CN115830170B - Phase information-based method and system for removing image artifact of sweep frequency endoscopic OCT (optical coherence tomography) - Google Patents
Phase information-based method and system for removing image artifact of sweep frequency endoscopic OCT (optical coherence tomography) Download PDFInfo
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Abstract
The invention discloses a method and a system for removing an image artifact of a sweep frequency endoscopic OCT (optical coherence tomography) based on phase information, wherein the method comprises the following steps: acquiring background information data before connecting a catheter and original data of sweep OCT; processing the original data and then carrying out phase analysis; obtaining a phase shift array according to the data after the phase analysis; the phase shift array is brought into the original data, and the original data is calibrated by the phase shift array to obtain calibrated phase synchronous data; and performing difference operation by using the background information data and the calibrated phase synchronization data to obtain artifact-removed data. The invention also discloses a frequency scanning endoscopic OCT image artifact removal system based on the phase information, which is used for implementing the method, is suitable for frequency scanning endoscopic OCT of a plurality of models of single channel and double channels, has a simple structure and good imaging effect, and solves the problem that when the traditional OCT is directly carried out to remove the artifact, the phase is asynchronous and the artifact cannot be completely removed.
Description
Technical Field
The invention relates to the technical field of OCT imaging, in particular to a method and a system for removing imaging artifacts of sweep frequency endoscopic OCT based on phase information.
Background
Worldwide, cardiovascular and cerebrovascular diseases have become one of the major diseases threatening human health, and coronary atherosclerosis is the major cause of cardiovascular and cerebrovascular diseases. Optical coherence tomography (optical coherence tomography, OCT) has the characteristics of high resolution, large signal to noise ratio and the like, is a technique for performing tomography on an object by measuring the intensity of backward scattered light of the object, can probe a biological tissue micron-sized structure, and is a high-resolution imaging technique. Is an important imaging technology for diagnosing cardiovascular and cerebrovascular diseases.
OCT is based on optical principle imaging, one of the two paths of optical signals enters the reference arm, and the other path enters the sample arm. A low coherence signal is generated by two return light paths. Both the reference arm and the sample arm exist a combination of multiple devices, such as fiber flange connections or fusion splices. By switching or soldering these devices, gaps, bubbles or other abnormal reflections are not avoided due to process tolerances or other reasons, which can lead to signal disturbances and thus to image artifacts. Because of the special property of the sweep frequency light source, the phase information of the sweep frequency light source is inconsistent with that of the broadband light source, and the jitter phenomenon exists in the phase of the sweep frequency light source. When the artifact is removed, the effect of removing the artifact can not be achieved only by a background reduction mode. In the field of endoscopic OCT, the system design based on a sweep frequency scheme can inhibit common mode signals and amplify differential mode signals through a balance detector, but the artifact phenomenon caused by signal interference cannot be effectively inhibited.
Related researches are also carried out on the control of the phase precision of the scanning light source at home and abroad, and the method is mainly divided into two types, namely, adding MZI cascade (CN 201310020839.7-Ding Zhihua and the like) through system design, adding an additional calibration mirror device (Harvard medical college B.J and the like) on an interference arm, such as FDML mode locking technology (FUJI and the like) and gas reference phase sensitive scanning OCT method (Texas R.V and the like), and carrying out iterative calculation through digital information.
The first approach based on system improvement is high in complexity, resulting in relatively large design stability and production challenges. Another iterative method through digital information is based on a galvanometer mode, which is not applicable to an endoscopic scanning mode. Both of these schools are based on phase-purpose calibration depth and resolution information improvement, and do not involve phase-information-based artifact removal issues.
The invention provides a design method for artifact analysis and removal, which aims at different technical routes and different implementation methods, and can effectively remove artifacts through phase information analysis.
Disclosure of Invention
Therefore, the invention aims to provide a frequency sweep endoscopic OCT image artifact removal method and system based on phase information, which solve the problem that artifact residues cannot be completely removed when artifacts are removed by the traditional method.
In order to achieve the above purpose, the method for removing the image artifact of the sweep frequency endoscopic OCT based on the phase information comprises the following steps:
s1, acquiring background information data before catheter connection and original data of sweep OCT;
s2, processing the original data and then carrying out phase analysis; obtaining a phase shift array according to the data after the phase analysis;
s3, bringing the phase shift array into the original data, and calibrating the original data by using the phase shift array to obtain calibrated phase synchronous data;
and S4, performing difference operation by using the background information data and the calibrated phase synchronization data to obtain artifact-removed data.
