JP4489272B2 - Filter processing apparatus and MRI apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a filter processing method, a filter processing apparatus, an MRI apparatus, and software. More specifically, the present invention is good for an enlarged data array in which interpolation data is added between original data of the original data array to increase the number of data. The present invention relates to a filter processing method, a filter processing apparatus, an MRI apparatus, and software capable of performing filter processing.
[0002]
[Prior art]
In the MRI apparatus, a desired matrix size such as 128 × 128 or 256 × 256 can be selected at the time of imaging. On the other hand, when the captured image is stored, it is standardized to a fixed matrix size of, for example, 256 × 256 or 512 × 512 for the convenience of management and processing. For this reason, when the matrix size at the time of imaging is smaller than the storage matrix size, interpolation processing is performed and interpolation data is added between the original data.
[0003]
FIG. 22 is a conceptual diagram of a matrix size data array during imaging.
Black circles represent the original data. This data array is generally called an original data array.
[0004]
FIG. 23 is a conceptual diagram of a data array in which interpolation data is added between original data and the matrix size is enlarged for storage.
White circles represent interpolation data. This data array is generally called an enlarged data array.
[0005]
Conventionally, when a filter process is applied to an enlarged data array, the filter process is executed on the enlarged data array to obtain a filtered enlarged data array as shown in FIG.
The black square represents the original data after the filtering process, and the white square represents the interpolation data after the filtering process.
Note that the filter processing is, for example, smoothing processing, edge enhancement processing, variance value processing, or the like.
[0006]
[Problems to be solved by the invention]
The problems of the prior art will be described with reference to FIGS. For simplification of description, the data array is assumed to be a one-dimensional array and the filtering process is assumed to be a smoothing process.
As shown in FIG. 25, in the original data array, the data at odd positions takes the value L, and the data at even positions takes the value H.
As shown in FIG. 26, an enlarged data array is obtained by adding interpolation data having their average values to the intermediate positions of adjacent original data.
FIG. 27 shows that when there is adjacent data on only one side of the data to be smoothed with respect to the enlarged data array of FIG. 26, the data to be smoothed is multiplied by a weight of 0.5 and the weight of the adjacent data is 0.5. When there is adjacent data on both sides of the data to be smoothed, the data to be smoothed is multiplied by a weight of 0.5 and the adjacent data is multiplied by a weight of 0.25 and added. It is the expansion data array of the result of having performed the smoothing process which takes a value.
[0007]
However, when the same smoothing process is performed on the original data array, it becomes as shown in FIG.
[0008]
As can be seen from a comparison between FIG. 27 and FIG. 28, when the filter process is applied to the enlarged data array, a satisfactory processing result is not obtained.
As described above, the conventional filter processing for the enlarged data array has a problem that a satisfactory processing result cannot be obtained.
Accordingly, an object of the present invention is to provide a filter processing method, a filter processing apparatus, an MRI apparatus, and software capable of performing good filter processing on an enlarged data array.
[0009]
[Means for Solving the Problems]
In a first aspect, the present invention is a filtering method for an enlarged data array in which the number of data is expanded by adding interpolation data between the original data of the original data array, and the original data and the interpolation data in the original data array The data is rearranged so as to be separated and collected, the filtered processing is executed on the rearranged enlarged data array, and the data of the filtered extended data array is restored to the original position. A filtering method is provided.
In the conventional filter processing, since the filter processing is performed on the original data and the interpolation data that are evenly mixed and interpolated, it is considered that good filter processing results cannot be obtained due to the side effect of the interpolation data. It is done.
On the other hand, in the filtering method according to the first aspect, the data is rearranged so that the original data and the interpolation data are separately gathered and positioned, and the filtering process is executed on this. Then, since the original data and the interpolation data are not mixed, the filter processing result is good. Then, since the data is returned to the original position after the filtering process, an enlarged data array subjected to a favorable filtering process is obtained.
[0010]
In a second aspect, the present invention is a filtering method for an enlarged data array in which interpolation data is added to the original data of the original data array to increase the number of data, and the size ratio of the enlarged data array to the original data array When an integer value close to R is I, (I-1) data is rearranged so as to be grouped for each piece of data, and filter processing is executed on the rearranged enlarged data array. Provided is a filter processing method characterized by restoring the data of the filtered expanded data array to the original position.
