Ambient display adaptation for privacy screens
10176781 ยท 2019-01-08
Assignee
Inventors
Cpc classification
G09G2320/0666
PHYSICS
International classification
Abstract
A display device is used in conjunction with: (1) optical sensors to collect information about ambient conditions in the environment of a viewer of the display device; and/or (2) privacy element identification and detection mechanisms (PEDMs) to collect information about the presence, orientation, and/or type of privacy elements being used in conjunction with the display device. For one embodiment, a processor in communication with the display device may create a view model based, at least in part, on the predicted effects of the ambient environmental conditions and/or presence of privacy elements being used in conjunction with the display device on the user's viewing experience. The view model may be a function of gamma, black point, white point, privacy element orientation and/or type, backlighting, field of view, number of viewers, color offset, or a combination thereof. The view model is also referred to as an ambient/privacy model.
Claims
1. A method, comprising: receiving first visually perceptible data to be presented by a display device; receiving second data indicative of one or more characteristics of the display device; receiving third data indicative of ambient light conditions in the display device's environment; determine an ID of a privacy element coupled to the display device by using one or more privacy element identification and detection mechanisms (PEDMs) embedded in the display device; creating a view model based, at least in part, on the received second data, the received third data, and fourth data determined to be associated with the privacy element based on the determined ID, wherein the view model comprises an adjustment to one or more operational characteristics of the display device; adjusting the display device based on the created view model; and displaying, by the adjusted display device, the first data.
2. The method of claim 1, wherein the adjustment to the one or more operational characteristics of the display device comprises one or more determined adjustments to a brightness, gamma, white point, black point, reflectivity, field of view, color offset, or a combination thereof, of the display device based, at least in part, on the received second data, the received third data, and the fourth data.
3. The method of claim 2, wherein the adjustment to the one or more operational characteristics of the display device further comprise one or more determined adjustments to the display device based on a determination that one or more optical sensors used to acquire the third data are at least partially occluded by one or more privacy elements.
4. The method of claim 1, further comprising receiving the fourth data from at least one of: (i) the one or more PEDMs; and (ii) a data store communicatively coupled to the one or more PEDMs.
5. The method of claim 4, wherein receiving the fourth data further comprises determining a type or an orientation of the privacy element coupled to the display device, and wherein the adjustment to the one or more operational characteristics of the display device further comprise one or more determined adjustments to the display device based on the determination of the type or the orientation of the privacy element.
6. The method of claim 4, wherein the adjustment to the one or more operational characteristics of the display device further comprise one or more determined adjustments to the display device based on a determination that the received fourth data includes a request for the display device to enter a private mode, and wherein the request is based, at least in part, on the one or more PEDMs.
7. The method of claim 1, wherein the one or more PEDMs comprise one or more of a sensor and an RFID tag.
8. The method of claim 1, wherein the privacy element is coupled to the display device using one or more magnets.
9. An apparatus, comprising: a display device; one or more optical sensors; one or more privacy element identification and detection mechanisms (PEDMs) embedded in the display device; memory operatively coupled to the one or more optical sensors and the one or more PEDMs, wherein the memory stores instructions; and a processor operatively coupled to the display device, the memory, the one or more optical sensors, and the one or more PEDMs, wherein execution of the stored instructions by the processor causes the processor to: receive first data to be presented by the display device, wherein the first data is visually perceptible; receive second data indicative of one or more characteristics of the display device; receive third data indicative of ambient light conditions in the display device's environment; determine an ID of a privacy element coupled to the display device by using the one or more PEDMs; create a view model based, at least in part, on the received second data, the received third data, and fourth data determined to be associated with the privacy element based on the determined ID, wherein the view model comprises an adjustment to one or more operational characteristics of the display device; adjust the display device based on the created view model; and display, by the adjusted display device, the first data.