Further preferably, in S1, the obtaining of the original data of the swept OCT includes single-channel endoscopic OCT data;
optionally, the raw data for acquiring swept OCT includes dual channel endoscopic OCT data and k-clock data.
Further preferably, when the acquired original data of the swept OCT is single-channel endoscopic OCT data, in S2, further comprising:
s210, after carrying out frequency domain transformation on the original data, obtaining artifact spike information;
s220, performing phase analysis on the acquired artifact spike information.
Further preferably, in S2, when obtaining a phase shift array according to the data after phase analysis, a phase comparison method is adopted to obtain the phase shift array;
the phase comparison method comprises the steps of selecting any one of the A-line lines as a datum line and calculating phase offset information for other A-line lines.
Optionally, in S2, when obtaining a phase offset array according to the data after phase analysis, a traversal comparison method is adopted to obtain the phase offset array;
the traversal comparison method comprises the steps of selecting any one of the A-line lines as a datum line, performing positive or negative offset on other A-line lines in original data, performing phase comparison with the datum line, performing traversal within a preset threshold range, and recording offset values; and integrating the offset value of each A-line with the corresponding offset direction to form a phase offset array.
Further preferably, in S210, after performing frequency domain transformation on the original data, artifact spike information is obtained, which includes the following steps:
s211, performing frequency domain transformation on a plurality of A-line data contained in one frame of data in the original data;
s212, setting a threshold function according to the transformed frequency domain information by adopting the following formula, and capturing an artifact peak;
L=S(PowerPeak)/N(Bg)；
wherein PowerPeak is a grabbing peak, bg is a background, S (PowerPeak) is a main peak intensity, and N (Bg) is a background intensity;
s213, searching an artifact peak according to the index direction and a preset search range by taking the point coordinate of each A-line as a starting point according to the set threshold function, and acquiring the peak position.
Further preferably, in S220, the phase analysis is performed on the obtained artifact spike information, including the following steps:
s221, constructing a filter according to peak position and amplitude information in the acquired peak artifact information;
s222, filtering peak values within a set bandwidth by using the constructed filter;
s223, performing inverse phase analysis on the filtered spike information after inverse Fourier transform.
Optionally, when the original data of the obtained swept OCT is dual-channel endoscopic OCT data and k-clock data, in S2, the phase information is obtained by hilbert transform for the obtained k-clock data;
combining the dual-channel endoscopic OCT data with the phase information to form a complex signal with the phase information;
and obtaining an offset array by adopting a phase comparison method or a traversal comparison method.
The invention provides a phase information-based sweep frequency endoscopic OCT image artifact removal system, which is used for implementing the phase information-based sweep frequency endoscopic OCT image artifact removal method and comprises a sweep frequency light source, an optical imaging catheter, a rotary slip ring and an interference module, wherein the sweep frequency light source is used for generating an OCT sweep frequency signal; further comprises:
the data acquisition module is used for acquiring the original data and the background information data of the sweep OCT;
the phase analysis module is used for carrying out phase analysis after processing the original data; according to the data after phase analysis, selecting any one of the A-line lines as a reference line by adopting a phase comparison method, and calculating phase offset information for other A-line lines to obtain a phase offset array;
the calibration synchronization module is used for bringing the phase shift array into the original data, and calibrating the original data by using the phase shift array to obtain calibrated phase synchronization data;
and the artifact removing module is used for carrying out difference operation by utilizing the background information data and the calibrated phase synchronization data to obtain artifact removed data.
Further preferably, when the data acquisition module acquires the original data of the swept OCT, trigger and clock information are provided from the outside, and at the moment, the swept endoscopic OCT image artifact removal system is a single-channel endoscopic OCT system and further comprises an artifact spike acquisition module and a reverse phase analysis module;
the artifact spike acquisition module is used for acquiring artifact spike information after performing frequency domain transformation on the original data;
the reverse phase analysis module is used for carrying out phase analysis on the acquired artifact spike information and constructing a filter; filtering peak values within a set bandwidth by using the constructed filter; and (3) performing inverse phase analysis on the filtered spike information after utilizing inverse Fourier transform.
