CN1564503A - Signal hiding encryption/deciphering method and appts. based on virtual holographic series - Google Patents

Abstract

The method uses parallel algorithm and hardware. Encryption includes steps: calculating weighted summation of discrete Fresnel diffraction transform on hologram plane in virtual class from information plane and random template; digital hologram reconstruction is carried out by using 'spectrum operation'. Decryption includes steps: calculating contribution of random template in encryption procedure by using corresponding decryption parameter, then subtracting the said contribution from cryptograph to obtain light intensity on reconstruction plane from information plane so as to obtain original information image. The method is suitable to speech information processing. The device includes PC, DSP and dedicated programmable IC. System is in maser/slave mode, or embedded type. Advantages are: non-linear high security classification and flexibility.

Description

Information hiding method for encryption/decryption and device based on virtual class holography

Technical field

The present invention relates to a kind of Information hiding method for encryption/decryption and device, belong to field of information security technology based on virtual class holography.

Background technology

After entering the information age, information security issue becomes the focus that people pay close attention to.Data encryption technology is widely used in many key areas such as commerce is maintained secrecy, military communication.But the domestic cryptographic algorithm that adopts mostly is the low-intensity cryptographic algorithm that abroad will eliminate at present.The unsafe factor that is brought has become a major issue of current obstruction economic development and threat national security thus.

Based on the data encryption technology of optical information processing is to begin a kind of new " non-mathematics " data encryption technology of starting to walk to develop in recent years in the world.Different with electronic processors, optical system has the ability that inherent parallel data is handled, and can side by side be propagated and handle as each pixel in the width of cloth two dimensional image in optical system.When carrying out the bulk information processing, the parallel processing capability of optical system clearly occupies absolute advantage.Simultaneously, the optical encryption device has the more freedom degree than Electronic Coding device, and information can be hidden in a plurality of degrees of freedom space---as phase place, wavelength, spatial frequency and polarization state of light etc.

But at present the full optical system of development and photoelectricity blended data encryption system all form as yet can practical application system.Main cause be compare with the encrypted electronic data processor that the optical component volume of propagating based on free space is big, cost is very high, troublesome poeration, poor stability and processing accuracy be low.System with such optical component structure is difficult to use in real data is encrypted.

We once disclosed a kind of Information hiding method for encryption/decryption and device based on virtual image in CN1474283A.The data ciphering method that this documents adopts comes down to based on the optical imagery process, and this method is finished high-intensity data encryption by Digital Simulation lens imaging process.

Optical holographic is the another kind of physical process that is different from lens imaging fully.Optical holographic is the technology of (comprise amplitude with position mutually) before utilizing principle of interference to come marking wave, is divided into record and reproduces for two steps.When recorded hologram, except the thing light that will write down, also must introduce the reference light identical with the thing optical wavelength, so just obtain interference fringe in the overlapping region of thing light and reference light, hologram record be exactly this interference fringe, it has promptly embodied the distribution of amplitudes of thing light, has also embodied its position and has distributed mutually.Optical holographic is compared with lens imaging, the characteristic of many codings.

The implication of " virtual class holography " is to finish in the process of information encryption at the Digital Simulation optical holographic, be that information plane and random mask plane are considered as the two-layer of an object, utilize the directly intensity of the two coherent superposition of record on virtual class hologram plane of discrete fresnel diffraction conversion, wherein comprised amplitude and phase information; Utilize " spectrum operation " method to carry out digital hologram on the plane, Virtual Space and rebuild afterwards again.This process is not owing to introduce " reference light " of ordinary meaning, but with the speckle field of the fresnel diffraction of random mask as reference light, so be not real optical holographic process, thereby be called " class holography ".

The technical literature that can contrast has following five pieces:

[1]X.Peng，Z.Y.Cui，and?T.Tan：Information?encryption?with?virtual-optics?imaging?system，Optics?Communications，2002，212：235-245

[2]X.Peng，Z.Y.Cui，and?T.Tan：Image?encryption?with?virtual?optics， Proc.SPIE?4929，2002，96-104.(Invited?Paper)

[3]P.Refregier，and?B.Javidi：Optical?image?encryption?based?on?input?and?Fourier?planerandom?encoding，Optics?Letters，1995，20(7)：767-769

[4] patent of invention: publication number CN1474283A

[5]US?Patents：6,002,773；5,903,648

Summary of the invention

The object of the present invention is to provide a kind of Information hiding method for encryption/decryption and device based on virtual class holography.Described method has the advantages that ciphering process is non-linear, the enciphering/deciphering degree of freedom is big, level of security is high; Described device has the high and adaptable characteristics of the flexibility of use.

For achieving the above object, the present invention is realized by following technical proposals.Use the electronic installation and the software simulation optical holographic process of parallel hardware and algorithm to hide the method for enciphering/deciphering, it is characterized in that specific practice is comprising image and voice messaging:

Encrypting the encrypting step of holding for image information:

1) based on information plane and random mask are considered as the two-layer of an object, do not introduce under the situation of " reference light " of ordinary meaning, utilize the method for numeral to simulate the record and the reconstruction of the virtual class holography of this two-layer object.

2) computing information plane and random mask branch are clipped to the weighted sum of the discrete fresnel diffraction conversion of virtual class hologram plane, as the record result on the virtual class hologram plane.

3) adopt the method for " spectrum operation " to carry out the digital hologram reconstruction on the plane, Virtual Space, obtain ciphertext.The coding of random mask itself, wavelength X, the discrete fresnel diffraction of random mask is apart from d _m, digital hologram is rebuild distance z, and they all are key parameters of record and process of reconstruction.

