CN1684107A - How to adjust image contrast - Google Patents
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- CN1684107A CN1684107A CN 200410033480 CN200410033480A CN1684107A CN 1684107 A CN1684107 A CN 1684107A CN 200410033480 CN200410033480 CN 200410033480 CN 200410033480 A CN200410033480 A CN 200410033480A CN 1684107 A CN1684107 A CN 1684107A
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Abstract
The invention relates to a method for adjusting image contrast, which comprises the steps of constructing a brightness histogram of an original image, analyzing image characteristics of the brightness histogram, and judging whether the image characteristics are peak protrusion, image brightness or image darkness. After a control point is determined by proper operation, a linear equation connected by the control point and the contrast value can be established in a rectangular coordinate system by matching with the contrast value to be adjusted. The mapping of the linear equation can relatively calculate the corresponding relationship between the coordinates of the horizontal axis and the coordinates of the vertical axis of the rectangular coordinate system, a gamma table is established according to the corresponding relationship, the input brightness of each pixel point of the original image is utilized by a table look-up method, the brightness value which is correspondingly output can be found from the gamma table, and the contrast of the original image is adjusted. Therefore, after the original image is subjected to contrast adjustment of the gamma table, the brightness can be uniformly expanded, and ideal contrast image output is achieved.
Description
Technical field
The present invention relates to a kind of method of adjustment of picture contrast, particularly a kind of in image processing software to the intensive treatment of digital picture contrast.
Background technology
The contrast of image (contrast) is meant its Luminance Distribution, and common low contrast or the image of high-contrast is regarded as relatively poor contrast effect, wherein the image of high-contrast presents a kind of coarse brightness, the image of low contrast then presents a kind of outward appearance of fading, these two kinds all can't make people's vision reach satisfied effect, therefore on behalf of its brightness, a good contrast image can evenly be expanded to each color range.Yet when adjusting contrast brightness,, often cause image too bright or too dark easily with conventional images software, therefore make image fault, and can't allow the beholder obtain satisfied visual effect because the adjustment of picture contrast is bigger.
Summary of the invention
Fundamental purpose of the present invention is to provide a kind of picture contrast method of adjustment, can provide a kind of speed faster, more level and smooth contrast adjustment relatively according to the characteristic that image presented, and adjusts effect to obtain preferable picture contrast.
In order to achieve the above object, the invention provides a kind of method of adjustment of picture contrast, comprise the following steps: to construct the brightness histogram (luminance histogram) of an original image; The characteristics of image of analyzing this brightness histogram is to determine a reference mark; Capture a contrast value; In a rectangular coordinate system, set up by this reference mark and a straight line equation that this contrast value connected; Set up a gamma table (gamma table) according to this equation of line; Reach the contrast of adjusting this original image according to this gamma table.
The present invention also provides a kind of picture contrast method of adjustment, comprises the following steps: to construct a brightness histogram of an original image; Judge whether this brightness histogram has crest outstanding; When this brightness histogram has crest outstanding, then carry out the slicing processing and obtain a slicing brightness histogram; Calculate the center of gravity of this slicing brightness histogram and as a reference mark; Capture a contrast value; In a rectangular coordinate system, set up by this reference mark and a straight line equation that this contrast value connected; Set up a gamma table according to this equation of line; Reach the contrast of adjusting this original image according to this gamma table.
Another kind of picture contrast method of adjustment provided by the invention comprises the following steps: to construct a brightness histogram of an original image; The average brightness and the luminance standard that calculate this brightness histogram are poor; Judge whether this average brightness is bright partially or dark partially; This average brightness and this luminance standard difference are carried out computing and obtain a reference mark; Capture a contrast value; In a rectangular coordinate system, set up by this reference mark and a straight line equation that this contrast value connected; Set up a gamma table (gammatable) according to this equation of line; Reach the contrast of adjusting this original image according to this gamma table.
The present invention is by aforesaid step, and the gamma table of being set up out can reflect the characteristics of image that original image contains, and makes that brightness can evenly launch after the contrast adjustment of original image via gamma table, and reaches desirable contrast image output.
