Specific implementation mode
In conjunction with following application scenarios, the invention will be further described.
Referring to Fig. 1, including finger print acquisition module 1, D/A converter module 2, fingerprint image processing module 3, fingerprint database
Module 4 and result verification module 5,1 rear of the finger print acquisition module connects the D/A converter module 2, for acquiring target
The infrared image and ultraviolet image of fingerprint;The D/A converter module 2 is used for infrared image and ultraviolet image to target fingerprint
Digital-to-analogue conversion is carried out respectively;The fingerprint image processing module 3 is used to carry out the infrared image of target fingerprint with ultraviolet image
Denoising, decomposition and synthesis processing, obtain target fingerprint image;The fingerprint image of standard is stored in the fingerprint database module 4
Picture;The result verification module 5 is connect with the fingerprint image processing module 3 and the fingerprint database module 4, is used for mesh
The fingerprint image for marking fingerprint image and standard carries out contrast verification, obtains fingerprint authentication as a result, and being shown to result.
Preferably, it when the finger print acquisition module is acquired the infrared image and ultraviolet image of target fingerprint, uses
Infrared COMS imaging lens are acquired the infrared image of target fingerprint, using ultraviolet CCD imaging lens to target fingerprint
Ultraviolet image is acquired, and LED exciter components are connected in front of ultraviolet CCD imaging lens, and rear is connected with ultraviolet image enhancing
Device, finally connects infrared COMS imaging lens, all camera lens light path coaxials and is placed in parallel.
Preferably, the infrared COMS imaging lens and ultraviolet CCD imaging lens are all double-colored integrated structure.
The above embodiment of the present invention merges the infrared image of target fingerprint with ultraviolet image, after fusion
Fingerprint image carries out fingerprint recognition, is greatly improved the accuracy of fingerprint recognition.
Preferably, as shown in Fig. 2, the fingerprint image processing module includes fingerprint image preprocessing submodule, fingerprint image
As resolution process submodule and fingerprint image merge submodule;The fingerprint image preprocessing submodule is by the infrared figure with noise
Picture and ultraviolet image carry out wavelet transform process, obtain corresponding wavelet coefficient, the wavelet coefficient obtained at this time includes noiseless
Then wavelet coefficient and noise wavelet coefficients utilize the infrared image of improved wavelet threshold function pair target fingerprint and ultraviolet
Image carries out denoising, specially:
(1) obtained wavelet coefficient is carried out by thresholding processing using improved threshold function table, to filter out noise wavelet system
Number, obtain noiseless wavelet coefficient, the improved threshold function table used for:
In formula,Indicate that noiseless wavelet coefficient, ψ are that the infrared image with noise and ultraviolet image carry out at wavelet transformation
The wavelet coefficient obtained after reason, sgn () are sign function, and i is the variable of sign function, and p and q are adjustable parameter, and υ is small echo
Coefficient threshold, ε are that noise criteria is poor;
As p=0 or q=∞, this improved threshold function table is hard threshold function, and as p=1 and q=1, this is improved
Threshold function table is soft-threshold function;
(2) noiseless wavelet coefficient is obtained after being handled using thresholding carries out the infrared image to target fingerprint and ultraviolet figure
As being reconstructed, noiseless infrared image and noiseless ultraviolet image are obtained.
The above embodiment of the present invention passes through the infrared image and ultraviolet image of fingerprint image by improved threshold function table
Band noise wavelet coefficients in the wavelet coefficient obtained after wavelet transform process are filtered out, then using filter out band noise wavelet
Wavelet coefficient after coefficient carries out image reconstruction, obtains side noiseless infrared image and ultraviolet image, carries out fingerprint image and locates in advance
Reason filters out the noise in fingerprint image, to obtain the target fingerprint image graph of high quality in target fingerprint image co-registration
Picture, and improved threshold function table can by adjust p and q value, make improved threshold function table between soft, hard threshold function it
Between, flexibility when enhancing filters out wavelet coefficient.
