EP1858002A1

EP1858002A1 - Apparatus and method for adjustment of one or more picture parameters of a display device

Info

Publication number: EP1858002A1
Application number: EP06252524A
Authority: EP
Inventors: Huseyin Vestel Elektronik Sanayi ve Bashan
Original assignee: Vestel Elektronik Sanayi ve Ticaret AS
Current assignee: Vestel Elektronik Sanayi ve Ticaret AS
Priority date: 2006-05-15
Filing date: 2006-05-15
Publication date: 2007-11-21

Abstract

The invention provides a method of adjusting a picture parameter for displaying an image on a display device, the method comprising: storing for each user parameters to characterise user preference for the values for two or more picture parameters; on identification of a particular user, determining at least one range for presentation to the user to enable a user selection of the value for the picture parameter in dependence on the stored user characterisation.

Description

The invention relates to an apparatus and method for adjustment of one or more picture parameters of a display device.
Examples of display devices to which the present invention may relate include a cathode ray tube display device, a plasma display device, an LCD display device or indeed any display device in which the ambient light conditions may have an effect on the ease or comfort etc of viewing an image thereon. In an embodiment, the invention relates to an apparatus and a method for enabling the training of picture parameters automatically in response to ambient light.
US-A-6,947,017 relates to a portable computer system that comprises dynamically adjustable brightness range settings and a brightness control for providing improved user readability and prolonged component life time of a display screen of the computer system. Examples of computer systems to which this patent relates include personal digital assistance (PDA) or other such portable computer systems. They are, therefore, exceptionally portable.
The systems, and others like them, have in common some type of screen for displaying images as part of a user interface. The images could be graphic display images or may be the display of word processing, e-mail or other text-based packages. Example of types of display device that may be used in such devices include liquid crystal displays (LCD). The system includes a light sensor and display controller. The display controller serves to adjust range settings for display brightness based on ambient light information signals received from the light sensor. In the example described, there are a number of stored, predetermined ranges of screen brightness and the system is arranged to vary the brightness of the display within the constraints of one of the ranges at any time, the particular range selected in dependence on the ambient light level.
According to a first aspect of the present invention, there is provided a method of adjusting a picture parameter for displaying an image on a display device, the method comprising: storing for each user parameters to characterise user preference for the values for at least one more picture parameter; on identification of a particular user, determining at least one range for presentation to the user to enable a user selection, e.g. an accurate selection, of the value for one or more of the at least one picture parameter in dependence on the stored user characterisation.
According to a second aspect of the present invention, there is provided a method for adjustment of one or more picture parameters of an image for display on a display device, the method comprising: either, in response to receipt of a user preference for the value of a first picture parameter of the image automatically determining and/or adjusting the available range of at least one picture parameter of the image; or, upon identification of a user, automatically updating one or more picture parameters in dependence on characterising parameters for that identified user and ambient light levels.
According to a third aspect of the present invention, there is provided apparatus for adjusting one or more picture parameters, the apparatus comprising: a processor for receiving user inputs; memory for storing characterising parameters previously determined for particular users in dependence on the user; and a range determination unit for receiving a user identifier and in dependence on the user identifier providing the ranges of that user for display.
According to a fourth aspect of the present invention, there is provided apparatus for adjustment of one or more picture parameters of an image for display on a display device, the apparatus being arranged in response to receipt of a user preference for the value of a first picture parameter of the image automatically and dynamically in response to variation in ambient light level to determine and/or adjust the available range of at least one picture parameter of the image.
According to a fifth aspect of the present invention, there is provided a method for adjustment of one or more picture parameters of an image for display on a display device, the method comprising: in accordance with the characterization of user-preferred picture values in response to changes in ambient light conditions and automatically determined values for the picture parameters corresponding to a particular ambient light level, automatically determining and/or adjusting the available range of at least one picture parameter of the image.
Preferably, the method comprises upon receipt of a user indication of a desired variation in a picture parameter, updating the characterization of user-preferred picture values in response to changes in ambient light conditions and storing said updated characterisation as a set of User System Parameters.
Preferably, the available range for the picture parameter for which the user has provided his/her preferred setting is updated too.
Preferably, a picture parameter adjustment system is provided and is arranged to generate automatically updated values of picture parameters in dependence on variations in ambient light levels and the User System Parameters for the user using the system.
According to a sixth aspect of the present invention, there is provided apparatus for adjustment of one or more picture parameters of an image for display on a display device, the apparatus comprising: an ambient light sensor for determining the level of ambient light; memory for storing user system parameters to characterise a user's sensibilities and preferences regarding picture parameters in dependence on ambient light levels; and a picture parameter adjustment unit for automatically determining the required value for one or more picture parameters in dependence on the ambient light level and the user system parameters.
According to a seventh aspect of the present invention, there is provided a method for providing user-adaptive range determination for the values of one or more picture parameters for display on a display device, the method comprising: continuously training the characterization of the picture parameters using user-preferred samples in response to different ambient light conditions.
According to an eighth aspect of the present invention, there is provided a method for adjustment of one or more picture parameters of an image for display on a display device, the method comprising: providing user-adaptive picture parameter determination dependent on the continuous training of the characterization of the picture parameters by making use of user-preferred samples based on different ambient light conditions.
Preferably, the method is user-adaptive for each individual user such that the characterisation of the picture parameters is on an individual user-specific basis.
Preferably, adaptation to a specific user increases with the number of samples provided by a user corresponding to different ambient light levels.
According to a ninth aspect of the present invention, there is provided a method for providing continuous updating of characterization of a particular user's preferences regarding values for one or more picture parameters, using a system for adjusting the values of one or more picture parameters, the method comprising: determining characterisation data based on user-preferred picture values which he/she provides to a system based on different ambient light levels, wherein the user is enabled to provide accurate preferred values within dynamic user-adaptive accessible ranges.
It is to be appreciated that where features or aspects of the invention are set out herein with regard to a method according to the invention, such features may also be provided with regard to an apparatus and vice versa.
Examples of the present invention will now be described in detail with reference to the accompanying drawings, in which:

Figure 1 shows a schematic block diagram of apparatus for adjustment of one or more picture parameters of a display device;
Figure 2 shows a schematic block diagram of a method of adjustment of one or more picture parameters of a display device;
Figure 3 shows a schematic representation of a ranged adjustment block for use in the apparatus of Figure 1;
Figure 4 shows examples of representations of the values of range parameters under various conditions for two different users;
Figure 5 shows a representation of the values of range parameters for one user before and after a training sequence;
Figure 6 shows a schematic representation of an electronic device;
Figure 7 is a block diagram showing in more detail a step from the block diagram of Figure 2; and,
Figure 8 is a graph showing a representation of some sets of User System Parameters for brightness.

