CN113029039A - Three-dimensional measurement absolute phase correction method based on color coding - Google Patents

Three-dimensional measurement absolute phase correction method based on color coding Download PDF

Info

Publication number
CN113029039A
CN113029039A CN202110114105.XA CN202110114105A CN113029039A CN 113029039 A CN113029039 A CN 113029039A CN 202110114105 A CN202110114105 A CN 202110114105A CN 113029039 A CN113029039 A CN 113029039A
Authority
CN
China
Prior art keywords
phase
stripes
stripe
color
coding
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CN202110114105.XA
Other languages
Chinese (zh)
Other versions
CN113029039B (en
Inventor
李洪儒
崔磊
袁寒
包忠毅
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Sichuan University
Original Assignee
Sichuan University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Sichuan University filed Critical Sichuan University
Priority to CN202110114105.XA priority Critical patent/CN113029039B/en
Publication of CN113029039A publication Critical patent/CN113029039A/en
Application granted granted Critical
Publication of CN113029039B publication Critical patent/CN113029039B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • 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
    • 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
    • G01B11/2504—Calibration devices
    • 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
    • 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
    • G01B11/2509—Color coding

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Vision & Pattern Recognition (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Length Measuring Devices By Optical Means (AREA)

Abstract

The invention provides a three-dimensional measurement absolute phase correction method based on color coding. The color coding-based three-dimensional measurement absolute phase correction method comprises the following steps: s1 encoding the color stripes; s2, projecting the color stripes on an object to be measured, and acquiring the color deformation stripes by the CCD; s3 extracting two groups of phase information from the color deformed stripes; s4 phase corrects the main phase with the additional phase to obtain accurate phase information. The three-dimensional measurement absolute phase correction method based on color coding provided by the invention has the advantages that the projector projects the coded stripes onto an object, then the camera collects the captured color deformed stripes, two groups of coded phase information can be extracted from the color deformed stripes, the phase information is subjected to wrapped phase calculation and unwrapping to obtain two groups of unwrapped phases, finally the second group of unwrapped phases is used for carrying out phase correction on the first group to obtain an accurate phase, and finally the three-dimensional measurement precision is improved.

