It is a kind of based on iconic model draw freedom can measure panorama reproducting method
Technical field
The invention belongs to Remote Sensing Information System technical field, being related to a kind of freedom drawn based on iconic model can be measured entirely
Scape reproducting method.
Background technique
Large information capacity, high-precision, visualization are the developing direction of current remote sensing information service, and target is to provide body for user
The service of the property tested, Communicating, otherness, creativeness and relevance.Visuality is the basis of experience property, and can measure on demand is to create
The premise of property and otherness, space-time can excavate, and provide technical guarantee for the professional application of relevance.Full-view image can be measured, it is simultaneous
Tool is visual and scalability, as the important means of visualization of spatial information, can full view show scene and measurement letter be provided
Breath, has complied with the development trend of remote sensing information service.
Current panorama system, either ground streetscape or aviation panorama are used as a kind of ideal view exhibition mould more
Formula, though being widely used in the fields such as cityscape and various Guide to Venues, industrial simulation, information visualization, there are still offices
It is sex-limited.They can only provide at shooting point or on baseline simple visual angle interpolation scene reproduction, can not carry out except baseline
The scene information of its concern, therefore greatly limit are reflected in the scene drawing of any spatial point, the visual angle that cannot arbitrarily need from user
The freedom degree of scene observation is made.In addition, the panorama system for view exhibition does not have scalability also usually, i.e., do not demarcate
The absolute exterior orientation information of picture elements affects sky to can not also provide the quantitative description of scene content spatial position
Between information judging accuracy.
Summary of the invention
Technical problem solved by the present invention is overcome the deficiencies of the prior art and provide it is a kind of based on iconic model draw
Panorama reproducting method can freely be measured.This method has both the true of the independence and space geometry measure information for observing viewpoint selection
Property, greatly enhance the sense of reality of user experience, so that sight can be measured to " the free eye " of real scene using mobile terminal realization
It examines no longer remote.
The technical solution of the invention is as follows: it is a kind of based on iconic model draw freedom can measure panorama reproducting method,
Include the following steps:
1) ground full-view image data are collected;
2) it obtains through satellite or the GIS image data taken photo by plane;
3) GIS image data and ground full-view image data are registrated, the matching dotted line that both obtains and mensurable
Information;
4) triangle gridding of metrical information is generated;
5) triangle gridding of the metrical information obtained according to step 4), carry out free view-point measures panorama reproduction.
The ground full-view image data acquired in the step 1) have accurately geographical empty to have been subjected to interior external calibration
Between azimuth information.
When carrying out full-view image acquisition in ground in the step 1), selection carries the roadbed traverse measurement system of Position and attitude sensor
System directly obtains calibrated ground full-view image data, or the ground panorama shadow for selecting common filming apparatus to complete single frames shooting
As the external calibration of data, or to the ground full-view image data of multiframe shooting, using multi-angle of view bundle adjustment method, in conjunction with several
Ground control point obtains the accurate elements of exterior orientation of all ground full-view image data.
When the step 2) obtains GIS image data, in Remote Sensing Database, addition achieves high-resolution satellite or boat
It claps remote sensing images and the latitude and longitude information of each pixel is obtained using Geotiff format.
The step 3) method particularly includes:
31) straightway is extracted to GIS image data;
32) straightway is extracted to ground full-view image data, further extracts end point, the ground for obtaining different directions is flat
The clusters of line segments of row clusters of line segments and vertical-horizontal ground;
33) straightway of GIS image data is projected on the imaging surface of ground full-view image data, by complete with ground
Ground parallel segment cluster comparison on scape image data obtains matched line between the two, and the intersection point of these matched lines is made
For match point, obtained matching the mensurable of dotted line in the full-view image data of ground by the pixel latitude and longitude information of GIS image data
Information, including geographical location information.
