CN106204673A - Based on energy spectral filter and the CT image metal artifact bearing calibration of Image Residual re-projection - Google Patents
Based on energy spectral filter and the CT image metal artifact bearing calibration of Image Residual re-projection Download PDFInfo
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Abstract
The present invention relates to a kind of based on energy spectral filter and the CT image metal artifact bearing calibration of Image Residual re-projection, be first calculated filter thickness according to the material attenuation quotient change rate curve that initial ray power spectrum is relevant with energy；And effective high-energy ray transmitance of different materials optical filter is compared by calculating, determine optimum optical filter；Being extracted and deduction by the outer clutter noise of original reconstruction image target area, effectively the scatter artefacts in suppression original image, improves picture contrast.The present invention removes shot noise by residual error re-projection method in original projection, it is independent of collimator or scatter removal after baroque detector, also without priori conditions such as Imaging physics, substantial amounts of shot noise in former projection picture can be removed, be effectively improved the image quality of detected target inside and outside contour.
Description
Technical field
The invention belongs to industry CT technical field of imaging, particularly to one based on energy spectral filter and Image Residual re-projection
CT image metal artifact bearing calibration.
Background technology
Industrial computed tomography (Industrial Computed Tomography, ICT) utilizes different angle
The Transmission Attenuation information of the lower X-ray of degree carries out fault imaging to object, it is possible to noncontact, undamaged in the case of obtain object
Internal structural information.Compared with nondestructiving detecting means conventional with radiography, ultrasound detection, eddy detection technology etc., industry CT
Have that detection speed is fast, space and density resolution advantages of higher, it is possible to show the structure within object to be detected, group intuitively
Become and defective eigenpairs, be widely used in the numerous areas such as Aeronautics and Astronautics, defence and military.In commercial Application, CT examines
Survey object in the majority with metallics.Owing to metallics can make X-ray generation beam hardening and produces a large amount of scattered photon, cause
The characteristics of image not corresponded with physical object structure, referred to as metal artifacts can be produced in CT image, have a strong impact on interior of articles
The identification of effective information, extract and judge.Owing to intravascular stent, metal artificial tooth etc. are in clinical a large amount of uses, metal artifacts is asked
Topic the most generally exists in Medical CT, and imageable target shows as comprising in nonmetallic substance the metallics of finite region.
The impact of medical image is mainly reflected in by metal artifacts observes difficulty to metallics surrounding tissue, brings very to clinical diagnosis
Big puzzlement.Therefore, the research to metal artifacts reduction method is also always study hotspot and the difficult point in CT field.
Current metal artifacts reduction method can be largely classified into three classes: interpolation correction method, iterative corrections method x and mixing school
Execute；Wherein, interpolation correction method is also referred to as sinogram restorative procedure, is that metal artifacts goes a good appetite suddenly appearing in a serious disease most common method, such side
Method, firstly the need of splitting metal at image area and positioning, is then determined in the sinogram that metal is corresponding by orthographic projection and throws
Territory, shadow zone, and the data in this region are regarded as contaminated and rejects, the data in region are rejected in the method reparation of recycling interpolation,
The data after repairing finally are utilized to complete to rebuild；Iterative method is also referred to as the method for successive approximation, and the method needs also exist for determining that metal is just
View field in string figure, and these part data are rejected, then introduce certain priori, by the method for iteration
The projection using missing data is rebuild, and its essence is belonging to missing data and rebuilds；Composed correction method is interpolation method and iteration
The mixing of method, is mainly characterized by interpolation repair process not being once to complete, but is progressively repaiied by the process of continuous iteration
The data of the multiple metallic region rejected, finally complete reconstruction.These methods are required for metallic region first carries out segmentation location, and
The contaminated data navigated to are removed, then passes through or interpolation, or iteration, or the method for interpolation and iterative mixing is to removal
Data carry out reconstruction.Therefore, these algorithms more detect target be applicable to Medical CT is in nonmetallic substance
Comprise the situation of limited regional metal material, then can not be the suitableeest when target is all-metal material for industry CT detects
With.
