JPH08329248A - Feature quantity detection system for displayed graphic - Google Patents

Abstract

PURPOSE: To provide the detection system which suppresses an effect of unnecessary graphics included in a picked-up picture signal in the system which detects the feature quantity of target graphics displayed on a display device. CONSTITUTION: In an operation processing part 5 for feature quantity, a labeling means 52 which compares a prescribed picture element of a picked-up picture signal 104 with a threshold 151 to give a label is provided to distinguish target graphics 102 and unnecessary graphics included in the picked-up picture signal 104, and only target graphics are extracted to detect a feature quantity 105.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a graphic (hereinafter referred to as "target graphic") on which a feature quantity displayed on a display means is to be detected.
The above) relates to a system for detecting feature quantities.

[0002]

2. Description of the Related Art In a direct-view CRT display device or a projection display device, screen distortion correction, color misregistration correction, focus adjustment, and the like can be adjusted based on an image displayed on the screen of the display device. Many. In order to perform this adjustment stably and accurately, as a means for objectively acquiring the correction amount, a system for detecting the feature amount related to the item to be corrected, such as the position of the center of gravity of the target figure, the brightness value, the power of the high frequency component, etc. Is required.

An example of a detection system in which the characteristic amount to be detected is a screen distortion correction amount will be described below. This detection system
The target figure is displayed on the display device, the area including the displayed target figure is photographed by, for example, a CCD camera as an image input means, and the barycentric position of the target figure included in the image information obtained by this photographing is determined. The amount of screen distortion correction is objectively evaluated by the calculation.

FIG. 17 is a block diagram showing the configuration of a conventional screen distortion correction amount detection system. Reference numeral 1 is a video signal 1 of a target figure.
A video signal generator for generating 01, 2 is a video signal 101
The display device 3 for displaying the image C and the image signal 103 are acquired by capturing an area including the target graphic 102 C
A CD camera, 4 is a frame memory for storing the video signal 103 and the image information 104 thereof is read out, and 5 is an arithmetic processing means for calculating the barycentric information 105 of the target figure from the image information 104 read out from the frame memory 4, It is composed of a threshold value calculation means 51 for calculating the threshold value 151 from the image information 104 and a center of gravity calculation means 54 for calculating the center of gravity information 105 based on the threshold value 151. Reference numeral 6 is a system control means for controlling the entire system.

Next, the operation will be described. In accordance with an instruction from the system control means 6, the video signal 101 of the target graphic is output from the video signal generator 1, and the target graphic 10 is displayed on the display device 2.
2 is displayed. The displayed target figure 102 is photographed by the CCD camera 3, and the video signal 103 output from the CCD camera 3 is temporarily stored in the frame memory 4 according to an instruction from the system control means 6 and is stored in the threshold value calculation means 51 as image information 104. The threshold value 151 is read out and, for example, the threshold 151 is calculated from the maximum value zmax and the minimum value zmin of the brightness value of the image information 104 by the following equation. δ = (zmax + zmin) / 2 (1)

Next, the center-of-gravity calculation means 54 calculates the center-of-gravity information 105 of the target graphic 102 by using the following equation for the pixels having a threshold value δ or more in the image information 104. xg = Σ (xi · zi) / Σzi (2) yg = Σ (yi · zi) / Σzi (3) where xi, yi, and zi are the i-th Pixel x
The coordinates, the y coordinate, and the brightness value are represented, and (xg, yg) means the center of gravity information. When obtaining the correction amount of the screen distortion, the center of gravity information 1
The difference between 05 and the center of gravity information on the ideal screen that was obtained in advance is the correction amount.

[0007]

In the conventional feature quantity detecting system as described above, for example, as shown in FIG.
In the video signal 103 obtained by photographing the target figure 102 displayed on the display device 2 with the CCD camera, figures b and c due to noise and reflection of surrounding objects are included in addition to the target figure 102. For this reason, the brightness information of the graphics b and c exceeding the threshold value δ other than the brightness information of the target graphic 102 is also the target of the gravity center calculation, and the gravity center position P including the graphics b and c other than the target graphic 102 is calculated. There was a point.