10. The apparatus of claim 9, wherein the adjustment to the one or more operational characteristics of the display device comprises one or more determined adjustments to a brightness, gamma, white point, black point, reflectivity, field of view, color offset, or a combination thereof, of the display device based, at least in part, on the received second data, the received third data, and the fourth data.
11. The apparatus of claim 10, wherein the adjustment to the one or more operational characteristics of the display device further comprises one or more determined adjustments to the display device based on a determination that the one or more optical sensors used to acquire the third data are at least partially occluded by one or more privacy elements.
12. The apparatus of claim 9, wherein execution of the stored instructions by the processor further causes the processor to receive the fourth data from at least one of: (i) the one or more PEDMs; and (ii) a data store communicatively coupled to the one or more PEDMS.
13. The apparatus of claim 12, wherein the instructions executed by the processor to cause the processor to receive the fourth data further comprises instructions executed by the processor to cause the processor to determine a type or an orientation of the privacy element coupled to the display device, and wherein the adjustment to the one or more operational characteristics of the display device further comprises one or more determined adjustments to the display device based on the determination of the type or the orientation of the privacy element.
14. The apparatus of claim 12, wherein the adjustment to the one or more operational characteristics of the display device further comprises one or more determined adjustments to the display device based on a determination that the received fourth data includes a request for the display device to enter a private mode, and wherein the request is based, at least in part, on the one or more PEDMs.
15. The apparatus of claim 9, wherein the one or more PEDMs comprise one or more of a sensor and an RFID tag.
16. The apparatus of claim 9, wherein the privacy element is coupled to the display device using one or more magnets.
17. A non-transitory computer-readable storage medium storing instructions, which when executed by a processor, cause the processor to: receive first data to be presented by a display device, wherein the first data is visually perceptible; receive second data indicative of one or more characteristics of the display device; receive third data indicative of ambient light conditions in the display device's environment; determine an ID of a privacy element coupled to the display device by using one or more privacy element identification and detection mechanisms (PEDMs) embedded in the display device; create a view model based, at least in part, on the received second data, the received third data, and fourth data determined to be associated with the privacy element based on the determined ID, wherein the view model comprises an adjustment to one or more operational characteristics of the display device; adjust the display device based on the created view model; and display, by the adjusted display device, the first data.
18. The non-transitory computer-readable storage medium of claim 17, wherein the adjustment to the one or more operational characteristics of the display device comprises one or more determined adjustments to a brightness, gamma, white point, black point, reflectivity, field of view, color offset, or a combination thereof, of the display device based, at least in part, on the received second data, the received third data, and the fourth data.
19. The non-transitory computer-readable storage medium of claim 17, wherein the adjustment to the one or more operational characteristics of the display device further comprises one or more determined adjustments to the display device based on a determination that one or more optical sensors used to acquire the third data are at least partially occluded by one or more privacy elements.
20. The non-transitory computer-readable storage medium of claim 17, wherein execution of the stored instructions by the processor further causes the processor to receive the fourth data from at least one of: (i) the one or more PEDMs; and (ii) a data store communicatively coupled to the one or more PEDMs.
21. The non-transitory computer-readable storage medium of claim 20, wherein the instructions, which when executed by the processor, cause the processor to receive the fourth data further comprises instructions, which when executed by the processor, cause the processor to determine a type or an orientation of the privacy element coupled to the display device, and wherein the adjustment to the one or more operational characteristics of the display device further comprises one or more determined adjustments to the display device based on the determination of the type or the orientation of the privacy element.
22. The non-transitory computer-readable storage medium of claim 20, wherein the adjustment to the one or more operational characteristics of the display device further comprises one or more determined adjustments to the display device based on a determination that the received fourth data includes a request for the display device to enter a private mode, and wherein the request is based, at least in part, on the one or more PEDMs.
23. The non-transitory computer-readable storage medium of claim 17, wherein the one or more PEDMs comprise one or more of a sensor and an RFID tag.