Summary of the invention
For overcoming deficiency of the prior art, the present invention provides a kind of based on energy spectral filter and the CT of Image Residual re-projection
Image metal artifact bearing calibration, two staples for causing metal artifacts: beam hardening and photon equilibrium state grind
Study carefully, according to estimating power spectrum and filbtercharacteristic, design optimum optical filter, protect to the full extent while filtering low energy ray
Remain for effective X-ray of imaging, it is to avoid collimator after the baroque detector of use, by spuious outside target area
Noise carries out extracting and re-projection, removes substantial amounts of scattered signal in former projection picture, is effectively increased image quality and tested
Survey the contrast of target inside and outside contour.
According to design provided by the present invention, a kind of CT image gold based on energy spectral filter and Image Residual re-projection
Belong to artifact correction method, comprise the steps of:
Step 1, according to attenuation rate change curve and effective rays transmitance, the optimum optical filter of design；
Step 2, shot noise outer to original reconstruction image target area are estimated, by residual error re-projection method former
Begin shot noise is removed in projection, obtain revising projection；
Step 3, project backprojection reconstruction again according to correction, obtain correction of a final proof image.
Above-mentioned, step 1 specifically comprises following content: according to attenuation rate change curve and Beer law formula I=I0e-μl, it is calculated the thickness of optical filter；Pass through formula:It is calculated the effective of different materials optical filter
Radiolucent rate, com-parison and analysis, design optimum optical filter, wherein, L is the thickness of optical filter, I0Represent respectively with I and initially penetrate
Line and through transmitted intensity, μ represents homogeneous substance attenuation quotient, and l represents substance thickness.
Above-mentioned, step 2 specifically comprises following content:
Step 2.1, original projection is carried out backprojection reconstruction, obtain original reconstruction image, to target in original reconstruction image
Profile extracts, and the voxel value outside objective contour in original reconstruction image is set to zero, keeps the voxel in objective contour
It is worth constant, obtains revised target image；
Step 2.2, utilize the original reconstruction revised target image of figure image subtraction, obtain image area residual error；
Step 2.3, image area residual error is carried out low-pass filtering, and carry out scattered signal estimation；
Step 2.4, carry out re-projection according to scattered signal estimated result, scattered signal is transformed into projection from image area
Territory；
Step 2.5, the re-projection result that deduction step 2.4 obtains in original projection, obtain revising projection.
Beneficial effects of the present invention:
1, the present invention is directed to cause two staples of metal artifacts: beam hardening and photon equilibrium state are studied, root
Power spectrum and filbtercharacteristic according to estimates, designs optimum optical filter, retains use while filtering low energy ray to the full extent
Effective X-ray in imaging, it is to avoid collimator after the baroque detector of use, by clutter noise outside target area
Carry out extracting and re-projection, remove substantial amounts of scattered signal in former projection picture, be effectively increased image quality and detected mesh
The contrast of mark inside and outside contour.
2, first the present invention calculates according to the material attenuation quotient change rate curve that initial ray power spectrum is relevant with energy
To filter thickness；And effective high-energy ray transmitance of different materials optical filter is compared by calculating, determine optimum optical filter；
Extracted and deduction by the outer clutter noise of original reconstruction image target area, it is possible to the effectively scattering in suppression original image is pseudo-
Shadow, improves picture contrast；The method for designing of optical filter is applicable to multiple situation, has higher robustness；The present invention is led to
Cross residual error re-projection method in original projection, remove shot noise, be independent of collimator or scattering after baroque detector
Correcting plate, it is not required that the priori conditions such as Imaging physics, it is possible to remove substantial amounts of shot noise in former projection picture, be effectively improved
The image quality of detected target inside and outside contour.
