JP2002008009A - Image processing condition determination method and device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To regularly provide an image suitable to image readability even when an image processing is performed in a condition automatically set according to a region in an image processing condition determination device. SOLUTION: An image processor 40 is provided with a region information gaining means 41 for gaining the information showing the region of a subject; a characteristic quantity gaining means 42 for histogram-analyzing an inputted image data D1 to determine a prescribed characteristic quantity; an image processing condition determination means 43 for determining the condition of image processing on the basis of the gained information showing the region of the subject and characteristic quantity; and an image processing means 44 for subjecting the image data D1 to image processing according to the determined condition. In mammography, since the distribution of histogram is varied according to mammary gland quantity, the intensity (image processing condition) of frequency emphasis processing is determined on the basis of a characteristic quantity such as the median value showing the characteristic of the distribution. Accordingly, when a preferable image processing condition according to the breast as the region and the mammary gland quantity is automatically set, an image suitable for image readability can be regularly provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image processing condition determining method and apparatus for determining image processing conditions to be applied to a medical image obtained by photographing a subject.

[0002]

2. Description of the Related Art When a medical image obtained by capturing an image of a subject is used for diagnosis, image processing corresponding to a target region of the subject is performed so that an image output on a CRT or a film is easily read. Is generally applied.

As a form of performing a diagnosis using an image subjected to image processing as described above, for example, there is mammography (breast diagnosis). In this mammography, a tumor shadow, which is a low-frequency band image, is mainly distinguished from a calcified image, which is a high-frequency band image, and image processing is performed. Generally, the image is subjected to a frequency emphasis process, a dynamic range compression process, or the like based on the characteristics of the frequency band of each image so that the high frequency band is emphasized.

[0004] A chest X having a lung at the site of interest of the subject.
In a usage form in which a radiograph is taken to diagnose a lung cancer or the like, a frequency emphasis process is generally performed so that a lung field portion can be clearly seen.

Here, image processing conditions such as processing parameters used in image processing are determined in advance so that an image suitable for image interpretation can be obtained for each part based on information on a target part (diagnosis target part) of the subject. The image processing is performed by setting the standard conditions (hereinafter referred to as standard conditions). This makes it possible to always obtain an image on which preferable image processing has been performed, regardless of the position of the subject.

[0006]

However, depending on the difference in physique of a patient (individual difference), an image processed under standard conditions set according to a part may be insufficient in image reading ability. .

[0007] In this case, conventionally, first, standard conditions corresponding to a part are set, image processing is performed and image confirmation is performed, and then image processing conditions are set so that an image more suitable for image interpretation is obtained for each image. , That is, re-adjusting the image processing conditions according to the individual difference according to the operator's instruction, which is troublesome.

The present invention has been made in view of the above circumstances, and is suitable for image interpretation even if the subject is different, and as long as at least the part is the same, without re-adjustment by an operator command. It is an object of the present invention to provide an image processing condition determining method and apparatus capable of constantly obtaining an image.

[0009]

According to the investigation by the inventors of the present invention, the readability of an image that has been subjected to image processing under standard conditions corresponding to the part is determined by the state of the part due to the physique and the like. If it has a certain relationship with the individual difference of the subject, and if the state of the part is different, the image data value will be slightly different, so the individual difference of the subject is recognized by distinguishing the difference of the image data value, etc. It has been found that by using this result to determine the image processing conditions, the necessity of adjusting the image processing conditions can be reduced. The present invention has been made based on such findings.

That is, an image processing condition determining method according to the present invention is an image processing condition determining method for determining image processing conditions to be applied to a medical image obtained by photographing a subject. The image processing conditions are determined based on subject information representing various characteristics.

The “subject information representing the physical characteristics of the subject” includes, for example, so-called individual differences such as a difference in the weight of the subject, whether or not the subject is fat, a difference in the thickness of the breast, or a difference in the amount of the mammary gland. Any information may be used.