The present invention has been made for the purpose of solving the above-mentioned problems, and provides a feature quantity detection system for a display figure capable of eliminating the influence of the figure other than the target figure such as noise and glare of surrounding objects. The purpose is to get.

[0009]

A feature detection system for display graphics according to the present invention comprises a labeling means for labeling graphics included in image information, and a labeling graphic, The target figure is provided with means for extracting the figure closest to the shape and size of the target figure as the target figure.

Further, when extracting a figure from image information,
It is provided with a means for extracting a figure from image information obtained by photographing a plurality of times and extracting a figure existing a plurality of times as a target figure.

In addition, the target graphic is displayed by extracting the graphic once or more from the image information when the target graphic is displayed on the display means and the image information when the target graphic is not displayed. A means for extracting a figure existing only in the image information at that time as a target figure is provided.

Further, before the labeling means, there is provided expansion processing means for performing expansion processing in a single direction or a plurality of directions on each pixel of the image information.

Further, the labeling means includes expansion processing means for performing expansion processing in each direction of the image information in a single direction or in a plurality of directions.

[0014]

The feature amount detection system according to the present invention clarifies the graphics included in the image information by labeling each pixel of the captured image information, and the shape and size of these graphics are targeted. The one closest to the figure is extracted as the target figure.

Further, by labeling each pixel of the image information photographed a plurality of times, the figure included in each image information is clarified, and the figure whose shape and size do not change is the target figure. To extract.

Further, when the target graphic is displayed on the display means and when it is not displayed, each pixel of the image information photographed at least once is labeled so as to be included in each image information. A figure that exists only when the target figure is displayed is extracted as the target figure.

Further, by subjecting each pixel of the image information to expansion processing in a single direction or in a plurality of directions, the target figure which is spatially or temporally divided is recognized as one figure.

Also, by integrating the expansion processing means and the labeling means, the circuit scale of the processing means or the processing time can be reduced.

[0019]

【Example】

Example 1. An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of the first embodiment,
The same reference numerals as in FIG. 17 denote the same or corresponding portions, and 52 is the image information 104 based on the threshold 151.
Labeling means for labeling each pixel to clarify the figure, and 53 is a figure extracting means for extracting a target figure from the figures included in the image information 104.

Next, the operation will be described. The operation until the threshold value calculation means 51 calculates the threshold value 151 is the same as that of the conventional example, and therefore its explanation is omitted. The labeling unit 52 performs a labeling operation on predetermined pixels having a threshold value of 151 or more among the pixels of the image information 104. Here, a case will be considered in which the pixels are horizontally scanned from the upper left of the image, and the pixels consecutive as the predetermined pixels are labeled for each pixel while sequentially scanning downward.

FIG. 2 is an explanatory diagram of labeling performed on each pixel during scanning, and FIG. 3 is a flowchart thereof.
In FIG. 2, when C is a pixel currently being scanned, C is considered as a target pixel and a target region, and A and B are considered as reference pixels. Explaining along the flowchart of FIG. 3, if the luminance value of the target pixel C is equal to or larger than the threshold 151, it is determined that the target pixel C is the target of labeling, and the labels attached to the reference pixels A and B are labeled. Look at and label the target pixel. That is, if any one of the reference pixels A and B has a label, the label is attached to the target pixel C, and if neither of the reference pixels A and B has a label, the target pixel C is attached. Give a new label to.
If both the reference pixels A and B have labels and the labels are different, the labels are linked by rewriting them to the same label.