Accompanying drawing illustrates:
Fig. 1 is the schematic flow sheet of the present invention；
Fig. 2 is the flow chart being removed shot noise by residual error re-projection method in original projection of the present invention；
Fig. 3 is the aircraft engine turbo blade schematic diagram in embodiment two used by confirmatory experiment；
Fig. 4 is the effective rays transmitance table that different optical filter is corresponding；
Turbo blade reconstructed results schematic diagram when Fig. 5 is free of light filter；
Turbo blade reconstructed results schematic diagram when Fig. 6 is for using different optical filter；
Fig. 7 calculates chosen area schematic diagram for using copper, lead, three kinds of filter plate reconstructed results signal noise ratio (snr) of image of tungsten；
Fig. 8 is selected trizonal average signal-to-noise ratio in Fig. 7；
Fig. 9 is image area residual sum projection domain residual error schematic diagram in the trimming process using tungsten optical filter；
Figure 10 is the correction of a final proof image schematic diagram using the present invention to obtain.
Detailed description of the invention:
The generation of metal artifacts is the comprehensive embodiment of many factors, substantially can be divided into ray hardened effect, photon equilibrium state
Effect, electronics hunger effect and partial volume effect, wherein beam hardening is principal element.It is all-metal for detection target
The situation of material, when detecting voltage and reaching hundreds of kev, X-ray is taken as the leading factor with Compton scattering with matter interaction, and golden
Belonging to is again strong scattering source, and now, metal artifacts can be regarded as beam hardening effect and photon equilibrium state effect is taken as the leading factor altogether
The result of same-action.
Wherein, the beam hardening origin cause of formation, the molecular ray of the light of identical energy it is referred to as monoenergetic ray.Generally, CT rebuilds
Algorithm, including parsing and the Class of Iterative algorithm of the overwhelming majority, being all based on X-ray is monoenergetic.And in reality, current commercialization
X-ray is all continuous multi-power spectrum.Wherein, the ability that sigmatron penetrates object is strong, and low energy X ray penetrates the ability of object
Relatively weak, after this X-ray allowing for continuous multi-power spectrum passes object, low-energy X-ray is easier to be attenuated, so that
The X-ray energy spectrum that detector receives is compared incident X-rays power spectrum and be there occurs change.This change shows as the X-ray received
Middle high-energy component ratio increases, the most so-called beam hardening phenomenon.
When ray is monoenergetic, from Beer law formula (1), ray meets through ray during homogeneous substance:
I=I0e-μl, (1)
Wherein, I0Representing initial ray respectively with I and through transmitted intensity, μ represents homogeneous substance attenuation quotient, and l represents
Substance thickness.From formula (1), data for projection meets:
That is, projection value and penetration thickness l meets linear relationship.
When ray is multipotency, Beer law formula can be expressed as
I=I0∫S(E)e-∫u(E)dldE, (3)
It can be seen that when u (E) is not constant, during multipotency ray, projection value p and penetration thickness l no longer meets linear closing
System.Therefore, the essential reason that beam hardening artifact produces is: incident X-rays is continuous multi-power spectrum, and same substance is not to
The damping capacity of co-energy X-ray is different.
Separately, the scatter artefacts origin cause of formation, scattering is ray when passing object, and the electron outside nucleus of incident X-rays and material atom is sent out
Raw collision, thus reduce energy and change the process in transmission direction.When there is scattering, detector visits the X-ray that unit receives
Do not only have the most incident photon, and have the photon of scattering.These scattered photons can make spy unit signal deviation actual value, causes
There is scatter artefacts in CT image.Under normal circumstances, scattered photon be random directive from all directions, scattering cross section is more flat
Sliding.When a lot of rays occur scattering, be equivalent in primary signal one layer of low-frequency noise of superposition.Scattered photon is to projection value
Must affect and can be expressed as:
Wherein, IsRepresent scattered photon intensity.