Figure 1 shows a schematic representation of apparatus for the automatic adjustment of one or more picture parameters. The apparatus may be implemented by hardware or software but will be described herein as hardware-implemented.
The apparatus 2 comprises an ambient light sensor 4 for detecting the level or intensity of ambient light. Application logic 6 is provided for receiving and processing signals from various other components of the apparatus, to be described below in detail. As with all components of the apparatus, the application logic 6 may be implemented in software or hardware. The application logic 6 is arranged in use to provide control signals for sending picture parameters to a picture controller 8 for varying one or more of the picture parameters (PP) in accordance with a user input or values that are automatically calculated in dependence on ambient light levels and a set of system parameters such as a particular user's system parameters to be described in more detail below.
There are two modes of operation for the apparatus; the manual mode and the automatic mode. In the automatic (first) mode, values "SysPPs" for the picture parameters provided to the picture controller are determined automatically by a picture parameter adjustment system 10 in dependence on ambient light levels and a set of system parameters such as a particular user's system parameter.
In the manual (second) mode, a user manually adjusts one or more of the values for the picture parameters and in so doing the apparatus is arranged both automatically to update the available ranges of the other picture parameters to suit the user's preferences or desires, from which the user can then select a particular value and to update the available range of the picture parameter for which manual adjustment has been made to suit the selected user's preferences or desires.
In the manual mode, the values for the ranges presented to a user are based on the manual value(s) "MPPs" input by the user for the actual parameter being changed and also based on earlier stored sets of system parameters for the user. Thus, the user's particular preferences are taken into account when determining the ranges i.e. the upper and lower limits of the ranges, so that the ranges can be said to be generated dynamically and on a user-adaptive basis. Therefore in a particular embodiment the invention provides an apparatus and a method by which the range of values for picture parameters are made available to a user on a user-defined basis. In other words the ranges made available to a user for selection are tuned to the particular user's preferences.
In practice, it is possible that a user will be unaware of the actual values of the limits of the ranges. An interface is provided such as a slider, with which a user interacts unaware of the actual values for the picture parameters within the range. Therefore even though the actual limits of the ranges may change the slider presented to the user will always look the same to the user.
The actual picture parameter values selected by a user are preferably not stored. Rather, it is preferred that the system only saves characterisation of data, i.e. characterising parameters for the user which are the User System Parameters 22. User System Parameters 22 characterise respective user sensibility. Therefore instead of having to store significant amounts of data, e.g. actual picture parameter values, for each user, by saving user characterisation data in the form of User System Parameters the memory requirement and simplicity of the system can be reduced, and appropriate actual values for the parameters can be determined on-the-fly in accordance with the particular user characterisation.
In another particular embodiment the invention provides an apparatus and a method by which a user can modify only a single picture parameter, e.g. colour, and then the apparatus automatically generates updated dynamic ranges for at least one other of the picture parameters. Thus the apparatus and method are particularly flexible and adaptable as they provide a system by which picture parameters can be tuned accurately on a user-defined basis. User-adaptive dynamic ranges for picture parameters are thus provided.
Different users will have different preferences for the adjustment of picture parameters in response to changes in ambient light conditions. User Inference for picture parameters corresponds to individual determination of the picture parameters based on the characterization of the particular user, which is evaluated by the user himself/herself, dependent of course on the user's viewing perception. In other words, inference for picture parameters is the determination of picture parameters in accordance with changing ambient light conditions, based on selected user characteristics which are dependent on the selected user's eye characteristics.
Range parameter inference is the dynamic determination of range parameters by using a selected user's picture adjustment characteristics, i.e. manually input paremeter changes. This is trained in response to different ambient light conditions by the user and the corresponding picture parameters output as the SysPPs at particular moments based on the selected user picture adjustment characteristics.
Referring again to Figure 1, the picture parameter adjustment system 10 is provided in communication with the ambient light sensor 4 and the application logic 6. As will be explained in detail below, the function of the picture parameter adjustment system 10 is to calculate values for the parameters SysBrightness, SysContrast and SysColour, which represent automatically determined values for the picture parameters brightness, contrast and colour, respectively. In the automatic mode of operation, the values SysBrightness, SysContrast and SysColour are for sending to the picture controller 8 by the application logic 6. In the manual mode of operation, the values SysBrightness, SysContrast and SysColour are used to enable a determination of an available range for the respective picture parameters for presentation to a user to select.
A readable-writeable non-volatile memory 12 is provided in communication with the application logic 6. As will be explained below, the memory 12 is arranged for storage of User System Parameters 22 and is arranged in use to transfer values for the User System Parameters 22 to the application logic 6. A random access memory 14 is provided for temporary storage of User System Parameters so as to avoid the need for repeated accessing of, i.e. reading from or writing to, the non-volatile memory 12 by the application logic 6.
A user-adaptive dynamic range determination or adjustment block 16 is provided in communication with the application logic 6. As will be explained below, the user-adaptive dynamic range determination or adjustment block 16 functions to generate dynamic user-adaptive ranges for picture parameters, for presentation to a user to enable the user to select actual values for the picture parameters. In addition, an accessible range unit 18 is provided in communication with both the application logic 6 and the user-adaptive dynamic range adjustment block 16.
In the example shown, the application logic 6 is arranged in communication with all of the other components of the apparatus 2. The application logic is primarily responsible for enabling communication between different components or blocks of the apparatus and for controlling the values of the picture parameters provided to the picture controller 8.
The memory 12 is arranged, in use, to store default system parameters 20 as well as the User System Parameters 22. As will be explained in detail below, in use, a set of parameters SysPPs is provided to the application logic 6 for provision to the picture controller 8 in automatic mode or the user-adaptive dynamic range determination or adjustment block 16 in manual mode.