FIG. 4 shows the labeled image information 152. By comparing the target graphics 102 with the graphics A, B, and C revealed by the labeling, the targets displayed on the display device 2 are shown. The target figure A obtained by photographing the figure 102 can be separated from the other figures B and C.
The figure extracting means 53 extracts the target figure A having the size and shape closest to the target figure 102 displayed on the display device 2 among the figures A, B, and C. The center-of-gravity calculation unit 54 calculates the center-of-gravity information 105, similarly to the conventional example, only for the target graphic A extracted by the graphic extraction unit 53. Even when it is desired to obtain the correction amount of the screen distortion, the difference between the center of gravity information 105 and the center of gravity information of the ideal screen obtained in advance is used as the correction amount, as in the conventional example.

Embodiment 2 FIG. In the first embodiment, the video information 1
Other than the target figure A included in 04, the figures B and C due to temporarily generated noise are also labeled.
It is necessary to compare the size and shape with the target figure 102.
In the second embodiment, the display surface on which the target graphic 102 is displayed is photographed a plurality of times to obtain a plurality of pieces of image information, and the pieces of image information are compared with each other to exclude a moving figure or a temporarily generated figure. It is configured as follows.

Since the entire structure of the detection system of the second embodiment and the internal structure of the arithmetic processing means 5 in the detection system are the same as those of the first embodiment, the description thereof will be omitted.

Next, the operation will be described. In order to compare a plurality of image information, it is necessary to prepare the storage means 4 capable of storing the number of images to be acquired. However, in the second embodiment, in order to reduce the storage capacity of the frame memory 41, The graphic information up to the screen is held as the label information held by the labeling means 52. The operation until the threshold 151 is calculated from the video information 104 and the operation after the graphic extraction means 53 are the same as those in the first embodiment, and therefore the description thereof is omitted.

In the labeling means 52, the first first image information is labeled in the same manner as in the first embodiment. For the second and subsequent images, as shown in FIG. 5, assuming that the pixel currently being scanned is at the position
The target pixel is the target pixel, the pixel position at the same position on the previous screen is labeled, and the luminance value of the target pixel is the threshold value 15
Only when the number is 1 or more, the target pixel number is targeted for labeling. In the rest of the processing, labeling is performed in the same manner as in the first embodiment, using K, K, and K as reference pixels and K as the target region. By this operation, as shown in FIG. 6, pixels of a figure having a dynamic element such as a figure temporarily generated by noise or a moving object image is not labeled, and a still image is not displayed. Only the labels will be added, so shapes with dynamic elements can be eliminated.

Embodiment 3 FIG. In the third embodiment, only the target graphic A is extracted by acquiring the image information 104 for each of the case where the target graphic 102 is displayed and the case where the target graphic 102 is not displayed, one or more times. is there.

Since the entire structure of the detection system of the third embodiment and the internal structure of the arithmetic processing means 5 in the detection system are the same as those of the first embodiment, the description thereof will be omitted.

Next, the operation will be described. Display means 2
The instruction to display and delete the target graphic 102 displayed in
This is performed by the system control means 6 issuing an instruction to the video signal generator 1. Other than that, the operation until the threshold 151 is calculated and the operation after the graphic extraction means 53 are the same as those in the first embodiment, and therefore the description thereof is omitted.

In the third embodiment, first, the same labeling as in the first or second embodiment is performed by the labeling means 52 for the image information 104 obtained by photographing the display surface displaying the target graphic 102. Next, in the image information 104 obtained by photographing the display surface from which the target graphic 102 is erased, if the pixel at the same position as the pixel labeled in the previous process has a threshold value of 151 or more, the label attached in the previous process is erased. With
Pixels having a threshold value of 151 or more are subjected to a process of not labeling them. By this processing, only the target figure is labeled as shown in FIG. 7, and still figures other than the target figure can be excluded.

Example 4. In the first to third embodiments described above, when the display device is a CRT type front projection display device, there is a gap between the scanning lines as shown in FIG. Nevertheless, they are labeled as figures D, E, F, G divided for each scanning line. Therefore, as a result, the figure is separated into four figures, and the target figure cannot be found or is erroneously recognized. Therefore, in the fourth embodiment, by performing expansion processing in the vertical direction of pixels to fill the gaps between figures before labeling, the figures are divided by the gaps of the scanning lines as shown in FIG. I tried to avoid.

