CN105572713A - Multichannel film radiation amount measurement method - Google Patents

Multichannel film radiation amount measurement method Download PDF

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Publication number
CN105572713A
CN105572713A CN201510947419.2A CN201510947419A CN105572713A CN 105572713 A CN105572713 A CN 105572713A CN 201510947419 A CN201510947419 A CN 201510947419A CN 105572713 A CN105572713 A CN 105572713A
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exit dose
measuring method
passage
pixel
film
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CN105572713B (en
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黄佑钟
顾群
袁志刚
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Shanghai United Imaging Healthcare Co Ltd
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Shanghai United Imaging Healthcare Co Ltd
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01T—MEASUREMENT OF NUCLEAR OR X-RADIATION
    • G01T1/00—Measuring X-radiation, gamma radiation, corpuscular radiation, or cosmic radiation
    • G01T1/16—Measuring radiation intensity
    • G01T1/167—Measuring radioactive content of objects, e.g. contamination

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  • Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
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  • High Energy & Nuclear Physics (AREA)
  • Molecular Biology (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Measurement Of Radiation (AREA)

Abstract

The invention provides a multichannel film radiation amount measurement method. By use of radiation amounts based on different-color channels, an optimization model with top and bottom limitation constraint conditions is established, a radiation amount corresponding to each pixel point after a film is scanned is calculated and rectified, and based on the optimization model provided by the invention, the radiation amounts of the multiple channels are converted into solution of m*n one-dimensional nonlinear optimization problems with the top and bottom limitation constraint conditions. Compared to an optimization model in the prior art, the optimization model established in the method simplifies the optimization model in the prior art, reduces the calculation difficulty and shortens the calculation time for solving the radiation amounts; and measurement is carried out by use of the radiation amounts of the different-color channels for the film, interference caused by a measurement environment to a measurement result is reduced, real values of the radiation amounts are quite accurately represented, and the measurement precision of multi-channel measurement of the radiation amounts of the film is guaranteed while the calculation speed is improved.