In the image processing condition determining method according to the present invention, image processing conditions are determined by adjusting standard image processing conditions (standard conditions) set for each part of a subject based on subject information. Or by selecting an image processing condition corresponding to the subject information of the photographed subject from among a large number of image processing conditions set for each part of the subject and for each subject information to determine the image processing condition. Can do it.

Here, in the image processing condition determining method when the subject is a breast, it is preferable that the subject information indicates the amount of the mammary gland.

In the image processing condition determination method of the present invention, the subject information can be a feature amount obtained by analyzing the acquired medical image, in other words, a feature amount obtained by analyzing the medical image. Can be used as the subject information.

The "feature amount" is reflected in image data due to individual differences between subjects. For example, when a breast is a part, a breast having a large amount of gland, a medium breast, and a small breast Thus, even in the case of images of the same site, differences in the state (characteristics) of the site can be distinguished. As the feature amount, for example, a median value, an average value, or the like obtained by performing histogram analysis on image data, or an S value that is an index representing reading sensitivity can be used. In the histogram analysis, a cumulative histogram may be created, an index value indicating a difference in histogram shape such as a signal value reaching a predetermined frequency may be obtained, and the index value may be used as the feature amount.

When a feature obtained by analyzing a medical image is used as subject information, it is desirable that the feature indicates a reading condition or a standardization condition.

The "reading condition" refers to the reading sensitivity (S value) obtained by EDR (Exposure Data Recognizer) processing for prefetching, as disclosed in Japanese Patent Application Laid-Open No. 58-67240 by the present applicant. It means an index called latitude (L value).

The "normalization condition" is defined as disclosed in Japanese Patent Application Laid-Open No. 2-108175 by the present applicant.
It means the condition of the conversion process at the time of data conversion used in the EDR process without performing prefetching.

An image processing condition determining apparatus according to the present invention is an image processing condition determining apparatus for determining image processing conditions to be applied to a medical image obtained by photographing a subject, and acquires part information indicating a part of the subject. Part information obtaining means, subject information obtaining means for obtaining subject information representing physical characteristics of the subject, and image processing conditions for determining image processing conditions based on the obtained part information and the obtained subject information And determining means.

In the image processing condition determining apparatus according to the present invention, the image processing condition determining means adjusts the standard image processing conditions set for each part of the subject based on the subject information to thereby determine the image processing conditions. The image processing conditions are determined by making a decision or selecting image processing conditions corresponding to the subject information of the photographed subject from among a large number of image processing conditions set for each part of the subject and each subject information. A decision may be made.

The subject information acquiring means of the image processing condition determining apparatus of the present invention may acquire a feature representing the amount of the mammary gland as the feature when the part information relating to the breast as the part of the subject is acquired. desirable.

In the image processing condition determining apparatus according to the present invention, the subject information acquiring means may use a feature amount obtained by analyzing the acquired medical image as subject information.

In this case, it is desirable that the characteristic amount indicates a reading condition or a standardizing condition.

[0024]

According to the image processing condition determining method and apparatus of the present invention, image processing conditions can be determined using not only the part but also subject information representing the physical characteristics of the subject as information indicating individual differences. Since the determination is made, the interpretation performance of the image that has been subjected to the image processing based on the determined image processing conditions is not affected by differences in physique and the like, and does not need to be re-tuned by an operator command. Also, an image suitable for image interpretation can always be obtained. Thereby, it is possible to reduce the trouble of re-adjusting the image processing conditions according to individual differences such as physique.

Further, various kinds of information such as feature amounts obtained by analyzing a medical image can be conveniently used as subject information indicating physical characteristics (individual differences) of the subject.

[0026]

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

FIG. 1 is a block diagram of an image processing apparatus provided with an embodiment of the image processing condition determining apparatus according to the present invention, and FIG. 2 is a block diagram showing a configuration of a medical network system provided with the image processing apparatus.