In the conventional filter processing, since the filter processing is performed on the original data and the interpolation data that are evenly mixed and interpolated, it is considered that good filter processing results cannot be obtained due to the side effect of the interpolation data. It is done.
On the other hand, in the filtering method according to the second aspect, the data is rearranged so that the probability that the original data and the interpolation data are separately gathered and positioned is increased, and the filtering process is performed on this. Execute. Then, since the original data and the interpolation data are not mixed, the filter processing result is good. Then, since the data is returned to the original position after the filtering process, an enlarged data array subjected to a favorable filtering process is obtained.
[0011]
In a third aspect, the present invention provides a filtering method according to the above-described configuration, wherein the data is not rearranged if the size ratio of the enlarged data array to the original data array is 1.7 or less. provide.
According to the knowledge of the inventors of the present invention, when the size ratio of the enlarged data array to the original data array is 1.7 or less, no particular difference from the conventional filter processing method is obtained.
Therefore, in the filter processing method of the third aspect, when the size ratio of the enlarged data array to the original data array is 1.7 or less, the data is not rearranged, and the processing burden of rearrangement and restoration is avoided.
[0012]
In a fourth aspect, the present invention provides the filtering method of the above configuration, wherein the original data array and the enlarged data array are two-dimensional arrays, and the size ratio Rx and y direction in the x direction of the enlarged data array with respect to the original data array Integer ratios Ix and Iy that are close to the size ratio Ry are obtained, and the data is rearranged so as to be grouped for each (Ix-1) jump in the x direction of the enlarged data array, or ( Iy-1) rearrange the data so as to be grouped for each piece of data located in the jump, and then rearrange the data so as to be gathered for each piece of data located in the direction of (Iy-1) pieces, or x The data is rearranged so as to be grouped for each (Ix-1) pieces of data in the direction, and the filter processing is executed on the rearranged enlarged data array. To provide a filter processing method characterized by restoring the data of a large data array to the original position.
In the filter processing method according to the fourth aspect, an enlarged data array subjected to good filter processing can be obtained when the enlarged data array is a two-dimensional array. That is, good filter processing can be performed on the image data.
[0013]
In a fifth aspect, the present invention provides the filtering method of the above configuration, wherein the original data array and the enlarged data array are three-dimensional arrays, and the size ratios Rx and y directions in the x direction of the enlarged data array with respect to the original data array The size ratio Ry and the size ratio Rz in the z direction and the integer ratios Ix, Iy, and Iz that are close to the size ratio are obtained, and are collected for each piece of data that is located at (Ix-1) skips in the x direction of the enlarged data array The data is rearranged, and then the data is rearranged so as to be collected for each data located in the (Iy-1) jumps in the y direction, and then the (Iz-1) jumps in the z direction of the enlarged data array. The data is rearranged so as to be organized for each position data, the filtered processing is executed on the rearranged enlarged data array, and the data of the filtered extended data array is converted to the original data. To provide a filter processing method characterized by restoring the location.
In the filter processing method according to the fifth aspect, when the enlarged data array is a three-dimensional array, an enlarged data array subjected to good filter processing is obtained. That is, a good filter process can be performed on the volume data.
[0014]
In a sixth aspect, the present invention is a filter processing apparatus for an enlarged data array in which the number of data is expanded by adding interpolation data between the original data in the original data array, and the original data and the interpolation data in the original data array The data rearrangement means for rearranging the data so as to be divided into pieces, the filter execution means for executing the filtering process on the rearranged enlarged data array, and the data array of the filtered enlarged data array There is provided a filter processing device characterized by comprising data array restoring means for returning to (1).
In the filter processing apparatus according to the sixth aspect, the filter processing method according to the first aspect can be suitably implemented.
[0015]
In a seventh aspect, the present invention is a filter processing apparatus that performs a filtering process on an enlarged data array in which interpolation data is added between original data in an original data array to expand the number of data. Array size ratio obtaining means for obtaining the size ratio of the enlarged data array, integer ratio obtaining means for obtaining the integer ratio I based on the size ratio, and (I-1) data so as to be collected for each piece of data Data rearranging means for rearranging, filter processing executing means for executing filter processing on the rearranged enlarged data array, and data array restoring means for restoring the data array of the filtered enlarged data array A filter processing apparatus characterized by the above is provided.