The step 4) method particularly includes:
41) it to adjacent ground full-view image data, is registrated by feature dotted line, obtains adjacent ground full-view image data
Matching dotted line, ground scene information is subjected to triangle division, and through consistency checking, is divided into adjacent ground full-view image number
According to consistency triangle pair and nonuniformity triangle pair;
42) the matching dotted line being registrated according to GIS image data in step 3) and ground full-view image data, it is raw
At the initial triangulation lattice of GIS image;
43) correspondence of the matching dotted line of the adjacent ground full-view image data generated by step 41) on GIS image is found
Dotted line, and dotted line is corresponded to as triangle gridding vertex using this, triangular gridding subdivision is carried out, GIS image data is obtained and ground is complete
The triangle pair of scape image data carries out triangle gridding description to the horizontal plane of different height.
The consistency triangle pair and nonuniformity triangle pair of adjacent ground full-view image data are raw in the step 41)
At detailed process are as follows: first to the ground full-view image data of external calibration by characteristic point line drawing be registrated to obtain a large amount of
With dotted line, triangular grids are then carried out, consistency checking is carried out to each pair of triangular mesh, passes through consistency checking
Consistency triangle pair can be considered from the conplane projection in space, be determined as visibility uniform domain;Do not pass through consistency
The nonuniformity triangle pair of judgement need to further find match point and further segment, then the consistency checking through a new round divides
For consistency triangle pair and nonuniformity triangle pair, such several wheels of iteration, last remaining nonuniformity triangle pair quilt
It is determined as visibility region of variation.
The detailed process of the step 5) are as follows:
51) it to any virtual view of specified geographical space, i.e. free view-point, retrieves and surrounds the most adjacent of the free view-point
Close several ground full-view image data, according to the distance difference of closest several ground full-view image data to free view-point
Different weights is set, the weighting of consistency triangle pair is remapped to free view-point, and obtain the mensurable letter in the region
Breath;
52) it to the remaining perforated being not mapped in free view-point image planes, searches whether by other full-view image data
Consistency triangle pair region overlay, cover if it exists, then map corresponding consistency triangle pair and filled up, if not depositing
Then selecting the nonuniformity triangle pair of closest ground full-view image data or GIS image data in this area maps face
Product it is maximum carry out mapping fill up;To the metrical information of the perforated from ground full-view image data projection by surrounding this
The fixed metrical information of perforated carries out interpolating estimation and obtains, to from the perforated that GIS image data projects
Metrical information can directly obtain, thus complete free view-point measure panorama reproduction.
It is arranged in the step 51) according to the distance difference of closest several ground full-view image data to free view-point
The detailed process of different weights are as follows: be arranged using the weighting function being positively correlated with inverse distance.
It is arranged in the step 51) according to the distance difference of closest several ground full-view image data to free view-point
The detailed process of different weights are as follows: by the spatial position of free view-point position and closest several ground full-view image data
Between distance reflection weight size reciprocal, i.e., it is big apart from close weight, it is small apart from remote weight.
The present invention has the advantages that
(1) though, the present invention derived from what is occurred on the market measure live-action image system, but breach its viewpoint and fix
Limitation, can the total space carry out the drafting of virtual view panorama;
(2), the drawing viewpoints that the present invention is different from conventional virtual reality make due to injecting and having expanded geography information
Full-view image must be reproduced and have scalability;
(3), present invention combination ground full-view image data and GIS image data complete large scale scene reproduction, play
The two advantage (GIS image data covers vertical view imaging on a large scale, and ground full-view image data provide abundant side-information), effectively
It ensure that the high presence of any virtual viewpoint rendering, simultaneously because involving in for GIS image data is greatly broadened virtual view
The overlay area of point, to enter larger range of seamless virtual roaming from sky;
(4), the present invention can measure the free view-point that the rendering technique based on iconic model promotes the use of large scale scene
It surveys panorama to reproduce, not only mitigates data acquisition and procession burden, more take into account independence and obtain on demand empty that observation viewpoint is chosen
Between geological information accuracy, can be described as virtual reality and photogrammetric primary completely new combination in some sense.