Since the entire structure of the detection system of the fourth embodiment is similar to that of the conventional example, the description thereof will be omitted. FIG. 10 is a block circuit diagram of the arithmetic processing means 5 of the fourth embodiment, and the same reference numerals as those in FIG. 1 denote the same or corresponding portions, and 55
Is an expanding unit that expands pixels based on the threshold 151, and 52 is a labeling unit that labels predetermined pixels of the expanded image information 154.

Next, the operation will be described. The operations until the threshold value calculation means 51 calculates the threshold value 151 and the operations after the labeling processing means 52 are the same as those in the first embodiment, and therefore the description thereof is omitted. The expansion processing unit 55 expands pixels having a threshold value of 151 or more in the vertical direction by a predetermined number of pixels. For example, when the pixel position shown in FIG. 11 is currently being scanned, if the brightness value of the pixel is equal to or higher than the threshold value 151, it is notified to the following processing means that the pixels of the source are equal to or higher than the threshold value. By this operation, the figures D and E, E and F, and F and G shown in FIG. 8 can be adhered to each other.
It is possible to fill the gap between the four scanning lines. In the labeling process, by using the image information after this expansion,
Each figure included in the image information 104 is set to 1 without being divided at a position corresponding to a gap between scanning lines.
It can be processed as an individual figure.

Example 5. In the fourth embodiment, when the display device is a direct-view display device with a shadow mask, a display device using liquid crystal, a rear projection display device, or the like, a shadow mask, electrodes for driving the liquid crystal, and a lenticular screen, respectively. Due to the effect of shadows such as black stripes, the figure displayed as shown in FIG. 12 is finely divided, and it is difficult to restore the divided figure into one continuous figure only by expanding in the vertical direction. . In view of this, in the fifth embodiment, by expanding each pixel in the vertical direction and the horizontal direction before performing labeling, even a finely divided figure is filled with a figure gap as shown in FIG. It is possible to exclude that the recognition of the figure is hindered by the shadow that divides the image.

Since the entire structure of the detection system of the fifth embodiment and the internal structure of the arithmetic processing means 5 in the detection system are the same as those of the fourth embodiment, the description thereof will be omitted.

Next, the operation will be described. In FIG. 10, until the threshold value calculation means 51 calculates the threshold value 151,
The operation after the labeling processing means 52 is the fourth embodiment.
The description is omitted because it is similar to the above. The expansion processing unit 55 expands the figure for a pixel having a threshold value of 151 or more in the vertical and horizontal directions by a predetermined number of pixels. For example, when the position of the pixel D shown in FIG. 14 is being scanned at present, if the brightness value of the pixel D is equal to or higher than the threshold 151, it is notified to the processing means below that the pixels SE to D are equal to or higher than the threshold. By this operation, the finely divided figures shown in FIG. 12 can be fused to each other, and the gap due to the shadow of the figures included in the image information 104 can be filled. By using the expanded image information in the labeling process, each figure included in the image information 104 is processed as one figure without dividing the figure at the position of the shadow. You can

Example 6. In the fifth embodiment, since only the two-dimensional expansion process is performed, when the display device 2 and the CCD camera 3 have different vertical scanning frequencies, or the display device 2 and the CCD camera 3 are temporarily shielded from light. In some cases, such as when an object passes, the target figure 102 cannot be captured in a perfect shape. Therefore, in the sixth embodiment, the target graphic 102 is photographed a plurality of times to obtain a plurality of image information 104, and each image information 10 is acquired.
Before each 4 pixel is labeled, it is expanded in three directions of the vertical direction, the horizontal direction, and the time axis direction, and the temporarily missing figure is temporally interpolated and recognized as one figure. By doing so, the effect of temporary hiding of the figure is avoided.

