CN1910615A - System and methods for comparing images with different contrast levels - Google Patents

System and methods for comparing images with different contrast levels Download PDF

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CN1910615A
CN1910615A CN 200580002151 CN200580002151A CN1910615A CN 1910615 A CN1910615 A CN 1910615A CN 200580002151 CN200580002151 CN 200580002151 CN 200580002151 A CN200580002151 A CN 200580002151A CN 1910615 A CN1910615 A CN 1910615A
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digital image
image
gray level
software program
computer software
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CN100573583C (en
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迈克尔·C·哈钦森
迈克尔·D·霍基
马克·A·李
威廉·D·米德
詹姆斯·C·肯尼迪
托马斯·E·里彻斯
迈克尔·J·邓肯
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Boeing Co
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Boeing Co
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Abstract

提供了用来比较具有不同对比度级别的图像的方法和系统。在具有不同对比度级别的图像之间规格化对比度,并且设置亮度。当规格化对比度时,针对具有第一对比度级别的第一数字图像确定灰度电平导数,并且针对具有大于第一对比度级别的第二对比度级别的第二数字图像确定灰度电平导数。确定第一数字图像的灰度电平导数与第二数字图像的灰度电平导数的比率,并且将第一数字图像的灰度电平导数与第二数字图像的灰度电平导数进行均衡。可以手动地、或者例如通过计算排除了背景和文本的平均像素值而自动地设置至少一个图像的亮度。

Figure 200580002151

Methods and systems are provided for comparing images having different contrast levels. Normalizes the contrast between images with different contrast levels, and sets the brightness. When normalizing the contrast, a gray level derivative is determined for a first digital image having a first contrast level, and a gray level derivative is determined for a second digital image having a second contrast level greater than the first contrast level. determining the ratio of the gray level derivative of the first digital image to the gray level derivative of the second digital image and equalizing the gray level derivative of the first digital image with the gray level derivative of the second digital image . The brightness of at least one image may be set manually, or automatically, for example by calculating an average pixel value excluding background and text.

Figure 200580002151

Description

Be used for relatively having the system and method for other image of different contrast level
The cross reference of related application
The application is the non-provisional application of interim (35 USC 119 (e)) application 60/535,358 of submission on January 9th, 2004.
Technical field
The present invention relates generally to a kind of non-destructive evaluation, and relate more specifically to digital radiography.
Background technology
To find defective, for example, such as the hole or the inclusions of bubble or impurity, non-destructive evaluation (NDE) is known for inspection part or material.For example, the x ray is used for the NDE of the manufacture component of system, structure and delivery vehicle (for example boats and ships, land vehicle and such as the aircraft of aircraft and spacecraft) such as piping system.As other more specifically example, because aluminium casting is widely used in aircraft manufacturing, so the inspection cost of the NDE of aluminium casting is represented the quite big number percent of the general inspection cost of aircraft.
This use of x ray is known as " radiography " sometimes.Traditionally, radiography techniques requires checking that the parts of defective are placed between x radiographic source and the silver halide film.Yet traditional silver halide film technical costs is high and time-consuming.
The cost that is associated with traditional silver halide film technology and the reduction of time have been realized by the digital radiography technology.Digital radiography comprises far-ranging technology, and it comprises plate technique, computed radiography art and various technology based on scintillater (scintillator) and digital camera.Transformation, can eliminate and buy film, handle the cost that film and chemical waste disposal are associated from traditional film radiography to digital radiography.In addition, reduction cycle length and robotization by digital radiography provided can realize significant saving.
The main obstruction that the digital radiography realization is used for a large amount of industrial uses is to lack digital reference image.There are a lot of differences in the radiographic images of catching on film with respect to by any radiographic images of catching at present available a lot of digital morphologicals (modalities).As a result, digital radiograph and directly relatively caused between the various digital morphologicals and the different characteristic of the severity level between numeral and the film radiography at the current reference radiography of catching on the film.
Attempted in the industry solving these difference at aluminum casting by converting existing film reference radiography (being used to check the ASTM E155 reference radiography of aluminium and magnesium foundry goods) to digital picture.Yet, can not directly change into the field of digital radiography such as the conventional film reference radiography of ASTM E155.Existing reference radiography is owing to following two main causes have confirmed deficiency: the spatial resolution difference between (1) radiographic film and the digital radiography system; And the difference in dynamic range between (2) film and a lot of digital detector.
About using first shortcoming of existing film reference radiography, the range of size of the granularity of plain radiography film is about 3 microns (μ m) to about 10 μ m, and the scope that is suitable for not utilizing the pixel separation of amplifying the digital radiography system of checking aluminium casting for how much for about 50 μ m to about 139 μ m.As if these differences in resolution do not influence uncontinuity and detect.Yet these differences in resolution influence the classification of the severity level of uncontinuity really.For example, Fig. 1 is with the digitized elongated porosity 1/4 of the pixel separation of 140 μ m " the film radiograph 10 of the third level (plate); Fig. 2 is the film radiograph 20 with the level V of the digitized same train of pixel separation of 50 μ m; And Fig. 3 is only digitized with 50 μ m, identical with film radiograph 10 (Fig. 1) film radiograph 30.By film radiograph 10,20 and 30 more as can be seen, the detector resolution between 50 μ m and the 140 μ m (perhaps, in the case, digitized pixel size) difference causes the skew of approximate two-stage on apparent severity level.