In the filter processing apparatus according to the seventh aspect, the filter processing method according to the second aspect can be suitably implemented.
[0016]
In an eighth aspect, the present invention provides the filter processing device having the above configuration, wherein when the size ratio of the enlarged data array to the original data array is 1.7 or less, the filter processing execution means The filter processing device is characterized in that the filter processing is executed.
In the filter processing apparatus according to the eighth aspect, the filter processing method according to the second aspect can be suitably implemented.
[0017]
According to a ninth aspect, in the filter processing device having the above-described configuration, when the original data array and the enlarged data array are two-dimensional arrays, the size ratios Rx and y in the x direction of the enlarged data array with respect to the original data array are provided. An array size ratio acquisition unit for obtaining a size ratio Ry for the direction, a size ratio Rx for the x direction of the enlarged data array relative to the original data array, and an integer ratio for obtaining an integer ratio Ix and Iy close to the size ratio Ry for the y direction The data is rearranged so as to be collected for each of the acquisition means and (Ix-1) jumps in the x direction of the enlarged data array, and then for each data located in the (Iy-1) jumps in the y direction. Data rearranging means for rearranging the data so that they are collected together, and a filter processing execution unit for executing filter processing on the rearranged enlarged data array If, to provide a filter processing apparatus characterized by comprising a data sequence restoring means to restore the sequence of data of the enlarged data sequences filtering.
In the filter processing apparatus according to the ninth aspect, the filter processing method according to the fourth aspect can be suitably implemented.
[0018]
In a tenth aspect, according to the present invention, in the filter processing device having the above configuration, when the original data array and the enlarged data array are three-dimensional arrays, the size ratios Rx, y in the x direction of the enlarged data array with respect to the original data array Array size ratio acquisition means for obtaining a size ratio Ry for the direction and a size ratio Rz for the z direction, and a size ratio Rx for the x direction of the enlarged data array with respect to the original data array, a size ratio Ry for the y direction, and a z direction Integer ratio acquisition means for obtaining integer ratios Ix, Iy, and Iz that are close to the size ratio Rz, and rearrange the data so as to be grouped for each (Ix-1) skips in the x direction of the enlarged data array Next, the data is rearranged so as to be collected for each of the (Iy-1) pieces of data in the y direction, and then (Iz-1 Data rearranging means for rearranging the data so as to be grouped for each piece of data located in a discrete manner, filter processing executing means for executing filter processing on the rearranged enlarged data array, and There is provided a filter processing apparatus comprising a data arrangement restoring means for restoring the data arrangement.
In the filter processing apparatus according to the tenth aspect, the filter processing method according to the fifth aspect can be suitably implemented.
[0019]
In an eleventh aspect, the present invention provides an MRI apparatus comprising the filter processing apparatus having the above-described configuration.
In the MRI apparatus according to the eleventh aspect, MR image data and MR volume data can be satisfactorily filtered.
[0020]
In a twelfth aspect, the present invention is software for performing filtering on an enlarged data array in which interpolation data is added between original data in the original data array to expand the number of data, and the original data array A step of obtaining an integer value I close to the size ratio R of the enlarged data array to (I-1), a step of rearranging the data so as to be gathered for each piece of data located in a jump, and the rearranged enlarged data array There is provided software characterized by including a step of executing filtering processing and a step of restoring the data arrangement of the filtered enlarged data arrangement.
With the software according to the twelfth aspect, the filter processing method according to the second aspect can be suitably implemented.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in more detail with reference to embodiments shown in the drawings. Note that the present invention is not limited thereby.
[0022]
-First embodiment-
FIG. 1 is a block diagram showing an MRI apparatus according to the first embodiment of the present invention.