A number of inputs 24, 26 and 28 are available for provision to the application logic 6. First, a default/selected user mode input 24 may be provided to the application logic 6. This determines which set of system parameters is read by the application logic 6 and written to the RAM 14. If a default mode is selected, then a set of default system parameters 20 are written to the RAM from the non-volatile memory, via the application logic 6. If a specific user provides some identification to the application logic 6 to inform the application logic 6 that the particular user is engaged with the apparatus, then that specific User System Parameters 22 will be provided to the RAM 14 via the application logic 6 from the non-volatile memory 12, presuming such parameters already exist.
If no such User System Parameters exist, e.g. because a user has not before used the apparatus or registered with it, in an initial iteration or sequence of operation, a set of the default system parameters may be used. However, once a user has trained the apparatus, a specific set of User System Parameters will then be available as that user's User System Parameters 22, for future functioning of the apparatus. Preferably, at any stage a user can reset his User System Parameters to one of the available sets of Default System Parameters
An auto/manual mode input 26 may also be provided to the application logic 6. This serves to determine whether or not the apparatus functions in the automatic or the manual mode, to be described in detail below. Last, a "Train" input 28 may be provided to the application logic, to inform the application logic that a training sequence is to be executed.
Generally, if a user selects automatic mode, the ambient light sensor samples the ambient light level or intensity and provides a corresponding ambient light level signal to the application logic 6. If there is a difference between the measured ambient light intensity and a previous ambient light intensity then the picture parameter adjustment system 10 provides corresponding updated picture parameters SysBrightness, SysContrast and SysColour to the application logic 6. The values SysBrightness, SysContrast and SysColour represent automatically determined values for the picture parameters brightness, contrast and colour for sending to the picture controller 8. The values are user-specific so that for each recognised user corresponding sets of the values SysBrightness, SysContrast and SysColour are automatically calculated.
The picture parameter adjustment system 10 provides corresponding updated picture parameters SysBrightness, SysContrast and SysColour to the application logic 6 not only when there is a difference between the measured ambient light intensity and a previous ambient light intensity, but also when the selected User System Parameters are updated after training.
In contrast, if the manual or "user-adjustment" mode is selected (as it will be if a user seeks manually to adjust one or more of the picture parameters), a user can adjust one or more of the picture parameters to a specific desired level. To enable a user to do this, an interface may be provided in which a user is provided with an accessible range of values for the parameter together with a step size. The accessible range is determined on a user-adaptive dynamic basis in which the limits of the range and preferably the step size within the range are determined using the user's parameters SysBrightness, SysContrast and SysColour and the User System Parameters 22 as inputs.
The user-adaptive dynamic range adjustment block 16 is activated when the manual mode is selected by a user. As with all components of the apparatus, the adjustment block 16 can be implemented in hardware or software. A user selects the manual mode by inputting a manual value for one or more of the picture parameters or when a user enters the manual adjustment menu. The manual values input to the system are referred to herein as MPPs (MBrightness, MContrast and MColour). The automatically generated values are referred to as the SysPPs (SysBrightness, SysContrast and SysColour) and they are generated by the picture parameter adjustment system 10, in dependence on the particular User System Parameters 22 and ambient light levels.
To train the picture parameter adjustment system and determine appropriate values both for the parameters SysBrightness, SysContrast and SysColour specific to a particular user, and the User System Parameters 22 a train signal or input is provided to the application logic 6. This causes the application logic 6 to implement a training algorithm 30 for determining the User System Parameters 22 for the particular user and the parameters SysBrightness, SysContrast and SysColour.
Importantly, once the system has been trained, a set of parameters SysBrightness, SysContrast and SysColour is inferred on a user specific basis for all ambient light conditions. It should be noted that in the manual mode if a user only modifies a single one of the parameters, e.g. colour, then usually the manual values (MPPs) for the other parameters are set equal to the existing corresponding automatic values SysPPs calculated or inferred for that ambient light level. This means that by receiving only a single user input the parameters SysBrightness, SysContrast and SysColour may be determined for all ambient light conditions.
Therefore, a user need only modify a single parameter according to his particular preference or desire and ranges for all the picture parameters of the picture will be updated in a corresponding manner. In a more general example, the system is arranged to update the available ranges of more of the picture parameters than a user actually updates manually, without requiring specific user inputs for each of the ranges.
When a user sends a training signal 28 to the application logic 6, the application logic 6 activates the training algorithm 30 for the User System Parameters that are currently in use. If the user is returning to the system having previously interacted with it, then the parameters being updated will be that specific user's previously-determined and stored User System Parameters. If it is a user's first time with the system then the default system parameters will be used initially and once updated to take into account a user's preferences, the updated parameters will be stored in the non-volatile memory 12 in the section 22 for future use by that specific user. The training algorithm 30 also receives the manually input parameter value MPP.
After training, the apparatus 2 is able to function in different ambient light conditions for that specific user. Training is confirmed or activated when a user confirms his selection of a parameter value or it may be activated when a user exits the adjustment menu or while switching for another picture parameter adjustment or via remote control, for at least one picture parameter. The apparatus 2 updates the user System Parameters 22 for use in determining values for the ranges for the picture parameters for all ambient light conditions for that user.
After training, the apparatus 2 updates the characterisation of the ranges for the particular user. In other words, the User System Parameters are updated in such a way that they characterise a user's preferences.
It is a particular advantage of the apparatus 2 that the apparatus is capable of accurately providing ranges for a particular user including, in a preferred embodiment, the step size for actual parameter selection. As a result, the apparatus ensures that the inputting of involuntary or incorrect picture parameter values is avoided.
The user-adaptive dynamic range adjustment block 16 serves to generate dynamically ranges for a user based in part on the parameters SysBrightness, SysContrast and SysColour received from the application logic 6.
As shown in Figure 1 (and as will be explained below with reference to Figure 7) the value of MPP provided to the application logic 6 from the accessible range unit 18 is referred to as, in a preferred embodiment, the Final MPP value, meaning that it the value of the MPP finally provided to the application after a process of determination and checking described below with reference to Figure 7. That is to say in some cases the value of MPP initially determined by the accessible range unit 18 in response to a user's interaction with a slider, a "Current MPP", may not be appropriate and so will need modification. In such cases the Final MPP provided to the application logic is not the same as the "Current MPP" provided to the user adaptive dynamic range adjustment block 16. Rather, a value referred to as a New MPP is determined and it is the value of New MPP that is provided to the application logic 6 as the Final MPP.