About using second shortcoming of existing film reference radiography, the use that the difference in dynamic range between film and a lot of digital detector shows ASTM E155 reference radiography is not enough for the classification of the severity level of aluminium casting.The wide dynamic range of the digital detector that interrelates with restriction on the number of the recognizable grey level intensity of the mankind makes and is necessary data by the given image of a series of window single-step debugs (stepthrough).At present, this changes brightness (window level) then and carries out to check data by regulate contrast (window width) in series of steps.
When regulating the contrast of the product radiograph that adopts the digital detector acquisition, the shortcoming of this scheme appears.When using high-contrast, uncontinuity looks relatively poor (higher plate number just).When using low contrast, uncontinuity may be not as seen.For example, Fig. 4-6 shows this effect.All images all is from the aluminium 1/4 " single 16 dynamic range digital radiographs of the ASTM E155 part of elongated porosity.Fig. 4 and 6 has the digital radiograph 40 and 60 that same contrast is provided with, and Fig. 5 is in the digital radiograph 50 of higher contrast ratio setting a little.When comparative figures radiograph 40 (Fig. 4) and digital radiograph 50 (Fig. 5),, and, also there is significant difference from identical radiograph even they all are the second level.On the contrary, digital radiograph (Fig. 5) looks and more looks like digital radiograph 60 (Fig. 6).Yet digital radiograph 60 (Fig. 6) is the 7th grade---differ five severity levels (referring to Figure 4 and 5) with the second level.
Owing to the image that can not use known method with respect to parts makes the contrast normalization (normalize) of canonical reference image, so directly relatively be impossible between canonical reference image and the image of component.Therefore, need the exploitation of digital reference image, to catch the saving that digital radiography is provided.Yet, do not have to satisfy needs in the prior art to the method for using the set of number reference picture.
Summary of the invention
Embodiments of the invention provide and have been used for relatively having the method and system of other image of different contrast level.Make contrast normalization between other image of different contrast level having, and brightness is set.Advantageously, embodiments of the invention allow to use the electronic digit reference picture with non-film x radiological survey X system.As a result, use of the present invention can significantly reduce and cost that the time correlation connection is set and the cost that is associated with film, for example is used for the cost of film storage, processing and chemical disposal.And embodiments of the invention can be used for more any digital picture-and be not only the image that obtains by radiography.
In an exemplary application, the electronic digit reference picture allows to use non-film numeral check-up aluminium product foundry goods.When checking the digital radiograph of aluminium casting, digital reference image can be used to substitute current ASTM E155 reference radiography.Advantageously, and use the conventional film radiography of ASTME155 to compare with important mode on statistics, this allows to use the digital radiography of aluminium casting, and need not to change the classification of aluminium casting.
According to embodiments of the invention, relatively has other image of different contrast level.Have normalizing contrast between other image of different contrast level, and brightness is being set.According to an aspect of the present invention, when normalizing contrast, determine derivative of gray level (derivative) at first digital picture, and determine derivative of gray level at second digital picture that has greater than second contrast level of first contrast level with first contrast level.Determine the ratio of the derivative of gray level of the derivative of gray level of first digital picture and second digital picture, and the derivative of gray level of first digital picture and the derivative of gray level of second digital picture are carried out equilibrium (equalize).According to a further aspect in the invention, can be manually or brightness is set automatically.
According to an aspect of the present invention, first digital picture can be a digital reference image, and second digital picture can be by the product digital radiograph of image-forming block.Advantageously, this contrast normalization allows to determine the severity level of uncontinuity---irrelevant with the bit depth of employed digital morphological or digital morphological.Regulate the contrast of reference picture, the contrast of the product image that may generate by the form different with coupling with reference picture.This contrast coupling between reference picture and " the unknown " image allows the meaningful comparison between these two images.
According to each side of the present invention, can determine derivative of gray level with respect to any variable as required.For example, can determine derivative of gray level with respect to thickness.The operator can calculate the grey scale change (for example, on monitor) with respect to the variation in thickness of known materials that is presented at such as in second image of product image.Use approaches or at least two known thickness of drawing together the known materials of the thickness of being paid close attention to into (bracket) are calculated this grey scale change.By calculate such as first image of reference picture with respect to the rate of gray level of thickness and ratio with respect to the rate of gray level of thickness such as second image of product image, standardize.Then, this ratio be multiply by the current image window width such as first image of reference picture, cause the window width of the normalizing contrast between these two images with generation.According to additional aspects of the present invention, can carry out any function of definition derivative of gray level, for example logarithmic function or fitting of a polynomial function.In addition, can use non-homogeneous look-up table.
According to additional aspects of the present invention, can be manually or brightness is set automatically.Can brightness manually be set by regulating window level.Can brightness be set automatically by the average pixel value that background and text have been got rid of in calculating.Then, the mean value with display window is made as the mean value of calculating basically.Alternatively, can be made as the brightest (the highest) pixel value, and lower window edge is made as the darkest (minimum) pixel value, and brightness is set automatically by the upper limit with window.
According to another embodiment of the present invention, provide computer program, it is used for having normalizing contrast between other two images of different contrast level, and is used for being provided with automatically brightness.This computer program advantageously makes processing robotization of the present invention, and promotes to have the comparison of other image of different contrast level.This computer program also promotes to use digital reference image in cost-effective mode in various industry and manufacturing are provided with.