Description of drawings
Figure 1A is the synoptic diagram of an original image;
Figure 1B is the brightness histogram of Figure 1A;
Fig. 2 is the rectangular plots of zero equation of line for contrast of the present invention;
The process flow diagram that Fig. 3 adjusts for picture contrast of the present invention;
Fig. 4 is the rectangular plots of 30 equation of line for contrast of the present invention;
Fig. 5 A is the synoptic diagram that contains the original image of background image;
Fig. 5 B utilizes the equation of line F of Fig. 4 for Fig. 5 A
1Adjust the synoptic diagram of picture contrast gained;
Fig. 6 A is the synoptic diagram that does not contain the original image of background image;
Fig. 6 B utilizes the equation of line F of Fig. 4 for Fig. 6 A
1Adjust the synoptic diagram of picture contrast gained; And
Fig. 7 is the rectangular plots of contrast of the present invention for negative 30 equation of line.
Embodiment
In image processing techniques, often the numerical data that can use picture characteristics especially is applied in contrast image and handles as analytical applications, determines image quality to handle the great key of quality especially.The present invention strengthens or weakens processing according to picture characteristics distribution (image histogram) to image degree of comparing when picture contrast is handled.
The picture characteristics that the present invention uses is distributed as brightness histogram (luminance histogram), but there are how many pictorial elements to be distributed in the different luminance areas via the understanding of brightness histogram let us, the horizontal ordinate of brightness histogram is from 0 to 255 brightness, promptly being the brightness of 8 positions, is the quantity that belongs to same brightness portrait element and its ordinate manifested.
See also the synoptic diagram that Figure 1A is an original image, and the brightness histogram that goes out via COMPUTER CALCULATION is shown in Figure 1B.And in Figure 1B we can to utilize method provided by the present invention therefrom to judge original image be bright partially or dark partially, and with the equation of line F in the rectangular coordinate system shown in Figure 2
0, come original image is adjusted contrast.Wherein be the respective function of brightness relation between the horizontal ordinate of Fig. 2 and the ordinate, horizontal ordinate is represented the input brightness of original image, ordinate be image through the adjusted output brightness of contrast, equation of line F
0The reflection function can be regarded as, brightness can be obtained exporting relatively after the reflection of input brightness via the reflection function.
And the present invention adopts equation of line as reflection function, the equation of line F among Fig. 2 in order to accelerate image processing speed
0Be connected in reference mark C1 and contrast degree C2, and behind two point coordinate of learning reference mark C1 and contrast degree C2, can obtain equation of line F with the linear equation in two unknowns formula
0, wherein more complete explanation will be arranged in the back about choosing of reference mark, and the selected scope of contrast degree C2 be (0～Ctrx, 0) or (0,0～-Ctrx).
In addition, an image can be subdivided into a plurality of pixels, and in picture contrast is handled, pixel is the most basic Flame Image Process unit, place again in the output image on the pixel position corresponding by the brightness value (luminance level) that changes the input pixel, and in this process brightness value how to change be to decide according to aforesaid reflection function.And following explanation for convenience is earlier as follows to the employed formula definition of image processing process at this:
Certain any brightness: Lum=(byte) is (formula 1) (r*0.299+g*0.587+b*0.114);
Always counting of image: count (formula 2) of the * picture traverse of counting of Total=image length; The brightness summation of image:
(formula 3); The average brightness of image: mean=(int) ((Totallum+ (Total/2))/Total) (formula 4); The luminance standard of image is poor:
The brightness histogram slicing center of gravity of image: WeightCenter=∑ (x
i* m
i)/∑ m
i(formula 6); I=0～255 wherein, the brightness value of i ≠ crest maximum, x are the horizontal ordinate of brightness histogram behind the slicing, and m is an ordinate, and i is the brightness value sequence after brightness histogram is removed crest;
See also Fig. 3, the process flow diagram that it is adjusted for picture contrast of the present invention.Picture contrast method of adjustment of the present invention comprises the following steps: at first original image to be constructed brightness histogram (S301), and brightness histogram can be gone out by COMPUTER CALCULATION; Analyze the characteristics of image (S303) of brightness histogram afterwards, promptly choose brightness value and average brightness maximum in the image and judge; Do you judge the situation (S305) that has crest outstanding in the brightness histogram again? judgment mode is whether the brightness value of movement images maximum is much larger than average brightness, the brightness value that is the image maximum deducts average brightness afterwards still greater than a crest judgment value (for default value), and just representing has crest outstanding in the brightness histogram.