Optionally, when the data acquisition module acquires the original data of the swept OCT, trigger and clock information are provided from the inside, and at this time, the swept endoscopic OCT image artifact removal system is a dual-channel endoscopic OCT system, and further includes a k-clock signal analysis module;
the k-clock signal analysis module is used for acquiring phase information by Hilbert transformation aiming at the acquired k-clock data, and combining the dual-channel endoscopic OCT data with the phase information to form a complex signal with the phase information; and obtaining an offset array by adopting a phase comparison method or a traversal comparison method.
The method and the system for removing the image artifact of the sweep frequency endoscopic OCT based on the phase information have the following advantages compared with the prior art:
1. the method solves the problem that the traditional artifact removal algorithm can not completely remove artifacts because the sweep frequency phase of the scanning light source can not be stable and unchanged, and phase offset necessarily exists between each A-line when the A-line data is acquired in a rapid scanning mode.
2. The method is suitable for sweep frequency endoscopic OCT of single-channel and double-channel multiple models, and can remove artifact information caused by joint or reflecting surface or welding due to the fact that optical fiber photoelectric conversion devices are more in connection and switching of hardware.
Drawings
Fig. 1 is a schematic diagram of a method for removing an image artifact of a swept-frequency endoscopic OCT based on phase information according to the present invention;
FIG. 2 is a detailed flowchart of the method for removing the image artifact of the swept-frequency endoscopic OCT based on the phase information according to the present invention;
FIG. 3 is a graph of 1000A-line data in a frame of image, after power spectrum is obtained, the data is drawn and superimposed;
FIG. 4 shows a schematic diagram of filtering a selected reference peak by automatically finding the reference peak, a black line gray filtered bandpass schematic;
FIG. 5 is a plot of raw, non-phase synchronized, all A-line data of the anti-phase analysis of the peaks of FIG. 3;
FIG. 6 is a graph of calculated values of other A-line jumps relative to a fiducial line with reference to the fiducial line;
FIG. 7 is a plot of all A-line data after phase calibration using a phase offset array;
FIG. 8 is a partially enlarged, comparative view of FIGS. 5 and 7;
FIG. 9 is a graph of data after calibration versus the value of data jumps for other A-lines of the baseline;
FIG. 10 is an original image of swept-frequency endoscopic OCT;
FIG. 11 is a diagram of the background subtracted without calibration;
fig. 12 is a graph of background subtraction after phase calibration.
Detailed Description
The invention is described in further detail below with reference to the drawings and the detailed description.
As shown in fig. 1, the method for removing the image artifact of the swept-frequency endoscopic OCT based on phase information according to an embodiment of the present invention includes the following steps:
s1, acquiring background information data before catheter connection and original data of sweep OCT;
s2, processing the original data and then carrying out phase analysis; obtaining a phase shift array according to the data after the phase analysis;
s3, bringing the phase shift array into the original data, and calibrating the original data by using the phase shift array to obtain calibrated phase synchronous data;
and S4, performing difference operation by using the background information data and the calibrated phase synchronization data to obtain artifact-removed data.
On the other hand, the invention provides a sweep frequency endoscopic OCT image artifact removal system based on phase information, which is used for implementing the sweep frequency endoscopic OCT image artifact removal method based on the phase information, and comprises a sweep frequency light source for generating an OCT sweep frequency signal, an optical imaging catheter, a rotary slip ring and an interference module; further comprises:
the data acquisition module is used for acquiring the original data and the background information data of the sweep OCT;
the phase analysis module is used for carrying out phase analysis after processing the original data; according to the data after phase analysis, selecting any one of the A-line lines as a reference line by adopting a phase comparison method, and calculating phase offset information for other A-line lines to obtain a phase offset array;
the calibration synchronization module is used for bringing the phase shift array into the original data, and calibrating the original data by using the phase shift array to obtain calibrated phase synchronization data;
and the artifact removing module is used for carrying out difference operation by utilizing the background information data and the calibrated phase synchronization data to obtain artifact removed data.
Example 1
The single-channel endoscopic OCT system is built, and the single-channel OCT system only collects one signal, and the triggering and clock information are provided by an external module. The system comprises a sweep frequency light source, an optical imaging catheter, a rotating slip ring and an interference module; the system comprises a data acquisition module, a phase analysis module, a calibration synchronization module, an artifact removal module, an artifact spike acquisition module and a reverse phase analysis module, wherein the data acquisition module is used for acquiring an artifact spike;
first, acquisition, calculation, and saving of background data are performed.
