CN105989579A - Image enhancement method and device - Google Patents

Abstract

The invention discloses an image enhancement method and device. The method comprises windows of different sizes are selected by taking pixel points of an image as centers respectively, the mean value of all the pixel points in each scale is calculated, and the windows are smaller than a present size; for each pixel point, the difference between the pixel value itself and the mean value of the pixel values in all sizes is calculated; a gain multiple is obtained, and an enhancement increment corresponding to the difference is calculated; a corrected enhancement increment, which equals the product of the enhancement increment and the gain multiple, is added to an original pixel value of each pixel point; and the corrected enhancement increment of each pixel point replaces the original pixel value. According to technical schemes of the invention, a better image enhancement effect can be achieved via relatively low computing complexity.

Description

A kind of image enchancing method and device

Technical field

The present invention relates to image processing field, particularly relate to a kind of image enchancing method and device.

Background technology

Image enhaucament generally refers to the edge in the presence of image and detail section are carried out enhancement process, figure Image intensifying, as an importance of image procossing, has critically important practical significance.

In current technology, some method is relatively more general to the reinforced effects of image, such as based on direction ladder Although the method for degree can preferably strengthen continuum boundary, but the indefinite edge of directional, such as word Corner, then strengthen not；Some method computation complexity is the highest, and the requirement to hardware is the highest, therefore Cost is relatively big, the Enhancement Method such as kept based on edge, or image deblurring method, they tools There is higher computation complexity, higher to hardware requirement, it is more difficult to realize at mobile phone terminal, image being carried out in real time Process.Therefore, in existing technology, it is impossible to realize the cost so that computation complexity is the highest and obtain preferably Image enhancement effects.

Summary of the invention

In view of this, the invention provides a kind of image enchancing method and device, it is possible to computation complexity The highest cost obtains preferable image enhancement effects.

For achieving the above object, the present invention provides following technical scheme:

A kind of image enchancing method, including:

Respectively centered by the pixel of each in image, choose the window of multiple different scale size, meter Calculate the pixel value average of all pixels under each yardstick；Described window is less than presetting yardstick；

To each pixel in image, calculate self pixel value equal with described pixel value under all yardsticks Difference between value；

Obtain gain factor, calculate the enhancing increment corresponding with described difference；

To each pixel, the original pixel value of pixel is strengthened increment plus revising, obtain revising pixel Value；Described revise strengthen that increment is described enhancing increment with described gain factor long-pending；

The described correction pixel value of each pixel is replaced described original pixel value.

Preferably, choose the window of 3 different scale sizes, calculate all pixels under each yardstick respectively The pixel value average of point.

Preferably, in the window of the plurality of different scale size, the number of row is all not more than 7.

Preferably, the enhancing increment that described calculating is corresponding with described difference includes:

Determine that the maximum in described difference is described enhancing increment；

Or determine that the intermediate value in described difference is described enhancing increment；

Or calculate the meansigma methods of described difference as described enhancing increment；

Or calculate the pixel value variance of all pixels under each yardstick, by the variance under each yardstick To the described difference distribution weight corresponding with described yardstick, calculate described enhancing increment.

Preferably, the enhancing increment that described calculating is corresponding with described difference includes:

When described gain factor is more than 0, determine that the described difference under the yardstick corresponding to first variance is Described enhancing increment；Described first variance is the maximum of pixel value variance under all yardsticks.

Preferably, the value of described gain factor is more than 0.

A kind of image intensifier device, including:

First computing module, centered by the pixel of each in image respectively, chooses multiple difference The window of scale size, calculates the pixel value average of all pixels under each yardstick；Described window is less than Preset yardstick；

Second computing module, for each pixel in image, calculates self pixel value with all Difference between described pixel value average under yardstick；

3rd computing module, is used for obtaining gain factor, calculates the enhancing increment corresponding with described difference；

4th computing module, for each pixel, strengthening the original pixel value of pixel plus revising Increment, obtains revising pixel value；Described enhancing increment of revising is described enhancing increment and described gain factor Long-pending；

Replacement module, for replacing described original pixel value by the described correction pixel value of each pixel.

