JPH041292B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for selecting and detecting only a specific color tone part from an image to be measured in an image analysis apparatus using a color television.

By extracting a portion of a specific tone from a macroscopic or microscopic image, this specific tone portion can be identified as a specific component or a specific tissue. For example, by determining the area of a portion of a specific tone from an image composed of a plurality of components or tissues, the ratio of the components or tissues can be quantified.

For this purpose, conventional technology related to image analysis devices mainly analyzes monochrome images.
There are very few devices that can measure color images, and their performance is also insufficient. However, analysis using monochrome images loses much of the image information unique to the measurement target, so image analysis that takes color tone information into account is desired in many fields, such as medicine, biology, and mining.

Under these circumstances, the present applicant previously proposed a device for detecting an equivalent color tone region in Japanese Patent Application No. 155223/1983 as a device capable of detecting a specific color tone, but this device was developed based on color tone information analysis technology. However, there remained the problem that its application was restricted by the definition of color tone. In other words, the definition of "same color tone" is that the measured color tone is determined to be the same color tone when the output signals of the three primary colors red, blue, and green from the television camera have a constant height in absolute value. Ta. This means that, for example, even if there are two red measurement objects, if one is bright and the other is dark, they will be determined to be different tones. However, there is a demand for certain types of measurement objects to be able to determine the same color tone regardless of brightness, and it has been desired to develop an apparatus that can determine such a same color tone.

An object of the present invention is to provide a specific color tone detection device that can determine that the color tone is the same regardless of brightness or darkness.

To this end, the present invention includes a circuit that determines that the output signals of the three primary colors of red, blue, and green are "the same color tone" if they have a certain ratio, thereby detecting the same color tone regardless of brightness or darkness. It is characterized by being made possible.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows the overall configuration, and an image 1 to be measured is photographed with a color television camera 2.
The color television camera 2 separates the tones of the image 1 into the three primary colors of red, green, and blue signals Sr, Sg, and Sb, and outputs the respective signals Sr, Sg, and Sb to the respective lines l _1a , l _2a , l Output to _3a . Each signal Sr, Sg,
Sb is applied to the respective sample-and-hold circuits 3r, _3g , and _3b via lines _l1b , l2b, and l3b. The sample and hold circuits 3r, 3g, and 3b are each given a color signal from a position pulse generating circuit 4 associated with a joy stick, light pen, etc., for specifying a position having a color tone to be measured. , when a position designation signal is received from this circuit 4, the respective signals Sr', Sg', and Sb' regarding the designated position are held.

Each signal Sr′, Sg′, Sb′ held by each sample-and-hold circuit 3r, 3g, 3b is line
It is given to the maximum value judgment circuit 5 via l _1c , l _2c , l _3c ,
In this circuit, it is determined which signal has the maximum level. The maximum level determination circuit 5 determines the maximum level signals, that is, Sr′, Sg′,
When any one of Sb' is determined, a control signal based on this determination result is given to the distribution circuit 6.
The distribution circuit 6 receives hold signals Sr', Sg', Sb' from each sample-and-hold circuit 3r, _3g , 3b via lines l _1d , l 2d , l _3d and sequentially via lines l _1a , l _1b , l _1c . Each signal Sr, Sg, Sb in scanning is given, and output lines l _A , l _B , l _C ,
It is determined which signal to give to l _D , l _E , and l _F.

Here, any one of the hold signals Sr', Sg', and Sb' determined to be at the maximum level by the maximum value determination circuit 5 is applied to the line _lA , and the scanning signal Sr, Sg, and Sb of the same color is applied to the line lA. one of them is given to line _lD . In addition, the remaining two hold signals Sr′, Sg′,
Two of Sb' are applied to lines l _B and l _C , respectively, and correspondingly two remaining scanning signals
Two of Sr, Sg, and Sb are lines l _E and l _F, respectively.
given to. In other words, when the red hold signal Sr' is at the maximum level as in the above example, the hold signal Sr' and the scanning signal Sr are applied to the lines _lA and _lC , respectively, and at the same time the hold signals Sg', Sb' and scanning signals Sg and Sb are applied to lines l _B and l _C and lines l _E and l _F , respectively.