Description

Three-dimensional measurement absolute phase correction method based on color coding
Technical Field
The invention relates to the technical field of image processing, in particular to a three-dimensional measurement absolute phase correction method based on color coding.
Background
Three-dimensional measurement is very important in many fields, such as surveying and mapping engineering, building and historic site measurement, and in the field of three-dimensional measurement, fast acquisition of high-precision data of an object is always an important technical difficulty.
With the continuous expansion of modern industrialization, a non-contact optical three-dimensional measurement technology is widely applied to various fields such as quality detection, reverse engineering, human body detection, cultural relic protection and the like, in the optical three-dimensional measurement technology, a fringe projection technology is one of the most widely applied three-dimensional measurement technologies at present due to the characteristics of non-contact, low cost, high resolution and the like, and for the fringe projection technology, methods for extracting envelope phases such as Fourier transform, wavelet transform, phase shift algorithm and the like exist.
However, for a measurement object with a complex shape, the fourier transform and wavelet transform techniques require complex calculation, and cannot accurately extract the wrapped phase, and the phase shift algorithm is widely applied to the measurement of the complex-shaped object due to its advantages of high speed, high precision and the like, and the absolute phase is encoded on the basis of the phase shift algorithm and used for retrieval of phase unwrapping, so that the wrapped phase can be accurately and quickly unwrapped.
The absolute phase method is widely used for phase unpacking of three-dimensional measurement due to good measurement accuracy and robustness, but due to the influences of nonlinearity of CCD (charge coupled device) acquired images, environmental noise and the like, error codes are easy to occur at the edge of an absolute phase step, and a good result can be obtained only by performing phase correction on the absolute phase step.
Therefore, it is necessary to provide a color-coding-based three-dimensional measurement absolute phase correction method to solve the above technical problems.
Disclosure of Invention
The invention provides a three-dimensional measurement absolute phase correction method based on color coding, which solves the problem that error codes are easy to appear on absolute phase step edges.
In order to solve the technical problem, the three-dimensional measurement absolute phase correction method based on color coding provided by the invention comprises the following steps:
s1 encoding the color stripes;
s2, projecting the color stripes on an object to be measured, and acquiring the color deformation stripes by the CCD;
s3 extracting two groups of phase information from the color deformed stripes;
s4 phase corrects the main phase with the additional phase to obtain accurate phase information.
Preferably, when the color stripes are encoded in step S1, the color encoded stripes include stripes I and stripes II, and the stripes I are composed of sine stripes and corresponding ladder stripes;
the formula of the sine stripe coding is as follows:
Ik(x,y)＝A(x,y)+B(x,y)cos(φI+δk) (1)，
a (x, y) is the average intensity, B (x, y) is the intensity modulation, phiIFor sinusoidal coding of phase, deltakTo shift the phase, wherein
φI＝2πyf0 (2)，
Figure BDA0002919999630000021
f0For fringe frequency, k is the number of phase shift steps.
Preferably, the sinusoidal fringe coding phase phi in the sinusoidal fringe coding formulaIPhase encoding by replacement with echelle encoding
Figure BDA0002919999630000022
A code stripe of a ladder stripe can be obtained, wherein the ladder stripe phase code is:
Figure BDA0002919999630000023
wherein M is the step number of each period of the stripe, and P is the interval of the stripe;
the combination of the sinusoidal and stepped stripes is called stripe I, and stripe II is shifted relative to stripe IMovable part
Figure BDA0002919999630000024
Namely, the phase pi is moved, and the stripe II also comprises a sine stripe and a corresponding step stripe;
sinusoidal fringe encoding phase phi of fringe IIIIComprises the following steps:
φII＝2π(y+P/2)f0 (5)，
echelle code phase of stripe II
Figure BDA0002919999630000025
Comprises the following steps:
Figure BDA0002919999630000031
in the same way, let the sinusoidal fringe code phase phi of fringe IIIIAnd echelle code phase
Figure BDA0002919999630000032
Replacing phi in sinusoidal stripe encoding formulaIA sinusoidal stripe and a corresponding step stripe of stripe II can be obtained.
Preferably, the coding stripe I is placed in an R channel of a color coding stripe, and the coding stripe II is placed in a B channel of the color coding stripe to form the color coding stripe.
Preferably, when the phase information is extracted in step S3, the R and B channel data of the collected color deformed stripes are extracted to obtain two sets of gray stripes.
Preferably, the fringe I is then substituted into the wrapped phase calculation formula to obtain sinusoidal and stepped wrapped phases φ'IAnd
Figure BDA0002919999630000033
and respectively calculating wrapping phases of the two groups of gray stripes, wherein the wrapping phases are calculated according to the formula:
Figure BDA0002919999630000034
Ikand (3) for the sine stripes acquired by the camera, the phase shift step number of the sine stripes is N, and the stripe II is brought into a wrapping phase calculation formula to obtain wrapping phases phi 'of the sine and the step'IIAnd
Figure BDA0002919999630000035
