather than restrictive. Upon reading the above description, many embodiments and applications other than the examples provided will be apparent. The scope should not be determined with reference to the above description, but rather with reference to the full scope of the appended claims and the equivalents of these claims. It is anticipated and intended that future developments will occur in the technology discussed herein, and the disclosed systems and methods will be incorporated into such future embodiments. In short, it should be understood that the present application is capable of modification and variation.

[0201] All terms used in the claims are intended to be given their broadest reasonable interpretations and their ordinary meanings as understood by those skilled in the art described herein unless an explicit indication to the contrary is made herein. In particular, use of singular articles such as "a," "the," "said," etc. should be understood to recite one or more of the indicated elements unless a claim recites an explicit limitation to the contrary.

[0202] The Abstract of the present disclosure is provided to allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. In addition, in the foregoing Detailed Description, it can be seen that various features are grouped together in various embodiments for the purpose of simplifying the present disclosure. This method of disclosure should not be interpreted as reflecting an intention that the claimed embodiments incorporate more features than are expressly recited in each claim. On the contrary, as reflected in the following claims, the inventive subject matter is less than all the features of a single disclosed embodiment. Therefore, the following claims are hereby incorporated into the Detailed Description, with each claim itself as a separately claimed subject matter.

Claims

1. A projection system capable of displaying an image using six predefined primary colors (2A, 2B, 3A, 3B, 4A, 4B) including a first set of different predefined primary colors (2A, 3A, 4A) and a second set of different predefined primary colors (2B, 3B, 4B), the projection system comprising: at least one spatial modulator (112A, 112B); and The electronic processor (205) is configured to: receiving (302) two-dimensional video data; and generating (304, 306) from the video data a first plurality of intensity values ​​of virtual primaries of a first color gamut (410) and a second plurality of intensity values ​​of virtual primaries of a second color gamut (412), the virtual primaries of the first color gamut being a first combination of the predefined primaries such that the first color gamut approximates a predefined color gamut (402), the second color gamut being defined by a residual energy output of the predefined primaries after energy of the virtual primaries of the first color gamut has been subtracted; in, The electronic processor is further configured to generate the second plurality of intensity values ​​of the virtual primary colors of the second color gamut by: subtracting a brightness threshold from each intensity value of a corresponding channel of the received video data to generate a third plurality of intensity values, the third plurality of intensity values ​​comprising a plurality of positive pixel values ​​and a plurality of negative pixel values; Setting a plurality of negative pixel values ​​of the second color gamut to predetermined values ​​to obtain a residual of the second color gamut; generating the second plurality of intensity values ​​as the residual; The electronic processor is further configured to generate the first plurality of intensity values ​​of the virtual primary colors of the first color gamut by: subtracting a second plurality of intensity values ​​converted back to the predefined color gamut (402) from the received video data to generate a remainder of the received video data; generating a fourth plurality of intensity values ​​based on the remaining portion; obtaining a vector in the first color gamut corresponding to a white point in the predetermined color gamut, and a scaling factor, eliminating all negative intensity values ​​when the vector is scaled by the scaling factor and added to the fourth plurality of intensity values; adding the vector scaled by the scaling factor to a fourth plurality of intensity values ​​to generate the first plurality of intensity values; Wherein the electronic processor is further configured to: calculating drive values ​​for at least one spatial modulator (112A, 112B) using the first plurality of intensity values ​​and the second plurality of intensity values, the drive values ​​defining an output color gamut of a projection system; blending the output color gamut with a native color gamut of the projection system, the native color gamut being defined as a set of primaries that equally drive the different first set of predefined primaries and the different second set of predefined primaries, to generate a final drive value; and At least one spatial modulator is driven based on the final drive value.

2. The projection system according to claim 1, wherein: The different first set of predefined primary colors includes a first red wavelength, a first green wavelength and a first blue wavelength, wherein the different second set of predefined primary colors includes a second red wavelength, a second green wavelength and a second blue wavelength, wherein the first red wavelength is different from the second red wavelength, wherein the first green wavelength is different from the second green wavelength, and wherein the first blue wavelength is different from the second blue wavelength.

3. The projection system according to claim 1 or 2, wherein: Blending the output color gamut with the native color gamut involves adding the maximized pixel value to the native color gamut.

