CN101261730A - Video digitalized large-scale imaging method - Google Patents

Abstract

The invention discloses a digital large scale mapping method of an optical impression which includes the following steps: (1) the optical impression is converted into a digital image and the digital image is deposited in the memorizer of a computer; (2) the actual coordinate of control points on the image is obtained and input; (3) a corresponding relation between the actual control points and the corresponding points in the digital image is built; (4) a mapping scale is given; (5) correcting treatment is carried out on each point in the digital image by utilizing a two-dimensional mathematics transformation model and according to the transformation situation of the control points in the image and the mapping scale; (6) the image is output after correcting treatment; the number N of the control points in one image is five. The digital large scale mapping method of the optical impression of the invention needs few control points; the actual measuring time in the field has low effect on the mapping period; the whole correcting mapping can be accomplished by adopting the devices like a desktop micro-computer or a notebook computer; the cost of hardware is low and the treatment is convenient.

Description

The digitizing large scale drawing methods of video

Technical field

The present invention relates to a kind of image processing method, be specifically related to a kind of utilization and take photo by plane and resemble sheet or other similar video and carry out digitizing and correct, make large-scale plan and use for city-building.

Background technology

Utilize aerophoto to become the method for figure to make map, complete atural object, geomorphology information are arranged, advantage such as the field survey workload is few, and speed is fast.Owing to resemble the influence that has numerous factors such as height displacement that droop error, optical distortion, atmosphere refractive power, the distortion of film emulsion and surface irregularity cause in the sheet shooting process, make each image point that resembles in the sheet deform, it is a system variant, but have randomness, want high precision, eliminate these distortion simply, apace, and can make the cities and towns large-scale plan, be one of important topic of photogrammetric technology development in modern age in fact.

Be corrected to figure in early days, its objective is to eliminate to resemble the distortion that sheet tilts to cause, obtain a level of having unified engineer's scale and resemble sheet, the instrument of use is the optical mechanical rectification instrument, and its manufacturing process is strongly professional, complex process.Since the eighties because the development of digitizing technique, produced digital rectification, its principle and the external common practice, the works " photogrammetric principle is sequeled " that sees famous academician Mr. Wang Zhizhuo for details is (1986.7 editions) P.184-P.187, but video is corrected the mathematical model of handling, if utilize polynomial expression to approach then to think the video deformation rule be translation, convergent-divergent, rotation, affine, turn round partially, basic distortion such as bending is synthetic, its correction member can be up to 40 remainders, and the reference mark that required specification is arranged is wanted 30-40.The mathematical model of this correction distortion, plan with the difficulty of scheming just to have in the realization making the cities and towns large scale, for this reason, aerophoto to be used to make the cities and towns large-scale map, must change existing method, make drafting period short, the precision height, the field survey workload alleviates, and professional operation is weak and expense is low, could adapt to actual the use.

On the other hand, the existing two-dimensional mathematics model that is used to be corrected to figure is difficult to realize accurate correction.And the city planning that commercial digital Photogrammetric System also is difficult to accurately, makes in large quantity 1: 1000 or 1: 500 is with figure.

Summary of the invention

The object of the invention provides a kind of digitizing large scale drawing methods of video, can directly utilize Computer Processing to the videos such as resembling sheet of taking photo by plane, and simultaneously, required reference mark is few, and drafting period is short.

For achieving the above object, the technical solution used in the present invention is: a kind of digitizing large scale drawing methods of video, comprise the following steps,

(1) converts video to digitized image, and leave in the storer of computing machine;

(2) selected reference mark, obtain and input picture on the actual coordinate at reference mark;

(3) set up the corresponding relation between the corresponding point in working control point and the digitized image;

(4) each point in the digitized image is corrected processing;

(5) image after handling is corrected in output;

In described step (4), at first set map scale for, utilize the two-dimensional mathematics transformation model again, according to the distortion situation and the preset scale at reference mark in the image each point in the digitized image is corrected processing;

In the described two-dimensional mathematics transformation model, be in order to the modification value of describing video point x direction,

${\mathrm{\ω}}_1(x,y)=A_1+B_{1}x+C_{1}y+\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{F}_i{r}_i^2\ln r_i^2;$

In order to the modification value of describing video point y direction be,

${\mathrm{\ω}}_2(x,y)=A_2+B_{2}x+C_{2}y+\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{F}_i{r}_i^2\ln r_i^2;$

In the formula, r _i ²=(x-x _i) ²+ (y-y _i) ²I=1 is to N

The number N at the reference mark on the described images is 5.