Since the entire structure of the detection system of the sixth embodiment and the internal structure of the arithmetic processing means 5 in the detection system are the same as those of the fourth embodiment, the description thereof will be omitted.

Next, the operation will be described. In FIG. 10, until the threshold value calculation means 51 calculates the threshold value 151,
Also, since the operation of the labeling processing means 52 and thereafter is similar to that of the other embodiments, the description thereof will be omitted. Expansion processing means 55
Then, the pixels having the threshold value 151 or more are expanded in the vertical, horizontal, and time axis directions by a predetermined number of pixels and for a predetermined time.
For example, when the position of the pixel number shown in FIG. 15 is being scanned at present, if the luminance value of the pixel number is equal to or higher than the threshold value 151, it is notified to the following processing means that the pixel numbers are equal to or higher than the threshold value.
By this operation, an expanded three-dimensional image can be obtained, and the gap due to the temporary concealment of the target figure can be filled.
By using the image information after the expansion for the labeling process, the target graphic can be processed as one graphic without being divided at the time of being temporarily hidden. Furthermore, since time constraints are added to the figure extraction conditions, it is possible to suppress the effects of noise and the like that are temporarily generated.

Example 7. Although the expansion processing means 55 and the labeling means 52 are described as separate processing in the above-described fourth to sixth embodiments, the labeling and the expansion processing can be performed at the same time. Here, the case of the two-dimensional expansion processing shown in the fifth embodiment will be described as an example.

Considering that the expansion processing is incorporated in the labeling means 52, the overall construction of the detection system of the seventh embodiment and the internal construction of the arithmetic processing means 5 in the detection system are the same as those of the first embodiment. Therefore, the description is omitted.

Next, the operation will be described. In FIG. 1, the operation until the threshold value calculation means 51 calculates the threshold value 151 and the operation after the graphic extraction means 53 are the same as those in the other embodiments, and therefore the description thereof will be omitted. In the labeling means 52,
The pixel Y shown in FIG. 16 is set as the pixel currently being scanned, and the predetermined pixel to be labeled is set in units of one pixel in the horizontal and vertical directions, and the expansion range is 2 in the upward and left directions.
Assuming pixels, yo is the target pixel, ha is the reference pixel, and ho is the target pixel.
Labeling is performed in the same manner as in the other embodiments with yo as the target area. As a result, while performing labeling, two pixels are simultaneously expanded in the upward and leftward directions. By performing the expansion processing and the labeling at the same time, the scale of the processing means or the time required for the processing can be reduced.

By the way, in each of the above-described embodiments, the case where the present invention is applied to the calculation of the position of the center of gravity of the display graphic has been described, but the invention can be similarly applied to the calculation of other characteristic amounts such as the brightness value, the color temperature, the focus and the like. Needless to say.

[0044]

Since the present invention is constructed as described above, it has the following effects.

Each pixel of the photographed image information is compared with a threshold value for labeling, the labeled figure is compared with the target figure of the video signal, and the most approximate figure is extracted as the target figure and the target figure is obtained. Since the feature amount of the figure is configured to be calculated, the feature amount of the target figure can be accurately detected.

Further, the target figure displayed on the display means is photographed a plurality of times by the photographing means to obtain a plurality of image information, and the pixel of the current screen at the same position as the pixel labeled the previous screen exceeds the threshold value. If it is, the same label as the label attached to the pixel of the previous screen is attached, and if it does not exceed the threshold, labeling is not performed, and the figure existing in all image information is extracted as the target figure. Since this is done, it is possible to eliminate the effects of noise that is temporarily generated and figures reflected on the display surface.

Further, when the target graphic is displayed on the display means and when the target graphic is not displayed, the image information is obtained at least once, and each pixel of the image information is labeled.
Since a figure existing only when the target figure is displayed among the figures included in each image information is extracted as the target figure, figures other than the target figure can be excluded.