In the MRI apparatus 100, the magnet assembly 1 has a space portion (bore) for inserting the subject therein, and a static magnetic field that applies a constant static magnetic field to the subject so as to surround the space portion. Gradient for generating the coil 1p and gradient magnetic fields of the X, Y, and Z axes (a slice gradient axis, a lead gradient axis, and a phase encode gradient axis are formed by a combination of the X, Y, and Z axes) A magnetic field coil 1g, a transmission coil 1t that applies an RF pulse for exciting spins of nuclei in the subject, and a reception coil 1r that detects an NMR signal from the subject are arranged. The static magnetic field coil 1p, gradient magnetic field coil 1g, transmission coil 1t and reception coil 1r are connected to a static magnetic field power source 2, a gradient magnetic field drive circuit 3, an RF power amplifier 4 and a preamplifier 5, respectively.
[0023]
The sequence storage circuit 6 operates the gradient magnetic field driving circuit 3 based on the stored pulse sequence in accordance with a command from the computer 7 to generate a gradient magnetic field from the gradient magnetic field coil 1g of the magnet assembly 1 and gate modulation. The circuit 8 is operated, and the carrier wave output signal of the RF oscillation circuit 9 is modulated into a pulse signal having a predetermined timing and a predetermined envelope shape, which is added as an RF pulse to the RF power amplifier 4 and power amplified by the RF power amplifier 4 Thereafter, it is applied to the transmission coil 1t of the magnet assembly 1 to selectively excite a desired imaging surface.
[0024]
The preamplifier 5 amplifies the NMR signal from the subject detected by the receiving coil 1 r of the magnet assembly 1 and inputs it to the phase detector 10. The phase detector 10 uses the carrier wave output signal of the RF oscillation circuit 9 as a reference signal, phase-detects the NMR signal from the preamplifier 5, and provides it to the A / D converter 11. The A / D converter 11 converts the analog signal after phase detection into digital data and inputs the digital data to the computer 7.
[0025]
The computer 7 reads the digital data from the A / D converter 11 and performs image reconstruction calculation to generate an original data array of MR images having a matrix size of 256 × 256, for example. Further, the computer 7 performs an interpolation process on the original data array, and stores it in the storage device 13 in a unified manner, for example, an enlarged data array of an MR image having a matrix size of 512 × 512. In addition, the computer 7 performs a filtering process on the enlarged data array. Further, the computer 7 is responsible for overall control such as receiving information input from the operation console 12.
The display device 14 displays the MR image subjected to the filtering process.
[0026]
2 and 3 are flowcharts of filter processing according to the first embodiment by the MRI apparatus 100. FIG.
The description will be made assuming an enlarged data array having a matrix size of 15 × 15 shown in FIG. The original data array from which the enlarged data array is based has a matrix size of 8 × 8. In FIG. 4, black circles represent original data, and white circles represent interpolation data.
[0027]
In Step P1, an x-direction size ratio Rx and a y-direction size ratio Ry of the enlarged data array with respect to the original data array are obtained. In the example of FIG. 4, Rx = 1.875 and Ry = 1.875.
In Step P2, it is checked whether or not the x-direction size ratio Rx ≦ 1.7. If Rx> 1.7, the process proceeds to Step P3. If Rx ≦ 1.7, the process proceeds to Step P5. In the example of FIG. 4, since Rx = 1.875, the process proceeds to Step P3.
In Step P3, an integer value Ix close to the x-direction size ratio Rx is obtained. In the example of FIG. 4, since Rx = 1.875, rounding is performed to obtain Ix = 2.
In step P4, the data of the enlarged data array is rearranged so as to be gathered for each data located in a distance of (Ix-1) in the x direction. In the example of FIG. 4, the data is rearranged in the x direction so as to be collected for each piece of data located in the x direction, and the enlarged data array of FIG. 5 is obtained.
[0028]
In Step P5, it is checked whether or not the y-direction size ratio Ry ≦ 1.7. If Ry> 1.7, the process proceeds to Step P6. If Ry ≦ 1.7, the process proceeds to Step P11. In the example of FIG. 4, since Ry = 1.875, the process proceeds to Step P6.
In Step P6, an integer value Iy close to the y-direction size ratio Ry is obtained. In the example of FIG. 4, since Ry = 1.875, rounding is performed to obtain Iy = 2.
In step P7, the data of the enlarged data array is rearranged so as to be gathered for each data located in a distance of (Iy-1) in the y direction. In the example of FIG. 5, the data is rearranged in the y direction so as to be collected for each piece of data positioned in the y direction so as to obtain the enlarged data array of FIG.