The thinking of above-mentioned correction disposal route derives from the data processing of two-dimentional variable function.In interpolation calculation, the method for Tui Jianing is line splines (splines) the most, and its physical significance is, elastic beam when small deformation, balance equation y ⁴(x)=q _iSeparate q wherein _iIt is the load that i is ordered on the beam; We extend to two-dimentional variable with it according to physical significance, can obtain elastic sheet, during small deformation, and balance equation $D\·{\▿}^4\mathrm{\ω}(x,y)=q_i(i=1,N)$ Separate, its mathematical form is exactly top equation, promptly the distortion that resembles sheet is regarded as the distortion of elastic sheet.Obviously, N+3 unknown number arranged in the formula, i.e. A, B, C, F ₁, F ₂, F ₃, F ₄, F ₅, if restitution point N=5 then has 8 unknown numbers in the formula, utilize the measured data at 5 reference mark,, promptly can obtain the unknown number of above-mentioned linear equation again according to equilibrium condition, in view of the above, can provide the deformation values of video each point, realize that the video of fully digitalization is corrected.

Wherein, described two-dimensional mathematics transformation model utilizes actual coordinate, the coordinate of reference mark in digitized image, the coordinate of point in digitized image that need correct at reference mark, obtain the one-tenth figure coordinate of the point that needs correction, what obtain that a width of cloth unified engineer's scale resembles sheet figure, is depicted as planimetric map through accent according to this.

Further technical scheme, described 5 reference mark evenly distribute on entire image, and the actual coordinate at reference mark adopts the field survey mode to obtain.4 points lay respectively in the overlapping scope of four jiaos of adjoining sheets, and 1 point is positioned at the middle part of map sheet, and the field survey mode at described reference mark is the GPS locator meams.Because one-tenth figure need carry out the processing of several continuous map sheets when handling usually, forming required map, thereby, selected 4 jiaos reference mark in the overlapping scope of adjoining sheet, can with the adjoining sheet dual-purpose, reduce the workload of reference mark field survey.

Because the technique scheme utilization, the present invention compared with prior art has following advantage:

1, because the present invention adopts the two-dimensional mathematics model to be corrected to figure, the reference mark that needs is few, and promptly the metric data of sampling on the spot at reference mark is few, and control survey, correction handle and accent is painted and can be finished by first phase on the spot, have shortened drafting period greatly, and becomes the figure expense low;

2, because mathematical model of the present invention is a two dimensional model, and calculated amount is little, thereby the whole figure of being corrected to can adopt microcomputers such as desktop computer, or even adopts notebook computer to finish, and hardware cost is low, and it is convenient to handle;

3, adopt method of the present invention, be particularly suitable for making large-scale planimetric map.

Description of drawings

Accompanying drawing 1 is the method schematic block diagram of the embodiment of the invention one;

Accompanying drawing 2 is that the video of handling in the embodiment of the invention one resembles sheet figure;

Accompanying drawing 3 is planimetric maps of handling back output through the embodiment of the invention one.

Embodiment

Below in conjunction with embodiment the present invention is further described, present embodiment only for further understanding the present invention and actual effect thereof, does not impose any restrictions protection scope of the present invention:

Embodiment one: a kind of digitizing large scale drawing methods of video, comprise the following steps,

(1) utilizes scanner object sheet to scan, convert video to digitized image, and leave in the internal memory of computing machine;

(2) 5 reference mark on the selected digital image, and field survey reference mark coordinate are with the actual coordinate input computing machine at reference mark;

(3) utilize the position of figure enlarging function and mouse specified control point on image, set up corresponding point in working control point and the digitized image between corresponding relation;

(4) given preset scale, preset scale can be selected according to the needs of publishing picture, and generally selected for use 1: 500,1: 1000 or 1: 2000 when carrying out large scale one-tenth figure.

(5) utilize the two-dimensional mathematics transformation model, the each point in the digitized image is corrected processing according to the distortion situation and the preset scale at reference mark in the image;

In the described two-dimensional mathematics transformation model, be in order to the modification value of describing video point x direction,

${\mathrm{\ω}}_1(x,y)=A_1+B_{1}x+C_{1}y+\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{F}_i{r}_i^2\ln r_i^2;$

In order to the modification value of describing video point y direction be,

${\mathrm{\ω}}_2(x,y)=A_2+B_{2}x+C_{2}y+\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{F}_i{r}_i^2\ln r_i^2;$

In the formula, r _i ²=(x-x _i) ²+ (y-y _i) ²I=1 to 5

Utilize actual coordinate, the coordinate of reference mark in digitized image, the coordinate of point in digitized image that need correct at reference mark, obtain the one-tenth figure coordinate of the point that needs correction;

(6) utilize on the image of mapping software (as CASS software) after processing is corrected in output, draw the required planimetric map of setting map scale for through transferring.

For verifying effect of the present invention, utilize the method for present embodiment to carry out following test:

(1) according to correction mathematical model method of the present invention, take the photograph with suburb, Shanghai City boat and to copy photo again, resemble engineer's scale 1/M=1/4500, repeatedly adopt the mechanical measuring method, measured the image point coordinate of 150 discrete points, after correcting by this mathematical model, through field examination, it is as shown in table 1 below that it corrects precision:

Table 1 precision statistics list position: m

Annotate: it is 0.02mm that Mechanical Method measures the image point coordinate precision

(2) referring to accompanying drawing 2 and accompanying drawing 3, the planimetric map that is respectively a width of cloth correction figure and finishes resembles ratio 1/M=1/8000, corrects figure with its digital image of making 1: 1000, and map face: 60cm * 70cm corrects and controls the N=5 that counts.

Claims (3)

1. the digitizing large scale drawing methods of a video comprises the following steps,

(1) converts video to digitized image, and leave in the storer of computing machine;

(2) selected reference mark, obtain and input picture on the actual coordinate at reference mark;

(3) set up the corresponding relation between the corresponding point in working control point and the digitized image;

(4) each point in the digitized image is corrected processing;

(5) image after handling is corrected in output;

It is characterized in that: in described step (4), at first set map scale for, utilize the two-dimensional mathematics transformation model again, the each point in the digitized image is corrected processing according to the distortion situation and the preset scale at reference mark in the image;

In the described two-dimensional mathematics transformation model, be in order to the modification value of describing video point x direction,

${\mathrm{\ω}}_1(x,y)=A_1+B_{1}x+C_{1}y+\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{F}_i{r_i}^2\ln {r_i}^2;$

In order to the modification value of describing video point y direction be,

${\mathrm{\ω}}_2(x,y)=A_2+B_{2}x+C_{2}y+\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{F}_i{r_i}^2\ln {r_i}^2;$

In the formula, r _i ²=(x-x _i) ²+ (y-y _i) ²I=1 is to N

The number N at the reference mark on the described images is 5.

2. the digitizing large scale drawing methods of video according to claim 1 is characterized in that: described 5 reference mark evenly distribute on entire image, and the actual coordinate at reference mark adopts the field survey mode to obtain.

3. the digitizing large scale drawing methods of video according to claim 2, it is characterized in that: described 5 reference mark are, 4 points lay respectively in the overlapping scope of four jiaos of adjoining sheets, 1 point is positioned at the middle part of map sheet, and the field survey mode at described reference mark is the GPS locator meams.

Images