And when step S305 is judged as not, then calculate the average brightness (S307) of brightness histogram, can calculate by aforementioned formula 4; Calculate the luminance standard poor (S309) of brightness histogram again, can calculate by aforementioned formula 5; Do you judge image whether bright partially (S311)? it is to be made comparisons by the average brightness of image and a brightness higher limit (being preset as 194 when the brightness of 8 positions), bright greater than brightness higher limit presentation graphs kine bias when average brightness, so the reference mark promptly equals average brightness and deducts luminance standard poor (S317); And when average brightness during less than the brightness higher limit, presentation video does not have bright partially, need further to judge image whether partially dark (S313)? it is to be made comparisons by the average brightness of image and a brightness lower limit (being preset as 64 when the brightness of 8 positions), when average brightness is dark less than brightness lower limit presentation graphs kine bias, the reference mark promptly equals average brightness and adds luminance standard poor (S319); And when average brightness during not less than the brightness lower limit, the brightness of presentation video is moderate, and the reference mark promptly equals average brightness (S315).
And be judged as when being at step S305, represent and occurred the outstanding distribution of crest in the brightness histogram, and outstanding the reflecting of this crest has large-area solid background pattern in the original image, must carry out slicing (clipping) to brightness histogram and handle (S321), and the slicing is here handled to be and removed the interference of background image to image characteristic analysis; Calculate the center of gravity (S323) of slicing brightness histogram afterwards, account form can be obtained by aforementioned formula 6; And make the reference mark equal the x coordinate of center of gravity (S325); Certainly still can further suitably adjust reference mark (S327) according to the image light and shade.
And by abovementioned steps S315, S317, S319, the selected reference mark of getting of one of them of S327 x axle (horizontal ordinate) in rectangular coordinate system all is made as with the coordinate figure of y axle (ordinate) and equates, and can set up gamma table (gammatable) (S329) according to the contrast value (contrast value) that reference mark and institute's desire are adjusted, wherein reference mark and contrast value are that given value and linear equation in two unknowns formula of substitution can be set up a straight line equation as shown in Figure 2 in rectangular coordinate system, and this equation of line is a reflection function that is connected in reference mark and contrast value.And the horizontal ordinate of the rectangular coordinate system of Fig. 2 is represented the input brightness of original image, ordinate is that image is through the adjusted output brightness of contrast, therefore can obtain exporting brightness relatively after will importing the reflection of brightness, can build up contrast in this way and adjust required gamma table via equation of line; At last according to this gamma table to original image degree of comparing adjustment (S331), make the input brightness of each pixel of original image can utilize look-up table (look-up table), from gamma table, find out the brightness value of corresponding output, so can finish picture contrast method of adjustment of the present invention.
Via aforementioned introduction, the present invention can or weaken processing according to the enhancing of characteristics of image degree of comparing, and in order to meet different picture characteristics (as the figure kine bias bright or dark partially or large-area solid background image is arranged), must select one and meet picture characteristics and spend the reference mark of adjusting reference as a comparison via after the suitable judgement.The front of choosing at this reference mark has complete introduction, and after the reference mark determines, can cooperate institute's desire to adjust the input of contrast value, set up equation of line earlier, by equation of line gamma table is set up out in the output brightness that various input brightness are corresponded to again, gamma table is adjusted the contrast power of original image thus.
See also Fig. 4, be the equation of line that is gone out by institute of the present invention construction, wherein C1 is selected reference mark, equation of line F
0The contrast value of (dotted line sign) is 0, and equation of line F
1Contrast value adjust to positive 30.As can be seen from Figure 4, when contrast value C2 is timing, X2＞X1, but-Δ Y2＞-Δ Y1, this equation of line F
1Realized that the big change of pixel intensity is big, the picture contrast adjustment that diminishes that pixel intensity is little.
And with the equation of line F among Fig. 4
1The gamma table that institute's construction goes out after image degree of the comparing adjustment to Fig. 5 A, can obtain the output result of Fig. 5 B.Wherein Fig. 5 A is for having large-area background image, but via picture contrast method of adjustment of the present invention, image in Fig. 5 B is not subjected to background influence and makes the image contrast obviously be partial to a certain numerical value obviously, but presents more level and smooth picture contrast.