Preferably, described 3rd computing module includes:

Gain factor acquiring unit, is used for obtaining described gain factor；

Strengthen incremental computations unit, for calculating the enhancing increment corresponding with described difference.

Preferably, described enhancing incremental computations unit includes:

First computation subunit, for determining that the maximum in described difference is described enhancing increment；

Second computation subunit, for determining that the intermediate value in described difference is described enhancing increment；

3rd computation subunit, for calculating the meansigma methods of described difference as described enhancing increment；

4th computation subunit, for calculating the pixel value variance of all pixels under each yardstick, passes through The described difference distribution weight that variance pair under each yardstick is corresponding with described yardstick, calculates described enhancing Increment.

Preferably, described enhancing incremental computations unit includes:

5th computation subunit, for when described gain factor is more than 0, determining corresponding to first variance Yardstick under described difference be described enhancing increment；Described first variance is pixel value side under all yardsticks The maximum of difference.

Understand via above-mentioned technical scheme, compared with prior art, the invention provides a kind of image and increase Strong method and device.The technical scheme using the present invention to provide, with each pixel in image be respectively Center, chooses the window of multiple different scale size, calculates the pixel value of all pixels under each yardstick Average；Described window is less than presetting yardstick；To each pixel in image, calculate self pixel value And difference between described pixel value average under all yardsticks；Obtain gain factor, calculate and described difference Corresponding enhancing increment；To each pixel, the original pixel value of pixel is strengthened increment plus revising, Obtain revising pixel value；Described revise strengthen that increment is described enhancing increment with described gain factor long-pending； The described correction pixel value of each pixel is replaced described original pixel value.The technical side that the present invention provides Case, chooses the window of multiple different scale size centered by each pixel, and described window is less than presetting Yardstick, belongs to the process window that tradition is less, by multiple different scale windows are analyzed and are calculated Method realize the preferable image enhancement processing of effect, and computation complexity is the highest, it is possible to avoid existing Technology is because of higher the caused more difficult problem realized at mobile phone terminal of computation complexity.Therefore, the present invention carries The numerical procedure of confession, it is possible to obtain preferable image enhancement effects with the cost that computation complexity is the highest.

Accompanying drawing explanation

In order to be illustrated more clearly that the embodiment of the present invention or technical scheme of the prior art, below will be to reality Execute the required accompanying drawing used in example or description of the prior art to be briefly described, it should be apparent that below, Accompanying drawing in description is only embodiments of the invention, for those of ordinary skill in the art, not On the premise of paying creative work, it is also possible to obtain other accompanying drawing according to the accompanying drawing provided.

The flow chart of a kind of image enchancing method that Fig. 1 provides for the embodiment of the present invention；

The curve chart of a kind of gain factor value that Fig. 2 provides for the embodiment of the present invention；

The structure chart of a kind of image intensifier device that Fig. 3 provides for the embodiment of the present invention；

Fig. 4 a is an original image；

Fig. 4 b is Fig. 4 a picture after technical solution of the present invention processes；

Fig. 5 a is an other original image；

Fig. 5 b is Fig. 5 a picture after technical solution of the present invention processes；

Fig. 6 a is an other original image；

Fig. 6 b is Fig. 6 a picture after technical solution of the present invention processes.

Detailed description of the invention

Below in conjunction with the accompanying drawing in the embodiment of the present invention, the technical scheme in the embodiment of the present invention is carried out Clearly and completely describe, it is clear that described embodiment is only a part of embodiment of the present invention, and It is not all, of embodiment.Based on the embodiment in the present invention, those of ordinary skill in the art are not doing Go out the every other embodiment obtained under creative work premise, broadly fall into the scope of protection of the invention.

Understandable, below in conjunction with the accompanying drawings for enabling the above-mentioned purpose of the present invention, feature and advantage to become apparent from The present invention is further detailed explanation with detailed description of the invention.