[0029]
In step P11, a filtering process is performed on the enlarged data array. In the example of FIG. 4, the filtering process is executed on the enlarged data array of FIG. 6 to obtain the enlarged data array of FIG. In FIG. 7, black squares represent original data after filtering, and white squares represent interpolation data after filtering.
[0030]
In step P23 of FIG. 3, it is checked whether the y-direction size ratio Ry ≦ 1.7. If Ry> 1.7, the process proceeds to step P24, and if Ry ≦ 1.7, the process proceeds to step P25. In the example of FIG. 4, since Ry = 1.875, the process proceeds to Step P24.
In step P24, the data rearranged in the y direction is restored. In the example of FIG. 7, the position in the y direction is restored as shown in FIG.
[0031]
In step P25, it is checked whether or not the x-direction size ratio Rx ≦ 1.7. If Rx> 1.7, the process proceeds to step P26, and if Rx ≦ 1.7, the process ends.
In step P26, the data rearranged in the x direction is restored. In the example of FIG. 8, the position in the x direction is restored as shown in FIG. Then, the process ends.
[0032]
The principle of the present invention will be described with reference to FIGS. For simplification of description, the data array is assumed to be a one-dimensional array and the filtering process is assumed to be a smoothing process.
As shown in FIG. 10, in the enlarged data array, the black circle original data alternately takes values L and H, and white circle interpolation data having their average value is added at an intermediate position between adjacent original data. . In this example, the size ratio R = 1.875.
FIG. 11 shows an enlarged data array obtained by rearranging the data of the enlarged data array shown in FIG. I = 2, and one rearranged data, that is, odd-numbered data and even-numbered data are rearranged so as to be collected separately.
FIG. 12 shows that when there is adjacent data on only one side of the smoothing target data with respect to the enlarged data array of FIG. 11, the smoothing target data is multiplied by a weight of 0.5 and the adjacent data is weighted by 0.5. When there is adjacent data on both sides of the data to be smoothed, the data to be smoothed is multiplied by a weight of 0.5 and the adjacent data is multiplied by a weight of 0.25 and added. It is the expansion data array of the result of having performed the smoothing process which takes a value.
FIG. 13 is an enlarged data array obtained by restoring data to the original position, that is, an enlarged data array obtained as a result of performing the filtering process of the present invention.
[0033]
If FIG. 13 according to the present invention is compared with FIG. 23 according to the prior art, it will be understood that the present invention can perform the filtering process better than the conventional one.
[0034]
The principle of the present invention will be further described with reference to FIGS. For simplification of description, the data array is assumed to be a one-dimensional array and the filtering process is assumed to be a smoothing process.
As shown in FIG. 14, in the enlarged data array, the original data of black circles alternately take values L and H, and two interpolation data of white circles and white oval are added between adjacent original data. . In this example, the size ratio R = 2.75.
FIG. 15 shows an enlarged data array obtained by rearranging the data of the enlarged data array shown in FIG. I = 3, and two rearranged data are rearranged so as to be collected separately.
FIG. 16 shows that when there is adjacent data on only one side of the data to be smoothed with respect to the enlarged data array of FIG. 15, the data to be smoothed is weighted by 0.5 and the weight of the adjacent data is 0.5. When there is adjacent data on both sides of the data to be smoothed, the data to be smoothed is multiplied by a weight of 0.5 and the adjacent data is multiplied by a weight of 0.25 and added. It is the expansion data array of the result of having performed the smoothing process which takes a value.
FIG. 16 shows an enlarged data array obtained by restoring data to the original position, that is, an enlarged data array obtained as a result of performing the filtering process of the present invention.
[0035]
It will be understood from FIGS. 14 to 17 that the filter process can be performed satisfactorily even when the size ratio R is 2.5 to 3.4. The same applies to a size ratio R larger than that.
[0036]
According to the MRI apparatus 100, it is possible to satisfactorily perform the filtering process on the MR image in which the matrix size is expanded by adding the interpolation data, and the image quality can be improved.
[0037]
-Second Embodiment-
18 and 19 are flowcharts of filter processing according to the second embodiment by the MRI apparatus 100. FIG.
