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CN116989699B - A high dynamic range fringe projection 3D measurement method based on fringe restoration - Google Patents

A high dynamic range fringe projection 3D measurement method based on fringe restoration

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CN116989699B
CN116989699B CN202310957009.0A CN202310957009A CN116989699B CN 116989699 B CN116989699 B CN 116989699B CN 202310957009 A CN202310957009 A CN 202310957009A CN 116989699 B CN116989699 B CN 116989699B
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fringe
csi
bsi
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CN116989699A (en
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李洪儒
韦豪
刘江涛
邓国亮
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Sichuan University
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    • G—PHYSICS
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    • G06T5/00—Image enhancement or restoration
    • G06T5/20—Image enhancement or restoration using local operators
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    • G01B11/00—Measuring arrangements characterised by the use of optical techniques
    • G01B11/24—Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures
    • G01B11/25—Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures by projecting a pattern, e.g. one or more lines, moiré fringes on the object
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
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    • G01B11/24—Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures
    • G01B11/25—Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures by projecting a pattern, e.g. one or more lines, moiré fringes on the object
    • G01B11/254—Projection of a pattern, viewing through a pattern, e.g. moiré
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B11/00—Measuring arrangements characterised by the use of optical techniques
    • G01B11/24—Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures
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    • G06T3/00—Geometric image transformations in the plane of the image
    • G06T3/40—Scaling of whole images or parts thereof, e.g. expanding or contracting
    • G06T3/4007—Scaling of whole images or parts thereof, e.g. expanding or contracting based on interpolation, e.g. bilinear interpolation

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Abstract

The invention provides a high dynamic range stripe projection three-dimensional measurement method based on stripe restoration, which comprises the following steps of projecting a multi-step gray level sine stripe graph to a high reflection surface, dividing a shot image into a reliable region, a shallow saturation region and a deep saturation region, calculating A, B curved surfaces of the reliable region by using an Euler formula method, finding unsaturated lower intersection points between adjacent stripes to expand F lower curved surfaces, supplementing shallow and deep saturation regions of the three surfaces by using a CSI-BSI interpolation method, calculating accurate A of each position according to the relation between the shallow and deep saturation regions, and restoring the saturated stripes to further calculate phases. The high dynamic range stripe projection three-dimensional measurement method based on stripe repair, provided by the invention, can be used for effectively repairing saturated stripes, improving the dynamic range of a system, increasing the information utilization rate of each image by using the stripe repair method, reducing the number of patterns to be projected for high dynamic range measurement, and effectively improving the measurement speed.

Description

High dynamic range stripe projection three-dimensional measurement method based on stripe repair
Technical Field
The invention relates to the field of structured light three-dimensional measurement, in particular to a high dynamic range stripe projection three-dimensional measurement method based on stripe repair.
Background
With the development of science and technology, three-dimensional information of objects is more and more paid attention to, and stripe projection three-dimensional measurement technology is widely applied to multiple fields of industrial modeling, cultural relic protection, biomedicine, intelligent driving and the like.
With the wider and wider application of structured light three-dimensional measurement, the characteristics of the measured object are more complex, the object to be measured is not limited to a white or light object, and sometimes the object with larger change of the reflectivity of the object surface is required to be measured.
Because the dynamic range of the camera is limited, the shot fringe pattern can be saturated, and if the direct calculation phase is deviated from the ideal phase after the fringe is saturated, the three-dimensional measurement is inaccurate.
Therefore, it is necessary to provide a high dynamic range fringe projection three-dimensional measurement method based on fringe restoration to solve the above technical problems.
Disclosure of Invention
The invention provides a high dynamic range stripe projection three-dimensional measurement method based on stripe restoration, which solves the problem that the existing camera has limited dynamic range, a shot stripe image is saturated, and if a direct calculated phase is deviated from an ideal phase after the stripe is saturated, the three-dimensional measurement is inaccurate.
In order to solve the technical problems, the high dynamic range stripe projection three-dimensional measurement method based on stripe repair provided by the invention comprises the following steps:
s1, projecting a multi-step gray sine fringe pattern to a high-reflection surface, and collecting multi-step phase shift deformation saturated fringes by a CCD;
s2, dividing a shot image into a reliable region, a shallow saturation region and a deep saturation region, calculating the reliable region by using a multi-step phase shift saturation fringe pattern, and calculating A, B parameters of the reliable region by using an Euler formula method;
S3, because the shallow saturation region and the deep saturation region cannot be solved perfectly, expanding and corroding all reliable regions, obtaining a CSI and BSI region of A, B to approximately correspond to the shallow saturation region and the deep saturation region of A, B, and interpolating and complementing A, B of the CSI and BSI regions by using a CSI and BSI interpolation method;
S4, finding unsaturated lower intersection points between adjacent stripes, wherein the curved surfaces where the points are located are F lower, using the lower intersection points as reliable points of F lower, using the relation between A, B and F lower, expanding the reliable points of F lower by A, B of the reliable point positions, finally expanding and corroding the expanded reliable areas of F lower to obtain CSI and BSI areas of F lower so as to approximately correspond to shallow saturation areas and deep saturation areas of F lower, and interpolating and complementing F lower of the CSI and BSI areas by using a CSI and BSI interpolation method;
s5, calculating an accurate A of each position by utilizing A, B and F lower obtained by interpolation according to the relation between the three curved surfaces A, B and F lower;
s6, repairing the saturated stripes by using the relationship among the stripes, namely repairing the saturated stripes by using the repaired A and the unsaturated stripes, and complementing the rest parts by using CSI interpolation after the saturated parts at the tops of the stripes are repaired;
s7, calculating phases by using a multi-step phase shift method after all stripes are repaired;
and S8, solving the orders by using a complementary Gray code method and expanding the wrapping phase.