Description of drawings
Fig. 1-the 3rd, the digitized image of the film radiograph of the aluminium inner pore of prior art;
Fig. 4-the 6th, the digital radiograph that the different contrast with aluminium inner pore of prior art is provided with;
Fig. 7 is the process flow diagram according to the exemplary generalized method of the embodiment of the invention;
Fig. 8 is the process flow diagram of the details of method shown in Figure 7;
Fig. 9 is the block scheme that is used for the exemplary host environment of the embodiment of the invention; And
Figure 10-the 13rd is from the screen map of the illustrative computer software program product of the method that realizes Fig. 7 and 8.
Embodiment
As general introduction, embodiments of the invention provide and have been used for relatively having the method and system of other image of different contrast level.Make contrast normalization between other image of different contrast level having, and brightness is set.According to an aspect of the present invention, when making contrast normalization, determine derivative of gray level at first digital picture, and determine derivative of gray level at second digital picture that has greater than second contrast level of first contrast level with first contrast level.Determine the ratio of the derivative of gray level of the derivative of gray level of first digital picture and second digital picture, and the derivative of gray level of first digital picture and the derivative of gray level of second digital picture are carried out equilibrium.According to a further aspect in the invention, can be manually or brightness is set automatically.First digital picture can be a digital reference image, and second digital picture can be the product component image such as digital radiograph.Advantageously, embodiments of the invention allow to use the electronic digit reference picture in the mode of non-film x radiological survey X system (for example digital radiography system).As a result, use of the present invention can significantly reduce and cost that the time correlation connection is set and the cost that is associated with film, for example is used for the cost of film storage, processing and chemical disposal.And embodiments of the invention can be used for relatively having other any digital picture of different contrast level-and be not only the image that obtains by radiography.
The present invention may be embodied as method, computer software program product and system.To set forth the details of the non-limiting example of each embodiment of the present invention below.
With reference to figure 7, be used for relatively having the generalized method 100 of other image of different contrast level in piece 102 beginnings.At piece 103, between image, make contrast normalization.At piece 104, determine derivative of gray level at first digital picture such as reference picture with first contrast level.Can carry out any function of definition derivative of gray level, for example logarithmic function or fitting of a polynomial function.As non-limiting example, reference picture can be a digital reference image, the ASTM E2422 reference picture that is for example proposed etc.Can be according to the needs of concrete application, and determine derivative of gray level with respect to any variable.For example, can determine derivative of gray level with respect to thickness.In application, can determine derivative with respect to thickness such as but not limited to radiography.As other example, employed variable can represent to contrast the mapping variable such as the palette of gray scale when determining derivative.For example, image can represent temperature, highly, density or at the mapping of required any other variable of concrete application.In these images, with respect to temperature, highly, density or any variable of using in concrete the application determine the derivative of gray scale.
At piece 106, determine derivative of gray level at second digital picture that has greater than second contrast level of first contrast level, wherein second digital picture is such as but not limited to by the digital picture of any product component of imaging.Yet second digital picture can be the digital picture at the required any kind of application-specific.As in piece 104, can carry out any function of definition derivative of gray level, for example logarithmic function or fitting of a polynomial function.In one exemplary embodiment, according to the needs of the concrete application digital morphological by any kind product component is carried out digital imagery.As non-limiting example, suitable digital morphological comprises digital radiography.Yet the digital radiography that is adopted can comprise any in the far-ranging technology, and it comprises plate technique, computed radiography art and various technology based on scintillater and digital camera.As in piece 104, can be according to the needs of concrete application and determine derivative of gray level with respect to any variable.In the example of the digital morphological of discussing at piece 106, can determine derivative of gray level with respect to thickness.Yet, as in piece 104, in other is used, with respect to temperature, highly, density or any variable of using in concrete the application determine the derivative of gray scale.
At piece 108, determine the ratio of the derivative of gray level of the derivative of gray level of first digital picture and second digital picture.Can carry out any function of definition, for example logarithmic function or fitting of a polynomial function with respect to the derivative of gray level of thickness.At piece 110, the derivative of gray level of first digital picture and the derivative of gray level of second digital picture are carried out equilibrium.In a non-limiting example, carry out equilibrium by determining that window shines upon.The window mapping is applicable to logarithm gray scale and linear gray scales.Alternatively, can shine upon by rule of thumb predetermined look-up table such as non-homogeneous look-up table.
After piece 103 has been standardized contrast between first digital picture and second digital picture, may be desirably in the operator carry out between the image relatively before regulate the brightness of at least one image.Regulate brightness and can help operator's movement images.Typically, the brightness (first digital picture in the case) that has than the image of low contrast is regulated in expectation.
At piece 111, manually or automatically regulate brightness.Can come with software manual adjustments brightness setting by regulating window level.
Alternatively, at piece 111, can regulate the brightness of arbitrary image or two images as required and automatically.For example, the upper limit of window can be made as the brightest (the highest) pixel value, and lower window edge can be made as the darkest (minimum) pixel value.Alternatively, can brightness be set automatically by the average pixel value that background and text have been got rid of in calculating, and the mean value of the display window average pixel value that is set to calculate.The pixel value of background or text pixel value be can be known as by eliminating, background and text got rid of.Typically, be in the extreme pixel value (just, 0 and 2 of minimum and most significant end of the data area of n bit image n) be used for background or text.For example, in sixteen bit image, background often is made as zero (0) or 65,535, and text often is made as 65,535 or zero (0).This scheme has guaranteed that text is clear and legible with respect to background, and is provided with irrelevant with employed contrast and brightness.Then, brightness is set, makes the mean value of display window be set to the average pixel value of after having got rid of text and background, having calculated.Brightness need not accurately to be made as the average pixel value of calculating.Brightness can be approx or is made as the average pixel value of calculating basically.For example, the mean value of display window can be arranged near positive and negative (plus-or-minus) scope half of display window width, perhaps can it be set according to the needs of concrete application.