Same with the equation of line F among Fig. 4
1The gamma table that institute's construction goes out after image degree of the comparing adjustment to Fig. 6 A, can obtain the output result of Fig. 6 B.Wherein Fig. 6 A is the comparatively image of mean allocation of brightness, but via picture contrast method of adjustment of the present invention, the too bright distortion situation of image does not appear in the image in Fig. 6 B obviously, but it is big to present the big change of pixel intensity, and the little result who diminishes of pixel intensity.
Seeing also Fig. 7, equally is the equation of line that is gone out by institute of the present invention construction, wherein C
1Be selected reference mark, equation of line F
0The contrast value of (dotted line sign) is 0, and equation of line F
2Contrast value adjust to negative 30.As can be seen from Figure 7, when contrast value C2 when negative, X4＞X3, but Δ Y4＜Δ Y3, this equation of line F
2Realized big the diminishing of pixel intensity, the picture contrast adjustment that the change that pixel intensity is little is big is with respect to Fig. 4 cathetus equation F
1Provide the contrast of another kind of aspect to adjust effect.
By picture contrast method of adjustment of the present invention, have following effect:
1, can be according to the characteristics of image that original image presented, adjust the enhancing of contrast relatively or weaken, to reach desirable picture contrast effect.
2,, can shorten the processing time that the image contrast adjusts whereby with the foundation of equation of line as the construction gamma table.
The above, only be the detailed description and the accompanying drawing of the preferable specific embodiment of the present invention one, all closing in the embodiment of the spirit variation similar of the present patent application claim with it, all should be contained in the category of the present invention, any those of ordinary skill in the art in the field of the invention, can think easily and variation or modify and all can be encompassed in claim of the present invention.
Claims (26)
1, a kind of method of adjustment of picture contrast comprises the following steps:
Construct a brightness histogram of an original image;
The characteristics of image of analyzing this brightness histogram is to determine a reference mark;
Capture a contrast value;
In a rectangular coordinate system, set up by this reference mark and a straight line equation that this contrast value connected;
Set up a gamma table according to this equation of line; And
Adjust the contrast of this original image according to this gamma table.
2, picture contrast method of adjustment as claimed in claim 1 is characterized in that this brightness histogram is to be gone out by COMPUTER CALCULATION.
3, picture contrast method of adjustment as claimed in claim 1 is characterized in that the center of gravity that this reference mark is tried to achieve through slicing processing back for this brightness histogram.
4, picture contrast method of adjustment as claimed in claim 1 is characterized in that the average brightness of this reference mark for this brightness histogram.
5, picture contrast method of adjustment as claimed in claim 1 is characterized in that this reference mark subtracts for the average brightness of this brightness histogram or adds the resulting value of a luminance standard difference.
6, picture contrast method of adjustment as claimed in claim 1, it is characterized in that this equation of line for this reference mark and the coordinate figure of this contrast value in this rectangular coordinate system respectively linear equation in two unknowns formula of substitution obtain.
7, picture contrast method of adjustment as claimed in claim 1, it is characterized in that horizontal ordinate in this rectangular coordinate system represents the input brightness of this original image, ordinate represents this original image through the adjusted output brightness of contrast, and the foundation of this gamma table is with the horizontal ordinate that calculates this rectangular coordinate system relatively and the corresponding relation between the ordinate by the reflection of this equation of line.
8, picture contrast method of adjustment as claimed in claim 1 is characterized in that adjusting the contrast of this original image, is that the input brightness with each pixel of this original image utilizes look-up table to find out the brightness value of corresponding output from this gamma table.
9, a kind of picture contrast method of adjustment comprises the following steps:
Construct a brightness histogram of an original image;
Judge whether this brightness histogram has crest outstanding;
When this brightness histogram has crest outstanding, then carry out the slicing processing and obtain a slicing brightness histogram;
Calculate the center of gravity of this slicing brightness histogram and as a reference mark;
Capture a contrast value;
In a rectangular coordinate system, set up by this reference mark and a straight line equation that this contrast value connected;
Set up a gamma table according to this equation of line; And
Adjust the contrast of this original image according to this gamma table.