24. The non-transitory computer-readable storage medium of claim 17, wherein the privacy element is coupled to the display device using one or more magnets.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DETAILED DESCRIPTION
(13) This disclosure pertains to techniques for using a display device in conjunction with: (1) various optical sensors (e.g., an ambient light sensor, an image sensor, or a video camera, etc.) to collect information about the ambient conditions in the environment of a viewer of the display device; and/or (2) various privacy element identification and detection mechanisms (PEDMs)e.g., Hall effect sensors, other sensors, etc.to collect information about the presence, orientation, and/or type of privacy elements being used in conjunction with the display device in order to create an ambient/privacy model. The ambient/privacy model is also referred to herein as a view model. In one embodiment, the ambient/privacy model is used to enhance or adjust one or more properties of the display device based on at least one of the following: (i) the ambient conditions in which the display is being viewed; or (ii) the privacy elements being used in conjunction with the display device. The ambient/privacy model may be a function of gamma, black point, white point, privacy element orientation and/or type, backlighting, field of view, number of viewers, color offset, or a combination thereof.
(14) This disclosure discusses techniques for creating ambient/privacy element-aware models to dynamically adjust a device display so as to present a consistent visual experience across various environments in which the display is being viewed and/or with respect to the various privacy elements that may be being used in conjunction with the display device. One of ordinary skill in the art would recognize that the techniques disclosed may also be applied to other contexts and applications as well. The techniques disclosed herein are applicable to any number of electronic devices with optical sensors and displays that are amenable to being utilized in conjunction with privacy elements. Illustrative privacy elements include, but are not limited to, digital cameras, digital video cameras, mobile phones, personal data assistants (PDAs), portable music players, monitors, televisions, and, of course, desktop, laptop, and tablet computer displays.
(15) In the interest of clarity, not all features of an actual implementation are described in this specification. It will of course be appreciated that in the development of any such actual implementation (as in any development project), numerous decisions must be made to achieve the developers' specific goals (e.g., compliance with system- and business-related constraints), and that these goals will vary from one implementation to another. It will be appreciated that such development effort might be complex and time-consuming, but would nevertheless be a routine undertaking for those of ordinary skill having the benefit of this disclosure. Moreover, the language used in this disclosure has been principally selected for readability and instructional purposes, and may not have been selected to delineate or circumscribe the inventive subject matter, resort to the claims being necessary to determine such inventive subject matter. Reference in the specification to one embodiment or to an embodiment means that a particular feature, structure, or characteristic described in connection with the embodiments is included in at least one embodiment of the invention, and multiple references to one embodiment or an embodiment should not be understood as necessarily all referring to the same embodiment.
(16) Referring now to
(17) As is known in technology fields related to display devices and human perception modeling, the use of gamma encoding maps linear display data (e.g., source content 100) into a more perceptually uniform domain. Gamma adjustment, or, as it is often simply referred to, gamma, is the name given to the nonlinear operations commonly used to encode linear luma values. Gamma, , may be defined by the following simple power-law expression: L.sub.out=L.sub.in.sup., where the input and output values, L.sub.in and L.sub.out, respectively, are typically non-negative real values occurring over a predetermined range, e.g., zero to one. A gamma value greater than one is sometimes called an encoding gamma, and the process of encoding with this compressive power-law nonlinearity is called gamma compression. Conversely, a gamma value less than one is sometimes called a decoding gamma, and the application of the expansive power-law nonlinearity is called gamma expansion.
(18) In some scenarios, e.g., in extended range representations, negative values may also be used (both in the linear and gamma-encoded spaces) to encode colors that are outside of the nominal gamut defined by the usual primaries used to describe a color space (e.g., a color more saturated than a logical sum of the primaries may be mathematically represented as a color with one or morebut not allcomponents negative). For instance, to make a more saturated than 1,0,0 sRGB red, one could remove some of the sRGB red color's green and/or blue pollution using negative green and/or negative blue component values. The matrix math used to translate colors between color spaces will automatically generate values outside of the nominal (0,1) range, but they are usually truncated. Values greater than 1.0 may also represent higher dynamic range values.