Normalizing contrast and being provided with as required under the situation of brightness between first and second images, the operator can compare between first and second images.Method 100 finishes at piece 112.
With reference now to Fig. 8,, method 200 realizes a preferred embodiment of generalized methods 100 (Fig. 7), and it is used for relatively having first image such as the reference picture of first contrast level and has greater than second image of second contrast level of first contrast level as by the product digital picture of image-forming block.Method 200 is in piece 202 beginnings.At piece 203, normalizing contrast between image.At piece 204, determine at reference picture to change with respect to grey level such as the variation of another variable of thickness with first contrast level.As top discuss at piece 104 (Fig. 7), can be according to the needs of concrete application and choice variable.Because the gray-value variation with respect to such as the variation of the variable of thickness in the reference picture all keeps identical for each reference picture, therefore this value or function are advantageously calculated once, and all are cited for each normalization of this reference picture of use.The reference picture of being discussed at piece 104 (Fig. 7) above being similar to, reference picture can include but not limited to ASTM E2422 reference picture etc.
At piece 206,, and determine to change with respect to grey level such as the variation of the variable of thickness at second image (for example by the digital picture of image-forming block) that has greater than second contrast level of first contrast level.As top discuss at piece 106 (Fig. 7), can be according to the needs of concrete application and choice variable.Use approaches or draws together at least two known thickness into the known materials of the thickness of being paid close attention to, calculates grey level and changes.As non-limiting example, can be aluminium casting by image-forming block.Yet according to the needs of concrete application, these parts can comprise the parts of any kind of making by any manufacturing technology.
At piece 208, determine that the grey level with respect to variable change of reference picture changes and the ratio that is changed by the grey level with respect to variable change of image-forming block.At piece 210, the grey level with respect to variable change of reference picture is changed and be multiply by by the ratio that the grey level with respect to variable change of image-forming block changes the window width of reference picture.To have window width than other image of low contrast level and multiply by this ratio and determine the window mapping, and change to change and carry out equilibrium with grey level with other image of higher contrast level will have grey level than other image of low contrast level.As a result, normalizing contrast at reference picture and between by the digital picture of image-forming block.This allows the operator relatively by the digital picture of image-forming block and reference picture, thereby promotes may be present in by the classification of the severity of any defective in the image-forming block such as hole.
As top discuss at piece 111 (Fig. 7), in some cases, may be desirably in the brightness setting that the operator regulates at least one image before comparing.Typically, may expect to regulate the brightness setting that has than other image of low contrast level.At piece 211,, manually or automatically regulate the brightness setting as required with in the described mode of piece 111 (Fig. 7).
Normalizing contrast and being provided with as required under the situation of brightness between first and second images, the operator can compare between first and second images.Method 200 finishes at piece 212.
With reference now to Fig. 9,, can usage example hosted environment 300 resident (host) be used between digital picture normalizing contrast and/or regulates the brightness setting of digital picture and/or the system 302 of comparative figures image.System 302 advantageously as required and manner of execution 100 (Fig. 7) or method 200 (Fig. 8).In one exemplary embodiment, system 302 comprises computing machine 304, for example personal computer, desk-top computer, large scale computer, workstation, laptop computer, palmtop computer, personal digital assistant etc.System 302 also comprises the storage medium 306 of storing digital reference image.Storage medium 306 can comprise any acceptable storage medium, for example internal hard disk drive, external fixed disk drive, optical disk storage apparatus, CD-ROM, DVD, floppy disk etc.
In an exemplary environments, generate the digital radiograph of parts, and digital radiograph is offered system 302.In known manner, x radiographic source 308 provides the x ray 310 that parts 312 is carried out imaging.The image of digital detector 314 detection parts 312.As mentioned above, the digital radiography that is adopted can comprise any in the far-ranging technology, and it comprises plate technique, computed radiography art and various technology based on scintillater and digital camera.Digital detector 314 will be offered computing machine 304 by the digital picture of image-forming block 312.Yet the digital picture that offers computing machine 304 can be the digital picture at the required any kind of concrete application.
With reference now to Figure 10-13,, a kind of computer software program product is carried out by computing machine 304 (Fig. 9), with manner of execution 100 or 200 (Fig. 7 and 8).With reference to Figure 10, show two screens 400 and 410 side by side.As required, screen 400 and 410 can be presented on identical monitor or the independent monitor.Screen 400 shows reference picture.As non-limiting example, reference picture is used for the gas hole defect in 1/4 inch thick aluminium.Reference picture comprises the step (step wedge) that the severity that is used for defective carries out eight grades of classification and has the thickness of 0.150 inch, 0.200 inch, 0.250 inch, 0.300 inch, 0.400 inch and 0.500 inch.Screen 410 shows by the digital radiograph of image-forming block.As non-limiting example, shown in parts are aluminum cast angle bracket.Comprised two areas of porosity defects by image-forming block, it shows as the interior foam or the bubble domain of gray area of these parts.To these areas of porosity defects and the reference picture in the digital radiograph be compared.