Embodiment

Refer to the flow chart of a kind of image enchancing method that Fig. 1, Fig. 1 provide for the embodiment of the present invention.As Shown in Fig. 1, the method includes:

Step S101, respectively centered by the pixel of each in image, chooses multiple different scale size Window, calculate the pixel value average of all pixels under each yardstick；Described window is less than presetting yardstick；

Concrete, it is positioned at the pixel of the window center of the plurality of different scale size, the most named Strengthen a little in advance, by its pixel value, be designated as x_center.Then centered by pre-enhancing point, choose multiple difference The window of scale size, calculates the pixel value average of all pixels under each yardstick；

Concrete, the window of the plurality of different scale size is optionally, for square, the most described many The window of individual different scale size, the window number on four limits of external boundary is equal；The plurality of difference The window of scale size can be other shapes, such as rhombus, other window-shaped based on multiscale idea Shape falls within protection scope of the present invention.

The technical scheme that the present invention provides, selected maximum window, the most traditional window, institute The window of the out to out chosen, the number of the row comprised, optionally, no more than 7.The application present invention The technical scheme provided, the window choosing three different scale sizes just can obtain preferable reinforced effects.

Further, optionally, centered by pre-enhancing point, the window of three different scale sizes is chosen, With the first yardstick 3*3, as a example by the window of the second yardstick 5*5 and the 3rd yardstick 7*7, (other yardstick also should be In protection scope of the present invention), it is denoted as W3, W5, W7.The pixel value of central point is x_center。 Table 1 is the window of the first yardstick, and table 2 is the window of the second yardstick, and table 3 is the window of the 3rd yardstick, As follows:

Wherein, number N3=9 of pixel under the first yardstick, number N5=25 of pixel under the second yardstick, Number N7=49 of pixel under 3rd yardstick.Calculate the pixel value average of all pixels under each yardstick, That is, W3, the pixel value average in W5, W7 are calculatedSuch as being calculated as of W3:

${\stackrel{\‾}{x}}_3=\frac{\underset{i=1}{\overset{i=9}{\mathrm{\Σ}}}{x}_i}{N_3}---\left(1\right)$

Step S102, to each pixel in image, calculates self pixel value and institute under all yardsticks State the difference between pixel value average；

Concrete, still with W3, as a example by the window of tri-scale size of W5, W7,

$\mathrm{\Δ}{x}_3=x_{\mathrm{center}}-{\stackrel{\‾}{x}}_3---\left(2\right)$

$\mathrm{\Δ}{x}_5=x_{\mathrm{center}}-{\stackrel{\‾}{x}}_5---\left(3\right)$

$\mathrm{\Δ}{x}_7=x_{\mathrm{center}}-{\stackrel{\‾}{x}}_7---\left(4\right)$

Wherein, Δ x₃In the pixel value put for pre-enhancing and W3 between the pixel value average of all pixels Difference, Δ x₅For difference between the pixel value average of all pixels in the pre-pixel value strengthening point and W5, Δx₇For difference between the pixel value average of all pixels in the pre-pixel value strengthening point and W7.

Step S103, obtains gain factor, calculates the enhancing increment corresponding with described difference；

Concrete, obtain the gain factor pre-set.Optionally, described gain factor is designated as k.

Concrete, the described calculating enhancing increment corresponding with described difference (such as, it is designated as Δ x) to include:

Determine that the maximum in described difference is described enhancing increment；

Concrete, still with W3, as a example by the window of tri-scale size of W5, W7, determine Δ x₃、Δx₅With Δx₇Maximum in three is described enhancing increment.

Or determine that the intermediate value in described difference is described enhancing increment；

Concrete, still with W3, as a example by the window of tri-scale size of W5, W7, determine Δ x₃、Δx₅With Δx₇The value occupying centre in three is described enhancing increment.