Detailed description of the invention
Fig. 1 is that a kind of freedom drawn based on iconic model of the present invention can measure panorama reproducting method work flow diagram.
Specific embodiment
The invention proposes a kind of freedom drawn based on iconic model can measure panorama reproducting method, will be based on image mould
The free view-point that the rendering technique of type promotes the use of large scale scene can measure panorama reproduction, with a small amount of sampled point ground panorama
Image can be obtained the satisfied free view-point of accuracy in measurement and draw, it is ensured that the independence and obtain on demand empty that observation viewpoint is chosen
Between geological information accuracy.Panorama can be measured for a kind of freedom drawn based on iconic model of the present invention as shown in Figure 1 to reproduce
Method work flow diagram, the present invention is divided into five steps and completes, specific as follows:
Step (1): acquisition ground full-view image data.
Using roadbed traverse measurement system acquisition streetscape panorama sketch, the main side grain information for reflecting ground landscape.Road
Base traverse measurement system mainly includes two parts: determining appearance positioning system and imaging sensor system.The former generally uses high-precision
Degree dynamic difference GPS and Inertial Measurement Unit IMU integrated positioning determine appearance.The latter generally uses CCD digital camera cluster, with VISAT
For traverse measurement system, 6~12 digital viewing field of camera angles, which overlap each other, constitutes 330 degree of full-view visual field imaging, every 5
The synchronous exposure of rice is primary, and ensure that the same object is at least imaged in three cameras, due to being had been subjected in stringent between camera
Outer calibration can splice through automatic light and color homogenization and joint treatment and generate a width full-view image.By high accuracy positioning attitude determination system
The absolute geographical grid bearing of every frame image can be accurately obtained.Some is also equipped with Two-dimensional Pulsed formula laser scanner, can generate
Three-dimensional point cloud, the laser point cloud after calibration can also provide the absolute orientation information of image pixel, but which increase costs
With the workload of system calibration.System for being fitted without laser scanner can pass through the vertical of calibrated adjacent image
Body imaging obtains the spatial position of image pixel.
If also can choose the business panorama camera such as Ladybug without roadbed traverse measurement system and carry out ground panorama shadow
As data acquire, it might even be possible to use homemade panorama shooting device, obtain ground through profession splicing software by stringent internal calibration
Face full-view image data.To multiframe ground full-view image data, multi-angle of view bundle adjustment method can be used, in conjunction with several ground
Control point obtains the accurate elements of exterior orientation of each frame ground full-view image data.To single frames ground full-view image data, can be used
Patent " a kind of geographic positioning of ground full-view image ", be not necessarily to manual control point and accurate elevation model, by with middle height
Resolution Satellite Image registration completes the external calibration of single frames ground full-view image data under relative altitude sequence constraint independent of time.
Step (2): it obtains through satellite or the GIS image data taken photo by plane
In Remote Sensing Database, addition achieves high-resolution satellite remote sensing images, these images use Geotiff lattice
Formula, each pixel both provide latitude and longitude information.If lacking the satellite remote-sensing image of observation area, can also fly to be navigated by navigating
Image is clapped, such as space base traverse measurement system.Space base traverse measurement system is equipped with aerial camera, GPS (global positioning system), determines
Determine the advanced sensors such as appearance measuring instrument in position.Due to the unstability of airborne platform, positioning and orientation error is also larger, directly relies on position
The output of appearance sensor is corrected simultaneously inaccurately figure of taking photo by plane, and generallys use bundle adjustment, and sky three encrypts, and tie surface controls
Point realizes that image joint and ortho-rectification generate Geotiff data.Pix4D mapper is the Airborne Data Classification of a profession
Processing software can be well solved platform shakiness bring processing difficulty.