Pull-down menu under " digital radiography " comprises " DR line chart statistics ", " DR line chart ", " pixel size ", " contrast calibration 1/4 " and " contrast calibration 3/4 " option." DR line chart statistics " and " DR line chart " option be selection wire and generation line chart separately." pixel size " option allows the input pixel size, and allows to carry out the point-to-point measurement." contrast calibration 1/4 " selects the thickness such as but not limited to the material of aluminium between will be at the 0-1/2 inch of its normalizing contrast.In addition, the thickness at these grades shown in the reference picture is set as 1/4 inch.Similarly, " contrast calibration 3/4 " selects the thickness such as but not limited to the material of aluminium between will be at the 1/2-2 inch of its normalizing contrast.In addition, the thickness at these grades shown in the reference picture is set as 3/4 inch.Parts in this example on thickness less than 1/2 inch, thereby select " contrast calibration 1/4 ".
When selecting " contrast calibration 1/4 ", generate the screen 420 and 430 of Figure 11.For example by with click with drag, click " the 1st step " radio button and draw together into thickness and draw frame with the 1st step of screen 430.Analyze the pixel of being painted in the frame and be used for statistics.The statistics of being paid close attention to be at 0.150 inch the 1st the step thickness the average gray level value.This is because the grey level value that the 1st step thickness of this average gray level value and 0.150 inch will be used for calculating with respect to thickness changes or grey level value derivative.
Click " the 2nd step " radio button and draw together into thickness, and generate the screen 440 and 450 of Figure 12 to select next.In the 2nd step thickness of screen 450, draw frame.The pixel of analyzing in institute's frame of painting is used for adding up.Equally, the statistics of being paid close attention to be at 0.200 inch the 2nd the step thickness the average gray level value.
Click " calibration " button, and generate the screen 460 and 470 of Figure 13.Screen 460 expression reference pictures, and screen 470 expressions are by the digital radiograph of image-forming block.When click " calibration " button, change at the screen 460 and the average gray level in the 1st step of 470 calculating and the 2nd step respectively, and go on foot thickness and the 2nd variation in thickness that goes on foot between the thickness divided by the 1st at screen 460 and 470.By the result of screen 460 is determined ratio divided by the result of screen 470.At as described in the method 200 (Fig. 8), this ratio be multiply by the window width of reference picture (that is, screen 460) as top.As a result, the contrast by the reference picture shown in contrast between the digital radiograph of image-forming block and the screen 460 shown in the screen 470 is standardized.By relatively eight grades shown in the screen 440 (Figure 12) and eight grades shown in the screen 460, feel this contrast normalization significantly.Shown in the non-limiting example, the hole defective shown in the screen 470 is with suitable in the hole defective shown in the 3rd level of the reference picture shown in the screen 460 or the 4th grade.Under the situation that does not have the contrast normalization between digital radiograph and the reference picture, just can not carry out such comparison.For example, temporarily get back to Figure 12, any in eight grades shown in the reference picture of digital radiograph shown in the screen 450 and screen 440 relatively will be insignificant.Advantageously, as the result of the contrast normalization between digital radiograph and the reference picture, can carry out the direct comparison between digital radiograph and the reference picture now.
Typically, computer program instructions can be loaded on computing machine or other programmable device, to produce machine, so that the instruction of carrying out on computing machine or other programmable device is configured for being implemented in the device of the function of appointment in process flow diagram or screen segment or the step.These computer program instructions can also be stored in can vectoring computer or the computer-readable memory of other programmable device with ad hoc fashion work in produce and comprise the product that is implemented in the command device of the function of appointment in process flow diagram or screen segment or the step so that be stored in instruction in the computer-readable memory.These computer program instructions can also be loaded on computing machine or other programmable device, so that on computing machine or other programmable device, carry out the sequence of operations step, thereby produce computer implemented processing, on computing machine or other programmable device so that the instruction of carrying out is provided for being implemented in the step of the function of appointment in process flow diagram or screen segment or the step.
Thereby each piece of process flow diagram or screen map or step support are used to the combination carrying out the device of appointed function and be used to carry out the program instruction means of appointed function.The combination that it is also understood that the piece of each piece of process flow diagram or screen map or step and process flow diagram or screen map or step can be by carrying out realizing based on the computer system of specialized hardware or the combination of specialized hardware and computer instruction of appointed function or step.
Though illustrate and described the preferred embodiments of the present invention as mentioned above, under the situation that does not break away from the spirit and scope of the present invention, can much change.Thereby scope of the present invention is not subject to the disclosure of preferred embodiment.On the contrary, should determine the present invention with reference to claims fully.