Or calculate the meansigma methods of described difference as described enhancing increment；

Concrete, still with W3, as a example by the window of tri-scale size of W5, W7, determine Δ x₃、Δx₅With Δx₇The meansigma methods of three is described enhancing increment.

Or calculate the pixel value variance of all pixels under each yardstick, by the variance under each yardstick To the described difference distribution weight corresponding with described yardstick, calculate described enhancing increment；

Concrete, still with W3, as a example by the window of tri-scale size of W5, W7, calculate under each yardstick The pixel value variance of all pixels, calculates W3 the most respectively, the pixel value variance in W5, W7 σ₃, σ₅, σ₇；Such as being calculated as in W3:

${\mathrm{\σ}}_3=\frac{\underset{i=1}{\overset{i=9}{\mathrm{\Σ}}}{\left(x_i\right)}^2}{N_3}-{\left(\frac{\underset{i=1}{\overset{i=9}{\mathrm{\Σ}}}{x}_i}{N_3}\right)}^2---\left(5\right)$

Then by the described difference distribution weight that the variance pair under each yardstick is corresponding with described yardstick, Calculate described enhancing increment Delta x；

$\mathrm{\ΔX}=\left\{\begin{array}{cc}\frac{{\mathrm{\σ}}_3\×\mathrm{\Δ}{x}_3+{\mathrm{\σ}}_5\×\mathrm{\Δ}{x}_5+{\mathrm{\σ}}_7\×\mathrm{\Δ}{x}_7}{{\mathrm{\σ}}_3+{\mathrm{\σ}}_5+{\mathrm{\σ}}_7}& ({\mathrm{\σ}}_3+{\mathrm{\σ}}_5+{\mathrm{\σ}}_7\≠0)\\ 0& ({\mathrm{\σ}}_3+{\mathrm{\σ}}_5+{\mathrm{\σ}}_7=0)\end{array}\right.---\left(6\right)$

Concrete, optionally, when described gain factor is more than 0, determine the chi corresponding to first variance Described difference under Du is described enhancing increment Delta x；Described first variance is pixel value variance under all yardsticks Maximum.Concrete, still with W3, as a example by the window of tri-scale size of W5, W7, it is assumed that σ₃, σ₅, σ₇Maximum in three is σ₃, the most described first variance is σ₃, determine and σ₃Corresponding Described difference DELTA x of yardstick W3₃For described enhancing increment Delta x.

Step S104, to each pixel, strengthens increment by the original pixel value of pixel plus revising, To revising pixel value；Described revise strengthen that increment is described enhancing increment with described gain factor long-pending；

Concrete, x '_center=x_center+k*Δx； (7)

Wherein, x_centerFor the pre-original pixel value strengthening pixel, x '_centerFor revising pixel value, k* Δ x is Revise and strengthen increment.It should be noted that the value of described gain factor k, for positive number, zero or negative, When described gain factor k is positive number (i.e. the numerical value more than 0), it is possible to realize the reinforced effects to image, Concrete, the value of k is the biggest, and reinforced effects is the strongest, typically, when k takes 1, just has been able to be compared Stronger reinforced effects.When described gain factor k is negative, it is possible to realize the noise reduction process to image.

Step S105, replaces described original pixel value by the described correction pixel value of each pixel.

Concrete, replacing of each pixel pixel value of being capable of in image through described step S105 Change, replace with through enhanced described correction pixel value, thus realize the enhancement process to image.

Understand via above-mentioned technical scheme, compared with prior art, the invention provides a kind of image and increase Strong method and device.The technical scheme using the present invention to provide, with each pixel in image be respectively Center, chooses the window of multiple different scale size, calculates the pixel value of all pixels under each yardstick Average；Described window is less than presetting yardstick；To each pixel in image, calculate self pixel value And difference between described pixel value average under all yardsticks；Obtain gain factor, calculate and described difference Corresponding enhancing increment；To each pixel, the original pixel value of pixel is strengthened increment plus revising, Obtain revising pixel value；Described revise strengthen that increment is described enhancing increment with described gain factor long-pending； The described correction pixel value of each pixel is replaced described original pixel value.The technical side that the present invention provides Case, chooses the window of multiple different scale size centered by each pixel, and described window is less than presetting Yardstick, belongs to the process window that tradition is less, by multiple different scale windows are analyzed and are calculated Method realize the preferable image enhancement processing of effect, and computation complexity is the highest, it is possible to avoid existing Technology is because of higher the caused more difficult problem realized at mobile phone terminal of computation complexity.Therefore, the present invention carries The numerical procedure of confession, it is possible to obtain preferable image enhancement effects with the cost that computation complexity is the highest.

