Summary of the invention
Based on this, it is necessary to a kind of remote sensing image registration method and system based on SUFR algorithm is provided, to improve remote sensing
The speed of service of image registration, and then improve registration efficiency.
To achieve the above object, the present invention provides following schemes:
A kind of remote sensing image registration method based on SUFR algorithm, comprising:
Benchmark remote sensing images and remote sensing images subject to registration are uploaded into GPU video memory;
With parallel calculation in the GPU, using SURF algorithm respectively to benchmark remote sensing images and described
Remote sensing images subject to registration carry out feature extraction, obtain fisrt feature description and second feature description;The fisrt feature is retouched
The Feature Descriptor that son is the benchmark remote sensing images is stated, second feature description is the spy of the remote sensing images subject to registration
Sign description;
Fisrt feature description is retouched with the second feature using quick approximate KNN searching algorithm in GPU
Sub- carry out characteristic matching is stated, characteristic matching image is obtained;
The characteristic matching image is downloaded in CPU memory, the image after being registrated.
Optionally, it is described in the GPU with parallel calculation, using SURF algorithm respectively to the benchmark remote sensing
Image and the remote sensing images subject to registration carry out feature extraction, obtain fisrt feature description and second feature description, specifically
Include:
In GPU by the way of parallel computation respectively to the benchmark remote sensing images and the remote sensing images subject to registration into
Row Integral Processing obtains benchmark remote sensing integral image and remote sensing integral image subject to registration;
The benchmark remote sensing integral image and the remote sensing integral image subject to registration are carried out respectively using SURF algorithm special
Sign detection, obtains fisrt feature parameter and second feature parameter;The fisrt feature parameter is to the benchmark remote sensing integrogram
Location parameter and scale parameter as carrying out the characteristic point that characteristic point detects;The second feature parameter is to described wait match
Quasi- remote sensing integral image carries out the location parameter and scale parameter for the characteristic point that feature detects;
Fisrt feature principal direction is calculated according to the fisrt feature parameter, it is special to calculate second according to the second feature parameter
Levy principal direction;The fisrt feature principal direction is the feature principal direction of the benchmark remote sensing images, and the second feature parameter is
The feature principal direction of the remote sensing images subject to registration;
Fisrt feature description is calculated according to the fisrt feature principal direction, calculates the according to the second feature principal direction
Two Feature Descriptors.
Optionally, described to download to the characteristic matching image in CPU memory, the image after being registrated is specific to wrap
It includes:
The characteristic matching image is downloaded in CPU memory, and the characteristic matching image in CPU memory is had an X-rayed
Matrixing;
Image after transformed characteristic matching image to be determined as to registration.
Optionally, it is described in GPU by the way of parallel computation respectively to benchmark remote sensing images and described wait match
Quasi- remote sensing images carry out Integral Processing, obtain benchmark remote sensing integral image and remote sensing integral image subject to registration, specifically include:
The first pixel value is calculated using row prefix addition algorithm in GPU;First pixel value is the benchmark remote sensing
The sum of the pixel of every a line pixel in image;
It is summed using column prefix addition algorithm to first pixel value in GPU, obtains benchmark remote sensing integrogram
Picture;
The second pixel value is calculated using row prefix addition algorithm in GPU;Second pixel value is described subject to registration distant
Feel the sum of the pixel of every a line pixel in integral image;
It is summed using column prefix addition algorithm to second pixel value in GPU, obtains remote sensing integral subject to registration
Image.
Optionally, described that the benchmark remote sensing integral image and the remote sensing subject to registration are integrated respectively using SURF algorithm
Image carries out feature detection, obtains fisrt feature parameter and second feature parameter, specifically includes:
Convolution algorithm is carried out to the benchmark remote sensing integral image using box filter, obtains the benchmark remote sensing integral
The scale space of image;
Feature detection is carried out to the scale space of the benchmark remote sensing integral image, obtains fisrt feature parameter;
Convolution algorithm is carried out to the remote sensing integral image subject to registration using box filter, obtains the remote sensing subject to registration
The scale space of integral image;
Feature detection is carried out to the scale space of the remote sensing integral image subject to registration, obtains second feature parameter.