Further, the original data of the channel, that is, the original data of the swept OCT, is obtained, and the original data is single-channel endoscopic OCT data. In this embodiment, a single-channel endoscopic OCT system employed when single-channel endoscopic OCT data is acquired is described in detail.
Preferably, a fusion gap can be optionally added to the optical imaging catheter module, or a reflective surface can be added to the detector module to provide a spike signal or no means can be added, but only a spike signal provided by background artifacts.
As shown in fig. 2, the original data of the swept OCT is collected by channel a, and after collection, the data is directly transferred into the system memory. The original data herein refers to lossless data after AD conversion.
In S2, processing the original data and then carrying out phase analysis; obtaining a phase shift array according to the data after the phase analysis;
the specific steps are shown in the left branch of the flow chart of fig. 2:
s210, after carrying out frequency domain transformation on the original data, obtaining artifact spike information;
preferably, first, it is set that one frame of data obtained contains 1000 pieces of a-line data, and then a frequency domain information map is drawn by solving for frequency domain information, as shown in fig. 3. By judging the artifact peak value and grabbing the artifact peak value information, therefore, a threshold value L is set for grabbing the artifact peak value information:
L=S(PowerPeak)/N(Bg) （1）
PowerPeak is the grabbing peak and Bg is the background; s (PowerPeak) is the dominant peak intensity and N (Bg) is the background intensity. After taking the logarithm to be in dB:
the threshold is set at 3dB when
>3, use +.>
Taking the position peak value as a grabbing peak. In addition to determining the threshold of amplitude, the peak search needs to be performed to determine the search range in the xindex direction, where xindex refers to the point coordinates of each a-line. The xindex search range is defined herein as between 100 and 400,
is the peak position.
S220, filtering and anti-phase analysis is conducted on the obtained artifact peak information.
And (3) obtaining the position and amplitude information of the multiple peaks by analyzing peak information, and constructing a filter passfilter, so that the filter filters the peaks within a set bandwidth. As shown in fig. 4, the thickened black lines are in the shape of a filter. And carrying out inverse Fourier transform on the filtered data, and expanding frequency information into time domain information for analysis, wherein the time domain information comprises phase information, amplitude information and signal period information. The calculation formula is as follows:
of the formula (I)
I.e. the original signal of the input,/->
I.e. the filtered signal. />
Is the time domain period information of the peak position. />
The number of valid points for each A-line. />
For the index position of the peak information, the complex signal with phase information can be obtained by calculation +.>
。
An image of the signal obtained after the anti-phase analysis is plotted as shown in fig. 5.
Further, according to the data after phase analysis, a phase comparison method or a traversal comparison method is adopted to obtain a phase offset array;
further, the original data is calibrated by using the phase shift array to obtain calibrated phase synchronization data.
Finally, artifact-removed data is obtained, and the embodiment ends.
Example 2
The specific procedure of the phase comparison method is described below using specific examples. A reference line is selected, which may be any one of lines a-line of 1.2.3 … N or the like, and the other lines than the reference line refer to the reference phase information to compare the phase information. The comparison method is that the N-1 line reference data and the datum line data are integrated, then the phase is calculated, and the phase expansion analysis is carried out. The phase unwrapping can be used to obtain a phase offset array.
The phase information is:
offset array:
wherein the method comprises the steps of
Representing the calculation of the angle>
Representing the sum of the phases after unwrapping, summing the total phases,/->
Refers to the circumference ratio.
Based on the offset array, a calibration array is generated. The elements in the offset array are displacement offsets between lines, the offsets are floating point types, and floating point types are rounded to generate the calibration array.
Example 3
Specific procedures of the traversal method are described below using specific examples. For the line with smaller step degree, the traversing comparison method can be selected for solving. The traversal range is-3, -2, -1, 2,3. The method is specifically implemented by performing positive or negative offset on original data, performing phase comparison with a reference line, and when a comparison value is smaller than 0.5, considering that the offset direction is correct and recording an offset value; and integrating the offset value of each A-line with the corresponding offset direction to form a phase offset array, and performing the same operation on other A-line data in the same way. The method has reduced computational complexity relative to general methods. As shown in FIG. 6, the abscissa indicates the number of each A-line, 1-1000, and 1000A-lines. The ordinate represents pixel values whose phases are shifted in the time domain.