It should be noted that during to image enhaucament, in order to not make Noise enhancement excessively obvious, Optionally, the span of gain factor K is set: k ∈ (-k_dn, k_ee), k_dnAnd k_eeIt is all positive number, It is respectively intended to characterize denoising and the intensity of enhancing, general k_dnValue between 0 to 1, and k_dnIt is worth the biggest Removing-noise strength is the biggest, is analogous to the intensity of mean filter, k when taking 1_dnValue be usually no more than 1, no Then it is likely to occur not good enough effect (artifacts).k_eeValue, the most also between 0 to 1, experiment card Bright being taken as almost all of image when 1 has had stronger reinforced effects, in theory k_eeValue Can be more than 1.By the experiment of some video flowings, the present invention provides k_dnWith k_eeThe value allusion quotation of maximum Offset is respectively 8/16 and 10/16.

It addition, the present invention also provides for the computational methods of another gain factor k value.Refer to Fig. 2, The curve chart of a kind of gain factor value that Fig. 2 provides for the embodiment of the present invention.Calculate for simplifying, here Only use σ₃,σ₅,σ₇Between absolute difference maximum max_delt_sigma [i.e. max (| σ₃-σ₅|, |σ₃-σ₇|, | σ₇-σ₅|)], (or use σ as the factor of measurement₃, σ₅, σ₇Variances sigma between three_σMake For weighing factor).

${\mathrm{\σ}}_{\mathrm{\σ}}=\frac{\underset{i=1}{\overset{i=3}{\mathrm{\Σ}}}{\left({\mathrm{\σ}}_i\right)}^2}{3}-{\left(\frac{\underset{i=1}{\overset{i=3}{\mathrm{\Σ}}}{\mathrm{\σ}}_i}{3}\right)}^2---\left(8\right)$

As in figure 2 it is shown, as max_delt_sigma, < during delt_sigma_th_m, K takes negative value for filtering The effect of denoising, as max_delt_sigma > delt_sigma_th_m time, K takes on the occasion of for image enhaucament Effect.Max_delt_sigma is to filter by force district between [0, delt_sigma_th_l], [delt_sigma_th_l, Delt_sigma_th_m] between for filtering transition region, [delt_sigma_th_m, delt_sigma_th_h] it Between for strengthening transition region, more than being strong enhancement region during delt_sigma_th_h.

Wherein, delt_sigma_th_l is at x_centerTime the biggest the most bigger, this is because other factors one During sample, x_centerDuring increase, noise level also can increase, due to noise random distribution, probability On cause max_delt_sigma the biggest.

The present invention provides a kind of obtaining value method of delt_sigma_th_l:

Delt_sigma_th_l=k_g*x_center (9)

A kind of typical value of such as k_g is 4/128, with k_dnAnd k_eeIt is respectively used to regulate denoising and enhancing Intensity different, k_g is regulation image entirety deflection denoising or the parameter of enhancing, more district during increase Territory processes in the way of denoising, and during minimizing, more region is enhanced.And for delt_sigma_th_m and Delt_sigma_th_h, calculates for simplifying, optionally, according to x_centerCarry out segmentation and take fixed value.Need Illustrate, more than simply a kind of implementation, set up the purpose of transition region be make image more smooth and Natural, transition region not necessarily uses the mode of linear realization, the most for the purpose of simplifying the description.