Preferably, the step S1 includes the following specific steps:
S1, projecting a gray sine fringe pattern on a high-reflection surface, acquiring deformed saturated fringe by a CCD, projecting N fringe patterns with constant phase difference delta, and shooting images with phase difference delta, namely,
Wherein, the N is the number of phase shift steps, which is an integer greater than or equal to 3, n=1, 2.
Preferably, the step S2 includes the following specific steps:
S21, dividing each point in the image into a reliable region, a shallow saturation region and a deep saturation region according to the saturation condition of the N phase shift maps. If three or more of the N phase shift maps are taken at a certain point, the value of which is less than 255, the point is a reliable region, and the rest is an unreliable region. Assuming a a as the actual a parameter in the unreliable region, then the point is the shallow saturation region when a a <255 and the point is the deep saturation region when a a is ≡255.
S22, directly solving the A parameters of the reliable region, wherein the A parameters of the shallow saturation region and the deep saturation region cannot be directly solved, and the A parameter solving formula of the reliable region is as follows:
According to Euler equation e ix＝cosx+isinx,In (x, y) can be written as:
The stripe with stripe subscript n 1,n2,...,nk is not saturated and these equations for the unsaturated stripes at the simultaneous (x, y) position:
Then the a, B parameter solving formula is:
Preferably, the step S3 includes the following specific steps:
s31, after the A, B reliable areas are solved, the reliable areas are expanded, and the expansion distance is more than half of the fringe period, so that the expansion areas are obtained;
then corroding the expansion area, wherein the corrosion distance is larger than the expansion distance, so as to obtain a CSI area;
Finally, reversing the CSI region to obtain a BSI region, wherein the CSI region and the BSI region are obtained to approximately correspond to the shallow saturation region and the deep saturation region because the shallow saturation region and the deep saturation region cannot be solved perfectly;
S32, interpolation complement is carried out on the A value of the whole CSI region by taking the A values of all the reliable points in the CSI region as the basis;
interpolation complement is carried out on the B value of the whole CSI region by taking the B values of all the reliable points in the CSI region as the basis;
The interpolation method uses a cubic spline interpolation method cubic spline interpolation, which is simply called as a CSI interpolation method;
s33, interpolation is carried out on the A value of the whole BSI area by taking the A values of all the reliable points in the BSI area as the basis;
Interpolation complement is carried out on the B values of the whole BSI area by taking the B values of all the reliable points in the BSI area as the basis;
The interpolation method uses a bi-tone and spline interpolation method biharmonic spline interpolation, abbreviated as BSI interpolation method.
Preferably, the step S4 includes the following specific steps:
The method for searching the reliable points of S41 and F lower is as follows, the reliable points are the lower intersection points where adjacent stripes are not saturated and the lower reliable points calculated by the reliable areas of A and B, and for the adjacent stripes I n (x, y) and I n+1 (x, y), the equation of the intersection point positions is as follows:
Solving the above equation, the phase of the intersection point position is:
the stripe intensity values at the intersection point positions are:
k is an integer, and in order to determine whether these intersections are lower intersections, the intersection intensity magnitudes of the symmetric fringes of I n (x, y) and I n+1 (x, y) at that location are used to assist in the determination;
The symmetric stripes of I n (x, y) and I n+1 (x, y) are denoted as I MOD(N/2+n) and I MOD(N/2+n+1), where 'MOD' borrows the concept of a remainder function, denoted as:
N represents the total number of phase shift steps and the intensity of the symmetric stripe intersections is expressed as:
Determination of The condition that the point is the lower intersection point P lower int is:
all lower intersections of all F lower are the union of all adjacent stripe intersections:
in addition, the reliable point position a, B can further expand the reliable point of F lower by the following formula:
S42, after solving the F lower reliable area, expanding the reliable area, wherein the expansion distance is more than half of the fringe period, and obtaining an expanded area;
then corroding the expansion area, wherein the corrosion distance is larger than the expansion distance, so as to obtain a CSI area;
Finally, reversing the CSI region to obtain a BSI region;
Because the shallow saturation region and the deep saturation region cannot be solved perfectly, the CSI and BSI regions are obtained to approximately correspond to the shallow saturation region and the deep saturation region;
S43, interpolating and complementing the F lower value of the whole CSI region by taking the F lower values of all reliable points in the CSI region as the basis;
The interpolation method uses a cubic spline interpolation method cubic spline interpolation, which is simply called as a CSI interpolation method;
and S44, interpolating and complementing the F lower value of the whole BSI area by using the F lower values of all the reliable points in the BSI area as the basis, wherein the interpolation method uses a bi-tone and spline interpolation method biharmonic spline interpolation, which is called as BSI interpolation method for short.