Therefore, scattered ray, as an important noise source in CT imaging process, can make image produce shade, cup-shaped
Artifact and strip artifact etc., cause soft edge, degradation in contrast, seriously reduce picture quality, especially in industry
When metallics being carried out imaging in CT, Scattering Factors proportion shared by metal artifacts significantly increases, it is necessary to scattering
Artifact is suppressed.
The present invention is further detailed explanation with technical scheme below in conjunction with the accompanying drawings, and detailed by preferred embodiment
Describe bright embodiments of the present invention in detail, but embodiments of the present invention are not limited to this.
Embodiment one, shown in Figure 1, a kind of based on energy spectral filter and the CT image metal artifact of Image Residual re-projection
Bearing calibration, comprises the steps of:
Step 1, according to attenuation rate change curve and effective rays transmitance, the optimum optical filter of design；
Step 2, shot noise outer to original reconstruction image target area are estimated, by residual error re-projection method former
Begin shot noise is removed in projection, obtain revising projection；
Step 3, project backprojection reconstruction again according to correction, obtain correction of a final proof image.
The present invention first passes through the optimum optical filter of design, filters the part being prone to hardening in original power spectrum, retains the most simultaneously
Many effective rayses；Then, estimate rebuilding the outer shot noise of image target area, existed by the method for residual error re-projection
Original projection is deducted shot noise；Finally, utilize correction to project backprojection reconstruction again, obtain correction of a final proof image, it is achieved CT
The metal artifacts reduction of image, it is possible to the metal artifacts impact that effectively suppression beam hardening and photon equilibrium state cause, improves image
Contrast and improve image quality.
Embodiment two, sees shown in Fig. 1～10, a kind of based on energy spectral filter and the CT image metal of Image Residual re-projection
Artifact correction method, comprises following content:
Step 1, according to attenuation rate change curve and effective rays transmitance, the optimum optical filter of design, material attenuation rate becomes
Changing curve is the material mass attenuation quotient absolute value to photon energy partial derivative, has reacted material attenuation quotient with photon energy
The severe degree changed and change, when attenuation quotient is changed to zero, represents that material attenuation quotient is not with the change of photon energy
And change, i.e. attenuation quotient has constant value in continuum；And when attenuation quotient rate of change increases, represent that material declines
Subtract the degree increase that coefficient changes with photon energy change, i.e. attenuation quotient diversity under different photon energies increases,
For the attenuation quotient rate of change energy section close to zero, material attenuation quotient approximately equal, now projection value meets as follows:, when S (E) represent normalization energy time spectrum, ∫ S (E) dE=1, therefore, p ≈ ul, i.e. projection value with wear
Length l approximation meets linear relationship thoroughly, meets the algorithm for reconstructing requirement assumed based on monoenergetic, uses the ray of this section of power spectrum to carry out
Can effectively suppress beam hardening artifact during imaging, attenuation quotient change rate curve may determine that and need filter to be prone to hardening
Part, and according to attenuation rate change curve and Beer law formula I=I0e-μl, it is calculated the thickness of optical filter；Effective rays
Transmitance refers to account for the ratio of initial ray through ray in order to imaging after optical filter, optical filter filtering low energy X ray with
Time, also can filter sigmatron；In CT imaging, the size of statistical noise is closely related with the size of effective X-ray intensity,
Increase transmitted intensity and can effectively suppress statistical noise, improve the signal to noise ratio of become image, pass through formula:
It is calculated the effective rays transmitance of different materials optical filter, com-parison and analysis, designs optimum optical filter so that in order to imaging
Transmitted intensity the highest, suppression hardening artifact while, improve image signal to noise ratio, wherein, L is the thickness of optical filter, I0And I
Representing initial ray respectively and through transmitted intensity, μ represents homogeneous substance attenuation quotient.