In the system shown in FIG. 2, a radiographic image of a patient is accumulated and recorded on an imaging plate (accumulative phosphor sheet) IP having an accumulative phosphor by an imaging device 10 provided in each imaging room. The stored and recorded radiation image is read by a reading device 30 provided in a reading room near the imaging room, and a desired image process such as a gradation process or a frequency enhancement process is performed on the image obtained by reading the image process in the image processing device 40. The processed image is displayed (soft copy) on an image display means 39 such as a CRT, and the image data is temporarily stored in a file server 50 as an image storage means via a network 90.
The image data is read out from the device and output as a hard copy to a film or the like by the image recording device 60 using a laser scanner or the like, and the image diagnosis is performed by the image diagnostic device 70.

As shown in FIG. 1, the image processing device 40
A part information obtaining unit 41 for obtaining part information indicating a part of a subject to be imaged; and input image data D1
A feature value obtaining means 42 as subject information obtaining means for analyzing the image data to obtain a predetermined feature value; an image processing condition determining means 43 for determining image processing conditions based on the obtained part information and the feature value; And image processing means 44 for performing image processing on the input image data D1 according to the set conditions to obtain processed image data D5. An image processing condition determining device 49 of the present invention is configured by the part information obtaining unit 41, the feature amount obtaining unit 42, and the image processing condition determining unit 43.

Further, as shown in FIG.
Is an identification information input device (ID terminal) 20 for reading an ID card on which patient identification information for identifying a patient, an imaging menu indicating an imaging site, and the like are recorded, and an image plate is read to acquire image data D1. A reading device 30 for inputting the image data D1 to the image processing device 40 and an image display means 39 for displaying and outputting a visible image based on the processed image data D5 are connected, and various information read by a card reader are connected. Is input to the reading device 30, and the information J1 indicating the imaging part of the various information is input to the image processing device 40. The reading device 30, the image processing device 40, or the image display unit 3
9 may be integrated in any combination.

The reading device 30 scans an imaging plate IP, on which a transmitted radiation image of a subject is stored and stored as energy information, with a laser beam as excitation light, and emits light with an amount of light corresponding to the stored energy. A CR (Computed Radiography) device that obtains a transmitted radiation image of a subject as a digital image by photoelectrically reading emitted light, and is widely used in medical institutions such as hospitals.

The reading device 30 receives a detection result J2 of transmitted radiation detected by a photo timer (not shown) provided in the photographing device 10 and information J3 on tube voltage of a not-shown radiation source. .

The image diagnostic apparatus 70 is disclosed in, for example,
As disclosed in Japanese Patent No. 79, there is provided an image display means such as a CRT, which has both functions of the whole image display means and the local image display means, and is provided with an abnormal shadow detection algorithm based on morphological processing. An apparatus that detects a shadow candidate of a calcified portion (hereinafter, referred to as a microcalcification shadow candidate) and detects a shadow candidate of a tumor portion (hereinafter, referred to as a tumor shadow candidate) by an abnormal shadow detection algorithm based on iris filter processing, A whole image showing the whole radiographic image of the subject, a whole image with a sign,
And an image of a local region (hereinafter, referred to as a local image) including an abnormal shadow candidate such as a microcalcification shadow candidate or a tumor shadow candidate detected based on digital image data representing the entire image (hereinafter, referred to as overall image data). This is an apparatus that displays a processed local image that has been subjected to a predetermined image enhancement process on an image display means in a predetermined layout.

A digital image acquired by the reading device 30 is provided between the reading device 30 and the network 90.
Before storing in the file server 50, the image is displayed on a display medium such as a CRT monitor to check the image quality such as image density and contrast, and check the shooting range and the like.
A WS (work station for checking image quality) may be provided.

Next, the operation of the system having the above-described configuration will be outlined.

The ID information of the patient is recorded on the ID card by an ID card writing device provided at a reception desk of a hospital or the like.

The patient receives the ID card and receives a diagnosis and a medical inquiry from a doctor in a predetermined medical department. An imaging menu such as an imaging part and an imaging direction is determined according to the result of the diagnosis and the inquiry, and the imaging menu information is additionally recorded (added) on the ID card.