Preferably, the step S5 includes the following specific steps:
S51, in the interpolated curved surfaces A, B and F lower, the intensity of A, B is higher, the interpolation basic points are few, the interpolation basic points are large and even, the interpolation basic points of F lower are small, the ideal curved surface errors are small, the interpolated curved surface A, B, F lower is written as A ', B', F lo′wer, the ideal curved surface is A, B, F lower, and the gradient can be reserved when the interpolation function interpolates two groups of different intensity points with the same trend, so the ratio of A ', B' is very close to the ratio of A and B:
so the curve A 'and B' with small error with the ideal curve A and B can be solved:
Preferably, the step S6 includes the following specific steps:
When a certain image is saturated in the S61 and N-step phase shift, the restoration formula of the stripe restoration value I n r of the saturated region is as follows:
When N is even number:
When N is an odd number:
s62, after the saturated phase shift image is repaired by using the repairing formula, if saturated positions exist, interpolation is carried out on the positions by using a CSI interpolation method on the basis of the global unsaturated stripe value and the repaired stripe value.
Preferably, the step S7 includes the following specific steps:
s71, the wrapping phase can be obtained through repairing N fringe patterns:
the phase obtained by the above equation is a wrapping phase, which can be unwrapped by an absolute phase method using an unwrapped phase to obtain the height information.
Preferably, the step S8 includes the following specific steps:
s81, projecting a plurality of Gray code fringe patterns on the surface of a high-reflectivity object, acquiring Gray code fringe patterns by using a CCD, calculating the orders by using the first several patterns, and correcting the orders by using the last pattern to obtain the orders K of the fringes;
S82, unfolding the wrapping phase by using the level K, wherein an unfolding formula is as follows:
The resulting phi (x, y) is the unwrapped phase.
Compared with the related art, the high dynamic range stripe projection three-dimensional measurement method based on stripe repair has the following beneficial effects:
The invention provides a high dynamic range stripe projection three-dimensional measurement method based on stripe repair, which can effectively repair saturated stripes, improve the dynamic range of a system, increase the information utilization rate of each image by using the stripe repair method, reduce the number of patterns to be projected for high dynamic range measurement and effectively improve the measurement speed.
Drawings
FIG. 1 is a schematic diagram of a high dynamic range fringe projection three-dimensional measurement method based on fringe restoration according to a preferred embodiment of the present invention;
FIG. 2 is a schematic diagram of the calculation of intersection points under adjacent stripes;
fig. 3 is a graph comparing calculated phases before and after stripe repair.
Detailed Description
The invention will be further described with reference to the drawings and embodiments.
First embodiment
Referring to fig. 1, fig. 2 and fig. 3 in combination, fig. 1 is a schematic structural diagram of a preferred embodiment of a high dynamic range stripe projection three-dimensional measurement method based on stripe repair according to the present invention, fig. 2 is a schematic diagram of intersection point calculation under adjacent stripes, and fig. 3 is a comparative diagram of calculated phases before and after stripe repair. A high dynamic range stripe projection three-dimensional measurement method based on stripe repair comprises the following steps:
s1, projecting a multi-step gray sine fringe pattern to a high-reflection surface, and collecting multi-step phase shift deformation saturated fringes by a CCD;
s2, dividing a shot image into a reliable region, a shallow saturation region and a deep saturation region, calculating the reliable region by using a multi-step phase shift saturation fringe pattern, and calculating A, B parameters of the reliable region by using an Euler formula method;
S3, because the shallow saturation region and the deep saturation region cannot be solved perfectly, expanding and corroding all reliable regions, obtaining a CSI and BSI region of A, B to approximately correspond to the shallow saturation region and the deep saturation region of A, B, and interpolating and complementing A, B of the CSI and BSI regions by using a CSI and BSI interpolation method;
S4, finding unsaturated lower intersection points between adjacent stripes, wherein the curved surfaces where the points are located are F lower, using the lower intersection points as reliable points of F lower, using the relation between A, B and F lower, expanding the reliable points of F lower by A, B of the reliable point positions, finally expanding and corroding the expanded reliable areas of F lower to obtain CSI and BSI areas of F lower so as to approximately correspond to shallow saturation areas and deep saturation areas of F lower, and interpolating and complementing F lower of the CSI and BSI areas by using a CSI and BSI interpolation method;
s5, calculating an accurate A of each position by utilizing A, B and F lower obtained by interpolation according to the relation between the three curved surfaces A, B and F lower;
s6, repairing the saturated stripes by using the relationship among the stripes, namely repairing the saturated stripes by using the repaired A and the unsaturated stripes, and complementing the rest parts by using CSI interpolation after the saturated parts at the tops of the stripes are repaired;
s7, calculating phases by using a multi-step phase shift method after all stripes are repaired;
and S8, solving the orders by using a complementary Gray code method and expanding the wrapping phase.