Moreover, since each pixel of the image information is subjected to expansion processing in a single direction or in a plurality of directions before labeling each pixel of the photographed image information, the target figure is spatially or Even if they are divided in time, they can be extracted as one figure.

Further, since the means for subjecting each pixel of the image information to the expansion processing in a single direction or a plurality of directions and the means for labeling are integrated, the circuit scale of the processing means can be reduced and the processing speed can be improved. , And the number of parts can be reduced.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a first embodiment of the present invention.

FIG. 2 is a diagram showing a relationship between a pixel to be labeled and a peripheral pixel according to the first embodiment.

FIG. 3 is a flowchart illustrating a labeling procedure according to the first embodiment.

FIG. 4 is a diagram showing labeled image information according to the first embodiment.

FIG. 5 is a diagram showing a relationship between labeled pixels and reference pixels according to a second embodiment of the present invention.

FIG. 6 is a diagram showing the principle of figure extraction according to the second embodiment.

FIG. 7 is a diagram showing the principle of figure extraction according to the third embodiment of the present invention.

FIG. 8 is a diagram showing image information before expansion according to the fourth embodiment of the present invention.

FIG. 9 is a diagram showing image information after expansion according to the fourth embodiment.

FIG. 10 is a diagram showing a configuration of an arithmetic processing means according to a fourth embodiment.

FIG. 11 is a diagram showing a relationship of pixels to be expanded according to the fourth embodiment.

FIG. 12 is a diagram showing image information before expansion according to the fifth embodiment of the present invention.

FIG. 13 is a diagram showing image information after expansion according to the fifth embodiment.

FIG. 14 is a diagram showing the relationship of pixels to be expanded according to the fifth embodiment.

FIG. 15 is a diagram showing a relationship of pixels to be expanded in Example 6 of the present invention.

FIG. 16 is a diagram showing a relationship of pixels to be expanded in Example 7 of the present invention.

FIG. 17 is a block diagram showing a configuration of a conventional detection system.

FIG. 18 is a diagram showing image information that is equal to or larger than a threshold value in the conventional example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 video signal generator, 2 display device, 3 CCD camera, 4 frame memory, 5 arithmetic processing means, 6 system control means, 51 threshold value arithmetic means, 52 labeling means, 53 graphic extraction means, 54 barycenter arithmetic means, 55
Expansion processing means, 101 video signal, 102 target graphic, 103 video signal, 104 image information, 105 center of gravity information, 151 threshold value, 152 image information after labeling, 153 image information after graphic extraction, 154 image information after expansion.

Claims (5)

[Claims] 1. A feature amount detection system for detecting a feature amount of a graphic displayed on a display device, and a video signal generating means for outputting a video signal of a target graphic whose feature amount is to be detected to the display device, and the display. Input means for acquiring an area including the target graphic displayed on the apparatus, storage means for holding the acquired image information, and means for labeling predetermined pixels of the image information from the storage means by comparing them with a threshold value. When,
The labeled figure is compared with the target figure of the video signal to extract the closest figure as the target figure, and the means for calculating the feature amount of the extracted target figure is provided. A feature amount detection system for a featured display figure. 2. The displayed target figure is acquired by the input means a plurality of times to obtain a plurality of image information, and a figure which exists a plurality of times among the figures included in the image information is extracted as the target figure. The display pattern feature amount detection system according to claim 1, wherein: 3. A plurality of pieces of image information are acquired by the input means at least once each of a case where the target graphic is displayed on the display means and a case where the target graphic is not displayed, which are included in these image information. The feature quantity detection system for a display figure according to claim 1, wherein a figure existing only when the target figure is displayed is extracted as the target figure. 4. A means for performing expansion processing in a single direction or in a plurality of directions on predetermined pixels of the image information before labeling the predetermined pixels of the acquired image information. A feature detection system for a display graphic according to claim 3. 5. A means for performing expansion processing in a single direction or a plurality of directions and a means for performing labeling on a predetermined pixel of image information are integrally configured. The display pattern feature amount detection system described in 1.