Next, the patient goes to the radiology department and hands the ID card to a radiologist waiting in the reading room. Radiologist I
Read the D card with a card reader. The read ID information and the photographing menu information are displayed on a display panel (not shown). Further, part information J1 indicating the part to be photographed in the read photographing menu information is input to the part information acquiring means 41 of the image processing device 40.

The radiologist reads the barcode of the imaging plate IP for radiography with a barcode reader.
This makes the imaging plate IP used for photography
Can be associated with the patient and the imaging menu.

The radiologist who has confirmed the display stores and records a medical image to be processed by the image processing apparatus 40 on the imaging plate IP as follows. First,
The imaging plate IP is disposed between the radiation source 12 and the photo timer 15 so that the recording surface of the imaging plate IP faces the radiation source 12.
An object 9 to be imaged is arranged between the source 12 and the imaging plate IP such that the imaging site is located at the center of the imaging plate IP. Radiation is emitted from source 12. The radiation passes through the subject 9 and enters the imaging plate IP, and further passes through the imaging plate IP and enters the photo timer 15. As a result, the transmitted radiation image of the subject 9 is stored and recorded as energy information in the imaging plate IP according to the dose of the radiation transmitted through the subject 9.

Next, the radiologist sets the imaging plate I
P is loaded into the imaging device 10, and a radiation image of the patient is captured. After this imaging, the reading device 30 reads the imaging plate IP in which the transmitted radiation image of the patient is stored and recorded as energy information, thereby acquiring the transmitted radiation image as a digital image.

The obtained image data D1 carrying the digital image is input to the image processing device 40 and subjected to predetermined image processing. The processed image is displayed on the image display means 39 and output to the network 90. You.

Here, in the image processing apparatus 40, the image treatment condition determining means 43 has the part information J 1 obtained by the part information obtaining means 41 and the characteristic amount obtained by analyzing the image data D 1 by the characteristic amount obtaining means 42. , Image processing conditions for the input image data D1 (hereinafter also referred to as image processing conditions) are determined, and the determined image processing conditions are set in the image processing means 44. The image processing means 44 performs image processing according to the set image processing conditions. As described above, the image processing apparatus 40 is configured to determine (control) the image processing condition according to the photographing part, which is the target part of the subject, and the feature amount obtained by analyzing the image data D1. Here, the difference in the feature amount obtained by analyzing the image data D1 indicates the difference in the state of the part, that is, the individual difference, as described later. An image suitable for diagnosis is always obtained without being affected by (individual differences). Hereinafter, the operation of the image processing device 40 will be specifically described.

First, a case where the photographing apparatus 10 performs mammography photographing and the obtained image is used for diagnosing a breast cancer or the like will be described. In this case, the part information obtaining means 41 obtains that the imaging part is a breast from the part information J1 input from the identification information input device 20.

According to the investigation by the present inventors, in mammography, an image of a breast having a large amount of mammary glands tends to be a blurred image having less sharpness than an image of a breast having a small amount of mammary glands. It turns out.

On the other hand, when the amount of the mammary gland is different, it has been found that the frequency of the low density data increases as the amount of the mammary gland (dens breast) increases as the image data. That is, the amount of the mammary gland (individual difference) can be determined by using the cumulative histogram.

FIG. 3 shows an example of a method for determining the amount of the mammary gland using the cumulative histogram. When the frequency of the histogram is cumulatively added from the low-density side, when the amount of the mammary gland is large, that is, when the frequency of the low-density data is large, the cumulative value increases quickly, and the shape rises quickly as shown by the solid line in the figure. Become. On the other hand, when the amount of the mammary gland is small, on the other hand, as shown by the dotted line in the figure, the shape becomes slow rising.

Thus, when the signal value Dx having the predetermined cumulative frequency (x%) is closer to the low density side as shown by Da in the figure, the amount of the mammary gland is large, and as shown by Db in the figure, the high density is high. If it is closer to the side, it can be determined that the amount of mammary gland is small.