Preferably, the fingerprint image resolution process submodule is first to passing through the fingerprint image preprocessing resume module
Afterwards, the noiseless infrared image X obtained1With noiseless ultraviolet image X2It is carried out respectively using non-downsampling Contourlet conversion
Resolution process obtains a respective low frequency sub-band coefficient and a series of high-frequency sub-band coefficient, i.e., With
X1 Low(j, k) and X2 Low(j, k) indicates noiseless infrared image X respectively1With noiseless ultraviolet image X2At pixel (j, k)
Low frequency sub-band coefficient,WithIndicate noiseless infrared image X1With the ultraviolet figure of noiseless
As X2The high-frequency sub-band coefficient in n-th of direction of m-th of scale at pixel (j, k), M are scale parameter, and m is indicated m-th
Scale, n are n-th of direction, nmFor the direction number under m-th of scale;
Then the sub-band coefficients and 4 pixels of surrounding pixel at (j, k) obtained after NSCT carries out resolution process
The subband coefficient values of point are compared, with the work of two width noise-free picture pixel of self-defined liveness calculation formula node-by-node algorithm
Jerk utilizes noiseless infrared image X1With noiseless ultraviolet image X2High-frequency sub-band coefficient carry out liveness calculating, obtain picture
The high-frequency sub-band liveness of vegetarian refreshments (j, k), self-defined liveness calculation formula are:
In formula,WithNoiseless infrared image X is indicated respectively1It is ultraviolet with noiseless
Image X2In at (j, k) n-th of direction of m-th of scale of pixel high-frequency sub-band liveness,WithIndicate noiseless infrared image X1With noiseless ultraviolet image X2M-th of scale, n-th of side at (j, k)
To high-frequency sub-band coefficient, Table respectively
Show noiseless infrared image X1With noiseless ultraviolet image X2It is adjacent with the up, down, left and right four directions of pixel at (j, k)
The high-frequency sub-band coefficient in m-th of scale, n-th of direction of pixel;
Similarly, high-frequency sub-band coefficient is changed into low frequency sub-band coefficient, using self-defined liveness calculation formula, to two width
The liveness of the low frequency sub-band of noise-free picture is calculated, and noiseless infrared image X is obtained1With noiseless ultraviolet image X2
The liveness W of the low frequency sub-band of pixel at (j, k)1 Low(j, k) and W2 Low(j,k)。
The above embodiment of the present invention goes out noiseless infrared image and nothing by self-defined liveness calculation formula node-by-node algorithm
The liveness of pixel in noise ultraviolet image reflects that the readability of pixel, the liveness of pixel are got over liveness
High then the point clarity is higher, when according to liveness to infrared image and UV Image Fusion, is conducive to choose and arrives clarity
Higher pixel, obtain quality is higher, more merged comprising minutia after target fingerprint image.
Preferably, the fingerprint image merges submodule first to noiseless infrared image X1With noiseless ultraviolet image X2
Liveness at point (j, k) is compared, and corresponding liveness comparison result is obtained, according to liveness comparison result, antithetical phrase
Band coefficient carries out value again, obtains new high-frequency sub-band coefficient and new low frequency sub-band coefficient, and new sub-band coefficients are made
For the sub-band coefficients of the target fingerprint image after fusion, specially:
In formula, X (j, k) is target fingerprint image after the fusion sub-band coefficients after value again at the point (j, k), X1
(j, k) and X2(j, k) is respectively noiseless infrared image X1With noiseless ultraviolet image X2Sub-band coefficients at point (j, k), W1
(j, k) and W2(j, k) is respectively noiseless infrared image X1With noiseless ultraviolet image X2In at (j, k) pixel liveness,
W1(j, k) includes W1 Low(j, k) andW2(j, k) includes W2 Low(j, k) andX1(j,
K) include X1 Low(j, k) andX2(j, k) includes X2 Low(j, k) andWork as X1(j, k)=
X1 LowWhen (j, k), X2(j, k)=X2 Low(j, k), W1(j, k)=W1 Low(j, k), W2(j, k)=W2 Low(j, k), whenWhen, To adjust threshold value,It is set as 0.5, X1 Low(j, k) and X2 Low(j, k) indicates the infrared figure of noiseless respectively
As X1With noiseless ultraviolet image X2Low frequency sub-band coefficient at pixel (j, k),WithIndicate noiseless infrared image X1With noiseless ultraviolet image X2M-th of scale at pixel (j, k)
N-th of direction high-frequency sub-band coefficient, J and K indicate the width and height of two width noise-free pictures respectively;
Using new high-frequency sub-band coefficient and new low frequency sub-band coefficient as the high-frequency sub-band coefficient of composograph with it is low
Frequency sub-band coefficients, by NSCT inverse transformation reconstructed images, the target fingerprint image after being merged, and exported.
The above embodiment of the present invention, to noiseless infrared image and noiseless ultraviolet image pixel liveness size ratio
Compared with, according to comparison result, different values is taken to the target fingerprint Image Sub-Band coefficient after fusion, be conducive to noise infrared image and
The details of noiseless ultraviolet image is complementary so that and the target fingerprint image after fusion can include the minutia of two images,
When carrying out fingerprint recognition verification, accuracy of identification is greatly improved.
Finally it should be noted that the above embodiments are merely illustrative of the technical solutions of the present invention, rather than the present invention is protected
The limitation of range is protected, although being explained in detail to the present invention with reference to preferred embodiment, those skilled in the art answer
Work as understanding, technical scheme of the present invention can be modified or replaced equivalently, without departing from the reality of technical solution of the present invention
Matter and range.