Description

Multichannel film exit dose measuring method
Technical field
The present invention relates to field of medical technology, particularly one multichannel film exit dose measuring method.
Background technology
Film dosimetry is a kind of conventional exit dose measuring method, and ultimate principle is that film changes color (becoming blue with the impact of dose radiation) under high energy radiation line exposing, and exit dose adds conference makes color burn.Following nonlinear relationship is met between the color depth of usual film and exit dose:
d X = - l o g ( a X + b X D X c X + D X ) (formula 1);
Be equivalent to D X = a X 10 d X - c X 1 - b X 10 d X (formula 2);
Wherein, d xrepresent color depth value, D xrepresent corresponding exit dose, a x, b x, c xrepresent fitting parameter, under different measuring conditions, a x, b x, c xto change to some extent, a x, b x, c xthe data of calibration point that can record by experiment obtains through least square fitting according to formula 2, and data of calibration point is here many group color depth value d xwith the exit dose D of correspondence x.
Concrete, existing film dosimetry method is applicable to the measurement of the exit dose of the film of individual color channel, and what single channel was often referred to generation here is red channel, is first obtained the color depth value d of each pixel by the scanned picture of scanner acquisition film x, then by the red channel color depth value d of picture xsubstitute into after formula 2 calculates and can obtain exit dose D corresponding to each pixel in picture x, and then obtain the exit dose matrix of whole picture, the exit dose of the pixel of the corresponding respective scanned position of each element in exit dose matrix.
But, the in fact color depth value d of film xeasily be subject to the interference of the many factors such as measurement environment around, such as film stock thickness is uneven, scanner exists noise etc.In the Film processing of routine, owing to only used individual color channel, be therefore easy to the impact be interfered, cause exit dose measuring accuracy lower.
For the problems referred to above, a kind of multichannel film measuring method is suggested.In theory, film is after the color depth Value Data that scanner scanning obtains multiple Color Channel, adopt the color depth value of any one Color Channel should be the same through the exit dose matrix value that formula 2 calculates, but actual result but not so, please refer to Fig. 1, it is the exit dose result figure using the color depth value of different color channels to calculate.As shown in Figure 1, due to the outwardness of test environment interference, make the radiation value of each path computation different from each other.
For this problem, prior art proposes to set up Optimized model based on the exit dose matrix of different passage, obtains optimum rectification parameter matrix, to reduce the interference that measurement environment is brought by solving this Optimized model.But because this Optimized model is a Large-scale Optimization Problems, there will be and solve mistake consuming time for a long time and even solve the problem of failure.Therefore, need to seek one exit dose measuring method fast and accurately.
Summary of the invention
The object of the present invention is to provide a kind of multichannel film exit dose measuring method, not high and solve the problem of overlong time with the measurement result precision solving multichannel film exit dose measuring method in prior art.
For solving the problems of the technologies described above, the invention provides a kind of multichannel film exit dose measuring method, described multichannel film exit dose measuring method comprises:
Scan film obtains the color depth value of m × n pixel in different color channels, wherein, m >=0, n >=0, to each pixel, set up the Optimized model being with bound constraint condition based on the relation between color depth value and exit dose, utilize the exit dose of each pixel of described seismic responses calculated.
Optionally, in described multichannel film exit dose measuring method, described Optimized model is built by following formula:
F ( Δ d ) = min Δ d max X i , X j ∈ { X 1 ... X N } | D X i ( Δ d ) - D X j ( Δ d ) | ;
Wherein, bound constraint condition is 1-δ≤Δ d≤1+ δ; Δ d represents decision variable; δ represents the adjusting range threshold value of Δ d; X represents Color Channel, { X 1... X nrepresent the set of all colours passage, X i, X jrepresent any two Color Channels wherein; a x, b x, c xrepresent the fitting parameter of X passage; F (Δ d) represents the objective function of Optimized model; D x(Δ d) represents the exit dose on X passage, is the function about Δ d; d xrepresent the color depth value by scanning on the X passage that obtains; d xΔ d represents the color depth value of the X passage after rectification.
Optionally, in described multichannel film exit dose measuring method, one-dimensional linear searching algorithm is adopted to obtain the optimum solution of decision variable.
Optionally, in described multichannel film exit dose measuring method, golden section search algorithm is adopted to obtain the optimum solution of decision variable.
Optionally, in described multichannel film exit dose measuring method, before the exit dose utilizing each pixel of seismic responses calculated built, also comprise the step of Exception Filter pixel.
Optionally, in described multichannel film exit dose measuring method, described extraordinary image vegetarian refreshments is that radiation value is less than zero or be greater than the pixel of maximum set threshold value.
Optionally, in described multichannel film exit dose measuring method, the fitting parameter a of described X passage x, b x, c xby organizing color depth value and corresponding exit dose, according to formula more obtain through least square fitting, wherein, d xrepresent the color depth value of X passage, D xrepresent the exit dose of X passage.
Optionally, in described multichannel film exit dose measuring method, described hyperchannel comprises green channel, red channel and blue channel.
Optionally, in described multichannel film exit dose measuring method, the color depth value in different color channels is obtained by scanner scanning.
In multichannel film exit dose measuring method provided by the present invention, the exit dose based on different color channels is utilized to set up the Optimized model of band bound constraint condition, calculate and the exit dose that each pixel is corresponding after correcting scan film, will multichannel film exit dose be calculated be converted into the nonlinear optimal problem of the band bound constraint condition solving m × n one dimension based on Optimized model of the present invention.Compared to Optimized model of the prior art, the Optimized model that the present invention sets up, simplifies Optimized model of the prior art, reduces difficulty in computation, shortens the computing time solving exit dose;
Further, the optimum solution of the above-mentioned one dimension Optimized model of one-dimensional linear searching algorithm rapid solving can be adopted, be reduced in the time spent in solution procedure further;
Further, before utilizing seismic responses calculated exit dose of the present invention, extraordinary image vegetarian refreshments is filtered, shortens computing time;
The present invention utilizes the exit dose of different color channels to film to measure, decrease the interference that measurement environment causes measurement result, characterize the actual value of exit dose comparatively accurately, while improving computing velocity, ensure the measuring accuracy of multi-channel measurement film exit dose.
Accompanying drawing explanation
Fig. 1 is the exit dose result figure for using the color value of different color channels to calculate;
Fig. 2 is the exit dose result figure adopting the multichannel film exit dose measuring method in the embodiment of the present invention to calculate.
Embodiment