The present invention also provides a kind of remote sensing image registration systems based on SUFR algorithm, comprising:
Image uploading module, for uploading to benchmark remote sensing images and remote sensing images subject to registration in GPU video memory;
Characteristic extracting module, in the GPU with parallel calculation, using SURF algorithm respectively to the base
Quasi- remote sensing images and the remote sensing images subject to registration carry out feature extraction, obtain fisrt feature description and second feature description
Son;Fisrt feature description is the Feature Descriptor of the benchmark remote sensing images, and second feature description is described
The Feature Descriptor of remote sensing images subject to registration;
Characteristic matching module, for being described using quick approximate KNN searching algorithm to the fisrt feature in GPU
It is sub to carry out characteristic matching with second feature description, obtain characteristic matching image;
Download module, for the characteristic matching image to be downloaded in CPU memory, the image after being registrated.
Optionally, the characteristic extracting module, specifically includes:
Integral unit, in GPU by the way of parallel computation respectively to the benchmark remote sensing images and it is described to
It is registrated remote sensing images and carries out Integral Processing, obtain benchmark remote sensing integral image and remote sensing integral image subject to registration;
Characteristic detection unit, for using SURF algorithm respectively to the benchmark remote sensing integral image and described subject to registration distant
Feel integral image and carry out feature detection, obtains fisrt feature parameter and second feature parameter;The fisrt feature parameter is to institute
State location parameter and scale parameter that benchmark remote sensing integral image carries out the characteristic point that characteristic point detects;The second feature
Parameter is the location parameter and scale parameter that the characteristic point that feature detects is carried out to the remote sensing integral image subject to registration;
First computing unit, for calculating fisrt feature principal direction according to the fisrt feature parameter, according to described second
Calculation of characteristic parameters second feature principal direction;The fisrt feature principal direction is the feature principal direction of the benchmark remote sensing images,
The second feature parameter is the feature principal direction of the remote sensing images subject to registration;
Second computing unit, for calculating fisrt feature description according to the fisrt feature principal direction, according to described the
Two feature principal directions calculate second feature description.
Optionally, the download module, specifically includes:
Converter unit, for downloading to the characteristic matching image in CPU memory, and to the feature in CPU memory
Perspective matrix transformation is carried out with image;
Determination unit, for transformed characteristic matching image to be determined as the image after being registrated.
Optionally, the integral unit, specifically includes:
First computation subunit, for calculating the first pixel value using row prefix addition algorithm in GPU;First picture
Element value is the sum of the pixel of every a line pixel in the benchmark remote sensing images;
Second computation subunit, for using column prefix addition algorithm to sum first pixel value in GPU,
Obtain benchmark remote sensing integral image;
Third computation subunit, for calculating the second pixel value using row prefix addition algorithm in GPU;Second picture
Element value is the sum of the pixel of every a line pixel in the remote sensing integral image subject to registration;
4th computation subunit, for using column prefix addition algorithm to sum second pixel value in GPU,
Obtain remote sensing integral image subject to registration.
Optionally, the characteristic detection unit, specifically includes:
5th computation subunit, for carrying out convolution algorithm to the benchmark remote sensing integral image using box filter,
Obtain the scale space of the benchmark remote sensing integral image;
First detection sub-unit carries out feature detection for the scale space to the benchmark remote sensing integral image, obtains
Fisrt feature parameter;
6th computation subunit, for carrying out convolution fortune to the remote sensing integral image subject to registration using box filter
It calculates, obtains the scale space of the remote sensing integral image subject to registration;
Second detection sub-unit carries out feature detection for the scale space to the remote sensing integral image subject to registration, obtains
To second feature parameter.
Compared with prior art, the beneficial effects of the present invention are:
The invention proposes a kind of remote sensing image registration method and system based on SUFR algorithm.This method in GPU with
Parallel calculation carries out feature extraction to benchmark remote sensing images and remote sensing images subject to registration respectively using SURF algorithm, obtains
To fisrt feature description and second feature description;Fisrt feature description is the Feature Descriptor of benchmark remote sensing images, the
Two Feature Descriptors are the Feature Descriptor of remote sensing images subject to registration;Quick approximate KNN searching algorithm pair is used in GPU
Fisrt feature description carries out characteristic matching with second feature description, obtains characteristic matching image;It will be under characteristic matching image
It is downloaded in CPU memory, the image after being registrated.The present invention, with parallel calculation, is realized in GPU using SURF algorithm
Feature extraction realizes characteristic matching using quick approximate KNN searching algorithm, can be improved the operation speed of remote sensing image registration
Degree, and then improve registration efficiency.