preferably, the wrapped phases are then unwrapped using absolute phase step encoding to obtain two sets of unwrapped phases ΦIAnd phiIIThe phase unwrapping process is specifically as follows, and the fringe order k and r are calculated:
Figure BDA0002919999630000036
Figure BDA0002919999630000037
Figure BDA0002919999630000038
Figure BDA0002919999630000039
wherein r (i) is a sub-region code word of k (i) corresponding to the ith pixel of each row, k (i) is a coding order corresponding to the ith pixel of each row, and then, according to k and r, unwrapping the wrapping phase:
Figure BDA0002919999630000041
Figure BDA0002919999630000042
preference is given toIn step S4, when the additional phase is used to correct the phase of the main phase, Φ is first correctedI、ΦIISelf-contrast the two to remove the reduced phase error code to obtain the first corrected phase phi'I、Φ′II：
Figure BDA0002919999630000043
Figure BDA0002919999630000044
Preferably, the phase phi 'of the first correction'I、Φ′IIAfter obtaining, according to the phase phi 'of the first correction'I、Φ′IICalculating step error code value delta k, and judging phi 'by comparing the two values'IThe two are subtracted at the error code position and divided by 2 pi to be rounded to obtain phi'IStep error difference value Δ k:
Figure BDA0002919999630000045
preferably, phi 'is used after the step error code difference value delta k is obtained'ISubtracting delta k 2 pi to perform secondary phase correction to obtain correct phase phi ″I：
Φ″I(x,y)＝Φ′I(x,y)-Δk×2π (17)。
Compared with the related technology, the color coding-based three-dimensional measurement absolute phase correction method provided by the invention has the following beneficial effects:
the invention provides a three-dimensional measurement absolute phase correction method based on color coding.A video camera and a projector are connected to a computer, the computer controls a system in real time and acquires data, the projector projects coded stripes onto an object, then the camera collects the captured color deformed stripes, two groups of coded phase information can be extracted from the color deformed stripes, the phase information is subjected to calculation and unwrapping of wrapped phases to obtain two groups of unwrapped phases, and finally the second group of unwrapped phases is used for carrying out phase correction on the first group to obtain an accurate phase, so that the measurement accuracy is finally improved.
Drawings
FIG. 1 is a flow chart and an apparatus diagram of color-coded absolute phase correction of a three-dimensional measurement absolute phase correction method based on color coding according to the present invention;
FIG. 2 is a flowchart illustrating the operation of the method for correcting absolute phase of three-dimensional measurement based on color coding according to the present invention;
FIG. 3 is a color stripe code pattern provided by the present invention;
FIG. 4 is an exploded view of a color deformed stripe according to the present invention;
FIG. 5 is a pre-correction planar measurement image provided by the present invention;
FIG. 6 is a corrected planar measurement image provided by the present invention;
FIG. 7 is a pre-correction object measurement image provided by the present invention;
FIG. 8 is a corrected object measurement image provided by the present invention;
fig. 9 is a supporting device used in the object detection of the color-coding-based three-dimensional measurement absolute phase correction method provided by the invention.
Reference numbers in the figures: 1. containing box, 2, telescopic link, 3, lift apron, 4, supporting cover, 41, connection slide opening, 5, elevator motor, 51, lifting screw, 52, lift slide, 53, linkage clamp plate, 6, supporting disk, 7, light screen, 71, regulation hole, 8, locking screw.
Detailed Description
The invention is further described with reference to the following figures and embodiments.
Please refer to fig. 1, fig. 2, fig. 3, fig. 4, fig. 5, fig. 6, fig. 7, fig. 8 and fig. 9 in combination, wherein fig. 1 is a flowchart and an apparatus of color-coded absolute phase correction of a color-coded three-dimensional measured absolute phase correction method according to the present invention; FIG. 2 is a flowchart illustrating the operation of the method for correcting absolute phase of three-dimensional measurement based on color coding according to the present invention; FIG. 3 is a color stripe code pattern provided by the present invention; FIG. 4 is an exploded view of a color deformed stripe according to the present invention; FIG. 5 is a pre-correction planar measurement image provided by the present invention; FIG. 6 is a corrected planar measurement image provided by the present invention; FIG. 7 is a pre-correction object measurement image provided by the present invention; FIG. 8 is a corrected object measurement image provided by the present invention; fig. 9 is a supporting device used in the object detection of the color-coding-based three-dimensional measurement absolute phase correction method provided by the invention.
A three-dimensional measurement absolute phase correction method based on color coding comprises the following steps: s1 encoding the color stripes;
s2, projecting the color stripes on an object to be measured, and acquiring the color deformation stripes by the CCD;
s3 extracting two groups of phase information from the color deformed stripes;
s4 phase corrects the main phase with the additional phase to obtain accurate phase information.
In the fringe projection technology, the precondition for acquiring the three-dimensional information is to acquire phase information, perform phase height mapping on the phase information to acquire corresponding three-dimensional information, and whether the phase information is accurate is directly related to the accuracy of three-dimensional measurement.