The type of situation in which this may occur is if there is a sudden and dramatic change in ambient light level whilst a user is interacting with the system in the manual adjustment menu. In such cases, as the values SysPP are changing due to the change in ambient light levels, the available ranges may correspondingly change suddenly. Accordingly in order to maintain the user manual input within the newly determined range, a corresponding New MPP may be required and so is accordingly determined. This particular situation will be described in detail below with reference to Figure 7.
Referring both to the apparatus of Figure 1 and the block diagram of Figure 2, the method for determination of picture and range parameters will now be described in detail.
Initially, the ambient light sensor 4 and the application logic 6 determine 32 the ambient light level. Next, at step 33, it is determined whether or not the selected User System Parameters 22 have changed. If there has been a change, which could be for example either as a result of training of a particular user's User System Parameters or because a different user is engaged with the system, then the method proceeds to step 36 at which the new User System Parameters are loaded. This is described in greater detail below but in fact forms the first step in the "inference" operation 35 for determining the values of picture parameters SysBrightness, SysContrast and SysColour.
If there has been no change in the selected User System Parameters, then it is checked whether or not there has been a change in the ambient light level. If it is determined that there has been no change in the ambient light level then the method proceeds to the step 42 of determining the operation mode, i.e. whether or not the apparatus is to function in automatic mode or manual mode. Presuming for now that there has been a change in the ambient light level, the method proceeds from step 34 to step 36 which is the start of what may be referred to as the "inference" operation 35 for determining the values of picture parameters SysBrightness, SysContrast and SysColour.
To start the inference operation 35, the application logic 6 performs a check to see whether a particular user is registered with the system. Presuming a recognised user is actually logged on to the system, the application logic 6 loads selected User System Parameters for that user from the non-volatile memory 12 of the apparatus to the RAM 14 for loading to the picture parameter adjustment system 10 for processing.
If it has been determined that no recognised user is logged on to the system, or if the default mode is selected, a set of default system parameters 20 are loaded to the picture parameters adjustment system 10 in the same manner. The default system parameters 20 are created earlier and loaded to the non-volatile memory 12. The default system parameters 20 have typically been determined using a training algorithm and accurately determined input-output samples which correspond to different ambient light conditions.
As mentioned above, presuming a particular user is logged on to the system, the corresponding User System Parameters are loaded in step 36 to the picture parameter adjustment system 10 by the application logic 6. Initially, when a user first logs on to the system and registers, default system parameters 108 are used for that user. Once that user has been through the method, the updated system parameters are stored for future use as that user's User System Parameters.
Next, at step 38, the inference operation is performed on the selected User System Parameters to produce the system parameters SysBrightness, SysContrast and SysColour, which are based on the ambient light signals and changing levels thereof together with the selected User System Parameters which characterise the particular user's sensibility. Any suitable algorithm may be used so long as it is capable of determining values for the parameters SysBrightness, SysContrast and SysColour representative of the user's preferences.
Next, at step 42, the operating mode of the apparatus 2 is determined. In other words, a check is made as to whether the apparatus is to be operated in manual or automatic mode. Manual mode is used when the user currently engaged with the system provides an input to adjust at least one of the picture parameters. A manual adjustment menu is provided to enable a user manually to interact with the system.
In the automatic mode, if there is an acceptable, i.e. above some threshold level, difference between the current ambient light signal and the previous ambient light signal, as determined at step 32, then at step 64 the adjusted picture parameters which are produced by the picture parameter adjustment system are sent to the picture controller 8 via the application logic 6.
It can be seen then that at step 42, a determination is made as to whether or not a manual adjustment has been made by a user, i.e. whether or not the system is to operate in the manual or automatic mode. If no manual adjustment is made by a user and the system is therefore operating in the automatic mode, at step 62 a determination is made as to whether or not there has been a change in the SysPP values due to a change in ambient light level or a change in the selected User System Parameters. If there is a change in the ambient light level then the corresponding system parameters SysBrightness, SysContrast and SysColour are loaded to the picture controller 8 at step 64. Otherwise, the method returns to step 32 and the ambient light level is measured again.
If it is determined at step 42 that the manual mode is to be used, which occurs when a user provides an input to adjust at least one picture parameter, the system parameters SysBrightness, SysContrast and SysColour are not sent to the picture controller 8. They are calculated or determined in the usual manner as would be done in the automatic mode but instead of being provided to the picture controller 8, they are provided to the user-adaptive dynamic range adjustment block 16. Therefore, at step 44, the user-adaptive dynamic range adjustment block functions to generate "accessible range" limits for the parameter being changed by the user and also to determine the size of "steps" for changing the parameter. A user can then manually change the value of the selected parameter within the limits of the range determined by the user-adaptive dynamic range adjustment block 16.
As explained above, the determination of the limits of the ranges and the step size is made based on the ambient light level, the calculated values SysBrightness, SysContrast and SysColour, the manual user input MPP for whatever parameter is currently being changed or controlled and the pre-stored User System Parameters for that particular user. Thus, the ranges produced and presented to the user are user-adaptive in that they take into account previous expressed user preferences based on the User System Parameters and dynamic in that they are determined based on the SysPP values which change in part in dependence on ambient light levels. Adaptation of User System Parameters is continuous as training serves to continually update the particular User System Parameters.
The manual inputs MPPs are not considered as direct inputs for use in range determination, but rather they have an indirect effect due to the training process after which the selected User System Parameters are updated.
The ranges are user-adaptive in that selected User System Parameters which characterise a particular user are continuously updated via the preferred picture parameter input e.g. training by the particular user, and an adaptation to the particular user is therefore achieved.