4. The projection system according to claim 1 or 2, wherein: The brightness threshold is a vector based on a relationship between a first color gamut and a second color gamut in a predefined color space.

5. The projection system according to claim 1 or 2, wherein: Blending the output color gamut with the native color gamut maintains the hue of the two-dimensional video data.

6. A method of rendering a wide color gamut image by a projection system, the projection system being capable of displaying an image using six predefined primary colors (2A, 2B, 3A, 3B, 4A, 4B) including a first set of different predefined primary colors (2A, 3A, 4A) and a second set of different predefined primary colors (2B, 3B, 4B), the projection system comprising at least one spatial modulator (112A, 112B), the method comprising: receiving (302) two-dimensional video data; and generating (304, 306) from the video data a first plurality of intensity values ​​of virtual primaries of a first color gamut (410) and a second plurality of intensity values ​​of virtual primaries of a second color gamut (412), the virtual primaries of the first color gamut being a first combination of the predefined primaries such that the first color gamut approximates a predefined color gamut (402), the second color gamut being defined by a residual energy output of the predefined primaries after energy of the virtual primaries of the first color gamut has been subtracted; in, Generating the second plurality of intensity values ​​of the virtual primary colors of the second color gamut comprises: subtracting a brightness threshold from each intensity value of a corresponding channel of the received video data to generate a third plurality of intensity values, the third plurality of intensity values ​​comprising a plurality of positive pixel values ​​and a plurality of negative pixel values; Setting a plurality of negative pixel values ​​of the second color gamut to predetermined values ​​to obtain a residual of the second color gamut; generating the second plurality of intensity values ​​as the residual; The generating of the first plurality of intensity values ​​of the virtual primary color of the first color gamut comprises: subtracting a second plurality of intensity values ​​converted back to the predetermined color gamut (402) from the received video data to generate a remainder of the received video data; generating a fourth plurality of intensity values ​​based on the remaining portion; obtaining a vector in the first color gamut corresponding to a white point in the predetermined color gamut, and a scaling factor, eliminating all negative intensity values ​​when the vector is scaled by the scaling factor and added to the fourth plurality of intensity values; adding the vector scaled by the scaling factor to a fourth plurality of intensity values ​​to generate the first plurality of intensity values; calculating drive values ​​for at least one spatial modulator (112A, 112B) using the first plurality of intensity values ​​and the second plurality of intensity values, the drive values ​​defining an output color gamut of a projection system; blending the output color gamut with a native color gamut of the projection system, the native color gamut being defined as a set of primaries that equally drive the different first set of predefined primaries and the different second set of predefined primaries, to generate a final drive value; and At least one spatial modulator is driven based on the final drive value.

7. The method according to claim 6, wherein: The different first set of predefined primary colors includes a first red wavelength, a first green wavelength and a first blue wavelength, wherein the different second set of predefined primary colors includes a second red wavelength, a second green wavelength and a second blue wavelength, wherein the first red wavelength is shorter than the second red wavelength, wherein the first green wavelength is shorter than the second green wavelength, and wherein the first blue wavelength is shorter than the second blue wavelength.

8. The method according to claim 6 or 7, wherein: Blending the output color gamut with the native color gamut involves adding the maximized pixel value to the native color gamut.

9. The method according to claim 6 or 7, wherein: The brightness threshold is a vector based on a relationship between a first color gamut and a second color gamut in a predefined color space.

10. The method according to claim 6 or 7, wherein: Mixing the output color space with the native color space preserves the hue of the 2D video data.

11. A non-transitory computer readable medium storing instructions, which, when executed by a processor of a projection system according to any one of claims 1-5, cause the projection system to perform operations including the method according to any one of claims 6-10.

12. A device for rendering a wide color gamut image, comprising: one or more processors; and One or more non-transitory storage media having instructions stored thereon, which when executed by one or more processors cause the one or more processors to perform the method according to any one of claims 6 to 10.

13. An apparatus comprising means for performing the method according to any one of claims 6 to 10.

14. A computer program product having instructions which, when executed by a computing device or system, cause the computing device or system to perform the method according to any one of claims 6 to 10.

Images