Please refer to fig. 1:
Step a, projecting a gray sine fringe pattern to a high-reflection surface, and acquiring deformed saturated fringes by a CCD;
Step b, solving parameters A, B of the reliable area and the reliable area;
c, calculating the CSI and BSI areas of A, B by expansion corrosion, and interpolating and complementing A, B of the CSI and BSI areas by using a CSI-BSI interpolation method;
step d, finding a reliable point of the F lower, calculating the CSI and BSI areas of the F lower by expansion corrosion, and interpolating and complementing the F lower of the CSI and BSI areas by using a CSI-BSI interpolation method;
Step e, calculating an accurate A of each position by utilizing A, B and F lower obtained by interpolation;
F, repairing the saturated stripes with the repaired A and the unsaturated stripes, and complementing the rest part by using CSI interpolation;
step g, calculating a wrapping phase by a multi-step phase shift method;
And h, expanding the wrapping phase by a complementary Gray code method.
Second embodiment
The specific steps of the step a are as follows:
and a step a1, encoding N sine stripe patterns as a projection image group.
The phase shift stripe encoding formula is:
Where N is the number of phase steps, n=1, 2,..n is the phase shift number, f 0 is the set fringe frequency, and a, b are typically set to 127.5.
The S1 comprises the following specific steps:
S1, projecting a gray sine fringe pattern on a high-reflection surface, acquiring deformed saturated fringe by a CCD, projecting N fringe patterns with constant phase difference delta, and shooting images with phase difference delta, namely,
Wherein, the N is the number of phase shift steps, which is an integer greater than or equal to 3, n=1, 2.
Third embodiment
The step S2 comprises the following specific steps:
S21, dividing each point in the image into a reliable region, a shallow saturation region and a deep saturation region according to the saturation condition of the N phase shift maps. If three or more of the N phase shift maps are taken at a certain point, the value of which is less than 255, the point is a reliable region, and the rest is an unreliable region. Assuming a a as the actual a parameter in the unreliable region, then the point is the shallow saturation region when a a <255 and the point is the deep saturation region when a a is ≡255.
S22, directly solving the A parameters of the reliable region, wherein the A parameters of the shallow saturation region and the deep saturation region cannot be directly solved, and the A parameter solving formula of the reliable region is as follows:
According to Euler equation e ix＝cosx+isinx,In (x, y) can be written as:
The stripe with stripe subscript n 1,n2,...,nk is not saturated and these equations for the unsaturated stripes at the simultaneous (x, y) position:
Then the a, B parameter solving formula is:
fourth embodiment
The step S3 comprises the following specific steps:
s31, after the A, B reliable areas are solved, the reliable areas are expanded, and the expansion distance is more than half of the fringe period, so that the expansion areas are obtained;
then corroding the expansion area, wherein the corrosion distance is larger than the expansion distance, so as to obtain a CSI area;
Finally, reversing the CSI region to obtain a BSI region, wherein the CSI region and the BSI region are obtained to approximately correspond to the shallow saturation region and the deep saturation region because the shallow saturation region and the deep saturation region cannot be solved perfectly;
S32, interpolation complement is carried out on the A value of the whole CSI region by taking the A values of all the reliable points in the CSI region as the basis;
interpolation complement is carried out on the B value of the whole CSI region by taking the B values of all the reliable points in the CSI region as the basis;
The interpolation method uses a cubic spline interpolation method cubic spline interpolation, which is simply called as a CSI interpolation method;
s33, interpolation is carried out on the A value of the whole BSI area by taking the A values of all the reliable points in the BSI area as the basis;
Interpolation complement is carried out on the B values of the whole BSI area by taking the B values of all the reliable points in the BSI area as the basis;
The interpolation method uses a bi-tone and spline interpolation method biharmonic spline interpolation, abbreviated as BSI interpolation method.
The step S4 comprises the following specific steps:
The method for searching the reliable points of S41 and F lower is as follows, the reliable points are the lower intersection points where adjacent stripes are not saturated and the lower reliable points calculated by the reliable areas of A and B, and for the adjacent stripes I n (x, y) and I n+1 (x, y), the equation of the intersection point positions is as follows:
Solving the above equation, the phase of the intersection point position is:
the stripe intensity values at the intersection point positions are:
k is an integer, and in order to determine whether these intersections are lower intersections, the intersection intensity magnitudes of the symmetric fringes of I n (x, y) and I n+1 (x, y) at that location are used to assist in the determination;
The symmetric stripes of I n (x, y) and I n+1 (x, y) are denoted as I MOD(N/2+n) and I MOD(N/2+n+1), where 'MOD' borrows the concept of a remainder function, denoted as:
N represents the total number of phase shift steps and the intensity of the symmetric stripe intersections is expressed as:
Determination of The condition that the point is the lower intersection point P lower int is:
all lower intersections of all F lower are the union of all adjacent stripe intersections:
in addition, the reliable point position a, B can further expand the reliable point of F lower by the following formula:
S42, after solving the F lower reliable area, expanding the reliable area, wherein the expansion distance is more than half of the fringe period, and obtaining an expanded area;
then corroding the expansion area, wherein the corrosion distance is larger than the expansion distance, so as to obtain a CSI area;
Finally, reversing the CSI region to obtain a BSI region;
Because the shallow saturation region and the deep saturation region cannot be solved perfectly, the CSI and BSI regions are obtained to approximately correspond to the shallow saturation region and the deep saturation region;
S43, interpolating and complementing the F lower value of the whole CSI region by taking the F lower values of all reliable points in the CSI region as the basis;
The interpolation method uses a cubic spline interpolation method cubic spline interpolation, which is simply called as a CSI interpolation method;
and S44, interpolating and complementing the F lower value of the whole BSI area by using the F lower values of all the reliable points in the BSI area as the basis, wherein the interpolation method uses a bi-tone and spline interpolation method biharmonic spline interpolation, which is called as BSI interpolation method for short.