S3, bringing the phase shift array into the original data, and calibrating the original data by using the phase shift array to obtain calibrated phase synchronous data;
after the phase shift array is obtained, the phase shift array is brought into the original data, and phase synchronization is carried out through the operation of the original data and the phase shift array, so that the data after phase synchronization is obtained. Fig. 7 shows the phase synchronized image. Fig. 8 is a partially enlarged detail, the upper part of the diagram represents the signal before phase synchronization, and the lower part of the diagram is the signal after phase synchronization. Fig. 9 shows a graph of phase shift after synchronization is completed, compared with reference lines using all a-line lines.
And S4, performing difference operation by using the background information data and the calibrated phase synchronization data to obtain artifact-removed data.
Because of the different OCT of other modes such as sweep frequency endoscopic OCT and galvanometer, the endoscopic OCT has an optical imaging catheter portion, and when imaging, the wall information can always exist in the image. Thus, in performing the acquisition of the image, an additional setting is to acquire background image information, including optical speckle noise and electrical noise, prior to connecting the catheter. The acquired background information is calculated by taking 1000 pieces of A-line data or other quantity, and the quantity of the A-lines can be tens to thousands, and 1000 pieces of A-lines are selected in the embodiment. And summing all the A-line data and then averaging to obtain the background information.
Artifact removed data. In the step S6, the data are subjected to phase synchronization, and then the data subjected to artifact removal are subjected to difference with the background data. As shown in the three figures of fig. 10, 11 and 12. Fig. 10 shows image information with artifacts, fig. 11 shows an image with direct background subtraction (direct subtraction in the original signal domain with the original signal of fig. 10 as background), and fig. 12 shows the image with phase correction after background subtraction. It is apparent that the figure 11 image does not remove the artifacts well, whereas the figure 12 image is very clean with the background artifacts removed by phase correction.
Example 4, dual channel endoscopic OCT system setup; the method comprises the steps of adopting a dual-channel endoscopic OCT system for data acquisition, wherein the system comprises a sweep frequency light source, an optical imaging catheter, a rotating slip ring and an interference module; the system comprises a data acquisition module, a phase analysis module, a calibration synchronization module, an artifact removal module and a k-clock signal analysis module, wherein when the original data of the sweep OCT is acquired, the data are dual-channel endoscopic OCT data and k-clock data, and the data acquisition is performed by adopting a dual-channel endoscopic OCT system.
First, background data is acquired and calculated and saved.
Then, a dual channel raw data signal and k-clock data are acquired. The original data is the unprocessed A/D data acquired by the channel A channel. The k-clock data is external data provided by the sweep frequency light source module, and the data is accessed to the channel B channel.
Further, a phase comparison method or a traversal method is adopted to obtain an offset array, and k-clock phase analysis is adopted to obtain the offset array. For phase analysis of the data of k-clock, to obtain the phase information of k-clock, hilbert transform may be used to obtain the phase information and then obtain the complex signal with the phase information, and then in step S2, a phase comparison method or a traversal method may be used to obtain the offset array.
Finally, the phase synchronization and the final data after artifact removal are the same as those of example 2.
It is apparent that the above examples are given by way of illustration only and are not limiting of the embodiments. Other variations or modifications of the above teachings will be apparent to those of ordinary skill in the art. It is not necessary here nor is it exhaustive of all embodiments. While still being apparent from variations or modifications that may be made by those skilled in the art are within the scope of the invention.
Claims (8)
1. The method for removing the image artifact of the sweep frequency endoscopic OCT based on the phase information is characterized by comprising the following steps of:
s1, acquiring background information data before catheter connection and original data of sweep OCT;
s2, processing the original data and then carrying out phase analysis; obtaining a phase shift array according to the data after the phase analysis; the method specifically comprises the following steps:
s210, after carrying out frequency domain transformation on the original data, obtaining artifact spike information; the method comprises the following steps:
s211, performing frequency domain transformation on a plurality of A-line data contained in one frame of data in the original data;
s212, setting a threshold function according to the transformed frequency domain information by adopting the following formula, and capturing an artifact peak;
wherein the method comprises the steps of，
For peak grasping Bg is background, +.>
Intensity of main peak, ++>
Is background intensity;
s213, searching an artifact peak according to the index direction and a preset search range by taking the point coordinate of each A-line as a starting point according to a set threshold function, and acquiring the peak position;
s220, carrying out phase analysis on the acquired artifact peak information; the method comprises the following steps:
s221, constructing a filter according to peak position and amplitude information in the acquired peak artifact information;
s222, filtering peak values within a set bandwidth by using the constructed filter;
s223, performing inverse phase analysis on the filtered spike information after inverse Fourier transform;
s3, bringing the phase shift array into the original data, and calibrating the original data by using the phase shift array to obtain calibrated phase synchronous data;
and S4, performing difference operation by using the background information data and the calibrated phase synchronization data to obtain artifact-removed data.