The connection diagram of the process and the device is shown in figure 1, a video camera and a projector are connected to a computer, the computer controls a system in real time and obtains data, the projector projects the coded stripes onto an object, then the camera collects the captured color deformed stripes, two groups of encoded phase information can be extracted from the color deformed stripes, the phase information is subjected to phase wrapping calculation and unwrapping, two groups of unwrapped phases are obtained, finally the second group of unwrapped phases is used for carrying out phase correction on the first group, the accurate phase can be obtained, and the measurement accuracy is finally improved.
When the color stripes are encoded in the step S1, the color encoded stripes include stripes I and stripes II, and the stripes I are composed of sine stripes and corresponding ladder stripes;
the formula of the sine stripe coding is as follows:
Ik(x,y)＝A(x,y)+B(x,y)cos(φI+δk) (1)，
a (x, y) is the average intensity, B (x, y) is the intensity modulation, phiIFor sinusoidal coding of phase, deltakTo shift the phase, wherein
φI＝2πyf0 (2)，
Figure BDA0002919999630000061
f0For fringe frequency, k is the number of phase shift steps.
The sinusoidal fringe coding phase phi in the sinusoidal fringe coding formulaIPhase encoding by replacement with echelle encoding
Figure BDA0002919999630000062
A code stripe of a ladder stripe can be obtained, wherein the ladder stripe phase code is:
Figure BDA0002919999630000063
wherein M is the step number of each period of the stripe, and P is the interval of the stripe;
the combination of the sinusoidal and stepped stripes is called stripe I, and stripe II moves relative to stripe I
Figure BDA0002919999630000064
Namely, the phase pi is moved, and the stripe II also comprises a sine stripe and a corresponding step stripe;
sinusoidal fringe encoding phase phi of fringe IIIIComprises the following steps:
φII＝2π(y+P/2)f0 (5)，
step of stripe IILadder stripe code phase
Figure BDA0002919999630000071
Comprises the following steps:
Figure BDA0002919999630000072
in the same way, let the sinusoidal fringe code phase phi of fringe IIIIAnd echelle code phase
Figure BDA0002919999630000073
Replacing phi in sinusoidal stripe encoding formulaIA sinusoidal stripe and a corresponding step stripe of stripe II can be obtained.
The coding stripe I is placed in an R channel of the color coding stripe, and the coding stripe II is placed in a B channel of the color coding stripe to form the color coding stripe.
As shown in fig. 3: the G channel has no coding stripes, otherwise, color crosstalk can be generated, and the phase shift step number k is 3 in the figure;
wherein:
in FIG. 3, the (a) - (c) code phases are phiΙ；
In FIG. 3, the (d) - (e) code phases are
Figure RE-GDA0003062623510000076
In FIG. 3, (g) - (i) encode phases areII；
In FIG. 3 the (j) - (l) code phases are
Figure RE-GDA0003062623510000077
When the phase information is extracted in step S3, the R and B channel data of the collected color deformed stripes are extracted to obtain two sets of gray stripes.
As shown in fig. 3: for example, if the image matrix of the color image is m × n × 3, the first m × n array of the matrix is an R-channel grayscale map of the color image, and the third m × n array is a B-channel grayscale map of the color image.
And then the stripe I is substituted into a wrapping phase calculation formula to obtain wrapping phases phi 'of sine and step'IAnd
Figure BDA0002919999630000076
and respectively calculating wrapping phases of the two groups of gray stripes, wherein the wrapping phases are calculated according to the formula:
Figure BDA0002919999630000077
Ikand (3) for the sine stripes acquired by the camera, the phase shift step number of the sine stripes is N, and the stripe II is brought into a wrapping phase calculation formula to obtain wrapping phases phi 'of the sine and the step'IIAnd
Figure BDA0002919999630000078
then, the absolute phase step coding is applied to expand the wrapping phase to obtain two groups of expanded phases phiIAnd phiIIThe phase unwrapping process is specifically as follows, and the fringe order k and r are calculated:
Figure BDA0002919999630000081
Figure BDA0002919999630000082
Figure BDA0002919999630000083
Figure BDA0002919999630000084
wherein r (i) is a sub-region code word of k (i) corresponding to the ith pixel of each row, k (i) is a coding order corresponding to the ith pixel of each row, and then, according to k and r, unwrapping the wrapping phase:
Figure BDA0002919999630000085
Figure BDA0002919999630000086
in the step S4, when the additional phase is used to correct the phase of the main phase, Φ is first correctedI、ΦIISelf-contrast the two to remove the reduced phase error code to obtain the first corrected phase phi'I、Φ′II：
Figure BDA0002919999630000087
Figure BDA0002919999630000088
Phase phi 'of the first correction'I、Φ′IIAfter obtaining, according to the phase phi 'of the first correction'I、Φ′IICalculating step error code value delta k, and judging phi 'by comparing the two values'IThe two are subtracted at the error code position and divided by 2 pi to be rounded to obtain phi'IStep error difference value Δ k:
Figure BDA0002919999630000089
phi 'is used after the step error code difference value delta k is obtained'ISubtracting delta k 2 pi to perform secondary phase correction to obtain correct phase phi ″I：
Φ″I(x,y)＝Φ′I(x,y)-Δk×2π (17)。
Compared with the related technology, the color coding-based three-dimensional measurement absolute phase correction method provided by the invention has the following beneficial effects:
the camera and the projector are connected to a computer, the computer controls the system in real time and obtains data, the projector projects the coded stripes onto an object, then the camera collects the captured color deformed stripes, two groups of encoded phase information can be extracted from the color deformed stripes, the phase information is subjected to phase wrapping calculation and unwrapping to obtain two groups of unwrapped phases, finally the second group of unwrapped phases is used for carrying out phase correction on the first group to obtain an accurate phase, and finally the measurement precision is improved.
According to the steps a-d, the phase of the object to be measured can be measured, fig. 4 shows the phase of the front plane to be corrected, fig. 5 shows the phase of the rear plane to be corrected by the method of the present invention, and it is found that the error code of fig. 4 is obvious, and the error code is in the shape of a stripe sharp spike, which is caused by the fringe edge level error when the phase is unfolded by the absolute phase method, fig. 5 shows that the error code is completely removed by the phase correction of the method of the present invention, the white plane is measured, fig. 6 shows the phase of the front plane to be corrected, fig. 7 shows the phase of the rear plane to be corrected by the method of the present.
A supporting device of an object is required to be used before the object is detected based on a color coding three-dimensional measurement absolute phase correction method, the supporting device comprises a storage box 1, a telescopic rod 2 is fixedly connected to the bottom of the inner wall of the storage box 1, a lifting cover plate 3 is fixedly connected to the output end of the telescopic rod 2, the surface of the lifting cover plate 3 is matched with the surface of the storage box 1, a supporting cover 4 is fixedly connected to the bottom of the lifting cover plate 3, a connecting sliding hole 41 is formed in the surface of the supporting cover 4, the inside of the connecting sliding hole 41 is communicated with the inside of the supporting cover 4, a lifting motor 5 is fixedly connected to the top of the lifting cover plate 3, a lifting screw 51 is fixedly connected to the output end of the lifting motor 5, the bottom end of the lifting screw 51 penetrates through the surface of the lifting cover plate 3 and extends to the lower part of the lifting cover plate 3, the surface of the lifting screw 51 is rotatably connected with the surface of the lifting cover plate 3, the surface of the lifting screw 51 is in threaded connection with a lifting sliding plate 52, one side of the lifting sliding plate 52 passes through the inside of the connecting sliding hole 41 and extends to the outside of the supporting cover 4, the surface of the lifting sliding plate 52 is in sliding connection with the inner surface of the connecting sliding hole 41, one side of the lifting sliding plate 52 is fixedly connected with a linkage pressing plate 53, the surface of the linkage pressing plate 53 is in an annular structure, the inner surface of the linkage pressing plate 53 is in sliding connection with the outer surface of the supporting cover 4, the outer surface of the supporting cover 4 is fixedly connected with a supporting plate 6, the surface of the supporting plate 6 and the surface of the linkage pressing plate 53 are distributed in parallel, the outer surface of the supporting cover 4 is rotatably connected with a light shielding plate 7, and the light shielding, the inner surface of the adjusting hole 71 is in sliding connection with the surface of the supporting disk 6, the surface of the light shielding plate 7 is in threaded connection with a locking screw 8, and the surface of the locking screw 8 is matched with the surface of the supporting disk 6.
The light shading plate 7 adopts the existing light shading plate, so that after an object is arranged on the surface of the supporting plate 6, the influence of the light reflection of the light shading plate 7 on lighting is avoided, the stability of illumination reflection during object image acquisition is ensured, the interference of external light reflection is reduced, and the stability of object image acquisition is improved;
the light screen 7 is convenient to rotate and adjust after the locking screw 8 is loosened, so that the position of the light screen 7 can be conveniently adjusted adaptively according to the placing direction of an object, and the adjusted light screen 7 is convenient to position after the locking screw 8 is screwed tightly, so that the stability of the light screen 7 in use is guaranteed;
the shading plate 7, the supporting plate 6 and the linkage pressing plate 53 are made of the same material.
The lifting motor 5 conveniently drives the lifting screw 51 to rotate and adjust, the lifting screw 51 conveniently drives the lifting sliding plate 52 to synchronously lift and adjust when rotating, and the lifting sliding plate 52 conveniently drives the linkage sliding plate 53 to synchronously move up and down and adjust when lifting and adjusting;
when the lifting screw 51 rotates forwards, the lifting screw 51 drives the lifting sliding plate 52 to move upwards, the linkage pressing plate 53 is driven to move upwards when the lifting sliding plate 52 moves upwards, and an object is conveniently arranged above the supporting plate 6 after the linkage pressing plate 53 moves upwards;
when the lifting screw 51 rotates reversely, the lifting screw 51 drives the lifting sliding plate 52 to move downwards, the lifting sliding plate 52 moves downwards and drives the linkage pressing plate 53 to move downwards, and the linkage pressing plate 53 stably clamps and fixes the object above the supporting plate 6 when moving downwards, so that the stability of collecting the object is guaranteed.
The above description is only an embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes, which are made by using the contents of the present specification and the accompanying drawings, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.