Specific embodiment
Following will be combined with the drawings in the embodiments of the present invention, and technical solution in the embodiment of the present invention carries out clear, complete
Site preparation description, it is clear that described embodiments are only a part of the embodiments of the present invention, instead of all the embodiments.It is based on
Embodiment in the present invention, it is obtained by those of ordinary skill in the art without making creative efforts every other
Embodiment shall fall within the protection scope of the present invention.
In order to make the foregoing objectives, features and advantages of the present invention clearer and more comprehensible, with reference to the accompanying drawing and specific real
Applying mode, the present invention is described in further detail.
Term is explained:
Box filter (Box filter), quick approximate KNN searching algorithm (Fast Library for
Approximate Nearest Neighbors, Flann).
Fig. 1 is a kind of flow chart of the remote sensing image registration method based on SUFR algorithm of the embodiment of the present invention.
Referring to Fig. 1, the remote sensing image registration method based on SUFR algorithm of embodiment includes:
Step S1: benchmark remote sensing images and remote sensing images subject to registration are uploaded into GPU video memory.
Specifically, the benchmark remote sensing images and the remote sensing images subject to registration are to be sent to GPU video memory by host memory
In.
Step S2: with parallel calculation in the GPU, using SURF algorithm respectively to the benchmark remote sensing images
Feature extraction is carried out with the remote sensing images subject to registration, obtains fisrt feature description and second feature description.
Fisrt feature description is the Feature Descriptor of the benchmark remote sensing images, and the second feature describes son and is
The Feature Descriptor of the remote sensing images subject to registration.
The step S2, specifically includes:
21) in GPU by the way of parallel computation respectively to the benchmark remote sensing images and the remote sensing figure subject to registration
As carrying out Integral Processing, benchmark remote sensing integral image and remote sensing integral image subject to registration are obtained.
The GPU prefix addition algorithm for specifically using Harris in this step, obtains benchmark remote sensing integral image and wait match
Quasi- remote sensing integral image.It is specific:
Firstly, calculating the first pixel value, calculation formula using row prefix addition algorithm in GPU are as follows:
Sx(x, j) indicates the first pixel value, i.e., the sum of the pixel of every a line pixel, I (x, y) table in benchmark remote sensing images
Show that benchmark remote sensing images, (x, y) indicate the coordinate of pixel in benchmark remote sensing images,;Then column prefix addition is used in GPU
Algorithm sums to first pixel value, obtains benchmark remote sensing integral image, calculation formula are as follows:
Wherein S (x, y) is benchmark remote sensing integral image.In row or column prefix addition algorithm, to the behaviour of each row or column
It is completely independent, so this method for completing benchmark remote sensing images integral in two steps is very suitable to come using parallel computation
It speeds up to realize, is able to ascend the speed of operation.
The process for obtaining remote sensing integral image subject to registration is identical as the process for obtaining benchmark remote sensing integral image, is also divided into
Two steps are completed.The second pixel value is calculated using row prefix addition algorithm in GPU;Second pixel value is described subject to registration distant
Feel the sum of the pixel of every a line pixel in integral image;Then use column prefix addition algorithm to second picture in GPU
Plain value is summed, and remote sensing integral image subject to registration can be obtained.
22) the benchmark remote sensing integral image and the remote sensing integral image subject to registration are carried out respectively using SURF algorithm
Feature detection, obtains fisrt feature parameter and second feature parameter;The fisrt feature parameter is to integrate to the benchmark remote sensing
Image carries out the location parameter and scale parameter for the characteristic point that characteristic point detects;The second feature parameter be to it is described to
Registration remote sensing integral image carries out the location parameter and scale parameter for the characteristic point that feature detects.It specifically includes:
A, convolution algorithm is carried out to the benchmark remote sensing integral image using box filter, obtains the benchmark remote sensing product
The scale space of partial image;Feature detection is carried out to the scale space of the benchmark remote sensing integral image, obtains fisrt feature ginseng
Number.Specifically, SURF algorithm is when feature detects building scale space, each tower tomographic image generating process is independent from each other.Cause
This can open one for the generating process of every layer of every width target image among the process of building for carrying out scale space
GPU Parallel Kernel (Workgroup), wherein the size of Workgroup is determined by the size of target image, and each kernel function is main
The calculating of Hessian matrix and Hessian receptance function value is completed, and then obtains the scale space of integral image.Scale space
After building, algorithm obtains scale parameter by scale space, and algorithm carries out the accurate positioning of characteristic point, obtains location parameter.Its
In, in key point position fixing process, SURF algorithm is to carry out threshold decision first, acquires the set of sampling point to be processed, then
The judgement that extreme point is successively carried out using GPU core function carries out size comparison to the extreme value of 26 neighborhood points, to obtain feature
The location parameter of point.