Therefore, the input image data D1 is subjected to a cumulative histogram analysis by the characteristic amount obtaining means 42, and a predetermined cumulative frequency (x% ) Is obtained, and the signal value Dx (feature amount J4) is input to the image processing condition determining means 43.

The image processing condition determining means 43 compares the input signal value Dx with a reference value determined in advance so as to correspond to, for example, a large, medium or small amount of the mammary gland, and reduces the signal value Dx.・ Classify into medium and large. Then, the small signal value Dx
The image processing conditions are determined so that the degree of enhancement of the frequency enhancement processing is high, medium, or low in accordance with medium / large, that is, the signal of the cumulative histogram corresponding to the amount of the mammary gland as the image processing condition for the breast. By preparing three emphasis levels corresponding to the value Dx (predetermined stage) in advance and selecting a condition corresponding to the actual signal value Dx from the prepared three emphasis levels,
An image processing condition corresponding to the signal value Dx is determined.

As a result, even if the image of the breast has a large amount of mammary glands, the sharpness of the processed image can be improved, and the image can be easily diagnosed. In other words, when the preferred image processing conditions according to the breast as the part and the amount of the mammary gland are automatically set, an image suitable for image reading ability can be always obtained, and the image processing conditions are readjusted according to the difference in the amount of the mammary gland. There is no need.

In determining the image processing conditions, a standard emphasis degree, which is a standard condition for the breast, is set in advance, and the amount of the mammary gland is smaller in the case of the image of the breast having a larger amount of the mammary gland. The standard emphasis level set for the breast is further continuously adjusted according to the signal value Dx (feature amount J4) in a direction in which the emphasis degree of the frequency emphasis processing is stronger than that of the case of the breast image. You may.

In the above embodiment, the mammography in which the breast is the subject has been described as an example, but the subject is not limited to the breast. For example, in the case of a chest X-ray image having a chest (lung field) as a subject, according to the investigation by the present inventors, an image of a fat person has an image with lower contrast than an image of a normal person. It was found that the degree of emphasis needed to be increased. Also, as shown in FIG. 4 (A), a fat person compresses the diaphragm with fat, so that the area ratio of the lung field occupied on the image is smaller than that of a normal person image, and the fat density is high. It was found that the cumulative histogram accumulated from the side is as shown in FIG. 4B, that is, whether or not it is fat (individual difference) can be determined by the cumulative histogram. Therefore, as in the case of the mammography, the signal value Dx having a predetermined cumulative frequency (x%) is obtained.
The signal value Dx (feature amount J4) is input to the image processing condition determining means 43, and the standard enhancement degree set for the chest X-ray image is further continuously adjusted according to the signal value Dx. Thus, image processing conditions can be determined.

In the above embodiment, the histogram analysis of the image data D1 is performed to obtain the characteristic amount J4 representing the difference in the distribution of the histogram. However, the characteristic amount usable in the present invention is not necessarily the one of the above embodiment. Not limited to

For example, there is a certain relationship between the S value which is an index indicating reading sensitivity obtained by analyzing the image data D1 and the L value which is an index indicating latitude, and the finally obtained image. For example, a large S value means that the transmission X
It indicates that the dose is small, and the image tends to be an image having a low contrast and a large amount of noise. On the other hand, a small L value indicates that the contrast is large, and it is desirable to weaken the degree of frequency emphasis. That is, by using the S value or the L value as the feature amount J4, it is possible to automatically set an appropriate image processing condition according to an image (individual difference).

Next, a case where an S value or an L value is used as the feature value J4 will be described as a second embodiment. Although not shown, in the case of the second embodiment, the feature amount acquisition unit 4
Reference numeral 2 is incorporated in a part of the reading device 30 that performs the EDR process.