Below in conjunction with the drawings and specific embodiments, the multichannel film exit dose measuring method that the present invention proposes is described in further detail.According to the following describes and claims, advantages and features of the invention will be clearer.It should be noted that, accompanying drawing all adopts the form that simplifies very much and all uses non-ratio accurately, only in order to object that is convenient, the aid illustration embodiment of the present invention lucidly.
The invention provides a kind of multichannel film exit dose measuring method, scan film obtains the color depth value of m × n pixel in different color channels, wherein, m >=0, n >=0, to each pixel, set up the Optimized model being with bound constraint condition based on the relation between color depth value and exit dose, utilize the exit dose of each pixel of described seismic responses calculated.
Wherein, described Optimized model is by formula 3, and formula 4 and formula 5 build:
F ( Δ d ) = min Δ d max X i , X j ∈ { X 1 ... X N } | D X i ( Δ d ) - D X j ( Δ d ) | (formula 3);
D X ( Δ d ) = a X 10 d X Δ d - c X 1 - b X 10 d X Δ d (formula 4);
1-δ≤Δ d≤1+ δ (formula 5);
Wherein, Δ d represents decision variable; δ represents the adjusting range threshold value of Δ d; X represents Color Channel, { X 1... X nrepresent the set of all colours passage, X i, X jrepresent any two Color Channels wherein; a x, b x, c xrepresent the fitting parameter of X passage; F (Δ d) represents the objective function of Optimized model; D x(Δ d) represents the exit dose on X passage, is the function about Δ d; d xrepresent the color depth value by scanning on the X passage that obtains; d xΔ d represents the color depth value of the X passage after rectification.Preferably, in the present embodiment, δ gets 0.2.
Wherein, the fitting parameter possibility difference that different color channels is corresponding, obtains respectively by the data of calibration point matching under respective channel, the fitting parameter a of such as X passage x, b x, c x, the many groups color depth value d under the data of calibration point recorded by experiment and X passage xwith the exit dose D of correspondence x, according to formula obtain through least square fitting.
For in formula 3 about D xthe numerical value of (Δ d) adopts the content to replace of formula 4, and the unknown parameter now existed in formula 3 is Δ d, and formula 5 is the bound constraint condition of Optimized model, the d in formula 3 xcan be obtained by scanner scanning, be measured value, due to the impact of the disturbing factors such as measurement environment, and measured value d xnumerical value be the color depth value of X passage actual value and interference coefficient result.For this problem, when building Optimized model, introduce this decision variable of Δ d to d xrevise, use d xΔ d characterizes the color depth value of the X passage after correcting, and decreases the interference disturbed and cause measurement result, improves the precision of measurement result.
In order to understand the reliability of measuring method of the present invention preferably, please refer to Fig. 1 and Fig. 2, Fig. 2 is the result figure adopting the measuring method of multichannel film exit dose of the present invention to measure the measurement of multichannel film exit dose.The result of comparison diagram 1 and Fig. 2 is known, and the Color Channel of three shown in Fig. 1 is all different for the measurement result of the radiation value of same pixel, is not inconsistent with notional result, and this is that in actual measurement, the interference of environmental factor causes; And in Fig. 2 three colors passage in the radiation value of same pixel clearly more consistent, conform to notional result, illustrate that method of the present invention can reduce the impact of interference on measurement result of environmental factor, improve the precision measuring structure.
Preferably, when solving the optimum solution of Δ d, with Δ d=1 for initial point adopts one-dimensional linear searching algorithm to solve above-mentioned Optimized model, thus find suitable Δ d that the maximal value of the exit dose deviation between each Color Channel is minimized.Preferably, golden section search algorithm is selected.Golden section search algorithm is a kind of known range be worth most by constantly reducing unimodal function, thus finds the method be worth most, and therefore it can converge to the optimum solution of Δ d in limited step, greatly improves the speed calculating and solve.
Further, before the exit dose utilizing each pixel of seismic responses calculated built, the step of Exception Filter pixel is also comprised.In the present embodiment, radiate the pixel that the minus pixel of value or radiation value be greater than maximum set threshold value and be namely identified as extraordinary image vegetarian refreshments.The radiation value of extraordinary image vegetarian refreshments passes through formula calculate, wherein a x, b x, c xfor the fitting parameter obtained by above-mentioned data of calibration point matching, d xfor color depth value, D xfor exit dose to be calculated.
In the present embodiment, scan film obtains the color depth value d of each pixel on each passage x, through above-mentioned formula calculate the radiation value D of corresponding each passage x, for any one pixel, as long as the radiation value D of any one passage xbe less than zero or be greater than maximum set threshold value, then think that this pixel is extraordinary image vegetarian refreshments, the radiation value of this pixel without the need to using described seismic responses calculated, and directly uses formula 2 to calculate.
Such as, scan film obtains the color depth value of each pixel on green channel, red channel and blue channel, through formula calculate the radiation value of corresponding each passage, to one of them pixel, if the radiation value of this pixel on green channel is greater than maximum set threshold value, then think that this pixel is extraordinary image vegetarian refreshments, the radiation value on the various channels of this pixel directly adopts formula 2 to calculate.
Those skilled in the art can set maximum set threshold value according to actual conditions, such as, be set as the twice of maximum exit dose in above-mentioned data of calibration point.
Owing to first extraordinary image vegetarian refreshments being filtered out, therefore only need to calculate the pixel in film except extraordinary image vegetarian refreshments, thus decrease calculated amount, shorten the time needed for computation and measurement result.
To sum up, in multichannel film exit dose measuring method provided by the present invention, the exit dose based on different color channels is utilized to set up the Optimized model of band bound constraint condition, calculate and the exit dose that each pixel is corresponding after correcting scan film, will multichannel film exit dose be calculated be converted into the nonlinear optimal problem of the band bound constraint condition solving m × n one dimension based on Optimized model of the present invention.Compared to Optimized model of the prior art, the Optimized model that the present invention sets up, simplifies Optimized model of the prior art, reduces difficulty in computation, shortens the computing time solving exit dose;
Further, the optimum solution of the above-mentioned one dimension Optimized model of one-dimensional linear searching algorithm rapid solving can be adopted, be reduced in the time spent by solution procedure further;
Further, before utilizing seismic responses calculated exit dose of the present invention, extraordinary image vegetarian refreshments is filtered, shortens computing time;
The present invention utilizes the exit dose of different color channels to film to measure, decrease the interference that measurement environment causes measurement result, characterize the actual value of exit dose comparatively accurately, while improving computing velocity, ensure the measuring accuracy of multi-channel measurement film exit dose.
Foregoing description is only the description to present pre-ferred embodiments, any restriction not to the scope of the invention, and any change that the those of ordinary skill in field of the present invention does according to above-mentioned disclosure, modification, all belong to the protection domain of claims.