Claims (37)

1.一种比较数字图像的方法,该方法包括:1. A method of comparing digital images, the method comprising: 在具有第一对比度级别的第一数字图像和具有大于第一对比度级别的第二对比度级别的第二数字图像之间规格化对比度;以及normalizing the contrast between a first digital image having a first contrast level and a second digital image having a second contrast level greater than the first contrast level; and 调节第一和第二数字图像中的至少一个的亮度设置。A brightness setting of at least one of the first and second digital images is adjusted. 2.如权利要求1所述的方法,其中规格化对比度的步骤包括:2. The method of claim 1, wherein the step of normalizing the contrast comprises: 确定第一数字图像的灰度电平导数;determining a gray level derivative of the first digital image; 确定第二数字图像的灰度电平导数;determining a gray level derivative of the second digital image; 确定第一数字图像的灰度电平导数与第二数字图像的灰度电平导数的比率;以及determining the ratio of the gray level derivative of the first digital image to the gray level derivative of the second digital image; and 将第一数字图像的灰度电平导数与第二数字图像的灰度电平导数进行均衡。The gray level derivatives of the first digital image are equalized with the gray level derivatives of the second digital image. 3.如权利要求1所述的方法,其中以手动和自动中的一种执行调节亮度设置。3. The method of claim 1, wherein adjusting the brightness setting is performed one of manually and automatically. 4.如权利要求3所述的方法,其中自动调节亮度设置的步骤包括:4. The method of claim 3, wherein the step of automatically adjusting the brightness setting comprises: 排除图像窗口中的文本和背景;Exclude text and background in image windows; 针对图像窗口计算排除了文本和背景的平均像素值;以及Compute an average pixel value for the image window excluding text and background; and 将图像窗口的平均像素值设为算出的平均像素值。Set the average pixel value of the image window to the calculated average pixel value. 5.一种用于比较数字图像的系统,该系统包括:5. A system for comparing digital images, the system comprising: 存储装置,被配置成至少存储具有第一对比度级别的第一数字图像;a storage device configured to store at least a first digital image having a first contrast level; 输入接口,被配置成至少输入具有大于第一对比度级别的第二对比度级别的第二数字图像;an input interface configured to input at least a second digital image having a second contrast level greater than the first contrast level; 处理器,包括:Processor, including: 第一组件,被配置成在第一数字图像和第二数字图像之间规格化对比度;以及a first component configured to normalize contrast between the first digital image and the second digital image; and 第二组件,被配置成调节第一和第二数字图像中的至少一个的亮度设置。A second component configured to adjust a brightness setting of at least one of the first and second digital images. 6.如权利要求5所述的系统,其中该第一组件还被配置成:6. The system of claim 5, wherein the first component is further configured to: 确定第一数字图像的灰度电平导数;determining a gray level derivative of the first digital image; 确定第二数字图像的灰度电平导数;determining a gray level derivative of the second digital image; 确定第一数字图像的灰度电平导数与第二数字图像的灰度电平导数的比率;以及determining the ratio of the gray level derivative of the first digital image to the gray level derivative of the second digital image; and 将第一数字图像的灰度电平导数与第二数字图像的灰度电平导数进行均衡。The gray level derivatives of the first digital image are equalized with the gray level derivatives of the second digital image. 7.如权利要求5所述的系统,其中该第二组件还被配置成通过以下操作来自动调节亮度设置:7. The system of claim 5, wherein the second component is further configured to automatically adjust the brightness setting by: 排除图像窗口中的文本和背景;Exclude text and background in image windows; 针对图像窗口计算排除了文本和背景的平均像素值;以及Compute an average pixel value for the image window excluding text and background; and 将图像窗口的平均像素值设为算出的平均像素值。Set the average pixel value of the image window to the calculated average pixel value. 8.一种用于比较数字图像的计算机软件程序产品,该计算机软件程序产品包括:8. A computer software program product for comparing digital images, the computer software program product comprising: 第一计算机软件程序代码装置,用于在具有第一对比度级别的第一数字图像和具有大于第一对比度级别的第二对比度级别的第二数字图像之间规格化对比度;以及first computer software program code means for normalizing the contrast between a first digital image having a first contrast level and a second digital image having a second contrast level greater than the first contrast level; and 第二计算机软件程序代码装置,用于调节第一和第二数字图像中的至少一个的亮度设置。Second computer software program code means for adjusting a brightness setting of at least one of the first and second digital images. 9.如权利要求8所述的计算机软件程序产品,其中该第一计算机软件程序代码装置包括:9. The computer software program product of claim 8, wherein the first computer software program code means comprises: 第三计算机软件程序代码装置,用于确定第一数字图像的灰度电平导数;third computer software program code means for determining a gray level derivative of the first digital image; 第四计算机软件程序代码装置,用于确定第二数字图像的灰度电平导数;fourth computer software program code means for determining a gray level derivative of the second digital image; 第五计算机软件程序代码装置,用于确定第一数字图像的灰度电平导数与第二数字图像的灰度电平导数的比率;以及fifth computer software program code means for determining a ratio of a gray level derivative of the first digital image to a gray level derivative of the second digital image; and 第六计算机软件程序代码装置,用于将第一数字图像的灰度电平导数与第二数字图像的灰度电平导数进行均衡。Sixth computer software program code means for equalizing the gray level derivative of the first digital image with the gray level derivative of the second digital image. 10.如权利要求8所述的计算机软件程序产品,其中该第二计算机软件程序代码装置包括:10. The computer software program product of claim 8, wherein the second computer software program code means comprises: 第七计算机软件程序代码装置,用于排除图像窗口中的文本和背景;A seventh computer software program code means for excluding text and background in the image window; 第八计算机软件程序代码装置,用于针对图像窗口计算排除了文本和背景的平均像素值;以及eighth computer software program code means for calculating an average pixel value excluding text and background for the image window; and 第九计算机软件程序代码装置,用于将图像窗口的平均像素值设为算出的平均像素值。