CN102507565A - Method for searching reaction color development area of immunochromatographic strip - Google Patents

Abstract

The invention discloses a method for searching a reaction color development area of an immunochromatographic strip. The method is characterized by including the steps: acquiring a total image of the immunochromatographic strip by an image acquisition device; forming a virtual rectangular image frame by using a computer; searching an upper edge line and a lower edge line of a reaction area; measuring the distance between the upper edge line and the lower edge line; acquiring a short central line b parallel to a short edge in the image frame and searching a reaction color development reference line; and searching a test line, acquiring peak data of the test line and determining a color development characteristic area of the test line. The method has the remarkably advantage of capability of accurately, rapidly, reliably and automatically capturing the reaction color development area of the immunochromatographic strip in the image of the immunochromatographic strip.

Description

A kind of immunity-chromatography test strip reaction solution local range search method

Technical field

The invention belongs to based on machine vision immunity-chromatography test strip technical field of measurement and test, concrete is a kind of immunity-chromatography test strip reaction solution local range search method.

Technical background

Modern immunologic assay technology comes from the development of labelling technique.The nineteen forty-one Coons etc. of continuing has founded since the fluorescein labelled antibody technology (fIuoreseent antiboay teeh-nique); Eighties of last century beginning of the sixties at the end of the fifties, Yalaw etc. have founded radiommunoassay (radlol Jnmunoass3y, RIA) technology; South America state in 1966 and French scholar again simultaneously report set up enzyme immunoassay technique (enzyme im-Munoassay; EIA), comprising: the enzyme immunohistochemistry technique, solid-phase enzyme immunoassay is (like ELISA; Westenl blotting) and homogeneous EIA (claim enzyme multiplied immunoassay technique again, EMIT).Another conventional tag technology except that being applied to immuno-electron microscope, is widely used in immunity percolation and immunity-chromatography test for the colloid gold label immunoassay starts from eighties of last century eighties.In addition, report in succession again at present and set up some novel markings immunological techniques, like the rubidium marking immunoassays, nucleic acid marking immunoassays and quantum dot-labeled immunoassay.Some has obtained the experimental technique of these derives from technology using widely in the clinical immunology check, and some still is in research and exploratory stage.Immune chromatograph testing method with advantage such as quick, reliable, easy and simple to handle, that price is low is should develop rapidly aspect clinical diagnosis in recent years, has been widely used in fields such as clinical diagnosis, food safety detection, environment measuring at present.

Principle of work: when drop to be tested was added on the immunochromatography reaction test bar, test solution took collaurum on the test reaction line that is adsorbed with antibody to through the capillary action of absorbing membrane on the immunochromatography reaction test bar.If antibody is corresponding therewith for the antigen in the test solution, then produce specificity association colloid gold and be trapped on the test reaction line, take on a red color or aubergine, the depth of color and the concentration of sample to be tested are corresponding.

Only depend on range estimation that the immune chromatograph testing result is qualitatively judged at present, when very slight color or obscure boundary Chu, range estimation is judged test result with regard to being difficult to, and can not use to quantize to express, and range of application is very limited.Research shows; The concentration significant correlation of the depth of p-wire color and test fluid; Can set up the statistical function relation according to the gray-scale value of p-wire or the concentration of color component and test fluid; Obtain corresponding test fluid concentration through gray-scale value or color component, provide the index of quantification, accomplish the qualitative of test result to the transformation that quantizes.How to obtain gray-scale value or color component, a kind of is to utilize sensors such as photodiode, light transmitting fiber to obtain, and this method has had ripe application on checkout equipments such as urine.But chemical detection such as immunochromatography and urine method has a great difference on principle; Obtain p-wire and can not show a candle to the such colour developing of chemical detection deeply, neatly, evenly; The edge of judgement p-wire need lead to algorithm to be realized, brings very big difficulty for the quantification of test result.A kind of in addition method is through image devices such as CCD, CMOS, through the sensed data of these imaging original papers is handled, obtains the gray-scale value of p-wire, is similar to general Flame Image Process.These two kinds of methods require to have improved manufacturing cost all than higher to the illumination Design of equipment and instrument, manufacturing accuracy and software and hardware facilities, have limited popularization, and existing report as yet.Through Flame Image Process to immunochromatography as a result sentence read result with the method that quantizes to express domestic also do not see openly report for work.

We propose a kind of immunochromatography based on machine vision interpretation method as a result; Obtain the color component of p-wire through image process method; According to digital image processing techniques and apery vision technique; In conjunction with the background modeling technology, weed out the noise in burr, flaw and the image forming course in the biological test paper image; Accurately extract chromogenic line position, immune chromatograph testing district and width; Determine the size of test section chromogenic line colour developing information entropy; And set up the significant correlation funtcional relationship with standard color card; The colour developing depth to the test section chromogenic line is expressed with quantification, has realized that the quantification of immunochromatography interpretation as a result detects.

Wherein, How to obtain and accurately capture immunity-chromatography test strip reaction solution zone in the immunity-chromatography test strip image; Be based on the key of the immunochromatography interpretation as a result technology of machine vision; Only, could guarantee the accuracy of sentence read result carrying out Image Information Processing in the immunity-chromatography test strip reaction solution zone accurately and reliably.

Summary of the invention

The purpose of this invention is to provide a kind of immunity-chromatography test strip reaction solution local range search method, can capture immunity-chromatography test strip reaction solution zone in the immunity-chromatography test strip image accurately and reliably.

For achieving the above object, the present invention explains a kind of immunity-chromatography test strip reaction solution local range search method, and its key is to carry out according to the following steps:

Step 1: utilize image collecting device to gather the global image of immunity-chromatography test strip, and this global image is kept in the computing machine;

Step 2: according to the frames images of the virtual rectangle of color development area information of prior setting, the length of this frames images and wide respectively greater than the length in reaction solution district on the said immunity-chromatography test strip and wide;

Step 3: obtain in the frames images and the parallel long center line in long limit, and search for the coboundary line in reaction solution district to the top of frames images from this long center line;

If in frames images, find the coboundary line; Judge then whether the coboundary line is parallel with long center line; If not parallel, then adjust the angle of said frames images and long center line, make the coboundary line parallel with long center line; And calculate the distance between coboundary line and the long center line, again from the lower limb line of said long center line to the below of frames images search reaction solution district;

If then in frames images, do not find the coboundary line; Then, judge again whether the lower limb line is parallel with long center line, if not parallel earlier from the lower limb line of said long center line to the below of frames images search reaction solution district; Then adjust the angle of frames images and long center line; Make the lower limb line parallel, and calculate the distance between lower limb line and the long center line, again from the coboundary line of said long center line to the top of frames images search reaction solution district with long center line;

Step 4: measure the distance between coboundary line and the lower limb line, the position of adjustment frames images makes long center line be positioned at the centre of coboundary line and lower limb line and parallel with the two;

Step 5: obtain short central line parallel in the frames images with minor face, and from the right-hand search reaction solution reference line of this short central alignment frames images;

If in right-hand frames images, search the reaction solution reference line, then in the specified scope in said reaction solution reference line left side, search for p-wire, and obtain the peak-data of p-wire, confirm the color feature zone of p-wire;

If in right-hand frames images, do not search the reaction solution reference line; Then search for the reaction solution reference line from the left of said short central alignment frames images; After in the left frames images, searching the reaction solution reference line; In the specified scope on said reaction solution reference line right side, search for p-wire again, and obtain the peak-data of p-wire, confirm the color feature zone of p-wire.

In the step 3, the searching method of said coboundary line and reaction solution reference line is: analyzing the regional last lower limb of immunity-chromatography test strip reaction solution can know, one, and the color characteristic of last lower limb changes noticeably, and promptly local edge is apparent in view; Two, the gradient direction of last lower limb almost is and the horizontal direction parallel of image that the gradient direction that promptly is in the pixel at edge is in 90 ± ε.Therefore, the edge detection operator of selecting to be fit to (Sobel, Canny, Prewitt, Roberts etc.) is gone to the edge amplitude and the edge direction angle of detected image.With the Canny edge detection algorithm is example:

?x i-1j-1	x i-1j	x i-1j+1
			?x ij-1	x ij	x ij+1
?x i+1j-1	x ij+1	x i+1j+1

Then the Canny algorithm in the gradient of x direction is:

dx(i，j)＝((x _i+1j+1-x _i+1j)+(x _ij+1-x _ij))/2 (1)

Gradient in the y direction is:

dy(i，j)＝((x _i+1j+1-x _ij+1)+(x _i+1j-x _ij))/2 (2)

Pixel (x, the gradient magnitude of y) locating is:

$d(i,j)=\sqrt{{\mathrm{<figure-callout\; id="2"\; label="dx"\; filenames="HSA00000624825300011.png"\; state="\{\{state\}\}">dx</figure-callout>}}^2+{\mathrm{dy}}^2}---\left(3\right)$

Pixel (x, the gradient direction of y) locating is:

θ(i，j)＝arctan(dy/dx) (4)

According to above-mentioned formula and relevant specificity analysis: concrete processing procedure is following: distinguish compute gradient value and gradient direction values according to formula 3 with 4.According to 90 ± ε restriction of edge direction, each pixel in the image of the overall situation is handled:

$d\_\mathrm{mod}\mathrm{ify}(i,j)=\left\{\begin{array}{cc}0& \mathrm{if}\left(\right|\mathrm{\&theta;}|<10)\\ d& \mathrm{else}\end{array}\right.---\left(5\right)$

Then, according to newly-generated edge magnitude image d_modify, with the edge of image amplitude to the y direction projection, that is:

$f\left(i\right)=\underset{j=0}{\overset{\mathrm{bi}.\mathrm{width}}{\mathrm{\&Sigma;}}}d\_\mathrm{mod}\mathrm{ify}(i,j)---\left(6\right)$

Bi.width in 6 formulas is the width of image, in overall maximizing the y value of using is edge ₁, shielding should the zone then, then seeks time maximal value again, then edge very ₂Ask for edge ₁With edge ₂In maximum one as lower limb, certainly, a minimum boundary value as coboundary.

At last, get the folded intermediate image in edge and turn clockwise 90.According to above-mentioned same step, the latter half of image is sought the left and right edges of reference line after rotation.

In the step 5, said specified scope is 300～500mm.

Remarkable result of the present invention is: a kind of immunity-chromatography test strip reaction solution local range search method is provided, can accurately, have quickly and reliably captured immunity-chromatography test strip reaction solution zone in the immunity-chromatography test strip image automatically.

Description of drawings

Fig. 1 is an immunity-chromatography test strip reaction solution area schematic;

Fig. 2 is a process flow diagram of the present invention.

Embodiment

With regard to specific embodiment the present invention is done further explain below.

As shown in Figure 2: a kind of immunity-chromatography test strip reaction solution local range search method, its key is to carry out according to the following steps:

Step 1: utilize image collecting device to gather the global image of immunity-chromatography test strip, and this global image is kept in the computing machine;

Step 2: according to the frames images A of the virtual rectangle of color development area information of prior setting, the length of this frames images A and wide respectively greater than the length of reaction solution district B on the immunity-chromatography test strip and wide;

Step 3: obtain among the frames images A and the long parallel long center line a in limit, and search for the coboundary line S1 of reaction solution district B to the top of frames images A from this long center line a;

If in frames images A, find coboundary line S1; Judge then whether coboundary line S1 is parallel with long center line a; If not parallel, then adjust the angle of said frames images A and long center line a, make coboundary line S1 parallel with long center line a; And calculate the distance between coboundary line S1 and the long center line a, again from the lower limb line S2 of said long center line a to the below of frames images A search reaction solution district B;

If then in frames images A, do not find coboundary line S1; Then earlier from the lower limb line S2 of said long center line a to the below of frames images A search reaction solution district B; Judge again whether lower limb line S2 is parallel with long center line a; If not parallel, then adjust the angle of frames images A and long center line a, make lower limb line S2 parallel with long center line a; And calculate the distance between lower limb line S2 and the long center line a, again from the coboundary line S1 of said long center line a to the top of frames images A search reaction solution district B;

Step 4: measure the distance between coboundary line S1 and the lower limb line S2, the position of adjustment frames images A makes long center line a be positioned at the centre of coboundary line S1 and lower limb line S2 and parallel with the two;

Step 5: obtain short central line b parallel among the frames images A with minor face, and from the right-hand search reaction solution reference line C of this short central line b to frames images A;

If in right-hand frames images A, search the reaction solution reference line C, then in the specified scope in said reaction solution reference line C left side, search for p-wire D, and obtain the peak-data of p-wire D, confirm the color feature zone of p-wire D;

If in right-hand frames images A, do not search the reaction solution reference line C; Then from the left search reaction solution reference line C of said short central line b to frames images A; After in left frames images A, searching the reaction solution reference line C; In the specified scope on said reaction solution reference line C right side, search for p-wire D again, and obtain the peak-data of p-wire D, confirm the color feature zone of p-wire D.