The step S5 comprises the following specific steps:
S51, in the interpolated curved surfaces A, B and F lower, the intensity of A, B is higher, the interpolation basic points are few, the interpolation basic points are large and even, the interpolation basic points of F lower are small, the ideal curved surface errors are small, the interpolated curved surface A, B, F lower is written as A ', B', F lo′wer, the ideal curved surface is A, B, F lower, and the gradient can be reserved when the interpolation function interpolates two groups of different intensity points with the same trend, so the ratio of A ', B' is very close to the ratio of A and B:
so the curve A 'and B' with small error with the ideal curve A and B can be solved:
The step S6 comprises the following specific steps:
When a certain image is saturated in the S61 and N-step phase shift, the restoration formula of the stripe restoration value I n r of the saturated region is as follows:
When N is even number:
When N is an odd number:
s62, after the saturated phase shift image is repaired by using the repairing formula, if saturated positions exist, interpolation is carried out on the positions by using a CSI interpolation method on the basis of the global unsaturated stripe value and the repaired stripe value.
The step S7 comprises the following specific steps:
s71, the wrapping phase can be obtained through repairing N fringe patterns:
the phase obtained by the above equation is a wrapping phase, which can be unwrapped by an absolute phase method using an unwrapped phase to obtain the height information.
The step S8 comprises the following specific steps:
s81, projecting a plurality of Gray code fringe patterns on the surface of a high-reflectivity object, acquiring Gray code fringe patterns by using a CCD, calculating the orders by using the first several patterns, and correcting the orders by using the last pattern to obtain the orders K of the fringes;
S82, unfolding the wrapping phase by using the level K, wherein an unfolding formula is as follows:
The resulting phi (x, y) is the unwrapped phase.
Fifth embodiment
The specific steps of the step d are as follows:
In step d1, find the lower intersection point where the adjacent stripe is not saturated, taking the four-step phase shift as an example, as shown in fig. 2, and fig. 2a shows the positions of all the upper intersection points and the lower intersection points in the four-step phase shift.
FIG. 2b illustrates the process of determining the upper and lower intersection points, using I 1 and I 2 as examples, which are used to retrieve values on symmetrically-located stripes, with the intersection points represented by solid pointsRepresenting reference points by open dotsWill intersectAnd reference pointAnd a comparison is made between them to determine whether they are up or down. When (when)The value of the crossing point is higher than the reference point, expressed as an upper crossing point, conversely, whenWhen the intersection point is lower than the reference point, it is expressed as a lower intersection point. It is emphasized, however, that when the saturation level is high,May not exist, in which case, ifIf not present, the intersection pointStill, should be considered as the lower intersection, the upper and lower intersection of I 1 and I 2, respectively, are found using the methods described above.
Fig. 3 is a phase contrast diagram calculated before and after stripe repair, and it can be seen that after stripe saturation repair, the calculated phase error is obviously reduced, the precision is improved, and no extra stripe projection and equipment assistance are needed, so that the measurement speed is high, and the equipment is simple.
The high dynamic range stripe projection three-dimensional measurement method based on stripe repair has the following beneficial effects:
The method can effectively repair saturated stripes, improves the dynamic range of a system, increases the information utilization rate of each image by using the stripe repair method, reduces the number of patterns to be projected for high dynamic range measurement, and effectively improves the measurement speed.
The foregoing description is only illustrative of the present invention and is not intended to limit the scope of the invention, and all equivalent structures or equivalent processes or direct or indirect application in other related technical fields are included in the scope of the present invention.