10, picture contrast method of adjustment as claimed in claim 9, it is characterized in that whether the outstanding difference that is judged as a maximum brightness value and an average brightness in this brightness histogram of this crest surpasses a crest judgment value, has the characteristics of image that crest is given prominence to if then represent this brightness histogram.
11, picture contrast method of adjustment as claimed in claim 9, the account form that it is characterized in that this center of gravity is ∑ (x
i* m
i)/∑ m
i, wherein x is the horizontal ordinate of brightness histogram behind the slicing, and m is an ordinate, and i is the brightness value sequence after brightness histogram is removed crest, i=0～255, and the brightness value of i ≠ crest maximum.
12, picture contrast method of adjustment as claimed in claim 9 is characterized in that this reference mark is the x coordinate figure of this center of gravity at the horizontal ordinate of this rectangular coordinate system and the coordinate figure of ordinate.
13, picture contrast method of adjustment as claimed in claim 9 is characterized in that this slicing is treated to the background image part of removing in this original image.
14, picture contrast method of adjustment as claimed in claim 9, it is characterized in that this equation of line for this reference mark and the coordinate figure of this contrast value in this rectangular coordinate system respectively linear equation in two unknowns formula of substitution obtain.
15, picture contrast method of adjustment as claimed in claim 9, it is characterized in that horizontal ordinate in this rectangular coordinate system represents the input brightness of this original image, ordinate represent this original image through contrast adjust output brightness, and the foundation of this gamma table is with the horizontal ordinate that calculates this rectangular coordinate system relatively and the corresponding relation between the ordinate by the reflection of this equation of line.
16, picture contrast method of adjustment as claimed in claim 9 is characterized in that adjusting the contrast of this original image, is that the input brightness with each pixel of this original image utilizes look-up table, finds out the brightness value of corresponding output from this gamma table.
17, a kind of picture contrast method of adjustment comprises the following steps:
Construct a brightness histogram of an original image;
The average brightness and the luminance standard that calculate this brightness histogram are poor;
Judge whether this average brightness is bright partially or dark partially;
This average brightness and this luminance standard difference are carried out computing and obtain a reference mark;
Capture a contrast value;
In a rectangular coordinate system, set up by this reference mark and a straight line equation that this contrast value connected;
Set up a gamma table according to this equation of line; And
Adjust the contrast of this original image according to this gamma table.
18, picture contrast method of adjustment as claimed in claim 17 is characterized in that this determining step is for comparing this average brightness and a brightness higher limit.
19, picture contrast method of adjustment as claimed in claim 18 is characterized in that this reference mark is poor for this average brightness deducts this luminance standard when this average brightness during greater than this brightness higher limit.
20, picture contrast method of adjustment as claimed in claim 17 is characterized in that this determining step is for comparing this average brightness and a brightness lower limit.
21, picture contrast method of adjustment as claimed in claim 20 is characterized in that this reference mark adds that for this average brightness this luminance standard is poor when this average brightness during less than this brightness lower limit.
22, picture contrast method of adjustment as claimed in claim 17 is characterized in that this determining step is for comparing this average brightness and a brightness higher limit and a brightness lower limit.
23, picture contrast method of adjustment as claimed in claim 22 is characterized in that this reference mark is this average brightness when this average brightness is between this brightness higher limit and this brightness lower limit.
24, picture contrast method of adjustment as claimed in claim 17, it is characterized in that this equation of line for this reference mark and the coordinate figure of this contrast value in this rectangular coordinate system respectively linear equation in two unknowns formula of substitution obtain.
25, picture contrast method of adjustment as claimed in claim 17, it is characterized in that horizontal ordinate in this rectangular coordinate system represents the input brightness of this original image, ordinate represents this original image through the adjusted output brightness of contrast, and the foundation of this gamma table is with the horizontal ordinate that calculates this rectangular coordinate system relatively and the corresponding relation between the ordinate by the reflection of this equation of line.
26, picture contrast method of adjustment as claimed in claim 17 is characterized in that adjusting the contrast of this original image, is that the input brightness with each pixel of this original image utilizes look-up table, finds out the brightness value of corresponding output from this gamma table.