The ninth computer software program code means is used for setting the average pixel value of the image window as the calculated average pixel value. 11.一种在数字图像之间规格化对比度的方法,该方法包括:11. A method of normalizing contrast between digital images, the method comprising: 确定具有第一对比度级别的第一数字图像的灰度电平导数;determining a gray level derivative of a first digital image having a first contrast level; 确定具有大于第一对比度级别的第二对比度级别的第二数字图像的灰度电平导数;determining a gray level derivative of a second digital image having a second contrast level greater than the first contrast level; 确定第一数字图像的灰度电平导数与第二数字图像的灰度电平导数的比率;以及determining the ratio of the gray level derivative of the first digital image to the gray level derivative of the second digital image; and 将第一数字图像的灰度电平导数与第二数字图像的灰度电平导数进行均衡。The gray level derivatives of the first digital image are equalized with the gray level derivatives of the second digital image. 12.如权利要求11所述的方法,其中该均衡步骤包括确定窗口映射。12. The method of claim 11, wherein the equalizing step includes determining a window map. 13.如权利要求12所述的方法,其中确定窗口映射的步骤包括将第一数字图像的灰度电平导数与第二数字图像的灰度电平导数的比率乘以第一数字图像的窗口宽度。13. The method of claim 12, wherein the step of determining the window mapping comprises multiplying the ratio of the gray level derivative of the first digital image to the gray level derivative of the second digital image by the window of the first digital image width. 14.如权利要求11所述的方法,其中该均衡步骤包括访问查找表。14. The method of claim 11, wherein the equalizing step includes accessing a look-up table. 15.如权利要求14所述的方法,其中该查找表是非线性的。15. The method of claim 14, wherein the look-up table is non-linear. 16.如权利要求11所述的方法,其中确定导数的步骤确定定义导数的函数,该函数包括对数函数和多项式拟合函数中的一个。16. The method of claim 11, wherein the step of determining the derivative determines a function defining the derivative, the function comprising one of a logarithmic function and a polynomial fitting function. 17.如权利要求11所述的方法,其中确定导数的步骤确定相对于厚度的导数。17. The method of claim 11, wherein the step of determining a derivative determines a derivative with respect to thickness. 18.一种用于在数字图像之间规格化对比度的系统,该系统包括:18. A system for normalizing contrast between digital images, the system comprising: 存储装置,被配置成至少存储具有第一对比度级别的第一数字图像;a storage device configured to store at least a first digital image having a first contrast level; 输入接口,被配置成至少输入具有大于第一对比度级别的第二对比度级别的第二数字图像;an input interface configured to input at least a second digital image having a second contrast level greater than the first contrast level; 处理器,包括:Processor, including: 第一组件,被配置成确定第一数字图像的灰度电平导数;a first component configured to determine a gray level derivative of the first digital image; 第二组件,被配置成确定第二数字图像的灰度电平导数;a second component configured to determine a gray level derivative of the second digital image; 第三组件,被配置成确定第一数字图像的灰度电平导数与第二数字图像的灰度电平导数的比率;以及a third component configured to determine a ratio of a gray level derivative of the first digital image to a gray level derivative of the second digital image; and 第四组件,被配置成将第一数字图像的灰度电平导数与第二数字图像的灰度电平导数进行均衡。A fourth component configured to equalize the gray level derivatives of the first digital image with the gray level derivatives of the second digital image. 19.如权利要求18所述的系统,其中该第四组件还被配置成确定窗口映射。19. The system of claim 18, wherein the fourth component is further configured to determine window mapping. 20.如权利要求19所述的系统,其中该第四组件还被配置成将第一数字图像的灰度电平导数与第二数字图像的灰度电平导数的比率乘以第一数字图像的窗口宽度。20. The system of claim 19, wherein the fourth component is further configured to multiply the ratio of the gray level derivative of the first digital image to the gray level derivative of the second digital image by the first digital image the window width. 21.如权利要求18所述的系统,其中该第四组件还被配置成访问查找表。21. The system of claim 18, wherein the fourth component is further configured to access a lookup table. 22.如权利要求21所述的系统,其中该查找表是非线性的。22. The system of claim 21, wherein the look-up table is non-linear. 23.如权利要求18所述的系统,其中所述第一和第二组件还被配置成确定定义导数的函数,该函数包括对数函数和多项式拟合函数中的一个。23. The system of claim 18, wherein the first and second components are further configured to determine a function defining a derivative, the function comprising one of a logarithmic function and a polynomial fitting function. 24.如权利要求18所述的系统,其中所述第一和第二组件还被配置成确定相对于厚度的导数。24. The system of claim 18, wherein the first and second components are further configured to determine a derivative with respect to thickness. 25.一种用于在数字图像之间规格化对比度的计算机软件程序产品,该计算机软件程序产品包括:25. A computer software program product for normalizing contrast between digital images, the computer software program product comprising: 第一计算机软件程序代码装置,用于确定具有第一对比度级别的第一数字图像的灰度电平导数;first computer software program code means for determining a gray level derivative of a first digital image having a first contrast level; 第二计算机软件程序代码装置,用于确定具有大于第一对比度级别的第二对比度级别的第二数字图像的灰度电平导数;second computer software program code means for determining a gray level derivative of a second digital image having a second contrast level greater than the first contrast level; 第三计算机软件程序代码装置,用于确定第一数字图像的灰度电平导数与第二数字图像的灰度电平导数的比率;以及third computer software program code means for determining a ratio of a gray level derivative of the first digital image to a gray level derivative of the second digital image; and 第四计算机软件程序代码装置,用于将第一数字图像的灰度电平导数与第二数字图像的灰度电平导数进行均衡。Fourth computer software program code means for equalizing the gray level derivative of the first digital image with the gray level derivative of the second digital image. 26.如权利要求25所述的计算机软件程序产品,其中该第四计算机软件程序代码装置还被配置成确定窗口映射。26. The computer software program product of claim 25, wherein the fourth computer software program code means is further configured to determine window mapping. 