Summary of the invention
The technical issues that need to address of the present invention are, how a kind of Mobile phone backlight control method is provided, and can, under the prerequisite that does not affect the display screen effect, reduce to greatest extent the mobile phone backlight power consumption.
Technical matters of the present invention solves like this: build a kind of Mobile phone backlight control method, comprise the following steps:
Detect current environmental light brightness by the sensor on incoming call event or actuation of keys Event triggered mobile phone or camera;
According to described environmental light brightness size adjustment screen luminance of mobile phone value: environmental light brightness is larger, the screen luminance of mobile phone value is higher;
Adjust mobile phone screen according to described environmental light brightness size and show image: environmental light brightness is larger, adjusted value is higher, and described adjusted value comprises to the Enhancement contrast value of low-light level pixel or to the contrast reduction value of high brightness pixel.
According to control method provided by the invention, except incoming call event or actuation of keys event, also include, but are not limited to: by sensor or the camera that comes short message event to trigger on mobile phone, detect current environmental light brightness.
According to control method provided by the invention, also comprise the processing backlight to cell phone keyboard, specifically include, but are not limited to following two kinds of schemes:
(i) change the cell phone keyboard backlight brightness values according to described environmental light brightness size: environmental light brightness is larger, the cell phone keyboard backlight brightness values is lower;
Wherein: described cell phone keyboard backlight brightness values includes, but are not limited to adopt the dutycycle of the pulse-length modulation of corresponding mobile phone CPU output to be controlled;
(ii) light cell phone keyboard according to described environmental light brightness size lower than the keyboard back light thresholding backlight, otherwise the cell phone keyboard that goes out is backlight, described cell phone keyboard thresholding backlight is the steady state value that the user can set in advance.
According to control method provided by the invention, described display backlight is regulated the function that includes, but are not limited to adopt corresponding following two kinds of situations:
(i) approximately linear function
C=1/(2-M
(B?-1))+kA;
(ii) exponential form function
C=1/(2-M
(B-kA-1)),
Wherein M is the horizontal ordinate of grey scale transformation point, and C is the multiple of display backlight brightness with respect to original intensity, and A is intensity information, and B is mode of operation, and k is the light intensity susceptibility of display backlight.
According to control method provided by the invention, described mobile phone screen shows that Image Adjusting includes, but are not limited to adopt the function of corresponding following two kinds of situations:
(i) only surround lighting is regulated
Y?=?-X
(A+1)?+?2X,
(ii) containing GTG, process
Y?=?-X
(A+2)+?2X;
Wherein X is certain the picture element grey scale normalization value before conversion, and Y is certain the picture element grey scale normalization value after conversion, and A is intensity information.
According to control method provided by the invention, it is as follows that the present invention solves the logic module that its technical matters adopts: illuminant module, processor module, the data transformation submodule, display screen, display backlight control module, the display backlight module, keyboard back light control module, keyboard back light module.
In such scheme, the backlight control flow process is as follows:
1. at first processor module is judged user's setting:
When backlight being set to " only surround lighting brightness adjusting function ", processor is controlled the data transformation submodule view data is not carried out to the GTG processing, directly is transferred to display screen.Now contain when operation: incoming call, receive note, there is button to press, when display screen is lighted and is waited, the triggering illuminant module, and gather light intensity data to the frequency of 25Hz from illuminant module with 5Hz, then enter step 2.
When backlight being set to " closed adjusting backlight " or when " only reducing picture quality ", processor is locked as intermediate value by light intensity data, to cancel its regulating effect.Now contain when operation: incoming call, receive note, there is button to press, when display screen is lighted etc., do not trigger illuminant module, then enter step 2.
When backlight being set to " full-automatic adjusting backlight ", when operation contains: incoming call, receive note, there is button to press, display screen is lighted while waiting, the triggering illuminant module, and gather light intensity data to the frequency of 25Hz from illuminant module with 5Hz, then enter step 2.
2. when transmitting display data, processor is processed respectively light intensity signal, then be transferred to respectively data transformation submodule and keyboard back light control module, and then send respectively corresponding switch control data to display backlight control module and keyboard back light control module.The setting of analysis user, for " closing adjusting backlight ", " only surround lighting brightness adjusting function ", and " only reducing picture quality ", " full-automatic adjusting backlight " 4 kinds of mode of operations, the working method of control data transformation submodule, enter step 3.
3. the data transformation submodule, to showing that data are converted, is then exported to display screen and is shown, the while generated data also is transferred to the display backlight control module.Enter step 4.
4. display backlight control module and keyboard back light control module are processed the data that receive, and control respectively cut-offfing with bright dark of display backlight module and keyboard back light module.