In the CR device as the reading device 30, an EDR that determines reading conditions such as an S value as an index representing reading sensitivity and an L value as an index representing latitude is determined.
A "reading sensitivity / contrast adjusting function (normalization processing)" called processing is employed. In this EDR processing, as disclosed in, for example, Japanese Patent Application Laid-Open No. 58-67240 by the applicant of the present invention, pre-reading is performed prior to main reading, and reading such as reading sensitivity (S value) and latitude (L value) is performed. Method for determining conditions and Japanese Patent Application Laid-Open
As disclosed in, for example, -108175, the optimum reading sensitivity (S value) and latitude (L value) are obtained from image data obtained by main reading without performing pre-reading.
There is a method of converting the obtained image data into image data equivalent to image data obtained when an image is read again with these reading sensitivity and latitude based on these reading sensitivity and latitude. In particular, the method according to the above method is referred to as “normalization processing”, and the conversion processing conditions (reading conditions) at that time are referred to as “normalization conditions”.

First, a method of determining read conditions, that is, S values and L values by performing pre-read will be described.

Prior to the actual reading (the actual reading), the EDR image data and the patient ID obtained by performing the pre-reading in which the imaging plate IP is roughly scanned with a weak laser beam are read.
First, a divided photographing pattern is recognized from the photographing menu information input when the information is registered, and an area within the irradiation field aperture is extracted for each divided area. Next, a density histogram in the recognized X-ray irradiation field is created. As shown in FIG. 5, the histogram has a unique pattern for each imaging menu determined by the imaging region and the imaging method. Utilizing this property, the maximum value S ₁ and the minimum value S of the effective image data
_{If 2} is detected, the reading conditions for the main reading can be determined so that the image density / contrast becomes uniform.

As described above, the reading condition is the reading sensitivity (S
Value) and latitude (L value), which determine the sensitivity of the photomultiplier (photomultiplier tube) and the gain of the amplifier. The image data obtained by performing the main reading under the reading conditions determined in this way is always normalized to a constant digital value regardless of what subject is photographed by any technique.

Next, the EDR processing will be described in detail with reference to FIG.

The first quadrant shows the relationship between the amount of X-rays applied to the imaging plate IP and the stimulating luminescence intensity. This is one of the notable features of the imaging plate IP, and a stimulable luminescence intensity proportional to the incident X-ray dose can be obtained over a wide range of incident X-ray dose.

The second quadrant expresses the relationship between the EDR processing, that is, the stimulating luminescence intensity as an input to the reading unit and the output digital signal obtained by reading under the reading conditions determined by the EDR processing. .

The third quadrant shows image enhancement processing (frequency processing, gradation processing, etc.) for converting into display characteristics suitable for diagnosis. This figure shows an example of a gradation processing curve suitable for mammography imaging.

The fourth quadrant shows a characteristic curve of an output photograph in a CR system (computed radiography system). Specifically, the horizontal axis indicates the incident X-ray dose, and the vertical axis indicates the film concentration, and is expressed in a form in which the characteristic curve of an X-ray photograph using a normal fluorescent screen / film system is inverted. I have.

As described above, in the EDR processing, the maximum value S ₁ and the minimum value S ₂ of the image signal effective for diagnosis are detected from the histogram of the EDR image data obtained by prefetching.
S ₁ and S ₂ are set in advance for each shooting menu and the value Q
Determining the reading conditions be converted to ₁ and Q _2.

That is, a high X-ray dose and a narrow image range
In the case of (i), (A) is an example (i
In the case of i), (B) is a reading condition determined by the EDR process. As a result, the characteristic curve of the CR system changes arbitrarily in accordance with the amount of X-ray and the size of the image range, so that stable image density and contrast can always be realized. In other words, regardless of the amount of X-ray dose and the size of the image range, the finally obtained image data can be normalized to a certain value. This is a significant difference from the characteristic curve of the conventional screen / film system.