B, convolution algorithm is carried out to the remote sensing integral image subject to registration using box filter, obtained described subject to registration distant
Feel the scale space of integral image;Feature detection is carried out to the scale space of the remote sensing integral image subject to registration, obtains second
Characteristic parameter.The detailed process for obtaining second feature parameter is identical with the above-mentioned process for obtaining fisrt feature parameter.
23) fisrt feature principal direction is calculated according to the fisrt feature parameter, calculates the according to the second feature parameter
Two feature principal directions;The fisrt feature principal direction is the feature principal direction of the benchmark remote sensing images, the second feature ginseng
Number is the feature principal direction of the remote sensing images subject to registration.By the detailed process of calculation of characteristic parameters feature principal direction are as follows:
Due to principal direction calculate with Feature Descriptor (feature vector) seek it is inconsistent in the configuration of thread block, so
Respectively completed with a GPU function call.Wherein the GPU of principal direction is calculated carries out according to two steps of original SURF: every first
A thread calculates the Haar response of a sampled point and is stored in shared memory;Then, per thread calculates a fanlight
Interior vector sum;The maximum vector of mould is stored in by the size for finally comparing the mould of 16 fanlight vector sums of fanlight neighborhood
Shared memory obtains the maximum in shared memory in local modulus maximum value, and the angle of the maximum is the master of this feature
Direction.
24) fisrt feature description is calculated according to the fisrt feature principal direction, according to the second feature principal direction meter
Calculate second feature description.The process for calculating Feature Descriptor by feature principal direction is specific:
Feature vector, that is, Feature Descriptor is generated by the calculated feature principal direction of previous step.SURF feature vector and
Row calculating process is more intuitive, and the feature vector calculating with SURF algorithm is consistent, and has 16 regions since SURF describes son,
16 threads can be used to calculate the feature vector of a characteristic point, per thread calculates a region.The 4*4 around characteristic point
Haar wavelet transformation is calculated in a square subregions domain, and four dimensional vectors can be obtained to indicate each subregion, calculate horizontal direction value
The sum of, the sum of horizontal direction absolute value, the sum of vertical direction, then they are added by the sum of vertical direction absolute value, final to obtain
Feature Descriptor of the vector tieed up to 4*4*4=64 as image.
Step S3: using quick approximate KNN searching algorithm to fisrt feature description and described the in GPU
Two Feature Descriptors carry out characteristic matching, obtain characteristic matching image.It is specific:
Feature is carried out with second feature description to fisrt feature description obtained in the previous step in GPU
Match.The SURF Feature Descriptor extracted is matched using quick approximate KNN searching algorithm in GPU, in order to
Detection speed is improved, before calling matching function, first trains a matcher.Training process can use Flann first
Based Matcher function optimizes, and is characterized descriptor (descriptor) and establishes index tree, in this way will be in a large amount of numbers of matching
According to when, speed is promoted can be very fast.It is as follows using the quick matched partial code of approximate KNN searching algorithm in GPU:
Ptr<cv::cuda::DescriptorMatcher>matcher=
cv::cuda::DescriptorMatcher::createFlannBasedMatcher(surf.defaultNorm
());
vector<DMatch>matches;
matcher->match(descriptors1GPU,descriptors2GPU,matches);// to what is described
Feature point image carries out matching and is put into inside container matches
Step S4: the characteristic matching image is downloaded in CPU memory, the image after being registrated.
The step S4 is specifically included:
The characteristic matching image is downloaded in CPU memory, and the characteristic matching image in CPU memory is had an X-rayed
Matrixing;Image after transformed characteristic matching image to be determined as to registration.It is exactly using the purpose that perspective matrix converts
Image by characteristic matching image projection to a new plane, after being registrated.IDE used in the step is Visual
Studio 2017, exploitation environment are (the open source computer vision library) opencv3.4.1.For calculating perspective transform in opencv3
The function of matrix is cv::getPerspectiveTransform (), its calling form of C++ interface is as follows:
Cv::Mat cv::getPerspectiveTransform//return 3x3 perspective transformation matrix
(const cv::Point2f*src, four apex coordinates of // source images (point array)
The coordinate (point array) on four vertex on const cv::Point2f*dst//target image
);
By calling the cv::getPerspectiveTransform () function, final remote sensing image registration knot is obtained
Fruit, that is, the image after being registrated.