Claims (6)

1.一种基于条纹修复的高动态范围条纹投影三维测量方法，其特征在于，包括以下步骤：1. A high dynamic range fringe projection three-dimensional measurement method based on fringe restoration, characterized by comprising the following steps: S1、向高反光表面投影多步灰度正弦条纹图，CCD采集多步相移变形饱和条纹；S1, projecting a multi-step grayscale sinusoidal fringe pattern onto a highly reflective surface, and the CCD captures the multi-step phase-shifted, deformed, saturated fringes; S2、将拍摄的图像分为：可靠区域、浅饱和区域和深饱和区域，用多步相移饱和条纹图计算出可靠区域，用欧拉公式法计算出可靠区域的A、B参数；S2. Divide the captured image into reliable areas, shallow saturation areas, and deep saturation areas. Calculate the reliable areas using a multi-step phase-shift saturation fringe pattern. Calculate the A and B parameters of the reliable areas using the Euler formula method. S3、由于浅饱和区域和深饱和区域不能完美求解，对所有可靠区域膨胀和腐蚀，获得A、B的CSI和BSI区域来对应A、B的浅饱和区域和深饱和区域并利用CSI和BSI插值方法对CSI和BSI区域的A、B进行插值补全；S3. Since the shallow saturation region and the deep saturation region cannot be perfectly solved, all reliable regions are expanded and eroded to obtain the CSI and BSI regions of A and B corresponding to the shallow saturation region and the deep saturation region of A and B. The CSI and BSI interpolation methods are then used to interpolate and complete the CSI and BSI regions of A and B. S4、找到相邻条纹之间的非饱和下交点，这些点所在的曲面为Flower，将这些下交点作为Flower的可靠点，并用A、B和Flower的关系，用可靠点位置的A、B扩充Flower的可靠点，最后利用Flower的扩展可靠区域膨胀和腐蚀，获得Flower的CSI和BSI区域来对应Flower的浅饱和区域和深饱和区域并利用CSI和BSI插值方法对CSI和BSI区域的Flower进行插值补全；S4. Find the unsaturated lower intersection points between adjacent stripes. The surface where these points are located is F lower . Use these lower intersection points as reliable points of F lower . Use the relationship between A, B, and F lower to expand the reliable points of F lower using A and B at the reliable point positions. Finally, use the expanded reliable area of F lower to expand and erode to obtain the CSI and BSI areas of F lower to correspond to the shallow saturation area and deep saturation area of F lower . Use the CSI and BSI interpolation methods to interpolate and complete F lower in the CSI and BSI areas. S5、根据A、B和Flower三个曲面之间的关系，利用插值得到的A、B和Flower计算出每个位置准确的A；S5. According to the relationship between the three surfaces A, B and F lower , the accurate A at each position is calculated using the interpolated A, B and F lower ; S6、利用条纹之间的关系，用修复的A以及没有饱和的条纹对饱和条纹进行修复，当条纹顶部饱和的部分被修复后，其余部分使用CSI插值来补全；S6. Using the relationship between stripes, the saturated stripes are repaired using the repaired A and the unsaturated stripes. After the saturated portion at the top of the stripe is repaired, the remaining portion is completed using CSI interpolation. S7、当所有条纹被修复后使用多步相移法计算相位；S7, when all fringes are repaired, use the multi-step phase shift method to calculate the phase; S8、使用互补格雷码方法求解级次并展开包裹相位；S8, using the complementary Gray code method to solve the order and unfold the wrapped phase; 所述S1包括以下具体步骤：The S1 includes the following specific steps: S1、向高反光表面投影灰度正弦条纹图，CCD采集变形饱和条纹，投影的N幅有恒定相位差δ的条纹图，拍摄到的图像也有δ的相位差，即，S1, projecting a grayscale sinusoidal fringe pattern onto a highly reflective surface, the CCD collects the deformed saturated fringes, the projected N fringe patterns have a constant phase difference δ, and the captured image also has a phase difference of δ, that is, 其中，N为相移步数，是大于等于3的整数，n＝1,2,...,N为相移序号，A(x,y)为平均强度，B(x,y)为强度调制，为物体相位；in, N is the number of phase shift steps, which is an integer greater than or equal to 3, n = 1, 2, ..., N is the phase shift sequence, A (x, y) is the average intensity, B (x, y) is the intensity modulation, is the object phase; 所述S3包括以下具体步骤：The S3 includes the following specific steps: S31、求解到A、B可靠区域后，对可靠区域进行膨胀，膨胀距离应该超过条纹周期的一半，获得膨胀区域；S31, after solving the reliable regions A and B, the reliable regions are expanded. The expansion distance should be more than half of the fringe period to obtain the expanded region; 然后对膨胀区域进行腐蚀，腐蚀距离应该大于膨胀距离，获得CSI区域；Then the expanded area is eroded, and the erosion distance should be greater than the expansion distance to obtain the CSI area; 最后对CSI区域进行反转得到BSI区域，由于浅饱和区域和深饱和区域不能完美求解，获得CSI和BSI区域来对应浅饱和区域和深饱和区域；Finally, the CSI region is inverted to obtain the BSI region. Since the shallow saturation region and the deep saturation region cannot be perfectly solved, the CSI and BSI regions are obtained to correspond to the shallow saturation region and the deep saturation region; S32、用CSI区域内的所有可靠点的A值为基础对CSI整个区域的A值进行插值补全；S32. Using the A values of all reliable points in the CSI area as a basis, interpolate and complete the A value of the entire CSI area. 