Claims (9)

1. a multichannel film exit dose measuring method, comprise: scan film obtains the color depth value of m × n pixel in different color channels, wherein, m >=0, n >=0, to each pixel, set up the Optimized model being with bound constraint condition based on the relation between color depth value and exit dose, utilize the exit dose of each pixel of described seismic responses calculated.
2. multichannel film exit dose measuring method as claimed in claim 1, it is characterized in that, described Optimized model is built by following formula:
F ( Δ d ) = m i n Δ d m a x X i , X j ∈ { X 1 ... X N } | D X i ( Δ d ) - D X j ( Δ d ) | ;
Wherein, bound constraint condition is 1-δ≤Δ d≤1+ δ; Δ d represents decision variable; δ represents the adjusting range threshold value of Δ d; X represents Color Channel, { X 1x nrepresent the set of all colours passage, X i, X jrepresent any two Color Channels wherein; a x, b x, c xrepresent the fitting parameter of X passage; F (Δ d) represents the objective function of Optimized model; D x(Δ d) represents the exit dose on X passage, is the function about Δ d; d xrepresent the color depth value by scanning on the X passage that obtains; d xΔ d represents the color depth value of the X passage after rectification.
3. multichannel film exit dose measuring method as claimed in claim 2, is characterized in that, adopts one-dimensional linear searching algorithm to obtain the optimum solution of decision variable.
4. multichannel film exit dose measuring method as claimed in claim 3, is characterized in that, adopts golden section search algorithm to obtain the optimum solution of decision variable.
5. multichannel film exit dose measuring method as claimed in claim 1, is characterized in that, before the exit dose utilizing each pixel of seismic responses calculated built, also comprises the step of Exception Filter pixel.
6. multichannel film exit dose measuring method as claimed in claim 5, is characterized in that, described extraordinary image vegetarian refreshments is that radiation value is less than zero or be greater than the pixel of maximum set threshold value.
7. multichannel film exit dose measuring method as claimed in claim 2, is characterized in that, the fitting parameter a of described X passage x, b x, c xby organizing color depth value and corresponding exit dose, according to formula more obtain through least square fitting, wherein, d xrepresent the color depth value of X passage, D xrepresent the exit dose of X passage.
8. the multichannel film exit dose measuring method according to any one of claim 1 ~ 6, it is characterized in that, described hyperchannel comprises green channel, red channel and blue channel.
9. the multichannel film exit dose measuring method according to any one of claim 1 ~ 6, it is characterized in that, the color depth value in different color channels is obtained by scanner scanning.
CN201510947419.2A 2015-12-16 2015-12-16 The film of multichannel radiates measuring method Active CN105572713B (en)

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Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103097912A (en) * 2010-04-09 2013-05-08 Isp投资公司 Radiation dosimetry method
WO2013138088A2 (en) * 2012-03-15 2013-09-19 Isp Investments, Inc. Efficient method for radiochromic film dosimetry

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103097912A (en) * 2010-04-09 2013-05-08 Isp投资公司 Radiation dosimetry method
WO2013138088A2 (en) * 2012-03-15 2013-09-19 Isp Investments, Inc. Efficient method for radiochromic film dosimetry
CN104662443A (en) * 2012-03-15 2015-05-27 Isp投资公司 Efficient method for radiochromic film dosimetry

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
施常备 等: "辐射剂量的胶片测量", 《现代肿瘤医学》 *
涂彧: "普通X射线诊断设备的质量控制", 《国外医学》 *

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Address after: 201807 Shanghai City, north of the city of Jiading District Road No. 2258

Patentee after: Shanghai Lianying Medical Technology Co., Ltd

Address before: 201807 Shanghai City, north of the city of Jiading District Road No. 2258

Patentee before: SHANGHAI UNITED IMAGING HEALTHCARE Co.,Ltd.