In Step P1, the x-direction size ratio Rx, the y-direction size ratio Ry, and the z-direction size ratio Rz of the enlarged data array with respect to the original data array are obtained.
In Step P2, it is checked whether or not the x-direction size ratio Rx ≦ 1.7. If Rx> 1.7, the process proceeds to Step P3. If Rx ≦ 1.7, the process proceeds to Step P5.
In Step P3, an integer value Ix close to the x-direction size ratio Rx is obtained.
In step P4, the data of the enlarged data array is rearranged so as to be gathered for each data located in a distance of (Ix-1) in the x direction.
[0038]
In step P5, it is checked whether or not the y-direction size ratio Ry ≦ 1.7. If Ry> 1.7, the process proceeds to step P6. If Ry ≦ 1.7, the process proceeds to step P8.
In Step P6, an integer value Iy close to the y-direction size ratio Ry is obtained.
In step P7, the data of the enlarged data array is rearranged so as to be gathered for each data located in a distance of (Iy-1) in the y direction.
[0039]
In Step P8, it is checked whether or not the z-direction size ratio Rz ≦ 1.7. If Rz> 1.7, the process proceeds to Step P9, and if Rz ≦ 1.7, the process proceeds to Step P11.
In Step P9, an integer value Iz close to the z-direction size ratio Rz is obtained.
In Step P10, the data of the enlarged data array is rearranged so as to be collected for each data located in the z direction with (Iz-1) jumps.
[0040]
For example, when the steps P4, P7, and P10 are executed on the three-dimensional enlarged data array in FIG. 20, the original data (black circles) and the interpolation data (white circles) are separated as shown in FIG. The expanded data array is rearranged into
[0041]
In step P11, a filtering process is performed on the enlarged data array.
[0042]
In step P21 of FIG. 19, it is checked whether or not the z-direction size ratio Rz ≦ 1.7. If Rz> 1.7, the process proceeds to step P22. If Rz ≦ 1.7, the process proceeds to step P23.
In step P23, it is checked whether the y-direction size ratio Ry ≦ 1.7. If Ry> 1.7, the process proceeds to step P24. If Ry ≦ 1.7, the process proceeds to step P25.
In step P24, the data rearranged in the y direction is restored.
[0043]
In step P25, it is checked whether or not the x-direction size ratio Rx ≦ 1.7. If Rx> 1.7, the process proceeds to step P26, and if Rx ≦ 1.7, the process ends.
In step P26, the data rearranged in the x direction is restored. Then, the process ends.
[0044]
As described above, the present invention can also be applied when the enlarged data array is a three-dimensional array.
[0045]
【The invention's effect】
According to the filter processing method, filter processing apparatus, MRI apparatus, and software of the present invention, it is possible to satisfactorily perform filter processing on an enlarged data array in which the array size is expanded by adding interpolation data.
[Brief description of the drawings]
FIG. 1 is a block diagram of an MRI apparatus according to a first embodiment of the present invention.
FIG. 2 is a flowchart of filter processing according to the first embodiment of the present invention.
FIG. 3 is a flowchart continued from FIG. 2;
FIG. 4 is an exemplary diagram of a two-dimensional enlarged data array.
FIG. 5 is an exemplary view of an enlarged data array rearranged in the x direction.
FIG. 6 is an exemplary diagram of an enlarged data array rearranged in the y direction.
FIG. 7 is a view showing an example of an enlarged data array after performing a filtering process on the rearranged enlarged data array.
FIG. 8 is an exemplary diagram of an enlarged data array after filter processing in which the position of data in the y direction is restored.
FIG. 9 is an exemplary diagram of an enlarged data array after filter processing in which the position of data in the x direction is restored.
FIG. 10 is an illustration of an enlarged data array in which one piece of interpolation data is added between original data.
11 is a view showing an example of the enlarged data array of FIG. 10 rearranged. FIG.
12 is an exemplary diagram of an enlarged data array obtained by executing a smoothing process on the enlarged data array of FIG. 11;
13 is an exemplary diagram of an enlarged data array obtained by restoring the data position of FIG.
FIG. 14 is an exemplary diagram of an enlarged data array in which two interpolation data are added between original data.