27.如权利要求26所述的计算机软件程序产品,其中该第四计算机软件程序代码装置被配置成通过将第一数字图像的灰度电平导数与第二数字图像的灰度电平导数的比率乘以第一数字图像的窗口宽度来确定窗口映射。27. The computer software program product as claimed in claim 26, wherein the fourth computer software program code means is configured to convert the gray level derivative of the first digital image to the gray level derivative of the second digital image The ratio is multiplied by the window width of the first digital image to determine the window mapping. 28.如权利要求25所述的计算机软件程序产品,其中该第四计算机软件程序代码装置还被配置成访问查找表。28. The computer software program product of claim 25, wherein the fourth computer software program code means is further configured to access a look-up table. 29.如权利要求28所述的计算机软件程序产品,其中该查找表是非线性的。29. The computer software program product of claim 28, wherein the look-up table is non-linear. 30.如权利要求25所述的计算机软件程序产品,其中所述第一和第二计算机软件程序代码装置还被配置成确定定义导数的函数,该函数包括对数函数和多项式拟合函数中的一个。30. The computer software program product according to claim 25, wherein said first and second computer software program code means are further configured to determine a function defining a derivative, the function comprising a logarithmic function and a polynomial fitting function one. 31.如权利要求25所述的计算机软件程序产品,其中所述第一和第二计算机软件程序代码装置还被配置成确定相对于厚度的导数。31. The computer software program product of claim 25, wherein the first and second computer software program code means are further configured to determine a derivative with respect to thickness. 32.一种自动调节数字图像的亮度设置的方法,该方法包括:32. A method of automatically adjusting a brightness setting of a digital image, the method comprising: 输入图像;input image; 排除图像中的文本和背景;Exclude text and backgrounds from images; 针对图像计算排除了文本和背景的平均像素值;以及Compute average pixel values for images excluding text and background; and 将亮度设置基本上设为算出的平均像素值。Basically set the brightness setting to the calculated average pixel value. 33.如权利要求32所述的方法,其中:33. The method of claim 32, wherein: 该图像是n位图像;The image is an n-bit image; 该图像中的背景具有位于n位图像的数据范围的最低和最高端中的一个的像素值;以及the background in the image has pixel values at one of the lowest and highest ends of the data range of the n-bit image; and 该图像中的文本具有位于n位图像的数据范围的最高和最低端中的另一个的像素值。The text in this image has a pixel value at the other of the highest and lowest ends of the data range of the n-bit image. 34.一种用于自动调节数字图像的亮度设置的系统,该系统包括:34. A system for automatically adjusting a brightness setting of a digital image, the system comprising: 输入接口,被配置成输入图像;以及an input interface configured to input an image; and 处理器,包括:Processor, including: 第一组件,被配置成排除图像中的文本和背景;a first component configured to exclude text and background in the image; 第二组件,被配置成针对图像计算排除了文本和背景的平均像素值;以及a second component configured to calculate, for the image, an average pixel value excluding text and background; and 第三组件,被配置成将亮度设置基本上设为算出的平均像素值。A third component, configured to set the brightness setting substantially to the calculated average pixel value. 35.如权利要求34所述的系统,其中:35. The system of claim 34, wherein: 该图像是n位图像;The image is an n-bit image; 该图像中的背景具有位于n位图像的数据范围的最低和最高端中的一个的像素值;以及the background in the image has pixel values at one of the lowest and highest ends of the data range of the n-bit image; and 该图像中的文本具有位于n位图像的数据范围的最高和最低端中的另一个的像素值。The text in this image has a pixel value at the other of the highest and lowest ends of the data range of the n-bit image. 36.一种用于自动调节数字图像的亮度设置的计算机软件程序产品,该计算机软件程序产品包括:36. A computer software program product for automatically adjusting the brightness setting of a digital image, the computer software program product comprising: 第一计算机软件程序代码装置,用于排除图像中的文本和背景;first computer software program code means for excluding text and background in the image; 第二计算机软件程序代码装置,用于针对图像计算排除了文本和背景的平均像素值;以及a second computer software program code means for calculating an average pixel value excluding text and background for the image; and 第三计算机软件程序代码装置,用于将亮度设置基本上设为算出的平均像素值。Third computer software program code means for setting the brightness setting substantially to the calculated average pixel value. 37.如权利要求36所述的计算机软件程序产品,其中:37. The computer software program product of claim 36, wherein: 该图像是n位图像;The image is an n-bit image; 该图像中的背景具有位于n位图像的数据范围的最低和最高端中的一个的像素值;以及the background in the image has pixel values at one of the lowest and highest ends of the data range of the n-bit image; and 该图像中的文本具有位于n位图像的数据范围的最高和最低端中的另一个的像素值。The text in this image has a pixel value at the other of the highest and lowest ends of the data range of the n-bit image.
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CN103544931A (en) * 2013-10-12 2014-01-29 Tcl集团股份有限公司 Character generating method and device and application terminal
CN103842847A (en) * 2012-09-28 2014-06-04 株式会社东芝 Nuclear medicine diagnostic device, image diagnostic device, and image processing method
CN106485652A (en) * 2016-10-12 2017-03-08 青岛海信电器股份有限公司 Setting contrast method and device

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* Cited by examiner, † Cited by third party
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CN103842847A (en) * 2012-09-28 2014-06-04 株式会社东芝 Nuclear medicine diagnostic device, image diagnostic device, and image processing method
CN103842847B (en) * 2012-09-28 2016-04-27 株式会社东芝 Nuclear medicine diagnostic apparatus, image diagnosing system and image processing method
CN103544931A (en) * 2013-10-12 2014-01-29 Tcl集团股份有限公司 Character generating method and device and application terminal
CN106485652A (en) * 2016-10-12 2017-03-08 青岛海信电器股份有限公司 Setting contrast method and device

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