Claims (10)

1. A three-dimensional measurement absolute phase correction method based on color coding is characterized by comprising the following steps:
s1 encoding the color stripes;
s2, projecting the color stripes on an object to be measured, and acquiring the color deformation stripes by the CCD;
s3 extracting two groups of phase information from the color deformed stripes;
s4 phase corrects the main phase with the additional phase to obtain accurate phase information.
2. The method according to claim 1, wherein when the color stripes are encoded in step S1, the color encoded stripes comprise stripes i and stripes i, and the stripes i comprise sinusoidal stripes and corresponding staircase stripes;
the formula of the sine stripe coding is as follows:
Ik(x,y)＝A(x,y)+B(x,y)cos(φΙ+δk) (1)，
a (x, y) is the average intensity, B (x, y) is the intensity modulation, phiΙFor sinusoidal coding of phase, deltakTo shift the phase, wherein
φΙ＝2πyf0 (2)，
Figure FDA0002919999620000011
f0For fringe frequency, k is the number of phase shift steps.
3. The method of claim 2, wherein the sinusoidal fringe coding formula has a sinusoidal fringe coding phase phiΙPhase encoding by replacement with echelle encoding
Figure FDA0002919999620000012
A code stripe of a ladder stripe can be obtained, wherein the ladder stripe phase code is:
Figure FDA0002919999620000013
wherein M is the step number of each period of the stripe, and P is the interval of the stripe;
the combination of the sinusoidal and the step stripes is called stripe I, which moves relative to stripe I
Figure FDA0002919999620000014
Namely, the phase position pi is shifted, and the stripe I also comprises a sine stripe and a corresponding step stripe;
the sinusoidal fringe coding phase phi of the fringe IΙΙComprises the following steps:
φΙΙ＝2π(y+P/2)f0 (5)，
fringe I step fringe code phase
Figure FDA0002919999620000021
Comprises the following steps:
Figure FDA0002919999620000022
in a similar way, the phase phi of the sinusoidal stripe code for the stripe I is setΙΙAnd echelle code phase
Figure FDA0002919999620000023
Replacing phi in sinusoidal stripe encoding formulaΙThe sine stripe of the stripe I and the corresponding step stripe can be obtained.
4. The method according to claim 3, wherein the coding fringe I is placed in the R channel of the color coding fringe, and the coding fringe I is placed in the B channel of the color coding fringe to form the color coding fringe.
5. The method for correcting absolute phase of three-dimensional measurement based on color coding according to claim 4, wherein the R and B channel data of the collected color deformed stripes are extracted to obtain two sets of gray stripes when extracting the phase information in step S3.
6. The color-coding-based absolute phase correction method for three-dimensional measurement according to claim 5, wherein the fringe I is then substituted into the wrapping phase calculation formula to obtain the wrapping phases phi 'of sine and step'IAnd
Figure FDA0002919999620000024
and respectively calculating wrapping phases of the two groups of gray stripes, wherein the wrapping phases are calculated according to the formula:
Figure FDA0002919999620000025
Ikand (3) for the sine stripes acquired by the camera, the phase shift step number of the sine stripes is N, and the stripe II is brought into a wrapping phase calculation formula to obtain wrapping phases phi 'of the sine and the step'IIAnd
Figure FDA0002919999620000026
7. the method of claim 6, wherein the wrapped phase is unwrapped using absolute phase ladder coding to obtain two sets of unwrapped phases ΦIAnd phiIIThe phase unwrapping process is specifically as follows, and the fringe order k and r are calculated:
Figure FDA0002919999620000027
Figure FDA0002919999620000028
Figure FDA0002919999620000031
Figure FDA0002919999620000032
wherein r (i) is a sub-region code word of k (i) corresponding to the ith pixel of each row, k (i) is a coding order corresponding to the ith pixel of each row, and then, according to k and r, unwrapping the wrapping phase:
Figure FDA0002919999620000033
Figure FDA0002919999620000034
8. the method of claim 7, wherein the phi is first determined when the additional phase is used to correct the phase of the main phase in step S4I、ΦIISelf-contrast the two to remove the reduced phase error code to obtain the first corrected phase phi'I、Φ′ΙΙ：
Figure FDA0002919999620000035
Figure FDA0002919999620000036
9. The color-coding-based three-dimensional measurement absolute phase correction method according to claim 8, wherein the phase Φ 'of the first correction'Ι、Φ′ΙΙAfter obtaining, according to the phase phi 'of the first correction'Ι、Φ′ΙICalculating step error code value delta k, and judging phi 'by comparing the two values'IThe two are subtracted at the error code position and divided by 2 pi to be rounded to obtain phi'IStep error difference Δ k:
Figure FDA0002919999620000037
10. the method of claim 9, wherein phi 'is used again after the step error code difference Δ k is obtained'ISubtracting delta k 2 pi to perform the second phase correction to obtain the correct phase phi ″I：
Φ″Ι(x,y)＝Φ′Ι(x,y)-△k×2π (17)。
CN202110114105.XA 2021-01-27 2021-01-27 Three-dimensional measurement absolute phase correction method based on color coding Active CN113029039B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202110114105.XA CN113029039B (en) 2021-01-27 2021-01-27 Three-dimensional measurement absolute phase correction method based on color coding