用CSI区域内的所有可靠点的B值为基础对CSI整个区域的B值进行插值补全；Interpolate and complete the B value of the entire CSI area based on the B values of all reliable points in the CSI area; 插值方法使用三次样条插值方法：cubic spline interpolation，简称为CSI插值方法；The interpolation method uses the cubic spline interpolation method: cubic spline interpolation, referred to as CSI interpolation method; S33、用BSI区域内所有可靠点的A值为基础对BSI整个区域的A值进行插值补全；S33, using the A values of all reliable points in the BSI area as a basis, interpolating and completing the A value of the entire BSI area; 用BSI区域内所有可靠点的B值为基础对BSI整个区域的B值进行插值补全；The B values of all reliable points in the BSI area are used as the basis to interpolate and complete the B values of the entire BSI area; 插值方法使用双调和样条插值方法：biharmonic spline interpolation，简称为BSI插值方法；The interpolation method uses the biharmonic spline interpolation method: biharmonic spline interpolation, referred to as BSI interpolation method; 所述S4包括以下具体步骤：The S4 includes the following specific steps: S41、Flower的可靠点寻找方法如下，可靠点就是相邻条纹没有饱和的下交点以及A，B的可靠区域计算的下可靠点，对于相邻条纹In(x,y)和In+1(x,y)，其交点位置的方程为：The method for finding the reliable point of S41 and F lower is as follows. The reliable point is the lower intersection point of adjacent stripes without saturation and the lower reliable point calculated from the reliable areas of A and B. For the adjacent stripes In (x, y) and In +1 (x, y), the equation for the intersection position is: 求解上式，交点位置的相位为：Solving the above equation, the phase of the intersection position is: 交点位置的条纹强度值为：The fringe intensity value at the intersection position is: k为整数，为了判定这些交点是否是下交点，用In(x,y)和In+1(x,y)的对称条纹在该位置的交点强度大小来辅助判定；k is an integer. In order to determine whether these intersection points are lower intersection points, the intersection intensity of the symmetrical stripes of In (x, y) and In +1 (x, y) at the location is used to assist in the determination. In(x,y)和In+1(x,y)的对称条纹表示为IMOD(N/2+n)和IMOD(N/2+n+1)，其中‘MOD’借用了取余函数的概念，表示为：The symmetrical stripes of In (x, y) and In +1 (x, y) are expressed as I MOD(N/2+n) and I MOD(N/2+n+1) , where 'MOD' borrows the concept of the modulo function and is expressed as: N表示总的相移步数，对称条纹交点的强度表示为：N represents the total number of phase shift steps, and the intensity of the symmetrical fringe intersection is expressed as: 判定点为下交点Plowerint的条件为：determination The condition for the point to be the lower intersection point P lowerint is: is theif is the if is theif is the if 所有的Flower的所有下交点为所有相邻条纹交点的并集：All lower intersections of all F lowers are the union of all adjacent stripe intersections: 另外，可靠点位置的A，B也能够对Flower的可靠点进行进一步扩充，扩充的公式为：In addition, the reliable points A and B can also further expand the reliable points of F lower . The expansion formula is: S42、求解到Flower可靠区域后，对可靠区域进行膨胀，膨胀距离应该超过条纹周期的一半，获得膨胀区域；S42, after solving the F lower reliable region, dilate the reliable region, the dilation distance should be greater than half of the fringe period, and obtain the dilated region; 然后对膨胀区域进行腐蚀，腐蚀距离应该大于膨胀距离，获得CSI区域；Then the expanded area is eroded, and the erosion distance should be greater than the expansion distance to obtain the CSI area; 最后对CSI区域进行反转得到BSI区域；Finally, the CSI region is inverted to obtain the BSI region; 由于浅饱和区域和深饱和区域不能完美求解，获得CSI和BSI区域来对应浅饱和区域和深饱和区域；Since the shallow saturation region and the deep saturation region cannot be solved perfectly, the CSI and BSI regions are obtained to correspond to the shallow saturation region and the deep saturation region; S43、用CSI区域内的所有可靠点的Flower值为基础对CSI整个区域的Flower值进行插值补全；S43. Using the F lower values of all reliable points in the CSI area as a basis, interpolate and complete the F lower value of the entire CSI area. 插值方法使用三次样条插值方法：cubic spline interpolation，简称为CSI插值方法；The interpolation method uses the cubic spline interpolation method: cubic spline interpolation, referred to as CSI interpolation method; S44、用BSI区域内所有可靠点的Flower值为基础对BSI整个区域的Flower值进行插值补全，插值方法使用双调和样条插值方法：biharmonic spline interpolation，简称为BSI插值方法。S44. Using the F lower values of all reliable points in the BSI area as a basis, interpolating and completing the F lower value of the entire BSI area, the interpolation method uses a biharmonic spline interpolation method: biharmonic spline interpolation method, referred to as the BSI interpolation method. 2.