In such scheme, the control law of display screen is as follows:
When receiving the demonstration data, the GTG contrast that shows data is carried out to certain raising, then with the light intensity data of receiving, the GTG contrast is once adjusted again.The adjustment mode is: if light is stronger, light intensity data is larger, contrast is turned down; If light a little less than, light intensity data is less, contrast is heightened.
In such scheme, the rule of display backlight control module is as follows:
Receive data C as the brightness reference, the C value is larger, backlight brighter, and the C value is less, and backlight darker, vice versa.The data that CPU transmits are only controlled backlight whether lighting.
In such scheme, the rule of keyboard back light control module is as follows:
The bright dark and switch that the Data Control that CPU transmits is backlight.Can be the PWM waveshape, dutycycle is higher, and keyboard back light is brighter; Dutycycle is lower, and keyboard back light is lower, and vice versa.
Mobile phone backlight control method provided by the invention, integrated environment photoinduction and image gray-scale level are processed, amplitude peak reduces backlight power consumption, further surround lighting, display screen, display backlight and keyboard back light are designed to a system, adopt multichannel and efficient regulative mode dynamically to control system, thereby do not affect display effect, raising user's experience in the reduction backlight power consumption.
Embodiment
At first, total system of the present invention is described:
As Fig. 1, mobile phone backlight control system of the present invention comprises the following functions module:
(i) processor
Operation and setting according to the user, read light intensity data with certain frequency from sensor devices in needs, then in conjunction with backlight whether needs of user's Operations Analyst display screen and keyboard, open, generate multichannel data and control signal after overall treatment, be transferred to respectively the display screen driver module, the display backlight control module, the keyboard back light control module.
(ii) display screen driver module
In the display screen driver module, the data transformation submodule, according to the data A received, carries out a kind of conversion process to the GTG that shows data, afterwards the display data transmissions after conversion is shown to display screen.While generated data C also passes to the display backlight control module.
(iii) display backlight control module
The data that transmit according to CPU and data transformation submodule, control the display backlight module after processing and adjust display backlight brightness;
Receive data C as the brightness reference, the C value is larger, backlight brighter, and the C value is less, and backlight darker, vice versa.The data that CPU transmits are only controlled backlight whether lighting.
(iv) keyboard back light control module
The data that transmit according to CPU and control signal, the supervisory keyboard backlight module is adjusted keyboard back light brightness.
The second, control program of the present invention is described:
(i) the control program of illuminant module of the present invention as shown in Figure 2, comprises following steps:
Does the S201:CPU instruction arrive? judge that whether CPU is from the illuminant module reading out data, if receive the instruction of reading carry out S202, otherwise continue to carry out S201;
S202: gather surround lighting and generate light intensity data, sending it to processor.Then carry out S201.
(ii) the master control program of CPU of the present invention as shown in Figure 3, comprises following steps:
S301: judge whether to read the illuminant module light intensity data, need to read and carry out S302, otherwise carry out S301-3;
S301-3: the locking light intensity data is in moderate value.Its effect is to make light intensity data ineffective treatment in the processing of back, by data A is locked as to 0, make its in the back the impact in computing can ignore.
S302: the frequency with 5Hz-25Hz reads light intensity data from illuminant module.This frequency is adjustable,, when underfrequency may make image change the ladder sense excessively strong, frequency is too high can reduce work efficiency, take 5 Hz-25Hz for reasonable.
S303: the light intensity data obtained is processed respectively.Processing procedure need to be current to the user operation, state, and the information such as arrange of mobile phone is analyzed, and then in conjunction with light intensity data, for the data transformation submodule, the display backlight control module, the keyboard back light control module calculates respectively corresponding data.
S304: the data A after processing is transferred to data processing module.Data A is obtained by the light intensity data linear transformation, and light intensity is lower, and this value is lower, and light intensity is larger, and this value is larger.This value will be to showing that data exert an influence at the transformation curve of data transformation submodule.
S305: the switch control data of display screen is transferred to the display backlight control module.
S306: the backlight brightness data of keyboard and switch control data are transferred to the keyboard back light control module.It is backlight that the environmental light brightness size is lighted cell phone keyboard lower than the keyboard back light thresholding, otherwise the cell phone keyboard that goes out is backlight, and described cell phone keyboard thresholding backlight is the steady state value that the user can set in advance.Under condition in the environmental light brightness size lower than the keyboard back light thresholding, environmental light brightness is larger, and backlight illumination is less, and environmental light brightness is lower, and backlight illumination is higher.
S307: by display data transmissions to data processing module and process other tasks.
S308: whether need to carry out light intensity sampling next time.If need to would carry out S301, otherwise carry out S307.
