KR20010074602A - Method for handling an image of dna chip - Google Patents

Abstract

PURPOSE: Provided is an imaging method of DNA chip, which in particular, clearly images DNA chip of a human tissue sample to diagnose human diseases by removing unnecessary dots from the screen. CONSTITUTION: An imaging method comprises the step of: inputting the detection image of DNA chip with plural pixels; producing the virtual mask image having transmission windows which correspond to the plural pixels of the detection image; and indicating only the pixels of the detection image through the transmission window of the virtual mask by overlapping the virtual image and the detection image. Preferably, after overlapping images, the imaging method comprises the step of comparing pixel level of the detection image indicated through the transmission window with pre-established critical value. Subsequently, low pass filtering process that reduces the pixel level below the critical value and raises the pixel level above the critical value is carried out.

Description

Image processing method of gene chip {METHOD FOR HANDLING AN IMAGE OF DNA CHIP}

The present invention relates to an image processing method of a gene chip, and more particularly, to a method of sharply processing an image of a DNA chip, which is a human tissue sample, for diagnosing a human disease.

In recent medical fields, disease diagnosis using an in-vitro diagnosis system is rapidly spreading. The in vitro diagnostic system refers to a diagnosis of various human diseases or genetic diseases by reading and analyzing a tissue sample obtained from a human body, that is, a gene chip. For the purpose of reading and analyzing such a gene chip, a gene reader having a scanner that scans light into the gene chip and quantifies the light reflected from the gene chip is used.

Meanwhile, when analyzing a gene chip using a scanner, a fluorescent probe is used as an analysis medium. Fluorescent material is a material that emits light of a specific wavelength longer than the scanned wavelength when the light of a particular wavelength is scanned. Using these characteristics, if a fluorescent material having different optical properties is used, various materials can be examined at the same time. In order to scan light of a specific wavelength with a fluorescent material, a suitable light source and an optical filter for selecting only light of a desired wavelength are required. In addition, in order to detect the light emitted from the fluorescent material, another optical filter that collects the emitted light and selects only the light belonging to the emission wavelength of the fluorescent material from the collected light should be used. Should be quantified.

Scanners with this function use high-density polychromatic phosphors to analyze many genetic diseases from the genetic chip to be read at once, so lasers are mostly used as light sources to increase sensitivity and resolution. Photo-multiplier tube (PMT) is used. Since the laser is used as a point light source method, the resolution can be up to 5 to 10 μm, and the photosensitivity of the light magnifier can be up to 1 molecule / μm ² .

In order to scan the entire area of a general slide having a width of 25 mm and a length of 75 mm within 5 minutes, an apparatus capable of transferring a light source or a slide in a short time is employed in the scanner. As a method of transporting the light source, a method of controlling the mirror located in the path through which the laser passes at a high speed to move the laser beam in a zigzag form on the slide surface is used. On the other hand, a dedicated X-Y stage is mostly used for the method of moving a slide.

Meanwhile, in order to remove background noise as much as possible from the fluorescence emitted from the gene chip dotting on the slide surface, most scanners use a confocal method. The confocal method is a method in which a very small pin hole is placed in the path of light so that only light that is scanned at a desired distance can pass.

A schematic configuration of a general gene reader using this confocal method is shown in FIGS. 1 and 2. First, referring to FIG. 1, a laser beam emitted from a laser light source (not shown) is passed through a band-pass filter (1: band-pass filter) for passing only a specific wavelength thereof by a beam splitter (2). Is switched 90 °. Subsequently, the laser beam is incident on the slide 3 to which the gene chip is attached, and as shown, the slide 3 is out of the focal position of the laser beam. The light emitted by the fluorescent material of the gene chip is collected by the objective lens 4, and then its path is again converted by 90 degrees by the other mirror 5. Then, light passes through another bandpass filter 6 through which only light corresponding to the emission wavelength of the fluorescent material passes, and then enters the confocal membrane 8 through the sensing lens 7. At this time, as described above, since the light is out of the focus position, the light does not pass through the pin hole 8a of the confocal membrane 8.

On the other hand, as shown in FIG. 2, if the laser beam is incident on the slide 3 at the focal position precisely, the light collected through the sensing lens 6 will pass through the pinhole 8a of the confocal membrane 8 accurately. Thus, it is possible to enter the sensing unit 9. At this time, for the scanning of the entire gene chip adhered to the slide 3, the movement of the light source or the slide 3 in zigzag is precisely controlled.

The signals recognized by the detector 9 are converted into an image by their processing units and stored. At this time, since these images are displayed as dots of very small size every moment, independent image processing software which collects, processes and reads all these images after completion of scanning of all light for the entire inspection area is required.

The signals recognized by the detector are displayed on a computer monitor, and the screen is used to determine whether the gene chip is abnormal. However, in the related art, the luminance of the optical signal recognized by the sensing unit is weak and noise is mixed with the optical signal, causing unnecessary points to be displayed on the screen. Since these points are not clearly distinguished from the points indicating whether the gene chip is abnormal, there is a problem of lowering the reliability of the reading result.

Accordingly, the present invention has been made to solve the problems of the conventional image processing method, and the unnecessary points generated due to the luminous intensity and noise are not displayed on the screen, thereby improving the reliability of the reading result of the gene chip. It is an object of the present invention to provide a method for processing an image of a gene chip.

1 and 2 are schematic configuration diagrams of a general scanner.

3 illustrates a process of superimposing a virtual mask image on a detection image according to the present invention.

4 is a diagram illustrating a state in which a detection image having a square pixel and a virtual mask image overlap each other according to an embodiment of the present invention.

5 is a diagram illustrating a state in which a detection image having circular pixels and a virtual mask image are overlapped according to another exemplary embodiment.

6 is a flowchart sequentially illustrating an image processing method according to the present invention.

-Explanation of symbols for the main parts of the drawing-

10; Detection image 11; pixel

20,30; Virtual mask image 21,31; Transmission window

In order to achieve the object of the present invention described above, the image processing method of the image chip according to the present invention consists of the following steps.

First, the method includes inputting a standard image having pixels according to the shape of a gene chip and a detection image having a plurality of pixels corresponding to each pixel of the standard image. Subsequently, a virtual mask image is created having transmission windows corresponding to the pixels of the standard image. Then, the virtual mask image is superimposed on the detection image such that the transmission windows of the generated virtual mask image correspond to each pixel of the detection image, so that only pixels of the detection image are displayed through the transmission windows of the virtual mask image.

Preferably, after each image superimposing step, comparing the pixel level of the detected image displayed through the transmission window with a preset threshold. Subsequently, a low pass filtering process is performed that lowers the pixel level lower than the threshold and conversely raises the high pixel level.

With the above configuration, since the virtual mask image is superimposed on the detection image and displayed on the screen, various noises of the detection image are hidden by the virtual mask image, so that only pixels of the detection image can be clearly displayed on the screen. do.

Next, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

3 is a view illustrating a process of superimposing a virtual mask image on a detection image according to the present invention, and FIG. 4 illustrates a state in which a detection image having a square pixel and a virtual mask image are overlapped according to an embodiment of the present invention. 5 is a diagram illustrating a state in which a detection image having a circular pixel and a virtual mask image overlap each other, and FIG. 6 is a flowchart sequentially illustrating an image processing method according to the present invention.

First, referring to FIG. 3, in the image processing method according to the present invention, it is essential to superimpose a virtual mask image 20 on an image of light reflected from a fluorescent material applied to a gene chip, that is, a detection image 10. .

That is, on the detection image 10, pixels 11 representing the degree of infection of the gene chip are displayed according to the shape of the gene chip, and various noises 12 are also displayed. Since the noise 12 and the pixels 11 are not easily distinguished on the screen, in the present invention, only the pixel 11 by overlapping the virtual mask image 20 covering the noise 12 on the detection image 10. Make sure only the fields are visible.

To this end, a plurality of transmission windows 21 according to the shape of the gene chip are formed in the virtual mask image 20, so that only the pixels 11 of the detection image 10 are displayed on the screen through the pixels 21. It becomes possible.

4 shows that only the pixels 11 of the detection image 10 are displayed through the transmission window 21 of the virtual mask image 20 according to the method of the invention. As shown, the noises 12 of the detected image 10 are masked by the virtual mask image 20, and only the detected pixels 11 are displayed through the transmission window 21.

Meanwhile, in FIGS. 3 and 4, although the transmission window 20 of the virtual mask image 20 is shown to be square, the transmission mask 20 is not necessarily limited to the shape, and the virtual mask having the circular transmission window 31 as shown in FIG. Image 30 may also be used. That is, the pixel shape of the virtual mask is changed according to the shape of the genetic chip.

Hereinafter, a method of processing an image of a gene chip according to the present embodiment on the assumption of the basic processing method described above will be described in detail with reference to the flowchart of FIG. 6.

First, in step ST1, a standard image according to various types of gene chips is input into a computer, and then a detection image of the gene chip photographed using a scanner is input into the computer. Here, the standard image refers to an image of a gene chip that is currently used as a sample among various types of gene chips. That is, each pixel of the detected image and the standard image correspond one-to-one.

Then, in step ST2, a virtual mask image having a size equal to the standard image size is generated. The virtual mask image has a transmission window corresponding to the plurality of pixels formed in the standard image, as shown in FIG.

Then, as in step ST3, the generated virtual mask image is superimposed on the detection image. Of course, the transmission windows of the virtual mask image overlap so as to correspond with the pixels of the detection image, so that each pixel is exposed through the transmission windows. Then, only the expressed pixels among the pixels of the detected image are generally displayed in gray, and these gray pixels are displayed on the screen through the transmission window. The gray color level indicates the extent of infection of the gene.

On the other hand, various noises displayed in the detection image are not exposed through the transmission windows and are masked by the virtual mask image, so that only pixels, particularly expressed pixels, are displayed on the screen.

Pixels expressed on the screen may be clearly displayed only by such a process, but it is preferable to perform the following process for clearer pixel identification.

First, as in step ST4, the pixel level of the detected image displayed through the transmission window is compared with a preset threshold. Since the threshold value is a criterion for determining whether or not the pixel is expressed, it is preferable that the threshold value is not set to any one value but set to a predetermined range up and down.

As a result of the comparison, if the pixel level is higher than the threshold value, the filtering operation is performed to make the color of the pixel more clear by raising the pixel level as in step ST5. On the contrary, if the pixel level is lower than the threshold value, i.e., if it is estimated that the gene is not expressed, the filtering operation is performed to lower the pixel level by lowering the pixel level as in step ST6.

That is, a filtering process is performed in steps ST5 and ST6 so that only the expressed pixels are displayed more clearly on the screen, and the unexpressed pixels are not easily seen. Here, the filtering is generally low pass filtering, and weight filtering which weights among these low pass filtering is employed. The weighting means that the pixels are multiplied by the weight to make the desired pixel sharper and vice versa.

When this filtering operation is completed, finally, the output image is displayed on the screen as in step ST7. Here, the output image refers to an image in which a virtual mask image is superimposed on the detection image so that only pixels are displayed through the transmission windows and noise is masked. Several colors may be added to this output image to allow the user to see the rendered pixels more clearly.

As described above, according to the present invention, by overlaying the virtual mask image on the detection image and displaying it on the screen, the noise of the detection image is not displayed by being hidden by the virtual mask image, and only the expressed pixels of the virtual mask image It is displayed through the transmission window. Therefore, whether or not the expression of the gene chip can be seen more clearly on the screen. As a result, the reliability of the reading result of the gene chip is greatly improved.

Although the present invention has been described in detail with reference to preferred embodiments, the present invention is not limited to the above embodiments, and various modifications may be made by those skilled in the art within the scope of the technical idea of the present invention. .

Claims (4)

A method of processing and displaying an image of a gene chip on a screen, Inputting a detection image of the gene chip having a plurality of pixels; Generating a virtual mask image having a transmission window corresponding one-to-one with a plurality of pixels of the detected image; And Superimposing the virtual mask image on a detection image such that only pixels of the detection image are displayed through the transmission windows of the virtual mask. The method of claim 1, wherein after each image overlapping step, Comparing the level of the pixel displayed through the transmission window with a preset threshold value; And And a filtering step of selectively raising or lowering the level of the pixel according to the comparison result. 3. The method of claim 2, wherein a low pass filtering method is used in the filtering step. 4. The method of claim 3, wherein the low pass filtering method is a weight filtering method for selectively assigning a weight to a filter level according to a comparison result.