CN107525475B - A kind of object height measurement method - Google Patents

A kind of object height measurement method Download PDF

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Publication number
CN107525475B
CN107525475B CN201710760211.9A CN201710760211A CN107525475B CN 107525475 B CN107525475 B CN 107525475B CN 201710760211 A CN201710760211 A CN 201710760211A CN 107525475 B CN107525475 B CN 107525475B
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point
reference point
shooting
height
measurement
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CN107525475A (en
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李兰满
郑后俊
王煊
韦双慧
范开桂
钱江潮
朱首贤
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Hohai University HHU
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    • 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
    • G01B11/02—Measuring arrangements characterised by the use of optical techniques for measuring length, width or thickness
    • G01B11/06—Measuring arrangements characterised by the use of optical techniques for measuring length, width or thickness for measuring thickness ; e.g. of sheet material
    • G01B11/0608—Height gauges
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
    • G01C11/00—Photogrammetry or videogrammetry, e.g. stereogrammetry; Photographic surveying

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Multimedia (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Remote Sensing (AREA)
  • Length Measuring Devices By Optical Means (AREA)

Abstract

The invention discloses a kind of object height measurement methods, comprising: photograph to object, measurement object shooting height, shooting inclination angle, in photography photo object pixels tall, the vertical pixel distance of object bottom to photo lower edge；It photographs to reference point, 2 reference points are placed on the ground, it is photographed using identical shooting inclination angle to reference point, measures the pixel distance of reference point shooting height, each reference point to camera lens center in the distance of the subpoint on ground, photography photo between 2 reference points；Utilize reference point measurement data, computational photogrammetry parameter；Using object measurement data and photogrammetric parameter, object actual height is calculated；Measuring device of the present invention is simple, easy to carry, of less demanding to operating environment, applied widely；There is apparent advantage for dynamic object object measurement.

Description

A kind of object height measurement method
Technical field
The present invention relates to a kind of object height measurement methods.
Background technique
Object elevation carrection is the frequently problem in daily life, engineering and scientific research.Daily life In more common height measurement method be conventional contact measurement method, that is, utilize ruler to carry out elevation carrection.In engineering relatively often Height measurement method is that ruler amount is high, theodolite cooperation steel ruler survey is high, total station surveys high, laser ranging altitude meter and surveys height.
Height is surveyed using ruler and belongs to traditional contact measurement method, is directly measured on object using ruler.This kind The advantages of measurement method, is: it can guarantee good measurement accuracy in tape measure range ability, it is simple and quick, and it is suitable for The measurement work of precision target object.The shortcomings that this kind of method is: object measurement biggish for height is difficult；For can not The rugged protrusion of the object or body surface directly contacted is serious, and measurement difficulty is big.
Need to generally following steps be carried out with when transit survey object height: calibration survey station point first, in survey station point Upper placement theodolite, after pair warp and weft instrument slightly put down, is aimed at, essence is flat, using level between tape measuring survey station point and object away from From, also can use theodolite and levelling rod, based on subtense technique ranging from.With the angle of depression of itself and object bottom of transit survey And with the elevation angle at the top of object, to calculate the height of object by geometrical relationship, measurement accuracy is higher.But it passes through Latitude instrument quality is larger, inconvenient to carry；The ground of erection needs hard ground, and theodolite sedimentation otherwise can be caused unstable, influenced Measurement accuracy, for the specific environmental adaptabilities such as weak soil or sandy beach deficiency.Centering leveling is also needed when erection, for carry out It the case where multimetering, needs to take a significant amount of time and does homework.
It, can be direct the case where for prism can be disposed above and below object when with total station survey object height The three-dimensional coordinate of object or more is measured, to calculate object height.The case where for prism can not be disposed at the top of object, It can carry out Suspension surveying.Substantially steps are as follows for it: placing prism in object bottom, then measures itself and prism using total station The flat vertical angle away from and with target top, so as to find out object height.High advantage is surveyed using total station to be to reduce Human error, reading data and processing are more convenient.That but there are still instrument qualities is big, complicated for operation, has to setting up ground The disadvantages of high requirement.
Laser ranging altitude meter (altitude meter) be laser ranging system and vertical angle sensor are combined into one it is hand-held Instrument for quick measuring.Altitude meter has a function of automatic lock onto target object, and when use need to only pin " range " button and in visiting object lens Guarantee that red instruction photoelectricity is directed at determinand, laser beam can issue after release button from altitude meter, guarantee that user has Time enough carrys out lock onto target.The each measurement of altitude meter is all made of multiplicating measurement, when acquisition measurement enough After information, measurement result can be automatically displayed on liquid crystal board.The advantages of this method: it is light and handy portable, it is easy to operate, measure the tree height, Construction site etc. is to the fields of measurement application that required precision is not high and limited cost.The disadvantages of this method has: instrument institute The size and reflectivity of the precision and target to be measured that are capable of measuring have much relations, high for object error too dark or too bright.
Summary of the invention
It is an object of the invention to overcome deficiency in the prior art, a kind of object height measurement method is provided, is solved Object height measurement method there are the scope of applications small, complicated for operation, instruments weight is greatly to operating environment requirement in the prior art It is excessively high, be not suitable for dynamic object object measurement etc. technical problems.
In order to solve the above technical problems, the technical scheme adopted by the invention is that: a kind of object height measurement method, packet Include following steps:
(1) to the photography of object and measurement: being photographed using camera to object；Measurement shooting height, shooting are inclined Oblique angle；The pixels tall of object, the vertical pixel distance of object bottom to photo lower edge on metric photography photo；
(2) to the photography of reference point and measurement: placing 2 reference points on ground, make 2 reference points and camera with always It on line, is photographed using shooting inclination angle identical with step (1) to reference point, measures shooting height, each reference point to phase Distance of the machine optical center in the subpoint on ground；Pixel distance on metric photography photo between 2 reference points；
(3) photogrammetric parameter calculates: utilizing the reference point measurement data of step (2), the photography designed by this patent Measurement parameter calculation method calculates the corresponding photogrammetric parameter in inclination angle in step (2), and calculation formula is as follows:
Wherein: PO', O'A' are photogrammetric parameter；PO' indicate P and O' between linear distance, O' be photographic plane and The intersection point of PO；PO be reference point shooting straight line between the subpoint O on ground of imaging convergent point P and camera lens center away from From；PO is perpendicular to horizontal plane；O'A' indicates that the pixel distance between O' and A', A' are that the reference point A nearest from camera is being shot The projection of plane, subpoint A' is just at display screen lower boundary；A'B' indicates reference point A and reference point B in photographic plane Subpoint A', B' between pixel distance；β indicates shooting inclination angle；
θ1Indicate the angle between PO and PA, calculation method is as follows:
θ2Indicate the angle between PO and PB, calculation method is as follows:
Wherein, OA indicates the actual range between point O and reference point A；OB indicates the reality between point O and reference point B point Distance；
(4) object height calculates: using step (1) to the photogrammetric parameter of object measurement data and step (3), The photogrammetric height calculation method designed by this patent calculates object actual height, and calculation formula is as follows:
GH=P1O1.(tanγ2-tanγ1).cotγ2 (4)
Wherein: GH indicates the linear distance between the vertex H and object bottom G of object, the i.e. practical height of object Degree；P1O1For the imaging convergent point P of object shooting1Subpoint O with camera lens center on ground1Between linear distance； P1O1Perpendicular to horizontal plane；
γ1Indicate P1O1With P1Angle between G, calculation method are as follows:
γ2Indicate P1O1With P1Angle between H, calculation method are as follows:
Wherein A1' H'=A1'G'+G'H'
PO', O'A' are photogrammetric parameter；A1G' indicates point A1With the pixel distance between point G', A1To be located at after imaging Physical location corresponding to camera display screen lower boundary point, point G' are subpoint of the point G on photographic plane；A1H' indicates point A1 With the pixel distance between point H', point H' is subpoint of the point H on photographic plane.
Digital camera or slr camera or mobile phone is selected to carry out object or reference point photography.
Shooting inclination angle is measured using inclinator.
Pixels tall and pixel distance are measured using reading graph software.
The reading graph software includes Photoshop software.
It is required that object is consistent with total pixel of reference point photography photo regulation.
When photographing to object, reference point, delay screening-mode is selected.
Reference point is two independent objects or there are two an objects of clear reference point for tool.
It is corresponding various shooting inclinations angle can be made the step of the calculating of photogrammetric and photogrammetric parameter according to reference point Photogrammetric parameter list.When practical photogrammetric, replace reference point photogrammetric and photography by inquiring photogrammetric parameter list Measurement parameter calculates step.
Compared with prior art, the beneficial effects obtained by the present invention are as follows being:
Measuring device is simple, easy to carry, of less demanding to operating environment, applied widely；Analysis meter is carried out to photo It calculates, image quality is high, and the measurement precision of correlation distance is high in image；Imaging time is short, has obviously for dynamic object object measurement Advantage.
Detailed description of the invention:
Fig. 1 is that photogrammetric parameter calculates schematic diagram.
Fig. 2 is the photogrammetric schematic diagram of object height.
Specific embodiment
The invention will be further described below in conjunction with the accompanying drawings.Following embodiment is only used for clearly illustrating the present invention Technical solution, and not intended to limit the protection scope of the present invention.
A kind of object height measurement method provided by the invention, includes the following steps:
(1) object is photographed and is measured, measure object shooting height P1O1, shooting angle of inclination beta, photography photo The pixels tall G'H' of middle object, object bottom to photo lower edge vertical pixel distance A1'G'；
When shooting, shooting camera can be placed on tripod, adjust tripod with a distance from object and camera Inclination angle is shot, photographic subjects object photo requires completely to be shown in photo at the top and bottom of object, and object imaging is located at Photo center.Camera is adjusted to delay screening-mode when shooting, the shooting of camera is tilted when tripping to avoid hand The influence at angle.
Shooting height P1O1It can be measured with tape measure, inclinator measurement can be used in shooting angle of inclination beta.
(2) to the photography of reference point and measurement, 2 reference points is placed on ground, appear in it in cameras line, A, B are denoted as respectively from the near to the distant according to the distance away from tripod, using shooting angle of inclination beta identical with step (1) to reference point Photograph, measurement reference point shooting height PO, each reference point to camera lens center the subpoint on ground distance OA, Pixel distance A'B' in OB, photography photo between reference point；
Camera is placed on tripod, from 2 reference points are placed at tripod object suitable distance, reference point can be class Like the miniature object such as bottle cap, subpoint, reference point of the optical center of camera on ground are located along the same line, and at the straight line In the center line of camera display screen.
Pixels tall and pixel distance can be measured using reading graph software, reading graph software such as: Photoshop software.
(3) computational photogrammetry parameter, reference point measurement data OA, OB, PO, A'B' and shooting using step (2) Angle of inclination beta obtains photogrammetric parameter corresponding to the shooting inclination angle of step (2) by photogrammetric calculation method of parameters PO'、O'A'。
As shown in Figure 1, the calculation method of photogrammetric parameter PO', O'A' is as follows:
In figure: P is reference point imaging ray convergent point, and O is camera lens center in the subpoint on ground, and PO is perpendicular to water Plane, height are denoted as shooting height；O' is the intersection point of photographic plane and PO；O'B' is photographic plane；β is inclining vertically for camera Oblique angle, i.e. shooting inclination angle；A, B is 2 reference points being arranged on the ground, wherein A point is close to O point；A', B' are respectively A, B In the projection of photographic plane O'B'；A' is located at the lower boundary of camera display screen.Photogrammetric parameter PO', O'A' can by OA, OB, PO, A'B', β are calculated, and calculating process is as follows:
As shown in Figure 1, note note ∠ O ' PA '=θ1, ∠ O ' PB '=θ2It can be obtained according to sine:
It is obtained by (1), (2) formula:
It can also be obtained by sine:
Photogrammetric parameter O'A' can be obtained by (5) Shi Ke get:
By (6) Shi Ke get:
Photogrammetric parameter PO' can be obtained by (7), (8) formula:
Photogrammetric parameter O'A', PO' corresponding to shooting angle β can be obtained as (7), (9).
(4) actual height for calculating object, utilizes the object measurement data A of step (1)1'G'、G'H'、P1O1, β with And photogrammetric parameter O'A', PO' that step (3) calculates, object actual height is obtained by object height calculation method.
As shown in Fig. 2, the calculating process of object height GH is as follows:
In figure, P1For object imaging ray convergent point, O1Subpoint for camera lens center on ground, P1O1Vertically In horizontal plane, height is denoted as shooting height；O1' H' be photographic plane；O1' be photographic plane and vertical line intersection point；β is phase The vertical inclination angle of machine, i.e. shooting inclination angle；A1To be located at camera display screen lower boundary point A after imaging1' corresponding actual bit It sets；A1' it is A1In the projection of photographic plane；G represents ginseng object bottom, and H represents the top of object, and GH is realistic objective object Highly；G', H' are respectively the projection of G, H in photographic plane；I is P1H extended line and horizontal intersection point.The height of GH can be by clapping Take the photograph corresponding photogrammetric parameter O'A', PO' of angle of inclination beta and A'G', G'H', P1O1, β found out by geometrical relationship.Calculating process It is as follows:
As shown in Fig. 2, note ∠ O1P1G=γ1, ∠ O1P1H=γ2；According to the imaging characteristics of camera it is found that in Fig. 1 PO', O'A' respectively with the P in Fig. 21O1'、O1'A1' equal, then during the height of object calculates, obtained with step (3) Photogrammetric parameter PO', O'A' obtained replaces P1O1'、O1'A1' calculated.
It is obtained by sine:
It is obtained by (15) (16):
Wherein A1' H'=A1' G'+G'H', then from the geometric relations:
O1G=P1O1.tanγ1；
O1I=P1O1.tanγ2；
Therefore the height of realistic objective object are as follows:
GH=P1O1.(tanγ2-tanγ1).cotγ2
The above is only a preferred embodiment of the present invention, it is noted that for the ordinary skill people of the art For member, without departing from the technical principles of the invention, several improvement and deformations can also be made, these improvement and deformations Also it should be regarded as protection scope of the present invention.

Claims (9)

1. a kind of object height measurement method, which comprises the steps of:
(1) to the photography of object and measurement: being photographed using camera to object；Measure shooting height, shooting inclination angle； The pixels tall of object, the vertical pixel distance of object bottom to photo lower edge on metric photography photo；
(2) to the photography of reference point and measurement: placing 2 reference points on ground, make 2 reference points and camera lens center on ground Projection on face is on same straight line, is photographed using shooting inclination angle identical with step (1) to reference point, and measurement is clapped Take the photograph height, each reference point to camera lens center the subpoint on ground distance；On metric photography photo between 2 reference points Pixel distance；
(3) photogrammetric parameter calculates: utilize the reference point measurement data of step (2), computational photogrammetry parameter, specifically such as Under:
Wherein: PO', O'A' are photogrammetric parameter；PO' indicates the linear distance between P and O', and O' is photographic plane and PO Intersection point；PO is the linear distance of imaging the convergent point P and camera lens center of reference point shooting between the subpoint O on ground； PO is perpendicular to horizontal plane；O'A' indicates that the pixel distance between O' and A', A' are the reference point A and imaging convergence nearest from camera The intersection point of line and photographic plane between point P, and A' is just at display screen lower boundary；A'B' indicates that PA, PB and photography are flat Pixel distance between intersection point A', the B' in face；β indicates shooting inclination angle；
θ1Indicate the angle between PO and PA, calculation method is as follows:
θ2Indicate the angle between PO and PB, calculation method is as follows:
Wherein, OA indicates the actual range between point O and reference point A；OB indicates the actual range between point O and reference point B point；
(4) object height calculates: using step (1) to the photogrammetric parameter of object measurement data and step (3), calculating Object actual height, calculation formula are as follows:
GH=P1O1.(tanγ2-tanγ1).cotγ2 (5)
Wherein: GH indicates the linear distance between the vertex H and object bottom G of object, the i.e. actual height of object； P1O1For the imaging convergent point P of object shooting1Subpoint O with camera lens center on ground1Between linear distance；P1O1 Perpendicular to horizontal plane；
γ1Indicate P1O1With P1Angle between G, calculation method are as follows:
γ2Indicate P1O1With P1Angle between H, calculation method are as follows:
Wherein A1' H'=A1'G'+G'H'
PO', O'A' are photogrammetric parameter；A1' G' expression point A1' pixel distance between point G', A1To be located at phase after imaging Physical location corresponding to machine display screen lower boundary point, point G' are GP1With the intersection point of photographic plane；A1' H' expression point A1' and point Pixel distance between H', point H' are HP1With the intersection point of photographic plane.
2. object height measurement method according to claim 1, which is characterized in that select digital camera or slr camera Or mobile phone carries out object or reference point photography.
3. object height measurement method according to claim 1, which is characterized in that utilize inclinator measurement shooting inclination Angle.
4. object height measurement method according to claim 1, which is characterized in that high using reading graph software measurement pixel Degree and pixel distance.
5. object height measurement method according to claim 4, which is characterized in that the reading graph software includes Photoshop software.
6. object height measurement method according to claim 1, which is characterized in that taken the photograph to object, reference point When shadow, delay screening-mode is selected.
7. object height measurement method according to claim 1, which is characterized in that it is required that object and reference point photography Total pixel regulation of photo is consistent.
8. object height measurement method according to claim 1, which is characterized in that reference point is two independent objects Or to have an object there are two clear reference point.
9. object height measurement method according to claim 1, which is characterized in that made according to step (2) and step (3) Make the corresponding photogrammetric parameter list in various shooting inclinations angle, replaces step (2) and step (3) with the photogrammetric parameter list.
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