Step (3): being registrated GIS image data and ground full-view image data, the matching dotted line that both obtains and
Metrical information
1) ground is parallel in ground full-view image data, extraction of vertical-horizontal ground clusters of line segments
Straightway is extracted to ground full-view image data, further extracts end point.According to space parallel lines in panorama
Projection extended line in image data must give a bit (end point), cluster, obtain to the parallel segment for having identical end point
Multiple clusters of line segments have been arrived, and end point also defines the direction of different clusters of line segments.For urban environment, the side grain of building
It is substantially sketched the contours by parallel or vertical-horizontal ground line segment, by clustering, can be convenient and identify different directions
The clusters of line segments of ground parallel segment cluster and vertical level.
2) line segment extraction of GIS image data
For GIS image data, building top surface profile is extracted using Level Set Method, is then fitted, mentions through straightway
Construction ceiling profile straightway is taken out, due to being orthography, these straightways are basically parallel to level ground.
3) GIS image data and ground full-view image data are registrated, the matching dotted line that both obtains and mensurable
Information
The straightway of GIS image projects on the panoramic imagery face of ground full-view image data, by comparing ground panorama
Ground parallel segment cluster on image data, available matched line between the two can also determine the friendship of these matched lines
Point is match point, the actual position of several known Points And lines in the full-view image data of ground is obtained, apart from the mensurable letter such as size
Breath, these can be used as control point and control line is dissolved into step (4).
Step (4): the triangle gridding of metrical information is generated
To the adjacent ground full-view image data of external calibration in, obtained using SURF feature point extraction and registration Algorithm
With point, triangle gridding is constructed as vertex;Edge is obtained using Canny operator and extracts straightway with curvature control strategy,
And describe son with MSLD and be described, tensor constraint should be met according to mapping line segment of the space line in three different views,
Further reject error hiding straightway;It is constraint further subdivision triangle gridding with matching line section;Adjacent view triangulation network structure
At the triangle pair of registration, triangle pair vertex can determine three spatial points, according to the absolute geographical coordinate of view and side
Position is estimated that the actual position of three spatial points, the absolute spatial position of plane where can also deducing three spatial points;Three
It is angular to whether there is by the space plane that consistency check determines that three spatial points are constituted, then space plane three if it exists
Point in angular domain all has absolute spatial position, that is, provides metrical information, if it does not exist, finds in triangle interior
The match point further division triangulation network, then consistency checking is carried out one by one.It decomposes always according to the above method, can obtain more
Consistency triangle pair, remaining non-uniform triangle pair is substantially blocked as caused by the difference of visual angle, is shown especially etc. visible
Property region of variation, they be only used as in free view-point drawing process perforated fill up rather than space geometry (amount
Survey) transmitting of information.
GIS image data can obtain some by being registrated for step (3) with multiple views ground full-view image data
Wiring and match point are constrained the initial triangulation lattice for generating GIS image data, and multiple views ground full-view image by these dotted lines
A large amount of matching Points And lines that Registration of Measuring Data generates, can also further find its correspondence dotted line on GIS image data, execute
The further subdivision of triangle gridding, to obtain making with the triangle gridding of different height horizontal plane to GIS image data
It obtains the triangle gridding that GIS image provides overlook view and has metrical information.
Step (5): free view-point measures panorama reproduction
Any virtual view of geographical space, i.e. free view-point are specified for user, are retrieved and are surrounded the closest of the point
Several ground full-view image data and GIS image data, according to closest several ground full-view image data to freely regarding
Different weights is arranged in the distance difference of point ,-weighting of consistent triangle pair is remapped to free view-point, and obtain the area
The metrical information in domain;To the remaining perforated being not mapped in free view-point image planes, search whether by other full-view images
The consistency triangle pair region overlay of data, covers if it exists, then maps corresponding consistency triangle pair and filled up, if
It is not present, then the nonuniformity triangle pair of closest ground full-view image data or GIS image data is selected to reflect in this region
Penetrate area it is maximum carry out mapping fill up.To the metrical information of the perforated from ground full-view image data projection by wrapping
The fixed metrical information for enclosing this perforated carries out interpolating estimation and obtains, to the hole projected from GIS image data
The metrical information in region can directly obtain, so that the panorama that measures for completing free view-point reproduces.