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202110114105.XA CN113029039B (en) 2021-01-27 2021-01-27 Three-dimensional measurement absolute phase correction method based on color coding

Publications (2)

Publication Number Publication Date
CN113029039A true CN113029039A (en) 2021-06-25
CN113029039B CN113029039B (en) 2022-04-12

Family

ID=76459432

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202110114105.XA Active CN113029039B (en) 2021-01-27 2021-01-27 Three-dimensional measurement absolute phase correction method based on color coding

Country Status (1)

Country Link
CN (1) CN113029039B (en)

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008157797A (en) * 2006-12-25 2008-07-10 Matsushita Electric Works Ltd Three-dimensional measuring method and three-dimensional shape measuring device using it
CN101813461A (en) * 2010-04-07 2010-08-25 河北工业大学 Absolute phase measurement method based on composite color fringe projection
KR101700938B1 (en) * 2015-12-24 2017-02-01 인천대학교 산학협력단 Method for generating patterns and obtaining absolute phase for 3-d shape measurement
CN106840036A (en) * 2016-12-30 2017-06-13 江苏四点灵机器人有限公司 A kind of diadactic structure light optimization method suitable for fast three-dimensional appearance measuring
CN108955574A (en) * 2018-07-09 2018-12-07 广东工业大学 A kind of method for three-dimensional measurement and system
CN109186476A (en) * 2018-10-26 2019-01-11 广东工业大学 A kind of color structured light method for three-dimensional measurement, device, equipment and storage medium
CN109297435A (en) * 2018-10-24 2019-02-01 重庆大学 A kind of reversed colorful number grating encoding method for offsetting nonlinearity erron
CN111207694A (en) * 2020-01-13 2020-05-29 南昌航空大学 Three-dimensional measurement method combining double-step phase shift method with phase coding