The ranges generated are dynamic in that they are determined based in part on the SysPP values which are updated in part in response to variations in ambient light conditions, this causing a dynamic change in the limits of the available ranges for the picture parameters.
Next, at steps 46 and 48, it is determined whether or not a manual parameter MPP has been changed by the user. If no change has been made then the method progresses along route 50 back to step 32 at which the ambient light value is again determined and the method can then be repeated.
If a value for one or more of the picture parameters has been manually changed by a user, then first, at step 54 the manually-adjusted picture parameter MPP, or preferably the value Final MPP, is loaded to the picture controller 8 to change or control the picture parameter in question. The user can then observe the effect of the manual input on the display and can further adjust the value of the parameter within the constraints of the determined accessible dynamic range based on the user's sensibility.
It is preferred that even when only a single one of the picture parameters is manually adjusted by a user that corresponding changes, based on inference i.e. the factors mentioned above including calculated or determined values for SysBrightness, SysContrast and SysColour, and the User System Parameters etc, are made to the limits of the ranges of values of at least one other and preferably all of the other picture parameters. Therefore, the method and apparatus provides a simple and robust system by which a user may accurately vary the picture quality to achieve an improvement in the image quality.
The selected User System Parameters are updated (trained) only if a training command or instruction is provided by a user confirming or accepting his/her tuned adjustment for at least one of the picture parameters, i.e. a preferred setting. Alternatively, the training command may be received if the user exits the adjustment menu or switches to control or vary another picture parameter or via Remote Control. Accordingly, if a selected user manually tunes a picture parameter setting but does not provide a training command by confirmation, then ranges for the other picture parameters may only be updated due to a change in ambient light conditions causing a corresponding variation in the values SysPP.
Merely tuning of the user for a picture parameter setting over the slider or interface, e.g. manual adjustment, does not automatically provide a corresponding change in the selected User System Parameters, since a training command has not been given. However, when the user provides a confirmation for his/her tuning e.g. preferred setting, then a training algorithm is activated and the User System Parameters will be updated.
At step 56, when a selected user tunes at least one picture parameter, a training command may automatically be sent to the application logic 6. This is used to ensure that by manually changing one of the picture parameters, accessible ranges provided by the range adjustment block 16 are determined. After training, the User System Parameters are updated for the particular user and since User System Parameters are input to the picture parameter adjustment system 10, new SysPPs are also produced. So, not only does a user input have the effect of potentially causing a variation in the accessible ranges, but values for SysPPs also change. The training command sent to the application logic 6 may also be used for evaluation of the picture parameter adjustment system 10, i.e. update of selected User System Parameters in accordance with the training inputs (preferred settings) provided by the user.
At steps 56 to 60 it is determined whether a training command has been issued and if it has then the corresponding training is performed by the training algorithm 30 operating within the picture parameter adjustment system 10. As already mentioned, a user may send a train command by choosing manually to adjust one of the picture parameters or simply by exiting the adjustment menu. The training command may be sent to the application logic 6 using any suitable means. An example includes remote control.
After training, at step 60, the updated selected system parameters are overwritten to the non-volatile memory 12 and the RAM 14. Next, the method returns to step 32 where the ambient light signal is read again and the whole process can be repeated. The process of picture parameters adjustments preferably starts when a video signal is available on the display.
It will be appreciated, referring to Figure 1 that the values SysBrightness, SysContrast and SysColour are provided to the user-adaptive dynamic range adjustment block 16 and these values are used to determined range adjustments dynamically and on a user-adaptive basis. Thus, the user-adaptive dynamic range adjustment block 16 is capable of enabling a user to tune and train accurately the picture parameters of a particular image.
It is particularly desirable that by seeking to modify only one picture parameter, available ranges for other of the picture parameters will be automatically updated based on an inference of a user's preferences. A user does of course have the ability to modify independently each of the values for the other parameters not initially varied, but the accessible ranges for the other picture parameters are determined at least in part by the change in the first picture parameter made by a user.
In one embodiment, the method of adjusting a picture parameter is particularly user-friendly in that values of system parameters previously determined in respect of a user are stored in memory of the system. Therefore, on identification of a particular user, e.g. by use of an identification key such as a password or a user name, the system is able to present to a user immediately the appropriate ranges for selection of values for the picture parameters for the current level of ambient light.
Alternatively the system can simply provide the values of the picture parameters selected by that user to the picture controller, based on the currently measured ambient light level. Therefore, the method and apparatus is capable of providing user-adaptive dynamic range determination to enable a user to accurately tune and train the picture parameters of an image as desired.
Figure 3 shows a schematic representation of the user-adaptive dynamic range adjustment block 16 of Figure 1. The adjustment block 16 receives as inputs both the values SysBrightness, SysContrast and SysColour determined automatically in dependence on the ambient light level and the selected User System Parameters 22 for the particular user. In response to these inputs, and the value of the parameter being manually changed by a user, the user-adaptive dynamic range adjustment block 16 calculates user-adaptive ranges for each of the picture parameters brightness, contrast and colour, together with appropriate step sizes.
The determined user-adaptive dynamic ranges may then be provided to the accessible range unit 18 in Figure 1 to enable a user optionally to vary other of the picture parameters in addition to the originally adjusted parameter. This will be within the constraints set by the dynamically calculated ranges for the other picture parameters.
Thus, the system provides a user-adaptive method and apparatus for enabling a user to tune the values of picture parameters to particular desired values. The inputs to the dynamic range adjustment block 16 include both the automatically calculated parameters SysBrightness, SysContrast and SysColour and also the selected User System Parameters retrieved from the RAM 14 or, in the first instance, the memory 22. Therefore, the ranges are determined based not only on the ambient light levels as has been done previously, e.g. in US-A-6,947,017 , but also based on User System Parameters or on a set of trained default system parameters as explained above. Additionally, US-A-6,947,017 provides only a fixed characterization for ranges, and it does not disclose user-adaptive dynamic ranges for picture parameters.
Figure 7, shows a block diagram showing in more details the constituent sub-steps for step 44 from the method of Figure 2. In step 44 the user-adaptive dynamic range adjustment block generates "accessible range" limits for the parameter being changed by the user and also preferably determines appropriate sizes of "steps" for changing the parameter.
In some situations, it is possible that the ambient light level changes significantly whilst a particular user is operating in the manual adjustment menu. In such cases the user manual input may be out of range. Accordingly, in order to keep the user manual input within the range, a corresponding New MPP is determined.
With reference to Figure 7 and Figure 3, at step 44a the inputs to the user adaptive dynamic range adjustment unit are read. These inputs, as shown in Figures 1 and 3, comprise the parameters SysBrigtness, SysColour and SysContrast, together with the selected User System Parameters 22. At step 44b the value of Current MPP is read, this being the value currently being input by a user via a selection optionally using a slider as described below with reference to Figures 4 and 5.
At step 44c a comparison is made to determine whether or not the inputs of SysBrigtness, SysColour and SysContrast and the User System parameters are the same as the previously read values for the parameters. If it is determined that the values of all these parameters have not changed then the Current MPP value is set as the Final MPP value for providing to the application logic 6 as shown in Figure 1. If there is a difference between any of the corresponding previous and current parameters, then as described above the adjustment block 16 determines new range parameters and step sizes at step 44e.
Next at step 44f a check is made as to whether or not the Current MPP value is within the newly determined range. It may be the case that it is not if, for example, there has been a sudden and significant change in the ambient light level. If it happens that the value of Current MPP is outside the available determined range, then a new MPP value is determined referred to as New MPP. This value of New MPP is then set as the Final MPP at step 44i for provision to the application logic 6 as shown in Figure 1.
As one example, consider a situation in which a user enters into the manual adjustment menu. At that particular point in time the available brightness range might be between the values of 100 and 150, and the actual setting at that time may be, say, 120. Of course the user will preferably not see the actual value of brightness or indeed the range limits, but rather see only the relative position of the slider on the available range. In this situation, the Current MPP is 120, although the user does not necessarily know this. Suppose the user then seeks to increase the brightness to a level of 130. If the inputs to the range adjustment block 16 remain the same, i.e. the values of the parameters SysPPs and the User System Parameters, then a new range will not be determined and the value of Final MPP provided to the application logic 6 will be equal to the value of Current MPP.
However, suppose now that a new range is determined from 130 to 180, because, say, there has been a significant change in ambient light levels causing a corresponding change in the values of the parameters SysPPs. If the slider was pointing to a value of 120 in the now old range, then since 120 is outside the newly determined range for brightness, a new value for the brightness MPP, referred to generally as New MPP must be determined and this must then be provided to the application logic as the Final MPP. It can be seen then that in some cases Final MPP is set to the value of Current MPP, but in some cases when a dynamic change in range has created the situation in which the value of Current MPP is outside the available range, then a new value for MPP, referred to as New MPP must be used instead and used as the value of Final MPP. Thus with this preferred arrangement the system is robust and able to adapt to dramatic or significant changes in ambient light levels.
Referring to Figures 4 and 5, examples of the values of the range parameters under various considerations such as the ambient light, selected user, training etc. are shown, that enable a user to vary manually the picture parameter values. Referring first to Figure 4, the values for two users, user A and user B are shown at two ambient light levels, 50 and 150. At ambient light level 50, the values for SysBrightness, SysContrast and SysColour for user A are 138, 188 and 118, respectively. As shown in Figure 5, in the "Before Training" column, a user has provided an input to indicate that an increase in the contrast parameter is required of 10 units, to 198. Typically a user will not be required to provide any sort of numerical input. Rather, an intuitive relative input is provide by a user by varying the position of the slider.
In other words, the manual parameter MContrast has now been set at 198. Therefore, in the "After Training" column, it can be seen that the value for SysContrast is now set at 198 equal to the value entered for MContrast by the user. In addition, although the user has made no manual adjustments to the values or settings for brightness and colour, the brightness range, after the training has changed from 122 to 188 which it is was before training, to 130 to 170. The range for the colour parameter has changed from 80 to 140 which it is was before training to 92 to 130. Thus, by manually modifying a single parameter (contrast in this case), a change in the limits of the ranges of the other parameters (brightness and colour) is automatically generated. The available range for contrast has also changed.
In the examples shown in Figure 4, in accordance with varying ambient light conditions and selected user system parameters, there are different accessible ranges and step sizes for providing to a selected user to enable tuning of a desired picture parameter which are then used for picture adjustment system training. For example, when the ambient light sensor senses a value of 50, the system will produce SysBrightness equals 138, SysContrast equals 188 and SysColour equals 118 for user A, whereas for user B the respective values will be 149, 210 and 148. Under the same light conditions, the range adjustment system will therefore provide different ranges to the users A and B based on user sensibility and inference.
Also, when ambient light conditions change (right hand column of Figure 4) to 150, the values of the parameters SysBrightness, SysContrast and SysColour will be different. The parameters x, y and z are calculated in order to determine the new values for the manual picture parameters in response to user input. This is because typically a user will not enter an actual value when acting to change a picture parameter but rather will provide an input to decrease (or increase) the parameter in question.
Referring to Figure 5, as explained above, the values for the parameters SysBrightness, SysContrast and SysColour and the ambient light value of 50 are 133, 188 and 118 respectively. When a user enters an adjustment in at least one of the picture parameters the adjusted value is set as the next SysPP value. In other words, the manualPP value is set equal to SysPP value for the next iteration. See, the right hand column of Figure 5 where it can be seen that SysContrast now is set at 198 which was the value that it was changed to from the original value of 188 in the left hand column.
After a training command has been sent, the range adjustment is implemented for all the picture parameters even though in fact the user only sought to modify the contrast level of the picture. Presuming there is no change in ambient light levels the values for the other picture parameters SysBrightness and SysColor remain the same even though the available ranges for these values have now changed. The user can of course seek to modify the values for brightness and colour manually.
The values x, y and z are determined as the difference between the system picture parameters (SysPPs) and the manually entered system parameter in any iteration of the method. Thus, the limits set to the ranges of values can be quantified as follows:

a, b, x, SBrightness for Brightness
c, d, y, SContrast for Contrast
e, f, z, SColour for Colour

a;

Accessible Brightness Maximum value

b;

Accessible Brightness Minimum value

x;

x = SysBrightness - ManualBrightness SBrightness; "increasing and decreasing" step information for Brightness

c;

Accessible Contrast Maximum value

d;

Accessible Contrast Minimum value

y;

y = SysContrast - ManualContrast

SContrast;

"increasing decreasing" step information for Contrast

(See comment below)

e;

Accessible Colour Maximum value

f;

Accessible Colour Minimum value

z;

z = SysColour - ManualColour

SColour;

"increasing decreasing" step information for Colour

In one particular embodiment, an electronic device such as a television is provided including a display device. The electronic device is provided with apparatus for enabling a user to vary the values of one or more picture parameters. Examples of suitable display devices for use in such electronic devise include but are not limited to a computer monitor, an electronic notebook, a personal digital assistant, a projection television, a plasma television, a cathode ray tube television, a liquid crystal display television or indeed any other suitable type of image or video display device. Figure 6 shows a schematic representation of such a device. Many components that may be included are not shown and indeed the figure is only provided to give a general indication of the likely basic components of such a device.
The device 66, comprises a display device 68 coupled to some means for providing an image signal to the display device 66. In the schematic example shown the means for providing an image signal comprises a processor 70 in communication with an image parameter adjustment apparatus 72 which may be like that shown in Figure 1.
Figure 8 shows a schematic representation of User System Parameters and how they are determined or trained for a particular user. In the example shown the User System Parameters are shown in graph form defining a relationship between brightness (of a display) and ambient light. For each of User A and User B shown, it can be seen that as the intensity of ambient light increases the level of the brightness parameter increases too. Also shown is a relationship defined by a set of default system parameters which, in this case, is a straight line, i.e. there is a linear relationship between the level of ambient light and the brightness image.
By referring to Figure 8, it can be seen that the more samples a user provides the more the User System Parameters can be trained to satisfy the particular user's preferences across all ambient light levels. Referring to Figure 8, assuming that the ambient light level is "x", a function is assumed between ambient light and brightness in a determined ambient light range of ALS1 < x < ALS2. $Fdefault (x) = D 1 x + D 2,$
$FuserA (x) = A 1 x + A 2,$
$FuserB (x) = B 1 x + B 2,$
$FUserC (x) = C 1 x + C 2$

D1, D2 Default system parameters for Brightness
A1, A2 User A system parameters for Brightness
B1, B2 User B system parameters for Brightness
C1, C2 User C system parameters for Brightness

When a user trains the system by providing a manual input which will correspond to a preferred brightness in a ambient light condition in a determined available ambient light range, the parameters A1 and A2 are updated based on the indicated desired brightness within the determined ambient light range. In the example described and shown herein, a linear relationship is presumed between desired brightness level and ambient light level. This provides for simplicity in terms of computational processes and resources. Other possible relationships may also be used, i.e. non-linear relationships.
It can be seen that the method and apparatus provides a simple yet robust method by which a user can accurately train a picture parameter adjustment system and also can enable individual users to tune pictures in accordance with their own specific desires. In other words, the apparatus and method provide a user-adaptive dynamic range picture adjustment methodology.
Embodiments of the present invention have been described with particular reference to the examples illustrated. However, it will be appreciated that variations and modifications may be made to the examples described within the scope of the present invention.

Claims

A method of adjusting a picture parameter for displaying an image on a display device, the method comprising:
storing for each user parameters to characterise user preference for the values for at least one picture parameter;

on identification of a particular user, determining at least one range for presentation to the user to enable a user selection of the value for one or more of the at least one picture parameter in dependence on the stored user characterisation.
A method according to claim 1, comprising, in dependence on the user's selection, training the characterisation of the user.
A method according to claim 2, wherein upon training of the characterisation of the user, the one or more other ranges are updated based on the trained characterisation.
A method according to any of claims 1 to 3, wherein the one or more picture parameters include colour, brightness, contrast, hue and separate RGB saturation.
A method according to any of claims 1 to 4, the method being for providing user-adaptive range determination for the values of one or more picture parameters for display on a display device, the method comprising:
continuously training the characterization of the picture parameters using user-preferred samples in response to different ambient light conditions.
A method according to claim 5, in which the method is user-adaptive for each individual user such that the characterisation of the picture parameters is on an individual user-specific basis.
A method according to claim 5 or 6, in which adaptation to a specific user increases with the number of samples corresponding to different ambient light levels provided by a user.
A method according to any of claims 1 to 7, comprising:
providing user-adaptive picture parameter determination dependent on the continuous training of the characterization of the picture parameters by making use of user-preferred samples based on different ambient light conditions.
A method according to claim 8, in which the method is user-adaptive for each individual user such that the characterisation of the picture parameters is on an individual user-specific basis.
A method according to claim 7 or 8, in which adaptation to a specific user increases with the number of samples provided by a user corresponding to different ambient light levels.
A method for adjustment of one or more picture parameters of an image for display on a display device, the method comprising:
either, in response to receipt of a user preference for the value of a first picture parameter of the image automatically determining and/or adjusting the available range of at least one picture parameter of the image;

or, upon identification of a user, automatically updating one or more picture parameters in dependence on characterising parameters for that identified user and ambient light levels.
A method according to claim 11, comprising, when a user preference for the value of a first picture parameter is provided, presenting the available range of the at least one picture parameter to the user for selection of a value of the at least one picture parameter.
A method according to claim 11 or 12, wherein the first or other picture parameters comprise one or more of colour, brightness, contrast, hue and separate RGB saturation of an image for display on the device.
A method according to any of claims 11 to 13, wherein in a first mode of operation, upon loading of a current user's characterising parameters and detection of a corresponding ambient light level, a value for each of one or more picture parameters is automatically provided to the display device for image display in accordance with the said value or values.
A method according to claim 14, wherein in a first iteration of the first mode of operation, the or each of the values automatically provided is or are derived from at least one default system parameter dependent on ambient light levels.
A method according to claim 14 or 15, wherein in a second mode of operation, upon receipt of a user indication for the value of the first picture parameter, the available ranges for one or more other picture parameters are determined in dependence on the or each of system-calculated values for the picture parameters which are provided automatically.
A method according to claim 16, in which the available ranges for the one or more other picture parameters are determined in dependence in part on the selected characterising parameters.
A method according to claim 6, wherein the user indication of the value for the first picture parameter is used to determine a desired user preferred value of the first parameter for use in future iterations of the method.
A method for providing continuous updating of characterization of a particular user's preferences regarding values for one or more picture parameters, using a system for adjusting the values of one or more picture parameters, the method comprising:
determining characterisation data based on user-preferred picture values which he/she provides to a system based on different ambient light levels, wherein the user is enabled to provide accurate preferred values within dynamic user-adaptive accessible ranges.
A method according to claim 19, in which the user-preferred picture values are not stored by the system.
A method according to claim 19 or 20, in which the characterisation is updated when a training command is provided by a user engaged with the system.
A method according to any of claims 19 to 21, in which the training command, is provided by one or more of Remote Control interaction, menu interaction via activation of an item in a picture parameter adjustment menu, switching to adjust another picture parameter or exiting the picture adjustment menu.
Apparatus for adjusting one or more picture parameters, the apparatus comprising:
a processor for receiving user inputs and a user identifier;

memory for storing characterising parameters previously determined for particular users in dependence on the user; and

a range determination unit for providing ranges of a particular user for display in dependence on the user identifier.
Apparatus according to claim 23, wherein the memory is provided as a non-volatile memory.
Apparatus according to claim 23 or 24, comprising an output generator, arranged upon selection of at least one value for a picture parameter to output the parameter to a picture controller.
Apparatus according to any of claims 23 to 25, comprising a picture controller for receiving the picture parameter value or values and applying the values to an image on a display.
Apparatus according to any of claims 23 to 26, comprising a display device for displaying images.
Apparatus according to any of claims 23 to 27, wherein the memory stores a number or predetermined sets of default system parameters such that when a new user first uses the apparatus one or more of the predetermined sets of default system parameters may be trained by the user to generate user-specific User System Parameters.
Apparatus according to claim 28, arranged upon first use by a new user to store user-characterising User System Parameters and to use these to determine values for ranges of the picture parameters for future use by the said user.
Apparatus according to any of claims 23 to 29, arranged to operate in either an automatic mode or a manual mode, wherein,
in the automatic mode, system calculated values for picture parameters are automatically provided to a picture controller in dependence on the ambient light level and the characterising parameters of the identified user; and
wherein in the manual mode, the apparatus is arranged to receive a user input and, in dependence on the user input, the system-calculated values for the picture parameters and user-characterising User System Parameters, to determine available ranges for at least one other picture parameter.
Apparatus according to claim 29 or 30, wherein the picture controller is arranged to provide values for picture parameters to a display device for displaying images using the said picture parameter values.
Apparatus for adjustment of one or more picture parameters of an image for display on a display device, the apparatus being arranged in response to receipt of a user preference for the value of a first picture parameter of the image automatically and dynamically in response to variation in ambient light level to determine and/or adjust the available range of at least one picture parameter of the image.
Apparatus according to claim 32, wherein upon determination or adjustment of the available range of the at least one picture parameter of the image, the apparatus is arranged to display the determined or adjusted ranges to the user to enable the user to select an actual value or change in value for the at least one picture parameter of the image and/or to train the apparatus for the user.
Apparatus according to any of claims 30 to 33, comprising a range determiner to receive the user preference and make the required determinations or adjustments to the available range of the at least one other picture parameter of the image.
Apparatus according to claim 34, comprising a picture controller to receive an input from the processor indicative of the changes in the picture parameters to be applied to a displayed image.
An electronic display device for displaying images, the electronic display device comprising a display;
a processor for providing image signals to cause the display of images on the display device; and,
apparatus for adjusting one or more picture parameters of images for display or when displayed on the device, the apparatus being apparatus according to any of claims 23 to 35.
Apparatus for adjustment of one or more picture parameters of an image for display on a display device, the apparatus comprising:
an ambient light sensor for determining the level of ambient light;

memory for storing user system parameters to characterise a user's sensibilities and preferences regarding picture parameters in dependence on ambient light levels;

a picture parameter adjustment unit for automatically determining the required value for one or more picture parameters in dependence on the ambient light level and the user system parameters.
Apparatus according to claim 37, comprising a range determination unit coupled to the picture parameter adjustment unit, the rage determination unit arranged, in one mode of operation of the apparatus, to determine appropriate ranges for one or more picture parameters for presentation to a user for selection of an actual value, wherein the appropriate ranges are determined in dependence on the user system parameters and the automatically determined value for one or more picture parameters in dependence on the ambient light level.
Apparatus according to claim 38, the apparatus being arranged upon receipt of a user input indicative of a selection of an actual value for one or more picture parameters, to update the user system parameters accordingly.
Apparatus according to any of claims 37 to 39, comprising a picture controller to receive values for picture parameters and update an image displayed on a corresponding display device in accordance with the received values.
Apparatus according to claim 40, comprising a display device for displaying an image.