CN101980331B - Method for adjusting luminance of light-emitting diode (LED) display screen - Google Patents

Abstract

The invention discloses a method for adjusting the luminance of an LED display screen, which comprises the following steps of: acquiring the original grey scale data N of each pixel point of the LED display screen; performing nonlinear transformation on the original grey scale data N to obtain the grey scale data M after data bit expansion; and adjusting the luminance of each pixel point according to a formula of L=M*K, wherein L is an attenuated luminance value and K is a preset luminance attenuation coefficient. Compared with the prior art, the embodiment of the invention has the advantage that: the data bit expansion is performed on the grey scale data in the invention, so that the high-grey scale display of the LED display screen under low luminance is realized, the loss of original grey scale signals is prevented, and the image display quality is greatly improved.

Description

A kind of luminance regulating method of LED display

Technical field

The present invention relates to the LED display technical field, relate in particular to a kind of luminance regulating method of LED display.

Background technology

People come from eyes to the acquisition of information more than 90 percent; LED display is as a kind of visual device for display of message; Have that information is variable, color is abundant, brightness is high, the visual angle is big, visual range is far away, low in energy consumption, advantages such as reliability is high, the life-span is long, specification is wide in variety, waterproof, can satisfy the demand of various different application scenes, development prospect is boundless; Being acknowledged as tool growth potential also is LED application market with fastest developing speed, at present extensively in industry-by-industry.For LED display; The problem that must consider has color, sharpness, gray scale, brightness regulation etc.; Because the variation range bigger (such as daytime and night) of outdoor environment light; The information that LED display is shown can be high-visible under the environmental background light of various intensity; Just require the luminosity of LED display to do corresponding adjustment,, cause the observer clearly to distinguish information even produce dizzy sensation in order to avoid LED display seems bright inadequately or under the low-light level environment, seem dazzling under high-brightness environment along with the variation of environmental background light.The brightness adjusting method of traditional LED display is: the gradation data N that at first obtains each pixel on the LED display; Again (wherein according to L=N * K; K is the brightness decay coefficient according to the current environment brightness settings, and L is the brightness value after decaying) brightness of each pixel is adjusted.Yet present domestic LED display mainly adopts 8 disposal systems, also is 256 grades of gray scales; Thereby when adopting classic method to reduce the brightness of LED display; The gray scale performance variation of each pixel, the most information of original displayed image is lost, and finally causes the serious distortion of image; For example, be 256 grey levels to be arranged at 1 o'clock in the brightness decay COEFFICIENT K, grey scale signal does not lose, and is that the brightness after the decay in 10% o'clock only has 27 grey levels in the brightness decay COEFFICIENT K, and this moment, a large amount of original grey scale signals were lost.

Summary of the invention

The object of the present invention is to provide a kind of luminance regulating method of LED display, solve LED display in problem than the distortion of low-light level hypograph.

The embodiment of the invention is achieved in that

A kind of luminance regulating method of LED display may further comprise the steps:

Obtain the original gradation data N of each pixel of LED display;

Said original gradation data N is carried out nonlinear transformation, obtain the gradation data M after data bit is expanded;

According to formula L=M * K the brightness of said each pixel is adjusted; Wherein, L is preset brightness decay coefficient for the brightness value after decaying, K.

In the said method, said original gradation data N is carried out nonlinear transformation according to following formula:

$M={\left(\frac{N}{256}\right)}^a\×2^b$

Wherein, N is an original gradation data, and M is the gradation data after the data bit expansion, and a is preset curtain index, and b is preset expansion figure place and b＞8.

In the said method, said b is preset as 14 or 16.

The embodiment of the invention compared with prior art; Beneficial effect is: the present invention adopts the mode of gradation data being carried out the data bit expansion; Realized that LED display high gray scale under low-light level shows, prevented losing of original grey scale signal, improved the picture display quality greatly.

Description of drawings

Fig. 1 is the luminance regulating method process flow diagram of the LED display that provides of the embodiment of the invention.

Embodiment

In order to make the object of the invention, technical scheme and advantage clearer,, the present invention is further elaborated below in conjunction with accompanying drawing and embodiment.Should be appreciated that specific embodiment described herein only in order to explanation the present invention, and be not used in qualification the present invention.

See also Fig. 1, the luminance regulating method of LED display may further comprise the steps in the present embodiment:

101, obtain the digital of digital video data of LED display, this digital of digital video data is the DVI-D form, has comprised the gradation data (gradation data that comprises three kinds of colors of R/G/B, each gradation data are 8, have 256 grey levels altogether) of each pixel.

102, above-mentioned gradation data is carried out nonlinear transformation, so that this gradation data of 8 is expanded to the gradation data greater than 8.Wherein, the expansion figure place can be set arbitrarily, is preferably 14 or 16; Have 16384 grey levels when expanding to 14, have 65536 grey levels when expanding to 16, thereby can vacate many levels rank when being filled into former 8 gradation data in 16384 rank or the 65536 rank forms, this just provides the space for nonlinear transformation.

In this step, can 1. carry out the expansion of data bit according to formula;

$M={\left(\frac{N}{256}\right)}^a\×2^b$ ①

Wherein, M is the gradation data value after the data bit expansion, and N is the preceding 8Bit gradation data value of expansion, the curtain index of a for setting, and b is the expansion figure place of setting.

Formula 1. in, power exponent can define arbitrarily, also can change grey level quantity through defining different power exponents.

103, according to formula L=M * K the brightness of each pixel is adjusted; Wherein, L is preset brightness decay coefficient for the brightness value after decaying, K.

Adopt said method; If gradation data has been carried out 14 expansions, then when power exponent does not change, luminance factor is to have 250 grey levels at 1 o'clock; Still have 226 grey levels during luminance factor 10%; Do not change and then have only 27 grey levels for former 8, thus with classic method relatively, the present invention has improved the picture display quality of LED display under the low-light level greatly.

The above is merely preferred embodiment of the present invention, not in order to restriction the present invention, all any modifications of within spirit of the present invention and principle, being done, is equal to and replaces and improvement etc., all should be included within protection scope of the present invention.

Claims (2)

1. the luminance regulating method of a LED display is characterized in that, this method may further comprise the steps:

Obtain the original gradation data N of each pixel of LED display;

Said original gradation data N is carried out nonlinear transformation, obtain the gradation data M after data bit is expanded;

N is an original gradation data; M is the gradation data after the data bit expansion; A is preset curtain index, and b is preset expansion figure place and b＞8;

According to formula L=M * K the brightness of said each pixel is adjusted; Wherein, L is preset brightness decay coefficient for the brightness value after decaying, K.

2. the luminance regulating method of LED display as claimed in claim 1 is characterized in that, said b is preset as 8＜b＜16 or b=16.

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