Step 2, shot noise outer to original reconstruction image target area are estimated, by residual error re-projection method former
Begin projection in remove shot noise, obtain revise projection, based on be scattering into as in two physics facts, 1) original reconstruction image
Nonzero value outside middle objective contour should be artifact, the shot noise that this part artifact is mainly derived from original projection；2) dissipate
Penetrating signal is a kind of low frequency signal, removes shot noise by residual error re-projection method and specifically comprise as follows in original projection:
Step 2.1, original projection is carried out backprojection reconstruction, obtain original reconstruction image, to target in original reconstruction image
Profile extracts, and the voxel value outside objective contour in original reconstruction image is set to zero, keeps the voxel in objective contour
It is worth constant, obtains revised target image, the image procossing mode of routine can be used to carry out the extraction of objective contour, such as,
Use image partition method based on threshold value；
Step 2.2, utilize the original reconstruction revised target image of figure image subtraction, obtain image area residual error；
Step 2.3, image area residual error is carried out low-pass filtering, and carry out scattered signal estimation；
Step 2.4, carry out re-projection according to scattered signal estimated result, scattered signal is transformed into projection from image area
Territory；
Step 2.5, the re-projection result that deduction step 2.4 obtains in original projection, obtain revising projection.
Step 3, project backprojection reconstruction again according to correction, obtain correction of a final proof image.
The present invention is independent of collimator or scatter removal after baroque detector, it is not required that Imaging physics etc. are first
Test condition, it is possible to remove substantial amounts of shot noise in former projection picture, be effectively improved the one-tenth picture element of detected target inside and outside contour
Amount.
Below by specific experiment, the present invention will be further described:
Using actual industrial CT system that engine turbine blade is carried out imaging, in actual industrial CT system, radiographic source is
U.S. Varian HPX-450-11, detector is Germany PerkinElmer-XRD-1621, aircraft engine turbo blade, as
Shown in Fig. 3, and the picture quality before and after correction is contrasted, respectively without filter plate and use aluminum, copper, lead and the filter of four kinds of tungsten
In the case of wave plate, engine turbine blade image acquisition and reconstruction are carried out.By calculating, different optical filters the most munificent
Degree is respectively 150mm, 16mm, 1mm and 0.8mm, and corresponding effective rays transmitance as shown in Figure 4, relatively can by the numeric ratio of Fig. 4
To find out, be tungsten, lead, copper, aluminum the most successively to X-ray retention characteristic effective in initial power spectrum, i.e. having for imaging
Effect X-ray intensity is tungsten, lead, copper, aluminum the most successively.Therefore, based on above effective X-ray intensity and imaging signal to noise ratio
Analyzing, in four kinds of materials, tungsten is the optical filter that override selects, and it can hold up to while filtering low energy X ray
Better image signal to noise ratio can be kept while effectively sigmatron, i.e. correction hardening artifact.
Experiment condition is tube voltage 300kv, and projection acquisition is spaced apart 1 degree, acquired projections number 360 width, and image reconstruction uses
FDK algorithm, without reconstructed results during filter plate as it is shown in figure 5, use the reconstructed results of four kinds of optical filters the most as shown in Figure 6, Fig. 6
In: (a) represents that using the reconstructed results of aluminum filter plate, (b) to represent uses the reconstructed results of copper filter plate, (c) expression to use lead
The reconstructed results of filter plate, (d) represent the reconstructed results using tungsten filter plate, as seen from the figure, and original when not using optical filter
Rebuilding in image and contain substantial amounts of metal artifacts, picture contrast is poor, and edge is the fuzzyyest, especially blade concave edges
The most serious by the image of artifact.After using optical filter as seen from Figure 6, in original image, hardening artifact has obtained very great Cheng
The removal of degree, comparison is strengthened by blade edge, and the concave edges the most serious by artifact effects still becomes apparent from, but
It is that the correction result using aluminum optical filter is good apparently without other optical filter, and this is primarily due to aluminum and is filtering low energy X ray
Filter substantial amounts of sigmatron simultaneously, caused the effective X-ray in order to imaging to greatly reduce, so intuitively going to see image
Noise is maximum, and this is consistent with analysis herein above；And the calibration result of copper, lead and tungsten is more preferable, this is primarily due to these three
Optical filter can retain more sigmatron when filtering low energy X ray.Observation directly perceived, compares lead and tungsten optical filter, uses
In the result of copper optical filter, noise becomes apparent from.For comparing checking copper, lead, the action effect of three kinds of filter plates of tungsten further, logical
Cross the signal noise ratio (snr) of image comparing three kinds of filter plate reconstructed results, signal-to-noise ratio computation region choose as it is shown in fig. 7, trizonal
As shown in Figure 8, the signal noise ratio (snr) of image obtained when using copper filter plate is 5.14 to average signal-to-noise ratio, uses lead filter plate to obtain
Signal noise ratio (snr) of image is 6.56, and the signal noise ratio (snr) of image using tungsten filter plate to obtain is 6.64, illustrates in above 4 in material, tungsten
Effect is best.