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008157797A (en) * 2006-12-25 2008-07-10 Matsushita Electric Works Ltd Three-dimensional measuring method and three-dimensional shape measuring device using it
CN101813461A (en) * 2010-04-07 2010-08-25 河北工业大学 Absolute phase measurement method based on composite color fringe projection
KR101700938B1 (en) * 2015-12-24 2017-02-01 인천대학교 산학협력단 Method for generating patterns and obtaining absolute phase for 3-d shape measurement
CN106840036A (en) * 2016-12-30 2017-06-13 江苏四点灵机器人有限公司 A kind of diadactic structure light optimization method suitable for fast three-dimensional appearance measuring
CN108955574A (en) * 2018-07-09 2018-12-07 广东工业大学 A kind of method for three-dimensional measurement and system
CN109297435A (en) * 2018-10-24 2019-02-01 重庆大学 A kind of reversed colorful number grating encoding method for offsetting nonlinearity erron
CN109186476A (en) * 2018-10-26 2019-01-11 广东工业大学 A kind of color structured light method for three-dimensional measurement, device, equipment and storage medium
CN111207694A (en) * 2020-01-13 2020-05-29 南昌航空大学 Three-dimensional measurement method combining double-step phase shift method with phase coding

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
周灿林等: "改进的阶梯相位去包裹算法研究", 《光电子.激光》 *

Also Published As

Publication number Publication date
CN113029039B (en) 2022-04-12

Similar Documents

Publication Publication Date Title
CN112097689B (en) Calibration method of 3D structured light system
Chen et al. Accurate calibration for a camera–projector measurement system based on structured light projection
CN101986098B (en) Tricolor projection-based Fourier transform three-dimensional measuring method
CN107036556B (en) Structured light three-dimensional measurement method based on segmented quantization phase coding
CN110849290B (en) Three-dimensional measurement method for segmented quantization coding intensity based on morphological operation
CN107607060A (en) A kind of phase error compensation method in the measurement applied to grating tripleplane
US20100188400A1 (en) Method for simultaneous hue phase-shifting and system for 3-d surface profilometry using the same
CN112880589B (en) Optical three-dimensional measurement method based on double-frequency phase coding
Dufour et al. Integrated digital image correlation for the evaluation and correction of optical distortions
CN109974625B (en) Color object structured light three-dimensional measurement method based on hue optimization gray scale
CN110500970B (en) Multi-frequency structured light three-dimensional measurement method
Koninckx et al. Scene-adapted structured light
CN107014313B (en) Method and system for weighted least square phase unwrapping based on S-transform ridge value
Wang et al. A 3D shape measurement method based on novel segmented quantization phase coding
Xiaoling et al. Calibration of a fringe projection profilometry system using virtual phase calibrating model planes
CN114972538A (en) Thickness measuring device and method of flattened ultrathin heat pipe based on binocular structured light
CN113029039B (en) Three-dimensional measurement absolute phase correction method based on color coding
CN112611341B (en) Color response model-based rapid three-dimensional measurement method for color object
CN114322843A (en) Digital fringe projection-based three-dimensional measurement fringe principal value phase extraction method
Su et al. Complex object profilometry and its application for dentistry
CN113124779A (en) Rapid bidirectional structured light decoding method
CN112419390A (en) Method and system for measuring height of human body
CN113310431B (en) Four-frame rapid three-dimensional measurement method based on phase coding
CN112361992B (en) Grating projection three-dimensional measurement method and device
CN117387523A (en) Three-dimensional measurement method and device based on structured light, electronic equipment and storage medium

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant