CN105488776B - Super-resolution image reconstruction method and device - Google Patents

Super-resolution image reconstruction method and device Download PDF

Info

Publication number
CN105488776B
CN105488776B CN201410532272.6A CN201410532272A CN105488776B CN 105488776 B CN105488776 B CN 105488776B CN 201410532272 A CN201410532272 A CN 201410532272A CN 105488776 B CN105488776 B CN 105488776B
Authority
CN
China
Prior art keywords
resolution
resolution image
low
represent
image
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
CN201410532272.6A
Other languages
Chinese (zh)
Other versions
CN105488776A (en
Inventor
章勇勤
郭宗明
刘家瑛
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
New Founder Holdings Development Co ltd
Peking University
Beijing Founder Electronics Co Ltd
Original Assignee
Peking University
Peking University Founder Group Co Ltd
Beijing Founder Electronics Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Peking University, Peking University Founder Group Co Ltd, Beijing Founder Electronics Co Ltd filed Critical Peking University
Priority to CN201410532272.6A priority Critical patent/CN105488776B/en
Publication of CN105488776A publication Critical patent/CN105488776A/en
Application granted granted Critical
Publication of CN105488776B publication Critical patent/CN105488776B/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Landscapes

  • Image Processing (AREA)

Abstract

The present invention, which provides a kind of super-resolution image reconstruction method and device, this method, to be included:N times are carried out according to the first high-definition picture and obscure down-sampling, generate high resolution image data storehouse, fuzzy down-sampling is carried out using bicubic interpolation algorithm to the first high-definition picture, fuzzy up-sampling obtains the first low-resolution image, carry out n times and obscure down-sampling, generation low resolution image data storehouse;The second low-resolution image is obtained after first high-definition picture is amplified S times, and is divided at least one low-resolution image piece;And the corresponding most like image sheet group of low resolution is obtained in low resolution image data storehouse using approximate KNN searching algorithm;Weight coefficient is calculated using Ridge Regression Method to the most like image sheet group of low resolution and determines high resolution graphics photo.The second high-definition picture is determined using weighted average to high resolution graphics photo, so as to effectively reduce the error of rebuilding super resolution image, improves the quality for rebuilding image in different resolution.

Description

Super-resolution image reconstruction method and device
Technical field
The present invention relates to image, field of video processing, more particularly to a kind of super-resolution image reconstruction method and device.
Background technology
With developing rapidly for multimedia technology, visual vivid effect and abundant picture of the people for image and video The requirement of detailed information is higher and higher, this needs high-resolution image and video, and in actual image processing and analysis In system, high-resolution image and video are generally also required for.Set however, the resolution ratio of image is generally limited by Image Acquisition The restriction conditions such as standby, optics, image taking speed and hardware store, what is captured in many imaging applications is all the image of low resolution And video, for example, digital camera, medical image system and video monitoring system capture usually be all low resolution image and Video.So in order to obtain high-resolution image and video, it is necessary to which super-resolution technique goes to utilize the low resolution figure obtained Picture and video reconstruct high-resolution image and video.
Existing super-resolution image reconstruction method has:Method based on interpolation, the method based on reconstruction and Case-based Reasoning The method of study, wherein the method based on reconstruction needs extra database, for the low-resolution image of acquisition, utilizes image The priori of a variety of images in database is modeled current low-resolution image, then, by low point after modeling Resolution image reconstruction is high-resolution image.
But conventionally, as what is utilized when being modeled to super-resolution image is one huge representative Low resolution and high resolution graphics photo it is as much as possible including all picture structures to data storehouse, the database so that weigh Build that super-resolution image process is excessively complicated, and usually there will be the feelings that can not restore high frequency detail based on the image data base Condition.
The content of the invention
The present invention provides a kind of super-resolution image reconstruction method and device, so as to effectively reduce rebuilding super resolution The error of image, and then improve the quality of reconstruction image.
In a first aspect, the present invention provides a kind of super-resolution image reconstruction method, including:Step S1, by low point of input Resolution image y is as the first high-definition pictureAccording to first high-definition pictureCarry out n times and obscure down-sampling, Generate high resolution image data storehouse Dx;Step S2, to first high-definition pictureUsing bicubic interpolation algorithm into Row, which obscures down-sampling and then carries out fuzzy up-sampling, obtains the first low-resolution imageFor first low resolution ImageCarry out n times and obscure down-sampling, generation low resolution image data storehouse Dz;Step S3, is calculated using the bicubic interpolation Method is by first high-definition pictureThe second low-resolution image is obtained after S times of amplificationBy second low resolution ImageIt is divided at least one low-resolution image piece;Step S4, to each low-resolution image piece using approximate nearest Adjacent searching algorithm is in the low resolution image data storehouse DzObtain the corresponding most like image sheet group of low resolution;Step S5, Weight coefficient is calculated using Ridge Regression Method to the most like image sheet group of the low resolution;Step S6, according to the weight coefficient High resolution graphics photo is determined with the most like image sheet group of high-resolution;Step S7, uses the high resolution graphics photo and adds Weight average determines the second high-definition pictureAnd by second low-resolution imageIt is added to the database DzIn, By second high-definition pictureIt is added to the database DxIn.
With reference to first aspect, in the first possible embodiment of first aspect, further include:Step S8, by described Two high-definition picturesAs the first new high-definition pictureAfter repeating step S3-S7 by M times, obtain 3rd high-definition pictureUsing the bicubic interpolation algorithm to the 3rd high-definition pictureCarry out under obscuring Sampling, generates initial target high-definition picture
The first possible embodiment with reference to first aspect, in second of possible embodiment of first aspect, also Including:Step S9, to the initial target high-definition pictureAlternating minimization algorithm is used with the low-resolution image y Calculate mathematical model:
s.t.hf=hr,
Wherein, the initial value of the x in above-mentioned mathematical model is initial target high-definition pictureDegenerate matrix H represents mould Paste down-sampling operator, λ1And λ2Represent regularization parameter, αiIt is the high resolution graphics photo x of target high-resolution image xiIt is dilute Sparse coefficient, α αiSet, βiIt is αiNon-local mean in sparse coding domain, ο represent the sparse coefficient matrix α of all splicings With the product of super complete dictionary φ,Represent gradient operation symbol, f is transforming function transformation function, hrBe target high-resolution image reference it is straight Fang Tu, hfIt is the histogram of transforming function transformation function f.
Second of possible embodiment with reference to first aspect, in the third possible embodiment of first aspect, institute State to the initial target high-definition pictureMathematical modulo is calculated using alternating minimization algorithm with the low-resolution image y Type specifically includes:Step S10, super complete dictionary is obtained using K mean cluster algorithm and Principal Component Analysis Algorithm;Step S11, root Algorithm, which is remained unchanged, according to histogram of gradients updates the transforming function transformation function f;Step S12, according to the super complete dictionary and the change Exchange the letters number f updates the initial target high-definition picture.
The third possible embodiment with reference to first aspect, in the 4th kind of possible embodiment of first aspect, is adopted Super complete dictionary is obtained with K mean cluster algorithm and Principal Component Analysis Algorithm, is specifically included:K is randomly selected according to size The high resolution graphics photo of a initial target high-definition picture is as K initial clustering;According to the high resolution graphics The distance between photo and the K initial cluster center, the initial target high-definition picture are divided into all The high resolution graphics photo be divided into corresponding initial clustering;Each initial clustering is used based on singular value point The corresponding sub- dictionary of Principal Component Analysis training of solution;The K corresponding K sub- dictionary composition of the initial clustering super complete words Allusion quotation.
The third possible embodiment with reference to first aspect, in the 5th kind of possible embodiment of first aspect, according to Histogram of gradients remains unchanged algorithm and updates the transforming function transformation function f, specifically includes:The low-resolution image y is obscured Sampling, obtains low-resolution image z;The target high-resolution image x and the low-resolution image z meet following condition:Z= B*x, wherein B are fuzzy core;Gradient is asked to z=B*x both sides, thenWherein b0And biPoint Not Biao Shi fuzzy core B center coefficient and its surrounding's neighbour's coefficient,Represent the gradient image of target high-resolution image x,Represent the gradient image of the low-resolution image z,Represent the gradient image of the target high-resolution image sheet;OrderIfIt is similar to normal distribution, then
Pass through solving-optimizing problems.t.hf=hrTo update transforming function transformation function f.
Wherein hrRepresent the terraced histogram of reference of target high-resolution image x, hzRepresent the ladder of the low-resolution image z Spend histogram, hx1It is the discrete form of the probability density function of stochastic variable x1, hx2It is the general of I.i.d. random variables x2 The discrete form of rate density function,It is convolution operation symbol.
The third possible embodiment with reference to first aspect, in the 6th kind of possible embodiment of first aspect, institute State and the initial target high-definition picture is updated according to the super complete dictionary and the transforming function transformation function f, specifically include:According to FormulaDetermine x(t+1/2), wherein x(t)Represent the t times iteration Target high-resolution Image estimation value, x(t+1/2)Represent the target high-resolution Image estimation value of the t+1/2 times iteration, δ is Constant,Represent x(t)Gradient map;According toDetermineWhereinRepresent t+1/ The high resolution graphics photo x of 2 iterationiSparse coefficient,Represent the high resolution graphics photo x of the t times iterationiPlace is initial Cluster corresponding sub- dictionary, RiRepresent from initial target high-definition pictureHigh resolution graphics photo x is obtained at the i of positioni's Matrix.
According to sparse coefficientWithDetermine the high resolution graphics photo x of the t+1 times iterationiSparse coefficientωiJ-th of component ωijMeet:Wherein h represents to be used for the control parameter for adjusting the rate of decay, W expression normalizings Change the factor,Represent high resolution graphics photo xiJ-th of most like image sheet in corresponding most like image sheet group, Sλ/cTable Show soft-threshold function, c represents regularization parameter;According to formula Determine x(t+1), wherein x(t+1)Represent the target high-resolution Image estimation value of the t+1 times iteration, φ(t+1)Represent x(t+1)It is corresponding Super complete dictionary.
The third possible embodiment or the 4th kind of possible embodiment with reference to first aspect or the 5th kind of possible implementation Mode or the 6th kind of possible embodiment, in the 7th kind of possible embodiment of first aspect, further include:Repeat step S10-S12, acquisition convergence solution are final goal high-definition picture x ';Using plural impact filtering formula to the final goal High-definition picture is restored, wherein the plural number impact filtering formula is:
Wherein, x ' expressions final goal high-definition picture, x " represent the final goal high-definition picture after restoring,Represent the gradient map of x', η and ξ represent the gradient direction of image, and Im () represents extraction imaginary part, and a represents to be used to control image The adjusting parameter of acutance, τ=| τ | exp (i θ) is complex scalar coefficient,It is real number scalar factor.
Second aspect, the present invention provide a kind of super-resolution image reconstruction device, including:Generation module, for that will input Low-resolution image y as the first high-definition pictureAccording to first high-definition pictureN times are carried out to obscure Down-sampling, generation high resolution image data storehouse Dx;The generation module, is additionally operable to first high-definition pictureAdopt Fuzzy down-sampling, which is carried out, with bicubic interpolation algorithm and then carries out fuzzy up-sampling obtaining the first low-resolution imageIt is right In first low-resolution imageCarry out n times and obscure down-sampling, generation low resolution image data storehouse Dz;Division module, For using the bicubic interpolation algorithm by first high-definition pictureThe second low resolution figure is obtained after S times of amplification PictureBy second low-resolution imageIt is divided at least one low-resolution image piece;Acquisition module, for each A low-resolution image piece is using approximate KNN searching algorithm in the low resolution image data storehouse DzObtain corresponding low The most like image sheet group of resolution ratio;Computing module, based on using Ridge Regression Method to the most like image sheet group of the low resolution Calculate weight coefficient;Determining module, for determining high-resolution according to the weight coefficient and the most like image sheet group of high-resolution Image sheet;The determining module, is additionally operable to determine the second high resolution graphics using weighted average to the high resolution graphics photo PictureAnd by second low-resolution imageIt is added to the database DzIn, by second high-definition picture It is added to the database DxIn.
With reference to second aspect, in the first possible embodiment of second aspect, further include:The acquisition module, also For obtaining the 3rd high-definition pictureThe generation module is also high to the described 3rd using the bicubic interpolation algorithm Image in different resolutionFuzzy down-sampling is carried out, generates initial target high-definition picture
With reference to the first possible embodiment of second aspect, in second of possible embodiment of second aspect, go back Including:The computing module, is additionally operable to the initial target high-definition pictureWith the low-resolution image y using friendship Mathematical model is calculated for algorithm is minimized:
s.t. hf=hr,
Wherein, the initial value of the x in above-mentioned mathematical model is initial target high-definition pictureDegenerate matrix H represents mould Paste down-sampling operator, λ1And λ2Represent regularization parameter, αiIt is the high resolution graphics photo x of target high-resolution image xiIt is dilute Sparse coefficient, α αiSet, βiIt is αiNon-local mean in sparse coding domain, ο represent the sparse coefficient matrix α of all splicings With the product of super complete dictionary φ,Represent gradient operation symbol, f is transforming function transformation function, hrBe target high-resolution image reference it is straight Fang Tu, hfIt is the histogram of transforming function transformation function f.
With reference to second of possible embodiment of second aspect, in the third possible embodiment of second aspect, go back Including:Update module;The acquisition module, is additionally operable to obtain using K mean cluster algorithm and Principal Component Analysis Algorithm super complete Dictionary;The update module, updates the transforming function transformation function f for remaining unchanged algorithm according to histogram of gradients;The renewal mould Block, updates the initial target high-definition picture always according to the super complete dictionary and the transforming function transformation function f.
With reference to the third possible embodiment of second aspect, in the 4th kind of possible embodiment of second aspect, institute Acquisition module is stated to be specifically used for:The high-resolution of the K target high-resolution images is randomly selected according to size Image sheet is as K initial clustering;According to the distance between the high resolution graphics photo and the K initial cluster center, All high resolution graphics photos that the target high-resolution image is divided into are divided into corresponding initial clustering In;To each initial clustering using the corresponding sub- dictionary of Principal Component Analysis training based on singular value decomposition;K described first Begin to cluster the corresponding K sub- dictionary composition super complete dictionary.
With reference to the third possible embodiment of second aspect, in the 5th kind of possible embodiment of second aspect, institute Update module is stated to be specifically used for:Fuzzy up-sampling is carried out to the low-resolution image y, obtains low-resolution image z;The mesh Absolute altitude image in different resolution x and the low-resolution image z meet following condition:Z=B*x, wherein B are fuzzy core;To z=B*x Gradient is sought on both sides, thenWherein b0And biThe center coefficient of fuzzy core B is represented respectively And its surrounding's neighbour's coefficient,Represent the gradient image of target high-resolution image x,Represent the low-resolution image The gradient image of z,Represent the gradient image of the high resolution graphics photo;OrderIfIt is similar to normal distribution, then
Pass through solving-optimizing problems.t. hf=hrTo update transforming function transformation function f.
Wherein hrRepresent the terraced histogram of reference of target high-resolution image x, hzRepresent the ladder of the low-resolution image z Spend histogram, hx1It is the discrete form of the probability density function of stochastic variable x1, hx2It is the general of I.i.d. random variables x2 The discrete form of rate density function,It is convolution operation symbol.
With reference to the third possible embodiment of second aspect, in the 6th kind of possible embodiment of second aspect, institute Update module is stated to be specifically used for:According to the iterative solution formula of super-resolution optimization problem
Determine x(t+1/2), wherein x(t)Represent the t times iteration Target high-resolution Image estimation value, x(t+1/2)Represent the target high-resolution Image estimation value of the t+1/2 times iteration, δ is normal Number,Represent x(t)Gradient map;According toDetermineWhereinRepresent the t+1/2 times The high resolution graphics photo x of iterationiSparse coefficient,Represent the high resolution graphics photo x of the t times iterationiPlace initial clustering Corresponding sub- dictionary, RiRepresent from initial target high-definition pictureHigh resolution graphics photo x is obtained at the i of positioniMatrix;Root According to sparse coefficientWith Determine the high resolution graphics photo x of the t+1 times iterationiSparse coefficientωiJ-th of component ωijMeet:Wherein h represents the control parameter for adjusting the rate of decay, and W represents normalization factor, Represent high resolution graphics photo xiJ-th of most like image sheet in corresponding most like image sheet group, Sλ/cRepresent soft-threshold letter Number, c represent regularization parameter;According to formulaDetermine x(t+1), its Middle x(t+1)Represent the target high-resolution Image estimation value of the t+1 times iteration, φ(t+1)Represent x(t+1)Corresponding super complete dictionary.
It may implement with reference to the third possible embodiment of second aspect or the 4th kind of possible embodiment or the 5th kind Mode or the 6th kind of possible embodiment, in the 7th kind of possible embodiment of second aspect, further include:Filter module;Institute It is final goal high-definition picture x ' to state acquisition module and obtain convergence solution;The filter module, for being filtered using plural number impact Ripple formula restores the final goal high-definition picture, wherein the plural number impact filtering formula is:
Wherein, x ' expressions final goal high-definition picture, x " represent the final goal high-definition picture after restoring,Represent the gradient map of x', η and ξ represent the gradient direction of image, and Im () represents extraction imaginary part, and a represents to be used for control figure As the adjusting parameter of acutance, τ=| τ | exp (i θ) is complex scalar coefficient,It is real number scalar factor.
The present invention provides a kind of super-resolution image reconstruction method, including:Using the low-resolution image of input as first High-definition picture, carries out n times according to first high-definition picture and obscures down-sampling, generate high resolution image data Storehouse, carries out fuzzy down-sampling and then obscures to adopt to first high-definition picture using bicubic interpolation algorithm Sample obtains the first low-resolution image, and carrying out n times for first low-resolution image obscures down-sampling, generates low resolution Image data base;Second low point is obtained after first high-definition picture is amplified S times using the bicubic interpolation algorithm Resolution image, at least one low-resolution image piece is divided into by second low-resolution image;To each low resolution Image sheet is most like in the corresponding low resolution of low resolution image data storehouse acquisition using approximate KNN searching algorithm Image sheet group;Weight coefficient is calculated using Ridge Regression Method to the most like image sheet group of the low resolution;According to the weight system Number and the most like image sheet group of high-resolution determine high resolution graphics photo.Weighted average is used to the high resolution graphics photo Determine the second high-definition picture, initial target high resolution graphics is estimated by the multistage amplifying technique based on Ridge Regression Method Picture, and comprehensively utilize data fidelity, sparse non local regularization and histogram of gradients regularization priori and carry out mathematical modeling, Final target high-resolution image is obtained by duty Optimization, edge is further sharpened finally by impact filtering With recovery picture structure treatment of details so as to effectively reduce the error of rebuilding super resolution image, and then improve reconstruction image Quality.
Brief description of the drawings
Fig. 1 is a kind of flow chart for super-resolution image reconstruction method that one embodiment of the invention provides;
Fig. 2 is the flow chart for the super-resolution image reconstruction method that another embodiment of the present invention provides;
Fig. 3 is a kind of super-resolution image reconstruction apparatus structure schematic diagram that one embodiment of the invention provides;
Fig. 4 is a kind of super-resolution image reconstruction apparatus structure schematic diagram that another embodiment of the present invention provides.
Embodiment
To make the purpose, technical scheme and advantage of the embodiment of the present invention clearer, below in conjunction with the embodiment of the present invention In attached drawing, the technical solution in the embodiment of the present invention is clearly and completely described, it is clear that described embodiment is Part of the embodiment of the present invention, instead of all the embodiments.Based on the embodiments of the present invention, those of ordinary skill in the art All other embodiments obtained without making creative work, belong to the scope of protection of the invention.
Fig. 1 is a kind of flow chart for super-resolution image reconstruction method that one embodiment of the invention provides, wherein this method Scene suitable for obtaining high-definition picture or video, the executive agent of wherein this method are:Super-resolution image reconstruction Device, the device can be that intelligent terminal, the super-resolution image reconstruction methods such as computer specifically include following flow:
Step S1, using the low-resolution image of input as the first high-definition picture, according to the first high-definition picture Carry out n times and obscure down-sampling, generation high resolution image data storehouse.
Wherein, low-resolution image is represented with y, and the first high-definition picture is usedRepresent, high resolution image data storehouse Use DxRepresent.
Step S2, fuzzy down-sampling and then progress are carried out to the first high-definition picture using bicubic interpolation algorithm Fuzzy up-sampling obtains the first low-resolution image, and carrying out n times for the first low-resolution image obscures down-sampling, generates low point Resolution image data base.
Wherein, the first low-resolution image is usedRepresent, low resolution image data storehouse DzRepresent, in same scale level The first low-resolution image on notWith the first high-definition pictureBetween correspondence establish it is as follows:Wherein, * is convolution operation symbol, and ↑ s is that the up-sampling that scale factor is s operates Symbol, ↓ s are the down-sampling operators that scale factor is s, and B is fuzzy core, EsIt is the scale factor that first fuzzy down-sampling up-samples again For the operator that meets of s, then the first low-resolution image is obtainedFor the first low-resolution imageN times are carried out to obscure down Sampling, generation low resolution image data storehouse Dz
Step S3, the second low resolution is obtained after the first high-definition picture is amplified S times using bicubic interpolation algorithm Image, at least one low-resolution image piece is divided into by the second low-resolution image.
Wherein, the second low-resolution image isSpecifically,And by the second low-resolution imageDraw It is divided at least one low-resolution image piece.
Step S4, to each low-resolution image piece using approximate KNN searching algorithm in low resolution image data Storehouse obtains the corresponding most like image sheet group of low resolution.
Step S5, weight coefficient is calculated to the most like image sheet group of the low resolution using Ridge Regression Method.
Specifically, approximate KNN searching algorithm is may be by from low resolution for any one low-resolution image piece Image data base DzThe corresponding most like image sheet group of low resolution of middle search, such as:Assuming that low-resolution image piece ziIt is corresponding The most like image sheet group of low resolution is Lpi, then using Ridge Regression Modeling Method to ziAnd LpiBetween linear approximate relationship built The constrained optimization problem that mould is formed is as follows:Wherein, γ is weight coefficient, and τ is to be used to alleviate Singularity problem and the regularization parameter for stablizing solution.By solving this regular least square regression problem, the present invention gives Go out the closed solutions of the problem:Wherein, I is unit matrix.
Step S6, high resolution graphics photo is determined according to the weight coefficient and the most like image sheet group of high-resolution.
By z in step S5iWith LpiMapping relations from low resolution image data storehouse DzIt is applied to high-definition picture number According to storehouse Dx, then high resolution graphics photo piWith the most like image sheet group Hp of high-resolutioniRelational expression be pi=Hpiγ。
Step S7, the second high-definition picture is determined to high resolution graphics photo using weighted mean method, and by described in Second low-resolution image is added in the database, and second high-definition picture is added in the database.
Wherein, the second high-definition picture is
The present invention provides a kind of super-resolution image reconstruction method, including:Using the low-resolution image of input as first High-definition picture, carries out n times according to first high-definition picture and obscures down-sampling, generate high resolution image data Storehouse, carries out fuzzy down-sampling and then obscures to adopt to first high-definition picture using bicubic interpolation algorithm Sample obtains the first low-resolution image, and carrying out n times for first low-resolution image obscures down-sampling, generates low resolution Image data base;Second low point is obtained after first high-definition picture is amplified S times using the bicubic interpolation algorithm Resolution image, at least one low-resolution image piece is divided into by second low-resolution image;To each low resolution Image sheet is most like in the corresponding low resolution of low resolution image data storehouse acquisition using approximate KNN searching algorithm Image sheet group;Weight coefficient is calculated using Ridge Regression Method to the most like image sheet group of the low resolution;According to the weight system Number and the most like image sheet group of high-resolution determine high resolution graphics photo.Weighted average is used to the high resolution graphics photo Method determines the second high-definition picture, estimates initial target high resolution graphics by the multistage amplifying technique based on Ridge Regression Method Picture, so as to effectively reduce the error of rebuilding super resolution image, and then improves the quality of reconstruction image.
Fig. 2 is the flow chart for the super-resolution image reconstruction method that another embodiment of the present invention provides, which is to build Stand on upper embodiment basis, performed after upper embodiment step S7, wherein specifically including:
Step S8, using the second high-definition picture as the first new high-definition picture, step is repeated by M times After S3-S7, the 3rd high-definition picture is obtained, the 3rd high-definition picture is obscured down using bicubic interpolation algorithm Sampling, generates initial target high-definition picture.
Wherein, the 3rd high-definition picture isInitial target high-definition pictureIt is it is noted that of the invention Employing and repeating in step S3-S7 M times is based on when scale factor is smaller, low-resolution image and high-definition picture What this more like factor considered.Therefore, in view of natural image in scale domain and spatial domain there are a large amount of self-similarity redundancies, Different from traditional bicubic interpolation method, method of the present invention is using the multistage amplifying technique based on Ridge Regression Method come just Beginningization target high-resolution image.It is to use successive ignition magnification scheme, when single amplification method is taken by multistage amplifying technique Dai Hou, the scale factor in every grade of amplification procedure of the present invention is just very small, so as to be searched from low-resolution image storehouse Rope is used for high resolution image reconstruction to more similar diagram photos.Low-resolution image y for width input and given General size factor d, the cascade in multistage amplification procedure of the present invention are confirmed as Wherein s is the scale factor in every grade of amplification.
Step S9, mathematics is calculated to initial target high-definition picture and low-resolution image using alternating minimization algorithm Model:
s.t. hf=hr,
Wherein, the initial value of the x in above-mentioned mathematical model is initial target high-definition pictureDegenerate matrix H represents mould Paste down-sampling operator, λ1And λ2Represent regularization parameter, αiIt is the high resolution graphics photo x of target high-resolution image xiIt is dilute Sparse coefficient, α αiSet, βiIt is αiNon-local mean in sparse coding domain, ο represent the sparse coefficient matrix α of all splicings With the product of super complete dictionary φ,Represent gradient operation symbol, f is transforming function transformation function, hrBe target high-resolution image reference it is straight Fang Tu, hfIt is the histogram of transforming function transformation function f.
Specifically, the initial target high-definition picture determined in step S1-S8May not be most for the mathematical model Excellent solution, it is therefore desirable to continuous iteration, untill obtaining convergence solution.Wherein, it is described to the target high-resolution image x and institute Low-resolution image y is stated to specifically include using alternating minimization algorithm calculating mathematical model:
Step S10, super complete dictionary is obtained using K mean cluster algorithm and Principal Component Analysis Algorithm.
Specifically, super complete dictionary is obtained using K mean cluster algorithm and Principal Component Analysis Algorithm, specifically included:According to Size randomly selects the high resolution graphics photo of the K target high-resolution images as K initial clustering;Root According to the distance between the high resolution graphics photo and the K initial cluster center, by the target high-resolution image institute All high resolution graphics photos being divided into are divided into corresponding initial clustering;Each initial clustering is used The corresponding sub- dictionary of Principal Component Analysis training based on singular value decomposition;The corresponding K sub- dictionary composition of the described initial clusterings of K The super complete dictionary.
Step S11, algorithm renewal transforming function transformation function is remained unchanged according to histogram of gradients.
Wherein, transforming function transformation function f, alternatively, remains unchanged algorithm according to histogram of gradients and updates the transforming function transformation function f, Specifically include:Fuzzy up-sampling is carried out to the low-resolution image y, obtains low-resolution image z;The target high-resolution Image x and the low-resolution image z meet following condition:Z=B*x, wherein B are fuzzy core;Gradient is asked to z=B*x both sides, ThenWherein b0And biRepresent respectively fuzzy core B center coefficient and it around it is near Adjacent coefficient,Represent the gradient image of target high-resolution image x,Represent the gradient image of the low-resolution image z,Represent the gradient image of the high resolution graphics photo;OrderIfClosely Normal distribution is similar to, then
Pass through solving-optimizing problems.t.hf=hrTo update transforming function transformation function f;Wherein hrTable Show the terraced histogram of reference of target high-resolution image x, hzRepresent the histogram of gradients of the low-resolution image z, hx1Be with The discrete form of the probability density function of machine variable x1, hx2It is the discrete of the probability density function of I.i.d. random variables x2 Form,It is convolution operation symbol.
Step S12, updates target high-resolution image according to super complete dictionary and transforming function transformation function.
It is specifically, described that the initial target high-definition picture is updated according to the super complete dictionary and the transforming function transformation function f, Specifically include:According to the iterative solution formula of super-resolution optimization problem Determine x(t+1/2), wherein x(t)Represent the target high-resolution Image estimation value of the t times iteration, x(t+1/2)Represent the t+1/2 times repeatedly The target high-resolution Image estimation value in generation, δ is constant,Represent x(t)Gradient map;According to DetermineWhereinRepresent the high resolution graphics photo x of the t+1/2 times iterationiSparse coefficient,Represent the t times The high resolution graphics photo x of iterationiThe corresponding sub- dictionary of place initial clustering, RiRepresent from initial target high-definition picture High resolution graphics photo x is obtained at the i of positioniMatrix.
According to sparse coefficientWithDetermine the high resolution graphics photo x of the t+1 times iterationiSparse coefficientωiJ-th of component ωijMeet:Wherein h represents to be used for the control parameter for adjusting the rate of decay, W expression normalizings Change the factor,Represent high resolution graphics photo xiJ-th of most like image in corresponding most like image sheet group, Sλ/cRepresent Soft-threshold function, c represent regularization parameter;According to formulaReally Determine x(t+1), wherein x(t+1)Represent the target high-resolution Image estimation value of the t+1 times iteration, φ(t+1)Represent x(t+1)It is corresponding super Complete dictionary.Circulation performs S10-S12, untill the target high-resolution image of acquisition is convergence solution.
Further, step S10-S12 is repeated, acquisition convergence solution is final goal high-definition picture x;Using multiple Number impact filtering formula restores the final goal high-definition picture, wherein the plural number impact filtering formula is:
Wherein, x ' expressions final goal high-definition picture, x " represent the final goal high-definition picture after restoring,Represent the gradient map of x', η and ξ represent the gradient direction of image, and Im () represents extraction imaginary part, and a represents to be used to control image The adjusting parameter of acutance, τ=| τ | exp (i θ) is complex scalar coefficient,It is real number scalar factor.
Super-resolution image reconstruction method provided in this embodiment comprehensively utilizes data fidelity, sparse non local regularization Mathematical modeling is carried out with histogram of gradients regularization priori, final target high-resolution is obtained by duty Optimization Image, edge is further sharpened finally by impact filtering and recovers picture structure treatment of details.
Fig. 3 is a kind of super-resolution image reconstruction apparatus structure schematic diagram that one embodiment of the invention provides, the wherein dress Put including:Generation module 301, for using the low-resolution image y of input as the first high-definition pictureAccording to described One high-definition pictureCarry out n times and obscure down-sampling, generation high resolution image data storehouse Dx;The generation module 301, also For to first high-definition pictureFuzzy down-sampling is carried out using bicubic interpolation algorithm and then is carried out on fuzzy Sampling obtains the first low-resolution imageFor first low-resolution imageCarry out n times and obscure down-sampling, generate Low resolution image data storehouse Dz;Division module 302, for using the bicubic interpolation algorithm by first high-resolution ImageThe second low-resolution image is obtained after S times of amplificationBy second low-resolution imageIt is divided at least one Low-resolution image piece;Acquisition module 303, for being existed to each low-resolution image piece using approximate KNN searching algorithm The low resolution image data storehouse DzObtain the corresponding most like image sheet group of low resolution;Computing module 304, for institute State low resolution most like image sheet group and weight coefficient is calculated using Ridge Regression Method;Determining module 305, for according to the weight Coefficient and the most like image sheet group of high-resolution determine high resolution graphics photo;The determining module 305, is additionally operable to the height Resolution chart photo determines the second high-definition picture using weighted mean methodAnd by second low-resolution image It is added to the database DzIn, by second high-definition pictureIt is added to the database DxIn.
Super-resolution image reconstruction device provided in this embodiment, can be used for performing the super-resolution figure corresponding to Fig. 1 As the implementation technical solution of method for reconstructing, its implementing principle and technical effect is similar, and details are not described herein again.
Fig. 4 is a kind of super-resolution image reconstruction apparatus structure schematic diagram that another embodiment of the present invention provides, at Fig. 3 pairs Answer on embodiment basis, the acquisition module 303, be additionally operable to obtain the 3rd high-definition pictureThe generation module 301, also using the bicubic interpolation algorithm to the 3rd high-definition pictureFuzzy down-sampling is carried out, generates initial mesh Absolute altitude image in different resolutionThe computing module 304, is additionally operable to the initial target high-definition pictureWith described low point Resolution image y calculates mathematical model using alternating minimization algorithm:
s.t. hf=hr,
Wherein, the initial value of the x in above-mentioned mathematical model is initial target high-definition pictureDegenerate matrix H is represented Fuzzy down-sampling operator, λ1And λ2Represent regularization parameter, αiIt is the high resolution graphics photo x of target high-resolution image xi's Sparse coefficient, α αiSet, βiIt is αiNon-local mean in sparse coding domain, ο represent the sparse coefficient square of all splicings The product of battle array α and super complete dictionary φ,Represent gradient operation symbol, f is transforming function transformation function, hrIt is the ginseng of target high-resolution image Examine histogram, hfIt is the histogram of transforming function transformation function f.
Further, which further includes:Update module 306;The acquisition module 303, is additionally operable to use K mean cluster Algorithm and Principal Component Analysis Algorithm obtain super complete dictionary;The update module 306, for being remained unchanged according to histogram of gradients Algorithm updates the transforming function transformation function f;The update module 306, updates always according to the super complete dictionary and the transforming function transformation function f The initial target high-definition picture.
Alternatively, the acquisition module 303 is specifically used for:The K target high-resolution are randomly selected according to size The high resolution graphics photo of rate image is as K initial clustering;According to described to the high resolution graphics photo and the K The distance between a initial cluster center, all high resolution graphics that the target high-resolution image is divided into Photo is divided into corresponding initial clustering;Principal Component Analysis based on singular value decomposition is used to each initial clustering The corresponding sub- dictionary of training;The K corresponding K sub- dictionary composition of the initial clustering super complete dictionaries.
Alternatively, the update module 306 is specifically used for:Fuzzy up-sampling is carried out to the low-resolution image y, is obtained Low-resolution image z;The target high-resolution image x and the low-resolution image z meet following condition:Z=B*x, wherein B For fuzzy core;Gradient is asked to z=B*x both sides, thenWherein b0And biRepresent fuzzy core B's respectively Center coefficient and its surrounding's neighbour's coefficient,Represent the gradient image of target high-resolution image x,Represent described low point The gradient image of resolution image z,Represent the gradient image of the high resolution graphics photo;Order IfIt is similar to normal distribution, then
Pass through solving-optimizing problems.t. hf=hrTo update transforming function transformation function f;
Wherein hrRepresent the terraced histogram of reference of target high-resolution image x, hzRepresent the ladder of the low-resolution image z Spend histogram, hx1It is the discrete form of the probability density function of stochastic variable x1, hx2It is the general of I.i.d. random variables x2 The discrete form of rate density function,It is convolution operation symbol.
Further, the update module 306 is specifically used for:According to iterative solution formula
Determine x(t+1/2), wherein x(t)Represent the t times iteration Target high-resolution Image estimation value, x(t+1/2)Represent the target high-resolution Image estimation value of the t+1/2 times iteration, δ is Constant,Represent x(t)Gradient map;According toDetermineWhereinRepresent t+1/2 The high resolution graphics photo x of secondary iterationiSparse coefficient,Represent the high resolution graphics photo x of the t times iterationiPlace is initial Cluster corresponding sub- dictionary, RiRepresent from initial target high-definition pictureHigh resolution graphics photo x is obtained at the i of positioni's Matrix;According to sparse coefficient correction formula WithDetermine the high resolution graphics photo x of the t+1 times iterationiSparse coefficientωiJ-th of component ωijMeet:Wherein h represents to be used for the control parameter for adjusting the rate of decay, W expression normalizings Change the factor,Represent high resolution graphics photo xiJ-th of most like image sheet in corresponding most like image sheet group, Sλ/cTable Show soft-threshold function, c represents regularization parameter;According to formula Determine x(t+1), wherein x(t+1)Represent the target high-resolution Image estimation value of the t+1 times iteration, φ(t+1)Represent x(t+1)It is corresponding Super complete dictionary.
Further, further include:Filter module 307;It is final goal high score that the acquisition module 303, which obtains convergence solution, Resolution image x ';The filter module 307, for using plural impact filtering formula to the final goal high-definition picture Restored, wherein the plural number impact filtering formula is:
Wherein, x ' expressions final goal high-definition picture, x " represent the final goal high-definition picture after restoring,Represent the gradient map of x', η and ξ represent the gradient direction of image, and Im () represents extraction imaginary part, and a represents to be used to control image The adjusting parameter of acutance, τ=| τ | exp (i θ) is complex scalar coefficient,It is real number scalar factor.
Super-resolution image reconstruction device provided in this embodiment, can be used for performing the super-resolution figure corresponding to Fig. 2 As the implementation technical solution of method for reconstructing, its implementing principle and technical effect is similar, and details are not described herein again.
One of ordinary skill in the art will appreciate that:Realizing all or part of step of above-mentioned each method embodiment can lead to The relevant hardware of programmed instruction is crossed to complete.Foregoing program can be stored in a computer read/write memory medium.The journey Sequence upon execution, execution the step of including above-mentioned each method embodiment;And foregoing storage medium includes:ROM, RAM, magnetic disc or Person's CD etc. is various can be with the medium of store program codes.
Finally it should be noted that:The above embodiments are merely illustrative of the technical solutions of the present invention, rather than its limitations;Although The present invention is described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that:It still may be used To modify to the technical solution described in foregoing embodiments, or equivalent substitution is carried out to which part technical characteristic; And these modification or replace, do not make appropriate technical solution essence depart from various embodiments of the present invention technical solution spirit and Scope.

Claims (16)

  1. A kind of 1. super-resolution image reconstruction method, it is characterised in that including:
    Step S1, using the low-resolution image y of input as the first high-definition pictureAccording to first high resolution graphics PictureCarry out n times and obscure down-sampling, generation high resolution image data storehouse Dx
    Step S2, to first high-definition pictureUsing bicubic interpolation algorithm carry out fuzzy down-sampling and then into The fuzzy up-sampling of row obtains the first low-resolution imageFor first low-resolution imageProgress n times, which obscure down, adopts Sample, generation low resolution image data storehouse Dz
    Step S3, using the bicubic interpolation algorithm by first high-definition pictureIt is low that second is obtained after S times of amplification Image in different resolutionBy second low-resolution imageIt is divided at least one low-resolution image piece;
    Step S4, to each low-resolution image piece using approximate KNN searching algorithm in the low resolution image data Storehouse DzObtain the corresponding most like image sheet group of low resolution;
    Step S5, weight coefficient is calculated to the most like image sheet group of the low resolution using Ridge Regression Method;
    Step S6, high resolution graphics photo is determined according to the weight coefficient and the most like image sheet group of high-resolution;
    Step S7, the second high-definition picture is determined to the high resolution graphics photo using weighted mean methodAnd by institute State the second low-resolution imageIt is added to the database DzIn, by second high-definition pictureIt is added to the number According to storehouse DxIn.
  2. 2. according to the method described in claim 1, it is characterized in that, further include:
    Step S8, by second high-definition pictureAs the first new high-definition picture
    After repeating step S3-S7 by M times, the 3rd high-definition picture is obtained
    Using the bicubic interpolation algorithm to the 3rd high-definition pictureFuzzy down-sampling is carried out, generates initial target High-definition picture
  3. 3. according to the method described in claim 2, it is characterized in that, further include:
    Step S9, to the initial target high-definition pictureAlternating minimization algorithm meter is used with the low-resolution image y Calculate mathematical model:
    s.t.hf=hr,
    Wherein, the initial value of the x in above-mentioned mathematical model is initial target high-definition pictureUnder degenerate matrix H represents fuzzy Sample operator, λ1And λ2Represent regularization parameter, αiIt is the high resolution graphics photo x of target high-resolution image xiSparse system Number, α αiSet, βiIt is αiNon-local mean in sparse coding domain,Represent the sparse coefficient matrix α of all splicings and surpass The product of complete dictionary φ,Represent gradient operation symbol, f is transforming function transformation function, hrIt is the reference Nogata of target high-resolution image Figure, hfIt is the histogram of transforming function transformation function f.
  4. It is 4. according to the method described in claim 3, it is characterized in that, described to the initial target high-definition pictureAnd institute Low-resolution image y is stated to specifically include using alternating minimization algorithm calculating mathematical model:
    Step S10, super complete dictionary is obtained using K mean cluster algorithm and Principal Component Analysis Algorithm;
    Step S11, remains unchanged algorithm according to histogram of gradients and updates the transforming function transformation function f;
    Step S12, updates the initial target high-definition picture according to the super complete dictionary and the transforming function transformation function f.
  5. 5. according to the method described in claim 4, it is characterized in that, obtained using K mean cluster algorithm and Principal Component Analysis Algorithm Super complete dictionary is taken, is specifically included:
    According to size randomly select the high resolution graphics photos of K initial target high-definition pictures as K it is a at the beginning of Begin cluster;
    According to the distance between the high resolution graphics photo and the K initial cluster center, by the initial target high score All high resolution graphics photos that resolution image is divided into are divided into corresponding initial clustering;
    To each initial clustering using the corresponding sub- dictionary of Principal Component Analysis training based on singular value decomposition;
    The K corresponding K sub- dictionary composition of the initial clustering super complete dictionaries.
  6. 6. according to the method described in claim 4, it is characterized in that, remaining unchanged algorithm according to histogram of gradients updates the change Exchange the letters number f, specifically includes:
    Fuzzy up-sampling is carried out to the low-resolution image y, obtains low-resolution image z;
    The target high-resolution image x and the low-resolution image z meet following condition:Z=B*x, wherein B are fuzzy Core;
    Gradient is asked to z=B*x both sides, thenWherein b0And biFuzzy core B is represented respectively Center coefficient and its surrounding's neighbour's coefficient,Represent the gradient image of target high-resolution image x,Represent described low The gradient image of image in different resolution z,Represent the gradient image of the high resolution graphics photo;
    OrderIfIt is similar to normal distribution, then
    Pass through solving-optimizing problems.t.hf=hrTo update transforming function transformation function f;
    Wherein hrRepresent the terraced histogram of reference of target high-resolution image x, hzRepresent that the gradient of the low-resolution image z is straight Fang Tu, hx1It is the discrete form of the probability density function of stochastic variable x1, hx2Be I.i.d. random variables x2 probability it is close The discrete form of function is spent,It is convolution operation symbol.
  7. It is 7. according to the method described in claim 4, it is characterized in that, described according to the super complete dictionary and the transforming function transformation function F updates the initial target high-definition picture, specifically includes:
    According to formulaDetermine x(t+1/2), wherein x(t)Represent the The target high-resolution Image estimation value of t iteration, x(t+1/2)Represent the target high-resolution Image estimation of the t+1/2 times iteration Value, δ is constant,Represent x(t)Gradient map;
    According toDetermineWhereinRepresent the high-definition picture of the t+1/2 times iteration Piece xiSparse coefficient,Represent the high resolution graphics photo x of the t times iterationiThe corresponding sub- dictionary of place initial clustering, RiTable Show from initial target high-definition pictureHigh resolution graphics photo x is obtained at the i of positioniMatrix;
    According to sparse coefficientWith Determine the high resolution graphics photo x of the t+1 times iterationiSparse coefficientωiJ-th of component ωijMeet:Wherein h represents the control parameter for adjusting the rate of decay, and W represents normalization factor, Represent high resolution graphics photo xiJ-th of most like image sheet in corresponding most like image sheet group, Sλ/cRepresent soft-threshold letter Number, c represent regularization parameter;
    According to formulaDetermine x(t+1), wherein x(t+1)Represent t+1 The target high-resolution Image estimation value of secondary iteration, φ(t+1)Represent x(t+1)Corresponding super complete dictionary.
  8. 8. according to claim 4-7 any one of them methods, it is characterised in that further include:
    Step S10-S12 is repeated, acquisition convergence solution is final goal high-definition picture x';
    The final goal high-definition picture is restored using plural impact filtering formula, wherein the plural number impact filter Ripple formula is:
    <mrow> <msup> <mi>x</mi> <mrow> <mo>&amp;prime;</mo> <mo>&amp;prime;</mo> </mrow> </msup> <mo>=</mo> <mo>-</mo> <mfrac> <mn>2</mn> <mi>&amp;pi;</mi> </mfrac> <mi>a</mi> <mi>r</mi> <mi>c</mi> <mi>t</mi> <mi>a</mi> <mi>n</mi> <mrow> <mo>(</mo> <mi>a</mi> <mi> </mi> <mi>Im</mi> <mo>(</mo> <mfrac> <msup> <mi>x</mi> <mo>&amp;prime;</mo> </msup> <mi>&amp;theta;</mi> </mfrac> <mo>)</mo> <mo>)</mo> </mrow> <mo>|</mo> <mrow> <mo>&amp;dtri;</mo> <msup> <mi>x</mi> <mo>&amp;prime;</mo> </msup> </mrow> <mo>|</mo> <mo>+</mo> <msubsup> <mi>&amp;tau;x</mi> <mrow> <mi>&amp;eta;</mi> <mi>&amp;eta;</mi> </mrow> <mo>&amp;prime;</mo> </msubsup> <mo>+</mo> <mover> <mi>&amp;tau;</mi> <mo>&amp;OverBar;</mo> </mover> <msubsup> <mi>x</mi> <mrow> <mi>&amp;xi;</mi> <mi>&amp;xi;</mi> </mrow> <mo>&amp;prime;</mo> </msubsup> </mrow>
    Wherein, x ' expressions final goal high-definition picture, x " represent the final goal high-definition picture after restoring,Table Show the gradient map of x', η and ξ represent the gradient direction of image, and Im () represents extraction imaginary part, and a represents to be used to control image sharpness Adjusting parameter, τ=| τ | exp (i θ) is complex scalar coefficient,It is real number scalar factor.
  9. A kind of 9. super-resolution image reconstruction device, it is characterised in that including:
    Generation module, for using the low-resolution image y of input as the first high-definition pictureAccording to first high score Resolution imageCarry out n times and obscure down-sampling, generation high resolution image data storehouse Dx
    The generation module, is additionally operable to first high-definition pictureUsing bicubic interpolation algorithm adopt under obscuring Sample and then carry out fuzzy up-sampling and obtain the first low-resolution imageFor first low-resolution imageCarry out N times obscure down-sampling, generation low resolution image data storehouse Dz
    Division module, for using the bicubic interpolation algorithm by first high-definition pictureObtained after S times of amplification Second low-resolution imageBy second low-resolution imageIt is divided at least one low-resolution image piece;
    Acquisition module, for using approximate KNN searching algorithm in the low resolution figure to each low-resolution image piece As database DzObtain the corresponding most like image sheet group of low resolution;
    Computing module, for calculating weight coefficient using Ridge Regression Method to the most like image sheet group of the low resolution;
    Determining module, for determining high resolution graphics photo according to the weight coefficient and the most like image sheet group of high-resolution;
    The determining module, is additionally operable to determine the second high resolution graphics using weighted mean method to the high resolution graphics photo PictureAnd by second low-resolution imageIt is added to the database DzIn, by second high-definition picture It is added to the database DxIn.
  10. 10. device according to claim 9, it is characterised in that further include:
    The acquisition module, is additionally operable to obtain the 3rd high-definition picture
    The generation module, is also used using the bicubic interpolation algorithm to the 3rd high-definition pictureCarry out under obscuring Sampling, generates initial target high-definition picture
  11. 11. device according to claim 10, it is characterised in that further include:
    The computing module, is additionally operable to the initial target high-definition pictureWith the low-resolution image y using alternating Minimize algorithm and calculate mathematical model:
    s.t.hf=hr,
    Wherein, the initial value of the x in above-mentioned mathematical model is initial target high-definition pictureUnder degenerate matrix H represents fuzzy Sample operator, λ1And λ2Represent regularization parameter, αiIt is the high resolution graphics photo x of target high-resolution image xiSparse system Number, α αiSet, βiIt is αiNon-local mean in sparse coding domain,Represent the sparse coefficient matrix α of all splicings and surpass The product of complete dictionary φ,Represent gradient operation symbol, f is transforming function transformation function, hrIt is the reference Nogata of target high-resolution image Figure, hfIt is the histogram of transforming function transformation function f.
  12. 12. according to the devices described in claim 11, it is characterised in that further include:Update module;
    The acquisition module, is additionally operable to obtain super complete dictionary using K mean cluster algorithm and Principal Component Analysis Algorithm;
    The update module, updates the transforming function transformation function f for remaining unchanged algorithm according to histogram of gradients;
    The update module, updates the initial target high-resolution always according to the super complete dictionary and the transforming function transformation function f Image.
  13. 13. according to the devices described in claim 11, it is characterised in that the acquisition module is specifically used for:
    According to size randomly select the high resolution graphics photos of K target high-resolution images as K it is a at the beginning of Begin cluster;
    According to the distance between the high resolution graphics photo and the K initial cluster center, by the target high-resolution All high resolution graphics photos that image is divided into are divided into corresponding initial clustering;
    To each initial clustering using the corresponding sub- dictionary of Principal Component Analysis training based on singular value decomposition;
    The K corresponding K sub- dictionary composition of the initial clustering super complete dictionaries.
  14. 14. device according to claim 12, it is characterised in that the update module is specifically used for:
    Fuzzy up-sampling is carried out to the low-resolution image y, obtains low-resolution image z;
    The target high-resolution image x and the low-resolution image z meet following condition:Z=B*x, wherein B are fuzzy Core;
    Gradient is asked to z=B*x both sides, thenWherein b0And biFuzzy core B is represented respectively Center coefficient and its surrounding's neighbour's coefficient,Represent the gradient image of target high-resolution image x,Represent described low The gradient image of image in different resolution z,Represent the gradient image of the high resolution graphics photo;
    OrderIfIt is similar to normal distribution, then
    Pass through solving-optimizing problems.t.hf=hrTo update transforming function transformation function f;
    Wherein hrRepresent the terraced histogram of reference of target high-resolution image x, hzRepresent that the gradient of the low-resolution image z is straight Fang Tu, hx1It is the discrete form of the probability density function of stochastic variable x1, hx2Be I.i.d. random variables x2 probability it is close The discrete form of function is spent,It is convolution operation symbol.
  15. 15. device according to claim 12, it is characterised in that the update module is specifically used for:
    According to formulaDetermine x(t+1/2), wherein x(t)Represent The target high-resolution Image estimation value of the t times iteration, x(t+1/2)Represent that the target high-resolution image of the t+1/2 times iteration is estimated Evaluation, δ are constant,Represent x(t)Gradient map;
    According toDetermineWhereinRepresent the high-definition picture of the t+1/2 times iteration Piece xiSparse coefficient,Represent the high resolution graphics photo x of the t times iterationiThe corresponding sub- dictionary of place initial clustering, RiTable Show from initial target high-definition pictureHigh resolution graphics photo x is obtained at the i of positioniMatrix;
    According to sparse coefficientWith Determine the high resolution graphics photo x of the t+1 times iterationiSparse coefficientωiJ-th of component ωijMeet:Wherein h represents the control parameter for adjusting the rate of decay, and W represents normalization factor, Represent high resolution graphics photo xiJ-th of most like image sheet in corresponding most like image sheet group, Sλ/cRepresent soft-threshold letter Number, c represent regularization parameter;
    According to formulaDetermine x(t+1), wherein x(t+1)Represent t+1 The target high-resolution Image estimation value of secondary iteration, φ(t+1)Represent x(t+1)Corresponding super complete dictionary.
  16. 16. according to claim 9-15 any one of them devices, it is characterised in that further include:Filter module;
    It is final goal high-definition picture x' that the acquisition module, which obtains convergence solution,;
    The filter module, for being restored using plural impact filtering formula to the final goal high-definition picture, Wherein described plural impact filtering formula is:
    <mrow> <msup> <mi>x</mi> <mrow> <mo>&amp;prime;</mo> <mo>&amp;prime;</mo> </mrow> </msup> <mo>=</mo> <mo>-</mo> <mfrac> <mn>2</mn> <mi>&amp;pi;</mi> </mfrac> <mi>a</mi> <mi>r</mi> <mi>c</mi> <mi>t</mi> <mi>a</mi> <mi>n</mi> <mrow> <mo>(</mo> <mi>a</mi> <mi> </mi> <mi>Im</mi> <mo>(</mo> <mfrac> <msup> <mi>x</mi> <mo>&amp;prime;</mo> </msup> <mi>&amp;theta;</mi> </mfrac> <mo>)</mo> <mo>)</mo> </mrow> <mo>|</mo> <mrow> <mo>&amp;dtri;</mo> <msup> <mi>x</mi> <mo>&amp;prime;</mo> </msup> </mrow> <mo>|</mo> <mo>+</mo> <msubsup> <mi>&amp;tau;x</mi> <mrow> <mi>&amp;eta;</mi> <mi>&amp;eta;</mi> </mrow> <mo>&amp;prime;</mo> </msubsup> <mo>+</mo> <mover> <mi>&amp;tau;</mi> <mo>&amp;OverBar;</mo> </mover> <msubsup> <mi>x</mi> <mrow> <mi>&amp;xi;</mi> <mi>&amp;xi;</mi> </mrow> <mo>&amp;prime;</mo> </msubsup> </mrow>
    Wherein, x ' expressions final goal high-definition picture, x " represent the final goal high-definition picture after restoring,Table Show the gradient map of x', η and ξ represent the gradient direction of image, and Im () represents extraction imaginary part, and a represents to be used to control image sharpness Adjusting parameter, τ=| τ | exp (i θ) is complex scalar coefficient,It is real number scalar factor.
CN201410532272.6A 2014-10-10 2014-10-10 Super-resolution image reconstruction method and device Expired - Fee Related CN105488776B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201410532272.6A CN105488776B (en) 2014-10-10 2014-10-10 Super-resolution image reconstruction method and device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201410532272.6A CN105488776B (en) 2014-10-10 2014-10-10 Super-resolution image reconstruction method and device

Publications (2)

Publication Number Publication Date
CN105488776A CN105488776A (en) 2016-04-13
CN105488776B true CN105488776B (en) 2018-05-08

Family

ID=55675742

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201410532272.6A Expired - Fee Related CN105488776B (en) 2014-10-10 2014-10-10 Super-resolution image reconstruction method and device

Country Status (1)

Country Link
CN (1) CN105488776B (en)

Families Citing this family (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106204445A (en) * 2016-06-30 2016-12-07 北京大学 Image/video super-resolution method based on structure tensor total variation
CN106339984B (en) * 2016-08-27 2019-09-13 中国石油大学(华东) Distributed image ultra-resolution method based on K mean value driving convolutional neural networks
CN106851321A (en) * 2017-01-15 2017-06-13 四川精目科技有限公司 A kind of least square regression high speed camera compresses image rebuilding method
CN107239781B (en) * 2017-05-03 2020-07-28 北京理工大学 Hyperspectral reflectivity reconstruction method based on RGB image
CN107680037B (en) * 2017-09-12 2020-09-29 河南大学 Improved face super-resolution reconstruction method based on nearest characteristic line manifold learning
CN108416734A (en) * 2018-02-08 2018-08-17 西北大学 Text image super resolution ratio reconstruction method and device based on edge driving
CN109978785B (en) * 2019-03-22 2020-11-13 中南民族大学 Image super-resolution reconstruction system and method based on multi-level recursive feature fusion
CN110148091A (en) * 2019-04-10 2019-08-20 深圳市未来媒体技术研究院 Neural network model and image super-resolution method based on non local attention mechanism
CN111986078B (en) * 2019-05-21 2023-02-10 四川大学 Multi-scale core CT image fusion reconstruction method based on guide data
CN110363235B (en) * 2019-06-29 2021-08-06 苏州浪潮智能科技有限公司 High-resolution image matching method and system
WO2022036556A1 (en) * 2020-08-18 2022-02-24 香港中文大学(深圳) Image processing method and apparatus, computer device, and storage medium
CN112767427A (en) * 2021-01-19 2021-05-07 西安邮电大学 Low-resolution image recognition algorithm for compensating edge information
CN112950476A (en) * 2021-03-12 2021-06-11 广州冠图视觉科技有限公司 Method for improving resolution and definition of picture
CN115829842B (en) * 2023-01-05 2023-04-25 武汉图科智能科技有限公司 Device for realizing super-resolution reconstruction of picture based on FPGA

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102136144A (en) * 2011-04-11 2011-07-27 北京大学 Image registration reliability model and reconstruction method of super-resolution image
CN102354394A (en) * 2011-09-22 2012-02-15 中国科学院深圳先进技术研究院 Image super-resolution method and system
CN102968766A (en) * 2012-11-23 2013-03-13 上海交通大学 Dictionary database-based adaptive image super-resolution reconstruction method
CN103871041A (en) * 2014-03-21 2014-06-18 上海交通大学 Image super-resolution reconstruction method based on cognitive regularization parameters

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2009087641A2 (en) * 2008-01-10 2009-07-16 Ramot At Tel-Aviv University Ltd. System and method for real-time super-resolution

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102136144A (en) * 2011-04-11 2011-07-27 北京大学 Image registration reliability model and reconstruction method of super-resolution image
CN102354394A (en) * 2011-09-22 2012-02-15 中国科学院深圳先进技术研究院 Image super-resolution method and system
CN102968766A (en) * 2012-11-23 2013-03-13 上海交通大学 Dictionary database-based adaptive image super-resolution reconstruction method
CN103871041A (en) * 2014-03-21 2014-06-18 上海交通大学 Image super-resolution reconstruction method based on cognitive regularization parameters

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
Anchored Neighborhood Regression for Fast Example-Based Super-Resolution;Radu Timofte 等;《2013 IEEE International Conference on Computer Vision(ICCV)》;20140303;1920-1927 *
Image Super-Resolution Via Sparse Representation;Jianchao Yang 等;《IEEE TRANSACTIONS ON IMAGE PROCESSING》;20101130;第19卷(第11期);2861-2873 *
基于显著性稀疏表示的图像超分辨率算法;白蔚 等;《中国科技论文》;20140131;第9卷(第1期);103-107 *

Also Published As

Publication number Publication date
CN105488776A (en) 2016-04-13

Similar Documents

Publication Publication Date Title
CN105488776B (en) Super-resolution image reconstruction method and device
Xiao et al. Satellite video super-resolution via multiscale deformable convolution alignment and temporal grouping projection
Yang et al. DRFN: Deep recurrent fusion network for single-image super-resolution with large factors
CN101950365B (en) Multi-task super-resolution image reconstruction method based on KSVD dictionary learning
Sun et al. Lightweight image super-resolution via weighted multi-scale residual network
CN109146788A (en) Super-resolution image reconstruction method and device based on deep learning
CN105590304B (en) Super-resolution image reconstruction method and device
CN111369487A (en) Hyperspectral and multispectral image fusion method, system and medium
CN104599242A (en) Multi-scale non-local regularization blurring kernel estimation method
CN106408550A (en) Improved self-adaptive multi-dictionary learning image super-resolution reconstruction method
Li et al. A lightweight multi-scale channel attention network for image super-resolution
CN111861886B (en) Image super-resolution reconstruction method based on multi-scale feedback network
CN114418853B (en) Image super-resolution optimization method, medium and equipment based on similar image retrieval
CN111951167A (en) Super-resolution image reconstruction method, super-resolution image reconstruction device, computer equipment and storage medium
CN113421187B (en) Super-resolution reconstruction method, system, storage medium and equipment
Xu et al. AutoSegNet: An automated neural network for image segmentation
CN113469884A (en) Video super-resolution method, system, equipment and storage medium based on data simulation
CN113888491A (en) Multilevel hyperspectral image progressive and hyper-resolution method and system based on non-local features
Xia et al. Meta-learning-based degradation representation for blind super-resolution
Shen et al. RSHAN: Image super-resolution network based on residual separation hybrid attention module
CN113723472A (en) Image classification method based on dynamic filtering equal-variation convolution network model
CN116797456A (en) Image super-resolution reconstruction method, system, device and storage medium
CN116188272B (en) Two-stage depth network image super-resolution reconstruction method suitable for multiple fuzzy cores
CN111311732A (en) 3D human body grid obtaining method and device
CN114155560B (en) Light weight method of high-resolution human body posture estimation model based on space dimension reduction

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant
TR01 Transfer of patent right

Effective date of registration: 20220621

Address after: 100871 No. 5, the Summer Palace Road, Beijing, Haidian District

Patentee after: Peking University

Patentee after: New founder holdings development Co.,Ltd.

Patentee after: BEIJING FOUNDER ELECTRONICS Co.,Ltd.

Address before: 100871 No. 5, the Summer Palace Road, Beijing, Haidian District

Patentee before: Peking University

Patentee before: PEKING UNIVERSITY FOUNDER GROUP Co.,Ltd.

Patentee before: BEIJING FOUNDER ELECTRONICS Co.,Ltd.

TR01 Transfer of patent right
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20180508

CF01 Termination of patent right due to non-payment of annual fee