(19) Another way to think about the gamma characteristic of system 112 is as a power-law relationship that approximates the relationship between the encoded luma in the system 112 and the actual desired image luminance on whatever the eventual user display device is (e.g., display 114). Other uses of gamma may include: encoding between the physical world and media; decoding media data to linear space; and converting display linear data to the display's response space.
(20) Information relating to the source content 100 and source profile 102 may be sent to viewer 116's device containing the system 112 for performing gamma adjustment utilizing a LUT 110. Viewer 116's device may comprise, for example, a mobile phone, PDA, portable music player, monitor, television, or a laptop, desktop, or tablet computer. Upon receiving the source content 100 and source profile 102, system 112 may perform a color adaptation process 106 on the received data, e.g., utilizing the COLORSYNC framework. (COLORSYNC is a registered trademark of Apple Inc.) COLORSYNC provides several different techniques to perform gamut mapping, i.e., color matching across various color spaces. For instance, perceptual matching tries to preserve as closely as possible the relative relationships between colors, even if all the colors must be systematically distorted.
(21) Once the color profiles of the source and destination have been appropriately adapted, image values (e.g., red, green, and blue pixel values or luma values, etc.) may enter the framebuffer 108. The framebuffer 108 may be defined as a video output device that drives a video display from a memory buffer containing a complete frame of, in this case, image data of source content 100 that is processed using the process 106. In system 112, a computer processor or other suitable programmable control device (not shown) may perform gamma adjustment computations for display device 114 based on the native luminance response (often called the EOTF, or electrical optical transfer function) of the display device 114, the color gamut of the display device 114, and white point information associated with the display device 114 (that may be stored in the source profile 102), as well as the source profile 102 attached to the source content 100 to specify the content's rendering intent.
(22) As explained above, the image values of the source content 100 entering framebuffer 108 may already have been processed by the color adaptation process 106 and/or one or more applications (not shown). These images values may have a specific implicit gamma that is based on a Framebuffer Gamma function, as will be described in more detail below. In some scenarios, the image values may need to be converted into linear space so that additional operations may be performed on the data before the data is inverted back to non-linear space for display. In other scenarios, the image values may undergo linear space scaling, color space conversion, and/or compositing before entering framebuffer 108. In still other scenarios, some operations may also be performed on the image values after exiting the framebuffer 108. For example, a color space conversion may be used to convert image values from a canonical framebuffer color space to a specific color space of the display, e.g., a panel fit scale.
(23) System 112 may then utilize a Look Up Table (LUT) 110 to perform a so-called gamma adjustment process. The implicit gamma of the values entering the framebuffer 108 can be visualized by looking at a Framebuffer Gamma Function that is ideally an inverse of a Native Display Response function associated with the display device 114. The Native Display Response Function can be used to characterize the luminance response of the display 114 to input, to yield unity system response. However, because the inverse of the Native Display Response isn't always exactly the inverse of the framebuffer, the LUT 110sometimes implemented on a processing unit (e.g., a GPU)may be used to transform the data in order to accommodate imperfections in the relationship between the encoding gamma and decoding gamma values, as well as the particular luminance response characteristics of the display device 114.
(24) LUT 110 may comprise a two-column table of positive, real values spanning a particular range, e.g., from zero to one. First column values may correspond to an input image value, whereas the corresponding second column values may correspond to an output image value that the input image value will be transformed into before being ultimately being displayed on display 114. LUT 110 may be used to account for the imperfections in the display 114's luminance response curve, also known as a transfer function, or EOTF. In other scenarios, an LUT may have separate channels for each primary color in a color space, e.g., an LUT may have Red, Green, and Blue channels in the sRGB color space.
(25) In some scenarios, the goal of gamma adjustment system 112 is to have an overall 1.0 gamma boost applied to the content that is being displayed on the display device 114. An overall 1.0 gamma boost corresponds to a linear relationship between the input encoded luma values and the output luminance on the display device 114. Ideally, an overall 1.0 gamma boost will correspond to the source author's intended view of the content presented on the display device 114.