Lines l _B , l _C , l _E , l _F are divided by divider 7 _A , respectively
_7B , _7C and _7D , and lines _lA and _lD are connected to dividers 7A and _{7B , 7C} and _7D , respectively. These dividers 7 _A , 7 _B , 7 _C , and 7 _D receive the signal from line l _B /signal from line l _A , respectively.
Signal from line l _C /signal from line l _A , signal from line l _E /signal from line l _D , line l _F
It is designed to calculate the ratio of signal from line L/signal from line _lD . In other words, in the case of the above example, the dividers 7 _A and 7 _B each have the hold signal ratios Sg'/Sr' and Sb'/
Sr', and the dividers _7C and _7D calculate the ratios Sg/Sr and Sb/Sr of successive scanning signals, respectively. The ratio thus calculated is as shown in the figure: from divider 7 _A to comparators 8 _A and 8 _B , from divider 7 _B to comparators 8 _C and 8 _D , and from divider 7 _C to comparators 8 _A and 8 _B. , are connected to input from divider 7 _D to comparators 8 _C and 8 _D , respectively. Here, comparators 8 _A and 8 _B , 8 _C and 8 _D constitute a fixed value threshold hold circuit that compares the ratio of the hold signal and the ratio of the scanning signal, respectively, which serve as the reference, and their respective outputs are sent to the AND circuit 9. It has been entered.

With this structure, when you specify the position of a certain tone you want to measure, the ratio of the three primary colors for the specified tone is held and a threshold is provided, and each The proportions of the three primary colors in the parts are compared. In this comparison, when the scanning ratio is included in the given threshold, all the comparators _8A , _8B , _8C , and _8D output, and the AND circuit 9 outputs accordingly. Therefore, within the range where the output of the AND circuit 9 is obtained, the color tone of the measured portion is detected to be the same as the color tone of the designated position.

Here, the reason why the maximum value determination circuit 5 and the distribution circuit 6 are provided is to ensure the operating range of the divider. In other words, when divided by the maximum level signal, the calculated value always falls within the range of 0 to 1. It is.

FIGS. 2 and 3 are for explaining the processing based on the signal ratio described above. As shown in Figure 2, when a certain position Xo is specified while the red, green, and blue signals Sr, Sg, and Sb are changing, the range where this position Xo and the ratios Sg/Sr and Sb/Sr are constant is shown. There is.

In addition, as shown in Figure 3, the ratios Sg/Sr, Sb/Sr
is obtained, and the hold signal ratio Sg′/Sr′, Sb′/
It shows the range in which both ratios are simultaneously included in the threshold given by Sr′ (indicated by a two-dot chain line). The range where both ratios are included at the same time is the range of the same color tone.

As described above, the present invention is capable of extracting, based on a component or tissue at an arbitrary position on the screen, the area of the same component or tissue in the same screen. can.

For this purpose, the ratio of the three primary colors at the specified position is determined, and the range that includes the ratio of the three primary colors in the measurement area is detected as the same color tone based on the threshold set based on this ratio. It becomes possible to detect the color tone of color images that do not have color images.

Since it has a configuration that specifies a reference position, measurements can be performed quickly. Furthermore, since the reference position and other positions are compared, the influence of illumination can be avoided.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of an apparatus according to an embodiment of the present invention. FIG. 2 and FIG. 3 are explanatory diagrams for explaining signal processing. 1... Image, 2... Color television camera, 3r, 3g, 3b... Sample hold circuit, 4
... Position pulse generation circuit, 5 ... Maximum value judgment circuit, 6 ... Distribution circuit, 7 _A , 7 _B , 7 _C , 7 _D ... Divider, 8 _A , 8 _B , 8 _C , 8 _D ... Comparator, 9...AND circuit, Sr, Sg, Sb...scanning signal, Sr', Sg',
Sb′...Hold signal.

Claims (1)

[Claims] 1. A sample-and-hold circuit that holds each of the red, green, and blue output signals of a color television camera with respect to a specified position in the image, and a first circuit that calculates the ratio of the levels of each signal held by the sample-and-hold circuit. and red by scanning,
a second circuit that calculates the ratio of the levels of the green and blue output signals; and a third circuit that compares the ratio obtained by the first circuit with the ratio obtained by the second circuit. and a fourth circuit that outputs when it is determined by the comparison that the ratio is equivalent, and when the output of the fourth circuit is obtained, the color tone of the corresponding part is the same as the color tone of the specified position. A specific color tone detection device configured to detect a specific color tone.