In the step 3, the searching method of said coboundary line S1 and reaction solution reference line C is: shown in accompanying drawing 1, analyze the last lower limb in immunity-chromatography test strip reaction solution zone and can know, and one, the color characteristic of last lower limb changes noticeably, and promptly local edge is apparent in view; Two, the gradient direction of last lower limb almost is and the horizontal direction parallel of image that the gradient direction that promptly is in the pixel at edge is in 90 ± ε.Therefore, the edge detection operator with selecting to be fit to like Sobel, Canny, Prewitt, Roberts etc., goes to the edge amplitude and the edge direction angle of detected image.With the Canny edge detection algorithm is example:

x i-1j-1	x i-1j	x i-1j+1
			x ij-1	x ij	x ij+1
x i+1j-1	x ij+1	x i+1j+1

Then the Canny algorithm in the gradient of x direction is:

dx(i，j)＝((x _i+1j+1-x _i+1j)+(x _ij+1-x _ij))/2 (1)

Gradient in the y direction is:

dy(i，j)＝((x _i+1j+1-x _ij+1)+(x _i+1j-x _ij))/2 (2)

Pixel (x, the gradient magnitude of y) locating is:

$d(i,j)=\sqrt{{\mathrm{<figure-callout\; id="2"\; label="dx"\; filenames="HSA00000624825300011.png"\; state="\{\{state\}\}">dx</figure-callout>}}^2+{\mathrm{dy}}^2}---\left(3\right)$

Pixel (x, the gradient direction of y) locating is:

θ(i，j)＝arctan(dy/dx) (4)

According to above-mentioned formula and relevant specificity analysis: concrete processing procedure is following: distinguish compute gradient value and gradient direction values according to formula 3 with 4.According to 90 ± ε restriction of edge direction, each pixel in the image of the overall situation is handled:

$d\_\mathrm{mod}\mathrm{ify}(i,j)=\left\{\begin{array}{cc}0& \mathrm{if}\left(\right|\mathrm{\&theta;}|<10)\\ d& \mathrm{else}\end{array}\right.---\left(5\right)$

Then, according to newly-generated edge magnitude image d_modify, with the edge of image amplitude to the y direction projection, that is:

$f\left(i\right)=\underset{j=0}{\overset{\mathrm{bi}.\mathrm{width}}{\mathrm{\&Sigma;}}}d\_\mathrm{mod}\mathrm{ify}(i,j)---\left(6\right)$

(6) bi.width in the formula is the width of image, in overall maximizing the y value of using is edge ₁, shielding should the zone then, then seeks time maximal value again, then edge very ₂Ask for edge ₁With edge ₂In maximum one as lower limb, certainly, a minimum boundary value as coboundary.

At last, get the folded intermediate image in edge and turn clockwise 90.According to above-mentioned same step, the latter half of image is sought the left and right edges of reference line after rotation.

In the step 5, said specified scope is 300～500mm.

Claims (3)

1. immunity-chromatography test strip reaction solution local range search method is characterized in that carrying out according to the following steps:

Step 1: utilize image collecting device to gather the global image of immunity-chromatography test strip, and this global image is kept in the computing machine;

Step 2: according to the frames images (A) of the virtual rectangle of color development area information of prior setting, the length of this frames images (A) and wide respectively greater than the length of reaction solution district (B) on the said immunity-chromatography test strip and wide;

Step 3: obtain in the frames images (A) and the parallel long center line (a) in long limit, and search for the coboundary line (S1) in said reaction solution district (B) to the top of frames images (A) from this long center line (a);

If in frames images (A), find coboundary line (S1); Judge then whether coboundary line (S1) is parallel with long center line (a); If not parallel, then adjust the angle of said frames images (A) and long center line (a), make coboundary line (S1) parallel with long center line (a); And calculate the distance between coboundary line (S1) and the long center line (a), again from the lower limb line (S2) of said long center line (a) to the search reaction solution district, below (B) of frames images (A);

If then in frames images (A), do not find coboundary line (S1); Then earlier from the lower limb line (S2) of said long center line (a) to the search reaction solution district, below (B) of frames images (A); Judge again whether lower limb line (S2) is parallel with long center line (a); If not parallel, then adjust the angle of frames images (A) and long center line (a), make lower limb line (S2) parallel with long center line (a); And calculate the distance between lower limb line (S2) and the long center line (a), again from the coboundary line (S1) of said long center line (a) to the search reaction solution district, top (B) of frames images (A);

Step 4: measure the distance between coboundary line (S1) and the lower limb line (S2), the position of adjustment frames images (A) makes long center line (a) be positioned at the centre of coboundary line (S1) and lower limb line (S2) and parallel with the two;

Step 5: obtain short central line b parallel in the frames images (A) with minor face, and from the right-hand search reaction solution reference line (C) of this short central line b to frames images (A);

If in right-hand frames images (A), search reaction solution reference line (C), then in the specified scope in said reaction solution reference line (C) left side, search for p-wire (D), and obtain the peak-data of p-wire (D), confirm the color feature zone of p-wire (D);

If in right-hand frames images (A), do not search reaction solution reference line (C); Then from the left search reaction solution reference line (C) of said short central line b to frames images (A); After in left frames images (A), searching reaction solution reference line (C); In the specified scope on said reaction solution reference line (C) right side, search for p-wire (D) again, and obtain the peak-data of p-wire (D), confirm the color feature zone of p-wire (D).

2. a kind of immunity-chromatography test strip reaction solution local range search method according to claim 1; It is characterized in that; In the step 3; The searching method of said coboundary line (S1) and reaction solution reference line (C) is: the gradient direction of demarcating the pixel that is in the edge is in 90 ± ε, utilizes the edge amplitude and the edge direction angle of edge detection operator detected image

The gradient of obtaining in the x direction is:

dx(i，j)＝((x _i+1j+1-x _i+1j)+(x _ij+1-x _ij))/2 (1)

Gradient in the y direction is:

dy(i，j)＝((x _i+1j+1-x _ij+1)+(x _i+1j-x _ij))/2 (2)

Pixel (x, the gradient magnitude of y) locating is:

$d(i,j)=\sqrt{{\mathrm{dx}}^2+{\mathrm{dy}}^2}---\left(3\right)$

Pixel (x, the gradient direction of y) locating is:

θ(i，j)＝arctan(dy/dx) (4)

Analyze according to formula (1), (2), (3), (4) and characteristic: concrete processing procedure is following again: according to formula (3) and (4) difference compute gradient value and gradient direction value; According to 90 ± ε restriction of edge direction, each pixel in the image of the overall situation is handled:

$d\_\mathrm{mod}\mathrm{ify}(i,j)=\left\{\begin{array}{cc}0& \mathrm{if}\left(\right|\mathrm{\&theta;}|<10)\\ d& \mathrm{else}\end{array}\right.---\left(5\right)$

Then, according to newly-generated edge magnitude image d_modify, with the edge of image amplitude to the y direction projection, that is:

$f\left(i\right)=\underset{j=0}{\overset{\mathrm{bi}.\mathrm{width}}{\mathrm{\&Sigma;}}}d\_\mathrm{mod}\mathrm{ify}(i,j)---\left(6\right)$

Bi.width in the formula (6) is the width of image, in overall maximizing the y value of using is edge ₁, shielding should the zone then, then seeks time maximal value again, then edge very ₂, ask for edge ₁With edge ₂In maximum one as lower limb, certainly, a minimum boundary value as coboundary;

At last, get the folded intermediate image in edge and turn clockwise 90, according to above-mentioned same step, the latter half of image is sought the left and right edges of reference line after rotation.

3. a kind of immunity-chromatography test strip reaction solution local range search method according to claim 1 is characterized in that in the step 5, said specified scope is 300～500mm.

Images