The remote sensing image registration method based on SUFR algorithm in the present embodiment is verified below.
Fig. 2 is first group of remote sensing image registration result figure of the embodiment of the present invention, wherein (a) in Fig. 2 is partially first group
Remote sensing images subject to registration, (b) in Fig. 2 are partially benchmark remote sensing images, and (c) in Fig. 2 is partially for using traditional SURF algorithm
Image after registration, (d) in Fig. 2 is partially for using the image after the algorithm registration in the present embodiment.Fig. 3 is that the present invention is implemented
Second group of remote sensing image registration result figure of example, wherein (a) in Fig. 3 is partially second group of remote sensing images subject to registration, in Fig. 3
It (b) is partially benchmark remote sensing images, (c) in Fig. 3 is partially the image after being registrated using traditional SURF algorithm, (d) in Fig. 3
Part is using the image after the algorithm registration in the present embodiment.
By two methods of the result images of observation comparison, we can intuitively observe the GPU using the present embodiment
The result accuracy for accelerating SURF method more preferably to obtain the effect of unmanned aerial vehicle remote sensing image registration is also higher.And it uses single
SURF algorithm is registrated remote sensing images, and obtained result has apparent distortion, deformation, is not able to satisfy in accuracy and actually answers
Needs.
Table 1 is that tradition Surf algorithm and the present embodiment GPU accelerate SURF algorithm operation efficiency comparing result.
Table 1
Upper table proposes the runing time of two kinds of algorithms with the progress unmanned aerial vehicle remote sensing image registration of both algorithms is respectively adopted
The number for the characteristic point got has done detailed statistics.It is distant in the unmanned plane of equal resolution to this two index comprehensive comparisons
The feature points extracted in sense image using algorithm in the present embodiment are 16 times of SURF algorithm or so, and are calculated than SURF
Under the feature points that 16 times of fado, the runing time for carrying out remote sensing image registration has lacked nearly 3 times.Just because of the present embodiment
The number of characteristic point that can be extracted based on the GPU SURF algorithm accelerated uses this implementation 16 times more than SURF algorithm
The method of example carries out the effect of remote sensing image registration also superior to single SURF algorithm, can satisfy unmanned aerial vehicle remote sensing image registration
Real-time, accuracy, the requirement of robustness can promote high-resolution unmanned aerial vehicle remote sensing image in remote Sensing Image Analysis field
Utilization benefit.
The remote sensing image registration method based on SUFR algorithm of the present embodiment has the advantage that
(1) integral image is generated using prefix addition algorithm in GPU: being totally divided into the parallel side of row and column in GPU
Formula progress pixel value summation add parallel to every a line (or each column) respectively when calculating the sum of the pixel value of row (or column)
The addition of the sum of row and column pixel value is finally obtained the integral image of whole image by method operation.The method of this parallel computation is big
The speed for calculating integral image is improved greatly.
(2) characteristic value is calculated in GPU, obtains characteristic parameter: every in a certain neighborhood of pixel points when calculating characteristic value
The calculating of a characteristic value is all independent, therefore GPU can be used and carry out parallel computation, accelerates the solving speed of characteristic value.
(3) feature principal direction is calculated in GPU: being sought since principal direction is calculated with feature vector (Feature Descriptor)
It is inconsistent in the configuration of thread block, so respectively being completed with a GPU function call.The a certain picture of parallel computation in GPU for the first time
The Haar wavelet transformation of all pixels point in vegetarian refreshments and its neighborhood.All pixels in neighborhood of pixel points are calculated in GPU for the second time
Direction vector, find out the maximum feature principal direction as this feature point, improve the speed of service.
(4) feature vector is acquired in GPU: the GPU calculating process of SURF feature vector is more intuitive, since SURF is described
Son has 16 regions, and 16 threads can be used to calculate the feature vector of a feature, and per thread calculates a region, improves
The speed of service.
(5) characteristic matching is carried out in GPU: in GPU to extracted SURF description son using Flann algorithm into
Row matching, calls Flann Based Matcher function to optimize acceleration, is characterized descriptor in GPU video memory
(descriptor) index tree is established, very fast speed will be promoted when matching mass data in this way.