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| Application Number | Priority Date | Filing Date | Title |
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| CNB2004100334808A CN1307598C (en) | 2004-04-12 | 2004-04-12 | How to adjust image contrast |
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| CNB2004100334808A CN1307598C (en) | 2004-04-12 | 2004-04-12 | How to adjust image contrast |
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| CN1307598C CN1307598C (en) | 2007-03-28 |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100388757C (en) * | 2006-02-13 | 2008-05-14 | 友达光电股份有限公司 | Method for enhancing image contrast |
| CN100481903C (en) * | 2006-07-27 | 2009-04-22 | 深圳创维－Rgb电子有限公司 | Adaptive LCD TV display quality adjusting apparatus and method |
| CN100571406C (en) * | 2007-03-19 | 2009-12-16 | 帆宣系统科技股份有限公司 | Image processing apparatus |
| CN100590478C (en) * | 2006-06-12 | 2010-02-17 | 中华映管股份有限公司 | Image contrast correction method and system |
| CN101059951B (en) * | 2006-04-20 | 2010-09-15 | 佳能株式会社 | Image processing apparatus and method |
| CN103347191A (en) * | 2013-06-19 | 2013-10-09 | 深圳市长江力伟股份有限公司 | Video signal processing system based on LCOS display chip |
| CN105844597A (en) * | 2016-03-31 | 2016-08-10 | 深圳市菲森科技有限公司 | Image contrast control method and system |
| CN110800309A (en) * | 2018-08-23 | 2020-02-14 | 深圳市大疆创新科技有限公司 | Image processing method, image processing apparatus, electronic apparatus, and storage medium |
| CN111402147A (en) * | 2020-02-26 | 2020-07-10 | 浙江大华技术股份有限公司 | Video image processing method, video image processing device, computer equipment and storage medium |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE4309878C2 (en) * | 1992-04-06 | 1994-07-21 | Hell Ag Linotype | Method and device for analyzing and correcting the image gradation in image templates |
| TWI231701B (en) * | 2001-06-14 | 2005-04-21 | Matsushita Electric Ind Co Ltd | Automatic tone correction device, automatic tone correction method, and tone correction program recording medium |
| KR100456017B1 (en) * | 2002-02-06 | 2004-11-08 | 삼성전자주식회사 | Contrast enhancement apparatus using histogram matching and method thereof |
-
2004
- 2004-04-12 CN CNB2004100334808A patent/CN1307598C/en not_active Expired - Fee Related
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100388757C (en) * | 2006-02-13 | 2008-05-14 | 友达光电股份有限公司 | Method for enhancing image contrast |
| CN101059951B (en) * | 2006-04-20 | 2010-09-15 | 佳能株式会社 | Image processing apparatus and method |
| CN100590478C (en) * | 2006-06-12 | 2010-02-17 | 中华映管股份有限公司 | Image contrast correction method and system |
| CN100481903C (en) * | 2006-07-27 | 2009-04-22 | 深圳创维－Rgb电子有限公司 | Adaptive LCD TV display quality adjusting apparatus and method |
| CN100571406C (en) * | 2007-03-19 | 2009-12-16 | 帆宣系统科技股份有限公司 | Image processing apparatus |
| CN103347191A (en) * | 2013-06-19 | 2013-10-09 | 深圳市长江力伟股份有限公司 | Video signal processing system based on LCOS display chip |
| CN105844597A (en) * | 2016-03-31 | 2016-08-10 | 深圳市菲森科技有限公司 | Image contrast control method and system |
| CN105844597B (en) * | 2016-03-31 | 2018-12-21 | 深圳市菲森科技有限公司 | The setting contrast method and system of image |
| CN110800309A (en) * | 2018-08-23 | 2020-02-14 | 深圳市大疆创新科技有限公司 | Image processing method, image processing apparatus, electronic apparatus, and storage medium |
| CN110800309B (en) * | 2018-08-23 | 2021-08-27 | 深圳市大疆创新科技有限公司 | Image processing method, image processing apparatus, electronic apparatus, and storage medium |
| CN111402147A (en) * | 2020-02-26 | 2020-07-10 | 浙江大华技术股份有限公司 | Video image processing method, video image processing device, computer equipment and storage medium |
| CN111402147B (en) * | 2020-02-26 | 2023-04-07 | 浙江大华技术股份有限公司 | Video image processing method, video image processing device, computer equipment and storage medium |
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| CN1307598C (en) | 2007-03-28 |
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