During by foregoing it can be seen that described gain factor k takes negative value, the technical side that the present invention provides Case, additionally it is possible to realize the noise reduction process to image.

In order to more comprehensively illustrate technical scheme, the invention also discloses a kind of image enhaucament Device.

Refer to the structure chart of a kind of image intensifier device that Fig. 3, Fig. 3 provide for the embodiment of the present invention.As Shown in Fig. 3, this device includes:

First computing module 301, centered by the pixel of each in image respectively, choose multiple not With the window of scale size, calculate the pixel value average of all pixels under each yardstick；Described window is little In default yardstick；

Second computing module 302, for each pixel in image, calculates self pixel value and institute There is the difference between described pixel value average under yardstick；

3rd computing module 303, is used for obtaining gain factor, calculates the enhancing corresponding with described difference and increases Amount；

4th computing module 304, for each pixel, increasing the original pixel value of pixel plus revising Strong increment, obtains revising pixel value；Described enhancing increment of revising is described enhancing increment and described gain times Amassing of number；

Replacement module 305, for replacing described original pixel value by the described correction pixel value of each pixel.

Concrete, described 3rd computing module 303 includes:

Gain factor acquiring unit, is used for obtaining described gain factor；

Strengthen incremental computations unit, for calculating the enhancing increment corresponding with described difference.

Further, described enhancing incremental computations unit includes:

First computation subunit, for determining that the maximum in described difference is described enhancing increment；

Second computation subunit, for determining that the intermediate value in described difference is described enhancing increment；

3rd computation subunit, for calculating the meansigma methods of described difference as described enhancing increment；

4th computation subunit, for calculating the pixel value variance of all pixels under each yardstick, passes through The described difference distribution weight that variance pair under each yardstick is corresponding with described yardstick, calculates described enhancing Increment.

Further, described enhancing incremental computations unit also includes:

5th computation subunit, for when described gain factor is more than 0, determining corresponding to first variance Yardstick under described difference be described enhancing increment；Described first variance is pixel value side under all yardsticks The maximum of difference.

Respectively as shown in Fig. 4 a, Fig. 4 b, Fig. 5 a, Fig. 5 b, Fig. 6 a and Fig. 6 b, Fig. 4 a be one former Beginning picture, the picture that Fig. 4 b is Fig. 4 a after technical solution of the present invention processes, Fig. 5 a be other one former Beginning picture, the picture that Fig. 5 b is Fig. 5 a after technical solution of the present invention processes, Fig. 6 a be other one former Beginning picture, Fig. 6 b is Fig. 6 a picture after technical solution of the present invention processes.Contrast it can be found that, this The technical scheme that inventive embodiments provides, it is possible to image is realized good reinforced effects.

Finally, in addition it is also necessary to explanation, in this article, the relational terms of such as first and second or the like It is used merely to separate an entity or operation with another entity or operating space, and not necessarily requires Or imply relation or the order that there is any this reality between these entities or operation.And, art Language " includes ", " comprising " or its any other variant are intended to comprising of nonexcludability, thus Make to include that the process of a series of key element, method, article or equipment not only include those key elements, and Also include other key elements being not expressly set out, or also include for this process, method, article or The key element that person's equipment is intrinsic.In the case of there is no more restriction, by statement " including ... " The key element limited, it is not excluded that also deposit in including the process of described key element, method, article or equipment In other identical element.

In this specification, each embodiment uses the mode gone forward one by one to describe, and each embodiment stresses Being the difference with other embodiments, between each embodiment, identical similar portion sees mutually. For device disclosed in embodiment, owing to it corresponds to the method disclosed in Example, so describing Fairly simple, relevant part sees method part and illustrates.

The method described in conjunction with the embodiments described herein or the step of algorithm can directly use hardware, The software module that processor performs, or the combination of the two implements.Software module can be placed in and deposit at random Reservoir (RAM), internal memory, read only memory (ROM), electrically programmable ROM, electric erasable can Well known in programming ROM, depositor, hard disk, moveable magnetic disc, CD-ROM or technical field In any other form of storage medium.