2. The phase information based swept-frequency endoscopic OCT imaging artifact removal method according to claim 1, wherein in S1, the raw data of the acquired swept-frequency OCT includes single-channel endoscopic OCT data or dual-channel endoscopic OCT data and k-clock data.
3. The phase information-based method for removing image artifacts of swept-frequency endoscopic OCT according to claim 2, wherein in S2, when a phase shift array is obtained from the phase-analyzed data, a phase comparison method is used to obtain the phase shift array;
the phase comparison method comprises the steps of selecting any one of the A-line lines as a datum line, and calculating phase offset information for other A-line lines.
4. The phase information-based sweep-frequency endoscopic OCT image artifact removal method according to claim 2, wherein in S2, when obtaining a phase shift array according to the phase analyzed data, a traversal contrast method is used to obtain the phase shift array;
the traversal comparison method comprises the steps of selecting any one of the A-line lines as a datum line, performing positive or negative offset on other A-line lines in original data, performing phase comparison with the datum line, considering that the offset direction is correct when a comparison value is smaller than a preset threshold value, and recording an offset value; and integrating the offset value of each A-line with the corresponding offset direction to form a phase offset array.
5. The phase information-based swept-frequency endoscopic OCT image artifact removal method according to claim 2, wherein when the raw data of the acquired swept-frequency OCT is dual-channel endoscopic OCT data and k-clock data, in S2, the phase information is acquired for the acquired k-clock data by using hilbert transform
Combining the dual-channel endoscopic OCT data with the phase information to form a complex signal with the phase information; and obtaining an offset array by adopting a phase comparison method or a traversal comparison method.
6. A phase information-based sweep-frequency endoscopic OCT image artifact removal system, which is characterized by being used for implementing the phase information-based sweep-frequency endoscopic OCT image artifact removal method according to any one of claims 1-5, and comprising a sweep-frequency light source for generating an OCT sweep signal, an optical imaging catheter, a rotating slip ring, and an interference module; further comprises:
the data acquisition module is used for acquiring the original data and the background information data of the sweep OCT;
the phase analysis module is used for carrying out phase analysis after processing the original data; according to the data after phase analysis, selecting any one of the A-line lines as a reference line by adopting a phase comparison method, and calculating phase offset information for other A-line lines to obtain a phase offset array;
the calibration synchronization module is used for bringing the phase shift array into the original data, and calibrating the original data by using the phase shift array to obtain calibrated phase synchronization data;
and the artifact removing module is used for carrying out difference operation by utilizing the background information data and the calibrated phase synchronization data to obtain artifact removed data.
7. The phase information-based swept-frequency endoscopic OCT image artifact removal system of claim 6, wherein when the data acquisition module acquires the original data of the swept-frequency OCT, trigger and clock information are provided from the outside, and the swept-frequency endoscopic OCT image artifact removal system is a single-channel endoscopic OCT system, and further comprising an artifact spike acquisition module and a reverse phase analysis module;
the artifact spike acquisition module is used for acquiring artifact spike information after performing frequency domain transformation on the original data;
the reverse phase analysis module is used for carrying out phase analysis on the acquired artifact spike information and constructing a filter; filtering peak values within a set bandwidth by using the constructed filter; and (3) performing inverse phase analysis on the filtered spike information after utilizing inverse Fourier transform.
8. The phase information-based sweep frequency endoscopic OCT image artifact removal system of claim 7, wherein when the data acquisition module acquires the original data of the sweep frequency OCT, trigger and clock information are provided internally, and the sweep frequency endoscopic OCT image artifact removal system is a dual-channel endoscopic OCT system, further comprising a k-clock signal analysis module, wherein the k-clock signal analysis module acquires phase information by hilbert transformation for the acquired data of the k-clock, and combines the dual-channel endoscopic OCT data with the phase information to form a complex signal with the phase information; and obtaining an offset array by adopting a phase comparison method or a traversal comparison method.
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