The present invention also provides a kind of remote sensing image registration systems based on SUFR algorithm, comprising:
Image uploading module, for uploading to benchmark remote sensing images and remote sensing images subject to registration in GPU video memory.
Characteristic extracting module, in the GPU with parallel calculation, using SURF algorithm respectively to the base
Quasi- remote sensing images and the remote sensing images subject to registration carry out feature extraction, obtain fisrt feature description and second feature description
Son;Fisrt feature description is the Feature Descriptor of the benchmark remote sensing images, and second feature description is described
The Feature Descriptor of remote sensing images subject to registration.
Characteristic matching module, for being described using quick approximate KNN searching algorithm to the fisrt feature in GPU
It is sub to carry out characteristic matching with second feature description, obtain characteristic matching image.
Download module, for the characteristic matching image to be downloaded in CPU memory, the image after being registrated.
As an alternative embodiment, the characteristic extracting module, specifically includes:
Integral unit, in GPU by the way of parallel computation respectively to the benchmark remote sensing images and it is described to
It is registrated remote sensing images and carries out Integral Processing, obtain benchmark remote sensing integral image and remote sensing integral image subject to registration.
Characteristic detection unit, for using SURF algorithm respectively to the benchmark remote sensing integral image and described subject to registration distant
Feel integral image and carry out feature detection, obtains fisrt feature parameter and second feature parameter;The fisrt feature parameter is to institute
State location parameter and scale parameter that benchmark remote sensing integral image carries out the characteristic point that characteristic point detects;The second feature
Parameter is the location parameter and scale parameter that the characteristic point that feature detects is carried out to the remote sensing integral image subject to registration.
First computing unit, for calculating fisrt feature principal direction according to the fisrt feature parameter, according to described second
Calculation of characteristic parameters second feature principal direction;The fisrt feature principal direction is the feature principal direction of the benchmark remote sensing images,
The second feature parameter is the feature principal direction of the remote sensing images subject to registration.
Second computing unit, for calculating fisrt feature description according to the fisrt feature principal direction, according to described the
Two feature principal directions calculate second feature description.
As an alternative embodiment, the download module, specifically includes:
Converter unit, for downloading to the characteristic matching image in CPU memory, and to the characteristic matching figure in CPU
As carrying out perspective matrix transformation.
Determination unit, for transformed characteristic matching image to be determined as the image after being registrated.
As an alternative embodiment, the integral unit, specifically includes:
First computation subunit, for calculating the first pixel value using row prefix addition algorithm in GPU;First picture
Element value is the sum of the pixel of every a line pixel in the benchmark remote sensing images.
Second computation subunit, for using column prefix addition algorithm to sum first pixel value in GPU,
Obtain benchmark remote sensing integral image.
Third computation subunit, for calculating the second pixel value using row prefix addition algorithm in GPU;Second picture
Element value is the sum of the pixel of every a line pixel in the remote sensing integral image subject to registration.
4th computation subunit, for using column prefix addition algorithm to sum second pixel value in GPU,
Obtain remote sensing integral image subject to registration.
As an alternative embodiment, the characteristic detection unit, specifically includes:
5th computation subunit, for carrying out convolution algorithm to the benchmark remote sensing integral image using box filter,
Obtain the scale space of the benchmark remote sensing integral image.
First detection sub-unit carries out feature detection for the scale space to the benchmark remote sensing integral image, obtains
Fisrt feature parameter.
6th computation subunit, for carrying out convolution fortune to the remote sensing integral image subject to registration using box filter
It calculates, obtains the scale space of the remote sensing integral image subject to registration.
Second detection sub-unit carries out feature detection for the scale space to the remote sensing integral image subject to registration, obtains
To second feature parameter.
The remote sensing image registration system based on SUFR algorithm of the present embodiment is used with parallel calculation in GPU
SURF algorithm realizes feature extraction, realizes characteristic matching using quick approximate KNN searching algorithm, can be improved remote sensing images
The speed of service of registration, and then improve registration efficiency.
For the system disclosed in the embodiment, since it is corresponded to the methods disclosed in the examples, so the ratio of description
Relatively simple, reference may be made to the description of the method.
Used herein a specific example illustrates the principle and implementation of the invention, and above embodiments are said
It is bright to be merely used to help understand method and its core concept of the invention;At the same time, for those skilled in the art, foundation
Thought of the invention, there will be changes in the specific implementation manner and application range.In conclusion the content of the present specification is not
It is interpreted as limitation of the present invention.