Through hardening artifact correct, original reconstructed image quality is obviously improved, blade edge obtained recover and
Contrast promotes, but, affected by scatter artefacts, had substantial amounts of clutter noise outside image target area so that edge contrast
Spend the most not ideal enough.Therefore, correction result based on tungsten optical filter, use further and herein scatter artefacts is corrected,
Wherein, the image area residual sum projection domain residual error in trimming process is distinguished as it is shown in figure 9, (a) represents image area residual error in Fig. 9,
B () represents projection domain residual error, (a) in Fig. 9 can be seen that, contains substantial amounts of noise signal in original image, uses this paper side
These noises are extracted and are transformed in the result such as Fig. 9 of projection domain shown in (b) by method, and final correction result images is by Figure 10 institute
Show, be efficiently removed by substantial amounts of clutter noise in the result deducting after noise signal in original projection and again rebuild,
Picture quality has clear improvement, and picture contrast improves further, and blade outer edge becomes apparent from.
The present invention is directed to cause two staples of metal artifacts: beam hardening and photon equilibrium state are studied, according to
Estimate power spectrum and filbtercharacteristic, design optimum optical filter, be preserved for the full extent while filtering low energy ray
Effective X-ray of imaging, it is to avoid collimator after the baroque detector of use, by entering clutter noise outside target area
Row extracts and re-projection, removes substantial amounts of scattered signal in former projection picture, is effectively increased image quality and detected target
The contrast of inside and outside contour.
The invention is not limited in above-mentioned detailed description of the invention, those skilled in the art also can make multiple change accordingly,
But any with the present invention equivalent or similar change all should contain within the scope of the claims.
Claims (3)
1. one kind based on can spectral filter and the CT image metal artifact bearing calibration of Image Residual re-projection, it is characterised in that: bag
Containing following steps:
Step 1, according to attenuation rate change curve and effective rays transmitance, the optimum optical filter of design；
Step 2, shot noise outer to original reconstruction image target area are estimated, by residual error re-projection method in original throwing
Shadow is removed shot noise, obtains revising projection；
Step 3, project backprojection reconstruction again according to correction, obtain correction of a final proof image.
The most according to claim 1 based on energy spectral filter and the CT image metal artifact correction side of Image Residual re-projection
Method, it is characterised in that: described step 1 specifically comprises following content: according to attenuation rate change curve and Beer law formula I=
I0e-μl, it is calculated the thickness of optical filter；Pass through formula:It is calculated having of different materials optical filter
Effect Radiolucent rate, com-parison and analysis, design optimum optical filter, wherein, L is the thickness of optical filter, I0Represent initial respectively with I
Ray and through transmitted intensity, μ represents homogeneous substance attenuation quotient, and l represents substance thickness.