As described above, the reading conditions in the CR device are defined by the two parameters of the reading sensitivity (S value) and the latitude (L value), and the reading conditions for the image data can be known from these two indices. FIG. 7 shows the relationship between the reading sensitivity (S value) and the latitude (L value).
This will be described with reference to FIG. The S value, which is an index representing the reading sensitivity, is calculated by using the value Sk representing the amount of stimulated emission of the imaging plate IP corresponding to the median value of digital pixels (511 in the case of 10 bits), as follows: ).

(Equation 1)

Here, the value Sk representing the amount of stimulated light emission is defined as a light emitting amount obtained when 20 mR (= 5.16 × 10 ^-6 C / kg) is irradiated at a tube voltage of 25 kVp of the Mo tube as a reference value 3.0. It is a logarithmic scale. When the Sk value is the reference value 3.0, the S value is 40. It can be seen that the Sk increases as the X-ray irradiation amount relatively increases, and the S value decreases accordingly. This means that a sufficient signal can be extracted even if the reading sensitivity (S value) is low because the amount of stimulated emission from the imaging plate IP is large.

On the other hand, the L value is an index indicating how many digits of the stimulating light emission amount of the imaging plate IP is to be digitized around the Sk value, and the characteristic values S ₁ and S ₂ detected in the EDR processing. And the corresponding pixel values Q ₁ and Q ₂ are defined by the following equation (3).

(Equation 2)

For example, when signals having the same contrast in terms of X-ray energy are read separately at L value = 1 and L value = 2, L value = 1 is 2 digitally greater than L value = 2.
Will have a double difference.

The reading conditions determined by the EDR processing, that is, the S value and the L value, are determined with a primary focus on realizing the density and contrast suitable for image reading. For example, an image with a narrow dynamic range is actively controlled to increase the contrast so that the image is easily read. The above are the S value and the L value which are the reading conditions determined by the EDR processing.

Next, a method of performing the EDR processing without performing the prefetch will be described.

In the above-described EDR processing for prefetching,
The outline of the radiation image information stored and recorded on the imaging plate IP is read by the pre-reading. However, when the pre-reading is not performed, the outline of the radiation image information is not known. The detection range for detecting is set sufficiently wide. Thereby, the entire radiation image information can be read, and based on the image data obtained by reading,
As in the case of performing the pre-reading described above, two parameters, ie, reading sensitivity (S value) and latitude (L value), which are reading conditions for obtaining an optimal reproduced image, are obtained. Then, the obtained reading sensitivity (S value) and latitude (L
The image data D1 obtained by the main reading may be converted according to the standardization condition corresponding to (value).

In this conversion process, a conversion table is created based on the obtained reading sensitivity (S value) and latitude (L value), and all image data D1 are converted based on the conversion table. What should I do?

The S value obtained by the EDR process is input to the image processing condition determining means 43 of the image processing device 40 as the feature amount J4.

On the other hand, as described above, the S value (reading sensitivity)
Image processing condition determining means 43, based on the S value and the L value input as one mode of the feature amount J4, since there is a certain relationship between the image and the L value (lattice) and the image. An image processing condition corresponding to the relationship is determined.

For example, when the S value is large, the image tends to have a low contrast and a lot of noise, so that the low-frequency band including a tumor shadow or the like is emphasized, and the high-frequency band including a noise is not emphasized much. Alternatively, an image processing condition to be suppressed is set.

When the L value is small, the contrast is large, so that the image processing condition for weakening the frequency emphasis level is set. On the other hand, when the L value is large, the contrast is small, so the image processing condition for increasing the frequency emphasis degree is set.

Although the preferred embodiment of the present invention in which the image processing condition is determined according to the region and the individual difference between the objects has been described above, the information indicating the individual difference between the objects is not limited to the above embodiment. , And other information can also be used.

For example, as an index (feature amount) indicating whether or not a person is fat, an obesity degree calculated based on height and weight obtained from patient information can be used. In this case, the image processing condition may be set such that the degree of emphasis increases as the degree of obesity increases.