Described above to the disclosed embodiments, makes professional and technical personnel in the field be capable of or uses The present invention.Multiple amendment to these embodiments will be aobvious and easy for those skilled in the art See, generic principles defined herein can without departing from the spirit or scope of the present invention, Realize in other embodiments.Therefore, the present invention is not intended to be limited to the embodiments shown herein, And it is to fit to the widest scope consistent with principles disclosed herein and features of novelty.

Claims (10)

1. an image enchancing method, it is characterised in that including:

Respectively centered by the pixel of each in image, choose the window of multiple different scale size, meter Calculate the pixel value average of all pixels under each yardstick；Described window is less than presetting yardstick；

To each pixel in image, calculate self pixel value equal with described pixel value under all yardsticks Difference between value；

Obtain gain factor, calculate the enhancing increment corresponding with described difference；

To each pixel, the original pixel value of pixel is strengthened increment plus revising, obtain revising pixel Value；Described revise strengthen that increment is described enhancing increment with described gain factor long-pending；

The described correction pixel value of each pixel is replaced described original pixel value.

Method the most according to claim 1, it is characterised in that choose 3 different scale sizes Window, calculates the pixel value average of all pixels under each yardstick respectively.

Method the most according to claim 1, it is characterised in that the plurality of different scale size In window, the number of row is all not more than 7.

Method the most according to claim 1, it is characterised in that described calculating is relative with described difference The enhancing increment answered includes:

Determine that the maximum in described difference is described enhancing increment；

Or determine that the intermediate value in described difference is described enhancing increment；

Or calculate the meansigma methods of described difference as described enhancing increment；

Or calculate the pixel value variance of all pixels under each yardstick, by the variance under each yardstick To the described difference distribution weight corresponding with described yardstick, calculate described enhancing increment.

Method the most according to claim 1, it is characterised in that described calculating is relative with described difference The enhancing increment answered includes:

When described gain factor is more than 0, determine that the described difference under the yardstick corresponding to first variance is Described enhancing increment；Described first variance is the maximum of pixel value variance under all yardsticks.

Method the most according to claim 1, it is characterised in that the value of described gain factor is more than 0.

7. an image intensifier device, it is characterised in that including:

First computing module, centered by the pixel of each in image respectively, chooses multiple difference The window of scale size, calculates the pixel value average of all pixels under each yardstick；Described window is less than Preset yardstick；

Second computing module, for each pixel in image, calculates self pixel value with all Difference between described pixel value average under yardstick；

3rd computing module, is used for obtaining gain factor, calculates the enhancing increment corresponding with described difference；

4th computing module, for each pixel, strengthening the original pixel value of pixel plus revising Increment, obtains revising pixel value；Described enhancing increment of revising is described enhancing increment and described gain factor Long-pending；

Replacement module, for replacing described original pixel value by the described correction pixel value of each pixel.

Device the most according to claim 7, it is characterised in that described 3rd computing module includes:

Gain factor acquiring unit, is used for obtaining described gain factor；

Strengthen incremental computations unit, for calculating the enhancing increment corresponding with described difference.

Device the most according to claim 8, it is characterised in that described enhancing incremental computations unit bag Include:

First computation subunit, for determining that the maximum in described difference is described enhancing increment；

Second computation subunit, for determining that the intermediate value in described difference is described enhancing increment；

3rd computation subunit, for calculating the meansigma methods of described difference as described enhancing increment；

4th computation subunit, for calculating the pixel value variance of all pixels under each yardstick, passes through The described difference distribution weight that variance pair under each yardstick is corresponding with described yardstick, calculates described enhancing Increment.

Device the most according to claim 8, it is characterised in that described enhancing incremental computations unit Including:

5th computation subunit, for when described gain factor is more than 0, determining corresponding to first variance Yardstick under described difference be described enhancing increment；Described first variance is pixel value side under all yardsticks The maximum of difference.