The most according to claim 1 based on energy spectral filter and the CT image metal artifact correction side of Image Residual re-projection
Method, it is characterised in that: described step 2 specifically comprises following content:
Step 2.1, original projection is carried out backprojection reconstruction, obtain original reconstruction image, to objective contour in original reconstruction image
Extract, the voxel value outside objective contour in original reconstruction image is set to zero, keep the voxel value in objective contour not
Become, obtain revised target image；
Step 2.2, utilize the original reconstruction revised target image of figure image subtraction, obtain image area residual error；
Step 2.3, image area residual error is carried out low-pass filtering, and carry out scattered signal estimation；
Step 2.4, carry out re-projection according to scattered signal estimated result, scattered signal is transformed into projection domain from image area；
Step 2.5, the re-projection result that deduction step 2.4 obtains in original projection, obtain revising projection.
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Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106955118A (en) * | 2017-04-11 | 2017-07-18 | 沈阳开普医疗影像技术有限公司 | The single of CT shape filter defects can antidote |
| CN109540930A (en) * | 2018-09-17 | 2019-03-29 | 南京航空航天大学 | A kind of multi-power spectrum x-ray imaging scattering estimation and bearing calibration |
| CN110458762A (en) * | 2019-07-02 | 2019-11-15 | 山东科技大学 | A kind of CT image beam hardening artifact correction system based on adjustable double factor |
| CN111096761A (en) * | 2018-10-29 | 2020-05-05 | 上海西门子医疗器械有限公司 | Method, device and related equipment for correcting wedge filter scattering |
| CN111476856A (en) * | 2020-04-08 | 2020-07-31 | 中北大学 | Multispectral CT imaging method |
| CN112508808A (en) * | 2020-11-26 | 2021-03-16 | 中国人民解放军战略支援部队信息工程大学 | CT (computed tomography) dual-domain joint metal artifact correction method based on generation countermeasure network |
| CN113177991A (en) * | 2021-04-29 | 2021-07-27 | 中国科学技术大学 | Method for correcting scattering artifacts in CBCT (cone beam computed tomography) based on planned CT (computed tomography) |
| CN114399564A (en) * | 2022-03-25 | 2022-04-26 | 康达洲际医疗器械有限公司 | Cone beam computed tomography imaging method and system based on scattering identification |
| CN114758066A (en) * | 2022-03-30 | 2022-07-15 | 清华大学 | Image processing method, apparatus, device, storage medium, and computer program product |
| CN114781096A (en) * | 2022-05-10 | 2022-07-22 | 西华大学 | Blade design and object comparison method based on 2MeV accelerator CT imaging system |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103559699A (en) * | 2013-11-18 | 2014-02-05 | 首都师范大学 | Multi-energy-spectrum CT image reconstruction method based on projection estimation |
| CN103700124A (en) * | 2013-12-27 | 2014-04-02 | 公安部第一研究所 | Method for metal effect inhibition of X-ray dual-energy CT (computer tomography) imaging |
| US20160113617A1 (en) * | 2013-06-19 | 2016-04-28 | Koninklijke Philips N.V. | Calibration of imagers with dynamic beam shapers |
-
2016
- 2016-06-29 CN CN201610509259.8A patent/CN106204673B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20160113617A1 (en) * | 2013-06-19 | 2016-04-28 | Koninklijke Philips N.V. | Calibration of imagers with dynamic beam shapers |
| CN103559699A (en) * | 2013-11-18 | 2014-02-05 | 首都师范大学 | Multi-energy-spectrum CT image reconstruction method based on projection estimation |
| CN103700124A (en) * | 2013-12-27 | 2014-04-02 | 公安部第一研究所 | Method for metal effect inhibition of X-ray dual-energy CT (computer tomography) imaging |
Non-Patent Citations (3)
| Title |
|---|
| CATHERINE LEMMENS ET AL.: "Suppression of Metal Artifacts in CT Using a Reconstruction Procedure That Combines MAP and Projection Completion", 《 IEEE TRANSACTIONS ON MEDICAL IMAGING》 * |
| 韩玉 等: "一种基于Radon逆变换的半覆盖螺旋锥束CT重建算法", 《物理学报》 * |
| 魏星 等: "多金属物体CT图像的金属伪影校正", 《物理学报》 * |
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