15 is a view showing an example of the enlarged data array of FIG. 14 rearranged. FIG.
16 is an exemplary diagram of an enlarged data array obtained by executing a smoothing process on the enlarged data array of FIG. 15;
FIG. 17 is a view showing an example of an enlarged data array obtained by restoring the data position of FIG. 16;
FIG. 18 is a block diagram of an MRI apparatus according to a second embodiment of the present invention.
FIG. 19 is a flowchart of filter processing according to the second embodiment of the present invention.
FIG. 20 is a schematic diagram showing an enlarged data array of a three-dimensional array.
FIG. 21 is a schematic diagram showing an enlarged data array of a rearranged three-dimensional array.
FIG. 22 is a view showing an example of a two-dimensional original data array.
23 is an exemplary diagram of an enlarged data array in which one piece of interpolation data is added between the original data in FIG.
24 is a view showing an example of an enlarged data array obtained by performing filter processing on the enlarged data array of FIG. 23. FIG.
FIG. 25 is a view showing an example of a one-dimensional original data array.
26 is an exemplary diagram of an enlarged data array in which one piece of interpolation data is added between the original data in FIG. 25. FIG.
27 is a view showing an example of an enlarged data array obtained by performing a filtering process on the enlarged data array of FIG. 26. FIG.
28 is a view showing an example of an original data array obtained by executing a filtering process on the original data array of FIG.
[Explanation of symbols]
7 Calculator
13 Storage device
100 MRI system

Claims (5)

A filter processing device that performs a filtering process on an expanded data array in which the number of data is expanded by adding interpolation data between the original data of the original data array,
An array size ratio acquisition means for obtaining a size ratio of the enlarged data array to the original data array;
An integer ratio obtaining means for obtaining an integer ratio I based on the size ratio;
(I-1) data rearranging means for rearranging data so as to be grouped for each piece of data located in a jump;
Filter processing execution means for executing filter processing on the rearranged enlarged data array;
A filter processing apparatus comprising: a data array restoring unit that restores the data array of the expanded data array subjected to the filter process. The filter processing apparatus according to claim 1,
When the size ratio of the enlarged data array to the original data array is 1.7 or less,
The filter processing execution means executes filter processing on the original enlarged data array. The filter processing apparatus according to claim 1 or 2,
When the original data array and the enlarged data array are two-dimensional arrays,
An array size ratio acquisition means for obtaining a size ratio Rx in the x direction and a size ratio Ry in the y direction of the enlarged data array with respect to the original data array;
An integer ratio acquisition means for obtaining an integer ratio Ix and Iy close to the size ratio Rx in the x direction of the enlarged data array relative to the original data array and the size ratio Ry in the y direction;
The data is rearranged so as to be collected for each of the (Ix-1) jumps in the x direction of the enlarged data array, and then is arranged for each of the data located in the (Iy-1) jumps in the y direction. Data rearrangement means for rearranging data;
Filter processing execution means for executing filter processing on the rearranged enlarged data array;
A filter processing apparatus comprising: a data array restoring unit that restores the data array of the expanded data array subjected to the filter process. The filter processing apparatus according to claim 1 or 2,
When the original data array and the enlarged data array are three-dimensional arrays,
An array size ratio acquisition means for obtaining a size ratio Rx in the x direction of the enlarged data array relative to the original data array, a size ratio Ry in the y direction, and a size ratio Rz in the z direction;
An integer ratio acquisition means for obtaining an integer ratio Ix, Iy, and Iz close to the size ratio Rx in the x direction of the enlarged data array relative to the original data array, the size ratio Ry in the y direction, and the size ratio Rz in the z direction;
The data is rearranged so as to be collected for each of the (Ix-1) jumps in the x direction of the enlarged data array, and then is arranged for each of the data located in the (Iy-1) jumps in the y direction. Data rearranging means for rearranging the data and then rearranging the data so as to be grouped for each of the (Iz-1) jumps in the z direction;
Filter processing execution means for executing filter processing on the rearranged enlarged data array;
A filter processing apparatus comprising: a data array restoring unit that restores the data array of the expanded data array subjected to the filter process.   An MRI apparatus comprising the filter processing apparatus according to claim 1.

Images