If the result after image processing tends to be different depending on the gender of the patient (gender difference), the image processing condition may be set according to the gender, and according to the age of the patient. If the result after the image processing tends to be different, the image processing condition may be set according to the age.

[Brief description of the drawings]

FIG. 1 is a block diagram of an image processing apparatus provided with an embodiment of an image processing condition determining apparatus according to the present invention.

FIG. 2 is a block diagram showing a configuration of a medical network system including the image processing device shown in FIG.

FIG. 3 is a diagram showing an example of a cumulative histogram in mammography image data.

FIG. 4 is a view showing an example of a cumulative histogram in image data of a chest X-ray image;

FIG. 5 is a density histogram in an X-ray irradiation field.

FIG. 6 is a diagram showing the operating principle of EDR processing;

FIG. 7 is a diagram for explaining the relationship between reading sensitivity (S value) and latitude (L value), which are reading conditions.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Imaging device 20 Identification information input device 30 Reading device 39 Image display means 40 Image processing device 41 Part information acquisition means 42 Feature amount acquisition means 43 Image processing condition determination means 44 Image processing means 49 Image processing condition determination apparatus 50 File server 60 Image Recording device 70 Image diagnostic device 90 Network

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Takeshi Okubo Takeshi 798- Address, Miyagi, Kaisei-cho, Ashigara-gun, Kanagawa F-Term (in reference) 4C093 AA01 AA26 CA01 CA21 DA06 FA47 FD03 FD05 FF15 FF18 FF28 5B057 AA08 BA03 CA02 CA08 CA12 CA16 CB02 CB08 CB12 CB16 CC01 CH18 DA02 DB02 DB05 DB09 DC23 DC36 5L096 AA03 AA06 BA06 BA13 DA01 FA37 JA11

Claims (10)

[Claims] 1. An image processing condition determining method for determining image processing conditions to be applied to a medical image obtained by capturing an image of a subject, wherein the method includes determining a part of the subject and subject information representing a physical characteristic of the subject. Determining an image processing condition based on the image processing condition. 2. The image processing conditions are determined by adjusting standard image processing conditions set for each part of the subject based on the subject information.
Alternatively, the image processing is performed by selecting image processing conditions according to the subject information of the photographed subject from among a large number of image processing conditions set for each part of the subject and each subject information. The method for determining image processing conditions according to claim 1. 3. The image processing condition determining method according to claim 1, wherein when the part of the subject is a breast, the subject information indicates an amount of a mammary gland. 4. The image processing condition determining method according to claim 1, wherein the subject information is a feature amount obtained by analyzing an acquired medical image. 5. The method according to claim 1, wherein the characteristic amount represents a reading condition.
5. The method according to claim 4, wherein the method represents a normalization condition. 6. An image processing condition determining apparatus for determining image processing conditions to be applied to a medical image obtained by capturing an image of a subject, comprising: a site information obtaining unit configured to obtain site information indicating a site of the subject; Subject information obtaining means for obtaining subject information representing physical characteristics of the subject; image processing condition determining means for determining the image processing conditions based on the obtained part information and the obtained subject information An image processing condition determining apparatus comprising: 7. The image processing condition determining means determines the image processing condition by adjusting a standard image processing condition set for each part of the subject based on the subject information, or By selecting an image processing condition according to the subject information of the photographed subject from among a large number of image processing conditions set for each of the parts of the subject and for each of the subject information, 7. The image processing condition determining apparatus according to claim 6, wherein the determination is performed. 8. A method according to claim 1, wherein said subject information obtaining means obtains, as said characteristic amount, information representing a mammary gland amount when said part information regarding a breast as said part of said subject is obtained. Item 6. The image processing condition determining apparatus according to Item 6 or 7. 9. The apparatus according to claim 6, wherein the subject information acquiring unit uses a feature amount obtained by analyzing the acquired medical image as the subject information. Image processing condition determination device. 10. The image processing condition determining apparatus according to claim 9, wherein the characteristic amount represents a reading condition or a standardization condition.