(26) The transformation applied by the LUT 110 to the data from framebuffer 108 before the data is output to the display device 114 ensures the desired 1.0 gamma boost on the eventual display device 114. This is generally a good outcome, although it does not take into account the effect on the viewer 116's perception of gamma due to differences in ambient light conditions. In other words, the 1.0 system gamma boost may only appropriate in one ambient lighting environment. Furthermore, the transformation applied by the LUT 110 to the data from framebuffer 108 before the data is output to the display device 114 does not take into account the effect on the viewer 116's perception of gamma due to the presence of one or more privacy elements (not shown) being used in conjunction with the display device 114. Examples of privacy elements includes, but are not limited to, a detachable privacy screen, anti-glare filter, or similar overlay.
(27) Referring now to
(28) With regard to the graph 202, the abscissae on the horizontal axis of the graph of the Native Display Response Function 202 represent input image values spanning a particular range, e.g., from zero to one. The ordinates on the vertical axis of the graph of the Native Display Response Function 202 represent output image values spanning a particular range, e.g., from zero to one. In theory, systems (e.g., the system 112 in
(29) Referring now to
(30) Referring now to
(31) One phenomenon in particular, known as diffuse reflection, may play a particular role in a viewer's perception of a display device. Diffuse reflection may be described as the reflection of light from a surface such that an incident light ray is reflected at many angles. Thus, one of the effects of diffuse reflection is that, in instances where the intensity of the diffusely reflected light rays is greater than the intensity of light projected out from the display in a particular region of the display, the viewer will not be able to perceive tonal details in those regions of this display. This effect is illustrated by dashed line 406 in
(32) A front-facing image sensor provides information regarding how much light is hitting the display surface. This information may be used in conjunction with a model of the reflective and diffuse characteristics of the display to determine where the black point is for the particular lighting conditions the display is currently in. Although optical sensor 404 is shown as a front-facing image sensor, i.e., facing in the general direction of the viewer 116 of the display device 402, other optical sensor placements and positioning are possible. For example, one or more back-facing image sensors alone (or in conjunction with one or more front facing sensors) could give even further information about light sources and color in the viewer's environment. The back-facing sensor picks up light re-reflected off objects behind the display and may be used to determine the brightness of the display's surroundings. This information may be used to adapt the display's gamma function. For example, the color of wall 412, if it fills enough of the viewer's field of vision 402 could have a profound effect on the viewer's perception. Likewise, in the example of an outdoor environment, the color of light surrounding the viewer can make the display appear differently than it would in an indoor environment with neutral colored lighting.
(33) In one embodiment, the optical sensor 404 may comprise a video camera capable of capturing spatial information, color information, and intensity information. Thus, utilizing a video camera could allow for the creation of an ambient model that could adapt not only the gamma and black point of the display device, but also the display device's white point. This may be advantageous because fixed white point systems are not generally ideal when displays are viewed in environments of varying ambient lighting levels and conditions. In some embodiments, a video camera may be configured to capture images of the surrounding environment for analysis at some predetermined time interval, e.g., every ten seconds, thus allowing the ambient/privacy model to be gradually updated as the ambient conditions (including the presence, or lack thereof, of a privacy element) in the viewer's environment change (causing the viewer's perception to change). The rate of adaptation ideally should match the rate of the viewer's perceptual adaptation (perceptual adaptation is asymmetric with respect to environmental brightening or darkening).
(34) Additionally, a back-facing video camera intended to model the surroundings could be designed to have a field of view roughly consistent with the calculated or estimated field of view of a viewer. Once the field of view of the viewer is calculated or estimatede.g., based on the size or location of the viewer's facial features as recorded by a front-facing camera, assuming the native field of view of the back-facing camera is known and is larger than the field of view of the viewerthe system may then determine what portion of the back-facing camera image to use for updating the ambient/privacy model. This surround cropping technique may also be applied to the white point computation for the viewer's surroundings.
(35) Referring now to
(36) Referring now to
(37) Viewers 612A-612C are located at different viewing angles 606/608 to display device 602. Center point 610 represents the center of display device 602. Thus, it can be seen that viewer 612A is at a zero-offset angle from center point 610, whereas viewer 612B is at an offset angle 606 from center point 610, and viewer 612C is at an offset angle 608 from center point 610. For the purposes of this example, viewer 612A will be considered the authorized user/owner of display device 602. In one embodiment, sensor 604 may be an image sensor or video camera capable of performing facial detection and/or facial analysis by locating the eyes of a particular viewer 612 and calculating the distance 614 from the display to the viewer, as well as the viewing angle 606/608 of the viewer to the display.
(38) These determinations could enable an ambient/privacy element-aware model for dynamically adjusting a display's characteristic to determine how much of the authorized user's view is taken up by the device display. Further, by determining what angle the authorized viewer is at with respect to the device display, a GPU-based transformation may be applied to further tailor the display's characteristics to the authorized viewer's position (e.g., gamma, black point, white point). All of this can lead to a more accurate depiction of the source author's original intent and an improved and consistent viewing experience for the authorized viewer, potentially at the expense of the viewing conditions for unauthorized viewers 612B and 612C, as shown in the example of
(39) Also shown as part of the exemplary display device 602 of
(40) In some embodiments, the privacy screen 618A could be adapted to use magnets 620 (represented by solid-black rectangles) to easily and unobtrusively attach to the display device's corresponding embedded magnets located at the respective positions of PEDMs 616A-616D without the need to glue plastic stays (or the like) to the display device around the perimeter of the display (i.e., an auto alignment mechanism). As shown in
(41) According to some embodiments, the magnets 620 in the privacy screen 618 could be read by the Hall effect sensors 616 (or other suitable PEDM) embedded in the display device 602 to detect a unique ID that may then be used as an index into a privacy element database that identifies the exact type of privacy screen 618 and one or more characteristics of the privacy screen 618 with regard to the display device 603. The one or more characteristics of the privacy screen 618 with regard to the display device 603 can be referred to herein as one or more PEDM parameters. For one embodiment, the PEDMs include one or more sensors, one or more RFID tags, and associated circuitry for acquiring reflectance, light loss, white shift (or color shift of white light), field of view, and any other information related to an operation of the privacy screen 618 when it is used with the display device 603. For this embodiment, the unique ID can be associated with the PEDM parameters, such that the determination of the unique ID includes acquiring the PEDM parameters using the PEDMs. For a further embodiment, the PEDMs can include (or be associated with) memory for storing the unique ID and/or the one or more PEDM parameters acquired using the PEDMs. In this way, the unique ID and/or the one or more acquired PEDM parameters can be read directly from the PEDMs. Also, and for an even further embodiment, the unique ID and/or the one or more acquired PEDM parameters can be communicated by the PEDMs to an external data store (e.g., cloud-based storage, a server, etc.) via one or more communication mechanisms (e.g., a network and its corresponding networking equipment, etc.). For another embodiment, the unique ID can be used as an index into the privacy element database to acquire the one or more PEDM parameters from the privacy element database. For this embodiment, the one or more PEDM parameters can be acquired via testing or may be obtained from a manufacturer of the privacy screen 618 and/or a manufacturer of the display device 603. For a further version of the immediately preceding embodiment, the privacy element database can be in an external data store (e.g., cloud-based storage, a server, etc.) that is accessed by the PEDMs via one or more communication mechanisms (e.g., a network and its corresponding networking equipment, etc.).
(42) A combined ambient/privacy model could then use this information (or an index to a database of such information) to perform adaptation to the display that is currently being viewed in conjunction with such a privacy screen (in terms of brightness, reflectivity, white point, black point, field of view, etc.). Such a system could further be adapt to compensate for any color shifting introduced by the privacy screen. Further, the ambient/privacy model could adapt the ambient light sensor, and even the display device's camera results to potentially account for being filtered through the privacy screen. Even without a mechanism for automatically identifying the particular type of privacy element present, the ambient/privacy model could be further extended to incorporate a database of common display privacy elements for a user to select from among, or provide a user interface (UI) that would allow the user to tune the display to appear correct with the particular type of privacy screen currently being used in conjunction with the display device.
(43) Also shown in
(44) Turning now to
(45) In still other embodiments, the user's indication that the he or she wishes the device to be operating in PRIVATE mode may affect other parts of the display device's operating system. For example, the system could go into a Do Not Disturb mode where notifications or other events are suppressed or filtered, so that they are not immediately noticeably raised to the user. In yet other embodiments, the display screen itself may be altered to simulate the effects of a privacy screen without a physical privacy screen actually being put in communication with the display device, e.g., by using two independently-controlled LCD devices overlaid one another as part of the display device's display surface.
(46) Referring now to
(47) One embodiment of an ambient/privacy element-aware model for dynamically adjusting a display's characteristic disclosed herein takes information from one or more optical sensors (e.g., sensor 404), information regarding the presence, orientation, and/or type of privacy elements in conjunction with the display device, and display profile 104 and makes a prediction such effects have on viewing conditions and the viewer's perception due to such conditions. The result of that prediction may be used to determine how system 700 modifies the LUT, such that it serves as an ambient/privacy-aware LUT 702. In one embodiment, LUT modifications may comprise modifications to add or remove gamma from the system or to modify the black point or white point of the system. Perceptual black may be described as the level of light intensity below which no further detail may be perceived by a viewer. White point may be described as the set of values that serve to define the color white in the color space.
(48) In one embodiment, the black level for a given ambient environment may be determined, e.g., by using an ambient light sensor 404 or by taking measurements from the display device's actual panel and/or diffuser. As mentioned above in reference to
(49) In another embodiment, the white point for a given ambient environment may be determined, e.g., by using an image sensor or video camera to determine the white point in the viewer's surroundings by analyzing the lighting and color conditions of the ambient environment. The white point for the display device may then be adapted to be the determined white point from the viewer's surroundings. In one particular embodiment, this modification, or white point adaptation, may be performed by stretching or otherwise modifying the values in the LUT such that the color white for the display is defined by finding the appropriate white point in the user's ambient environment. Additionally, modifications to the white point may be asymmetric between the LUT's Red, Green, and Blue channels, thereby moving the relative RGB mixture, and hence the white point.
(50) In another embodiment, a color appearance model (CAM), such as the CIECAM02 color appearance model, provides the appropriate gamma boost based on the brightness and white point of the user's surroundings, as well as the field of view of the display subtended by the user's field of vision. In some embodiments, knowledge of the size of the display and the distance between the display and the user may also serve as useful inputs to the model. Information about the distance between the display and the user could be retrieved from a front-facing image sensor, such as front-facing camera 404. For example, for pitch black ambient environments an additional gamma boost of about 1.5 imposed by the LUT may be appropriate, whereas a 1.0 gamma boost (i.e., unity, or no boost) may be appropriate for a bright or sun-lit environment. For intermediate surroundings, appropriate gamma boost values to be imposed by the LUT may be interpolated between the values of 1.0 and about 1.5. A more detailed model of surrounding conditions that can be used together with the embodiments described in connection with
(51) In the embodiments described immediately above, the LUT 702 serves as a useful and efficient place for system 700 to impose these supplemental ambient/privacy element-based transformations on the input source data. It may be beneficial to use the LUT to implement these ambient/privacy element-based transformations because the LUT: (1) is easily modifiable, and thus convenient; (2) changes properties for the entire display device; (3) won't add any additional runtime overhead to the system; and (4) is already used to carry out similar style transformations for other purposes, as described above. In other embodiments, the adjustments determined by ambient/privacy model 704 may be applied through an enhanced color adaptation model 706. In some embodiments of an enhanced color adaptation model, gamma-encoded source data may first undergo linearization to remove the encoded gamma. At that point, gamut mapping may take place, e.g., via a color adaptation matrix. In the enhanced color adaptation model it may be beneficial to adjust the white point of the system based on the viewer's surroundings while mapping other color values to the gamut of the display device. Next, the black point compensation for the system could be performed to compensate for the effects of diffusive reflection. At this point in the enhanced color adaptation model, the already color-adapted data may be gamma encoded again based on the display device's characteristics with the additional gamma boost suggested by the CAM due to the user's surroundings. Finally, the data may be processed by the LUT and sent to the display. In those embodiments where adjustments determined by ambient/privacy model 704 are applied through the enhanced color adaptation model 706, no further modifications of the device's LUT table are necessary. In certain circumstances, it may be advantageous to impose the adjustments determined by ambient/privacy model 704 through the enhanced color adaptation model 706 rather than LUT. For example, adjusting the black point compensation during the color adaption stage could allow for the use of dithering to mitigate banding in the resultant display. Further, setting the white point while in linear space, i.e., at the time of gamut mapping, may be preferable to setting the white point using gamma encoded data, e.g., because of the ease of performing matrix operations in the linear domain, although transformations may also be performed in the non-linear domain, if needed.
(52) Referring now to
(53) The overall goal of some color adaptation models may be to understand how the source material is ideally intended to look on a viewer's display. In a typical scenario for video, the ideal viewing conditions may be modeled as a broadcast monitor in a dim broadcast studio environment lit by 16 lux of CIE Standard Illuminant D65 light. This source rendering intent may be modeled, e.g., by attaching an ICC profile to the source. The attachment of a profile to the source data may allow the display device to interpret and render the content according to the source creator's rendering intent. Once the rendering intent has been determined, the display device may determine how to transform the source content to make it match the ideal appearance on the display device, which may (and likely will) be a non-broadcast monitor, in an environment lit by non-D65 light, and with something other than 16 lux ambient lighting.
(54) Referring now to
(55) Referring now to
(56) Referring now to
(57) Referring now to
(58) Storage device 1265 may store media (e.g., image and video files), software (e.g., for implementing various functions on device 1200), preference information, device profile information, and any other suitable data. Storage device 1265 may include one more storage mediums, including for example, a hard-drive, permanent memory such as ROM, semi-permanent memory such as RAM, or cache.
(59) Memory 1260 may include one or more different types of memory which may be used for performing device functions. For example, memory 1260 may include cache, ROM, and/or RAM. Communications bus 1270 may provide a data transfer path for transferring data to, from, or between at least storage device 1265, memory 1260, and processor 1205. User interface 1215 may allow a user to interact with the electronic device 1200. For example, the user input device 1215 can take a variety of forms, such as a button, keypad, dial, a click wheel, or a touchscreen.
(60) In one embodiment, the personal electronic device 1200 may be an electronic device capable of processing and displaying media such as image and video files. For example, the personal electronic device 1200 may be a device such as such a mobile phone, personal data assistant (PDA), portable music player, monitor, television, laptop, desktop, and tablet computer, or other suitable personal device.
(61) The foregoing description of preferred and other embodiments is not intended to limit or restrict the scope or applicability of the inventive concepts conceived of by the Applicants. As one example, although the present disclosure focused on desktop computer display screens, it will be appreciated that the teachings of the present disclosure can be applied to other implementations, such as portable and/or handheld electronic devices with display screens with which privacy screens may be utilized. In exchange for disclosing the inventive concepts contained herein, the Applicants desire all patent rights afforded by the appended claims. Therefore, it is intended that the appended claims include all modifications and alterations to the full extent that they come within the scope of the following claims or the equivalents thereof.