根据权利要求1所述的基于条纹修复的高动态范围条纹投影三维测量方法，其特征在于，所述S2包括以下具体步骤：2. The high dynamic range fringe projection 3D measurement method based on fringe restoration according to claim 1, wherein S2 comprises the following specific steps: S21、对图像中的每个点，根据N幅相移图的饱和情况将其分为可靠区域、浅饱和区域和深饱和区域，如果拍摄的N幅相移图在某个点的值有三幅图及以上的值都小于255，那么这个点为可靠区域，其余为不可靠区域，在不可靠区域中假定Aa为实际的A参数，那么当Aa＜255时该点为浅饱和区域，当Aa≥255时该点为深饱和区域，S21. For each point in the image, divide it into a reliable area, a shallow saturation area, and a deep saturation area according to the saturation of the N phase-shift images. If the values of three or more of the N phase-shift images at a certain point are less than 255, then this point is a reliable area, and the rest are unreliable areas. In the unreliable area, assuming that Aa is the actual A parameter, then when Aa < 255, this point is a shallow saturation area, and when Aa ≥ 255, this point is a deep saturation area. S22、可靠区域的A参数直接求解，浅饱和区域和深饱和区域的A参数无法直接求解，可靠区域的A参数求解公式如下所述：S22. The A parameter of the reliable area is solved directly. The A parameter of the shallow saturation area and the deep saturation area cannot be solved directly. The A parameter solution formula of the reliable area is as follows: 根据欧拉公式eix＝cosx+isinx，In(x,y)写为：According to Euler's formula eix = cosx + isinx, In (x, y) can be written as: 条纹下标为n1,n2,...,nk的条纹没有饱和，联立(x,y)位置上这些没有饱和条纹的方程：The fringes with subscripts n 1 , n 2 , ..., n k are not saturated. The equations for these unsaturated fringes at (x, y) are combined: 那么A，B参数求解公式为：Then the formula for solving the A and B parameters is: 其中，real函数表示对复数取实部。The real function represents the real part of a complex number. 3.根据权利要求1所述的基于条纹修复的高动态范围条纹投影三维测量方法，其特征在于，所述S5包括以下具体步骤：3. The high dynamic range fringe projection 3D measurement method based on fringe restoration according to claim 1, wherein S5 comprises the following specific steps: S51、插值得到的曲面A、B和Flower中，A、B的强度较高，插值基础点少，和理想曲面误差大，Flower的插值基础点多且均匀，和理想曲面误差小，将插值得到的曲面A、B、Flower写为A′、B′、F′lower，理想曲面为A、B、Flower，由于插值函数在插值两组相同趋势的不同强度点时，能够保留梯度，所以A′，B′的比值与A，B的比值非常接近：S51. Among the interpolated surfaces A, B, and F lower , A and B have higher intensities, fewer interpolation base points, and larger errors compared to the ideal surface. F lower has more and more uniform interpolation base points and smaller errors compared to the ideal surface. The interpolated surfaces A, B, and F lower are written as A′, B′, and F′ lower , and the ideal surface is A, B, and F lower . Because the interpolation function can preserve the gradient when interpolating two sets of different intensity points with the same trend, the ratio of A′ to B′ is very close to the ratio of A to B: 此处的k(x,y)被直接定义为A’(x,y)与B’(x,y)的比值，这个比值与A(x,y)与B(x,y)的比值非常接近；Here k(x,y) is directly defined as the ratio of A’(x,y) to B’(x,y), which is very close to the ratio of A(x,y) to B(x,y); 所以和理想曲面为A，B误差很小的曲面A″，B″得以求解：Therefore, the surfaces A″ and B″ with very small errors from the ideal surfaces A and B can be solved: 4.根据权利要求1所述的基于条纹修复的高动态范围条纹投影三维测量方法，其特征在于，所述S6包括以下具体步骤：4. The high dynamic range fringe projection 3D measurement method based on fringe restoration according to claim 1, wherein S6 comprises the following specific steps: S61、N步相移中当某个图像饱和时，饱和区域的条纹修复值的修复公式如下：S61, when an image is saturated in N-step phase shift, the fringe repair value of the saturated area The repair formula is as follows: N为偶数时：When N is an even number: N为奇数时：When N is an odd number: S62、饱和相移图像使用上面修复公式修复后，如果还存在饱和的位置，这些位置以全局的非饱和条纹值和修复的条纹值为基础，用CSI插值方法进行插值补全。S62. After the saturated phase-shifted image is repaired using the above repair formula, if there are still saturated positions, these positions are interpolated and completed using the CSI interpolation method based on the global unsaturated fringe values and the repaired fringe values. 5.根据权利要求1所述的基于条纹修复的高动态范围条纹投影三维测量方法，其特征在于，所述S7包括以下具体步骤：5. The high dynamic range fringe projection 3D measurement method based on fringe restoration according to claim 1, wherein S7 comprises the following specific steps: S71、通过修复的N幅条纹图解得包裹相位：S71. Obtain the wrapped phase by reconstructing the N restored fringe patterns: 通过上式获得的相位是包裹相位，要获得高度信息需要使用展开相位，绝对相位法将包裹相位展开。The phase obtained by the above formula is the wrapped phase. To obtain height information, the unwrapped phase needs to be used. The absolute phase method unwraps the wrapped phase. 6.根据权利要求1所述的基于条纹修复的高动态范围条纹投影三维测量方法，其特征在于，所述S8包括以下具体步骤：6. The high dynamic range fringe projection 3D measurement method based on fringe restoration according to claim 1, wherein S8 comprises the following specific steps: S81、投影多幅格雷码条纹图案到高反射率物体表面，用CCD获取格雷码条纹图，前几幅图用来计算级次，最后一幅图用来对级次进行矫正，得到条纹的级次K；S81, projecting multiple Gray code fringe patterns onto the surface of a high reflectivity object, and using a CCD to obtain Gray code fringe patterns. The first few patterns are used to calculate the order, and the last pattern is used to correct the order to obtain the order K of the fringe. S82、使用级次K对包裹相位进行展开，展开公式如下：S82. Use the order K to unfold the wrapped phase. The unfolding formula is as follows: 最后求得的Φ(x,y)即是展开相位。The final Φ(x,y) obtained is the unfolded phase.
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