(iii) data transformation submodule program in display screen driver module of the present invention as shown in Figure 4, comprises following steps:
S401: show that data arrive? if receive the demonstration data, carry out S402, otherwise carry out S401;
S402: in conjunction with data A, to showing data, carry out grey scale transformation.The flow process of conversion is as follows:
According to its normalized pixel brightness histogram of the demonstration data statistics received.The minimum brightness of pixel is 0, and maximum brightness is 1.According to pixel brightness, order is from low to high arranged pixel, calculates the brightness maximal value in front 90% picture element, is designated as M, and its implication is the horizontal ordinate of grey scale transformation point.That in calculating, uses 90% can regulate;
Then according to the data A read, determine transformation curve.Transformation curve has various ways, and what the present invention adopted is index functional form transformation curve, and form is: Y=-X
(A+B)+ 2X, wherein X is certain front picture element grey scale normalization value of conversion, Y is certain the picture element grey scale normalization value after converting.This form curve is through (0,0), (1,1) point, meet basic normalization grey scale transformation condition, this curve is index curve simultaneously, is to realize one of important function form that dynamic backlight is regulated, and in formula, the A value is the data A that CPU transmits, implication is intensity information, it is worth between (q, q), 0<q<0.5.Q increases, and A increases the impact of grey scale transformation; Q reduces, and A reduces the impact of grey scale transformation.The concrete value of q needs debugging, and what it was expressed is the strength of adjustment of light intensity to this index grey scale transformation curve.When ambient light intensity increases, the A value increases, and when ambient light intensity reduces, the A value reduces.If light sensation is not regulated and opened, when the user is set to " closing adjusting backlight " or " only reducing picture quality ", the A value is locked as 0.B value implication is mode of operation, and when the user is set to " only reducing picture quality " or " full-automatic adjusting backlight ", the B value is 2.Reason is when A=0, and no light perception is regulated, and grey scale transformation is now only arranged, and the grey scale transformation curve needs the form of quadratic function, therefore the B value is set as 2.When the user is set to " closing adjusting backlight " or " only surround lighting brightness adjusting function ", the B value is 1, now shows that the grey scale transformation curve of data only is subject to ambient light effects;
After determining transformation curve, need to determine change point.Make X=M, substitution curve Y=-X
(A+B)In+2X, the Y value obtained is set as N.Obtain change point (M, N);
Then determine final GTG mapping curve.Straight line connects (0,0) and (M, N) and obtains curve a, and straight line connects (M, N), and (1,1) obtains curve b.Curve a, b is exactly final GTG mapping curve;
Finally will carry out grey scale transformation to showing data.Be less than the pixel of M for the X value, by curve, a is converted into Y; Be greater than the pixel of M for the X value, by curve, b is converted into Y.The Y value obtained according to this kind of method is approximate value;
After it should be noted that each time the GTG mapping curve is determined, can in the demonstration data of next a frame or multiframe, use, this can fix also can be according to user's demand setting.
S403: the demonstration data after processing are exported to display screen and shown.
S404: C is to the display backlight control module for the output data.Then carry out S401;
The implication of C is the multiple of display backlight brightness with respect to original intensity.Consider that operand is larger, adjusting parameter output data C backlight does not adopt the exponent arithmetic form in the present invention, and formula of index is C=1/ (2-M
(B-kA-1)), but adopt linear-apporximation to calculate.Linearity Formula: C=1/ (2-M
(B-1))+kA, wherein 1/ (2-M
(B-1)) be partly the brightness regulation of making in order to coordinate the GTG adjustment that shows data, kA coordinates ambient light intensity to change and the linear regulation amount of introducing, 0<k<1 wherein, implication is the light intensity susceptibility of display backlight, means the reaction sensitivity that ambient light intensity is changed backlight.Its value is larger, and backlight illumination is subject to ambient light effects larger; Its value is less, and backlight illumination is subject to ambient light effects less.This value can be set in user interface, light sensation can be provided more flexibly and control.Compare exponential transform simultaneously, adopt linear function to also have a benefit, there is larger brightness regulation scope, backlightly under dark surrounds can reach darker degree; Under the high light environment, backlightly can significantly promote brightness, enough brightness supports are provided.
(iv) the control program of display backlight control module of the present invention as shown in Figure 5, comprises following steps:
Does S501: the switch control command arrive or data C arrives? if have order or data to arrive, carry out S502, otherwise carry out S501;
S502: by controlling the display backlight module, regulate display backlight brightness.Then carry out S501.
(v) the control program of keyboard back light control module of the present invention as shown in Figure 6, comprises following steps:
Does S601: the switch control command arrive or the keypad brightness data arrive? if have order or data to arrive, carry out S602, otherwise carry out S601;
S602: by the supervisory keyboard backlight module, regulate the keyboard backlight illumination.Then carry out S601.
The foregoing is only preferred embodiment of the present invention, all equalizations of doing according to the claims in the present invention scope change and modify, and all should belong to the covering scope of the claims in the present invention.