Image information after the encryption follows these steps to deciphering after communication line reaches decrypting end:

1) receives correct random mask information.

2) utilize corresponding deciphering parameter such as wavelength X, the discrete fresnel diffraction of random mask is apart from d _m, calculate the discrete fresnel diffraction conversion of random mask to virtual class hologram plane, obtain its COMPLEX AMPLITUDE on virtual class hologram plane.

Same reconstruction distance z is carried out the digital hologram reconstruction to the random mask plane when 3) adopting the method for " compose and operate " and utilizing with encryption, and should the distribution value deduct from ciphertext.

4) do the COMPLEX AMPLITUDE that inverse Fourier transform obtains information at the rebuilding plane place of information plane, obtain light intensity by complex amplitude and can recover the prime information image.

Enciphering/deciphering step for voice messaging:

Utilize software that speech data is read in the matrix, utilize array manipulation that its element is rearranged the matrix that makes it to become a N * N again, operate at encryption end and decrypting end enciphering/deciphering step according to above-mentioned image information then.

Realize the enciphering/deciphering device of said method, this device comprises the master-slave system that is made of general purpose PC and digital signal processor DSP, or comprises the embedded system of the disengaging PC isolated operation that is made of digital signal processor or programmable asic; And device is linked in sequence according to following, the input of device is connected with the output of communication system, the output of device directly is connected with communication line, when original communication system information transmitted is an analog signal, also between the input of enciphering/deciphering device and communication system, add mould/number conversion interface, between the output of enciphering/deciphering device and communication line, add the D/A translation interface.

The invention has the advantages that: (1) algorithm simulating optical holographic process is carried out enciphering/deciphering to information, and its physical background is very clear; (2) than the traditional data ciphering process the bigger degree of freedom is arranged, the level of security height.Such as, can select a wavelength design key arbitrarily in a certain spectral region, and not rely on physics light source (as laser) with specific wavelength; (3) ciphering process is non-linear, and level of confidentiality is improved; (4) system realizes encryption and decryption at numeric field, can eliminate the physical restriction of optics so fully, and the thought that optical data is encrypted can realize at an easy rate; (5) used digital signal processor or programmable asic, with the physical process of parallel information enciphering/deciphering in the electronically artificial intelligence optics, fast, the anti-external interference performance of enciphering/deciphering speed is strong; (6) can constitute embedded system, finish enciphering/deciphering in real time sensitive information.

Description of drawings:

Fig. 1 is the master-slave mode enciphering/deciphering device hardware block diagram that is made of general purpose PC and digital signal processor DSP.

Fig. 2 is the encryption/decryption algorithm principle schematic.

Fig. 3 is the embedded enciphering/deciphering apparatus structure block diagram that is made of array of digital signal processors.

Fig. 4 is the embedded enciphering/deciphering apparatus structure block diagram that is made of the field programmable gate array chip array.

Fig. 5 is the embedded enciphering/deciphering apparatus structure block diagram that the programmable logic device array by complexity constitutes.

Fig. 6 is the former figure of information.

Fig. 7 encrypts the random mask that uses.

Fig. 8 is the result after the former figure of information encrypts.

Fig. 9 is the former figure of information through correct deciphering.

101 is general purpose PCs among the figure, the 102nd, pci bus controller, 103, the 301st, digital signal processor DSP chip, the 104, the 401st, field programmable gate array chip, the 105th, power management chip, the 106th, memory chip, the 501st, complicated programmable logic device, 1 is information plane, 2 is random mask, 3 is virtual class hologram plane, and 4 is the Virtual Space arbitrary plane.

Embodiment

Below in conjunction with accompanying drawing embodiments of the present invention are done and to be explained.For ease of explanation, the master-slave mode enciphering/deciphering system that constitutes with general purpose PC and digital signal processor DSP is embodiment, and following description will concentrate on this embodiment and be elaborated.

Fig. 1 is the master-slave mode enciphering/deciphering device hardware block diagram that is made of general purpose PC and digital signal processor DSP.As main frame, the DSP subsystem is as slave with general purpose PC in this master-slave mode enciphering/deciphering system.Functions such as the encryption of the slave realization multimedia messages that employing DSP subsystem constitutes, deciphering, packing, encapsulation.DSP finishes the core enciphering and deciphering algorithm, and FPGA finishes the interruption controls of system reset control, power management, pci controller and dsp interface control, pci controller and DSP, the transmission time sequence control of data.Pci bus by PC between the host and slave processors is carried out information exchange.

Fig. 2 is the encryption/decryption algorithm principle schematic.The encryption/decryption algorithm that realizes among the present invention is that the coding of simulated optical holography and the process of decoding are come enciphered message.Consider a two-layer object, form, be respectively z with the distance of virtual class hologram plane 3 by information plane 1 and random mask 2 _oAnd z _PRCM, the distance between the two is Δ z, supposes that diffraction related in the virtual optics system all satisfies the Fresnel approximation condition.At first calculate the weighted sum that information plane and random mask plane branch are clipped to the discrete fresnel diffraction conversion of virtual class hologram plane, as the record result on the virtual class hologram plane.In this course, do not introduce the reference light in the holographic process of ordinary optical, so " the virtual class holography " of meaning.

We introduce an operator DFD[A, B, m, n; z _AB, λ] and the fresnel diffraction process of digital space is described, wherein, A is illustrated in two planes that separate in the space on the direction of propagation with B, and spacing is designated as z _ABλ represents virtual optical wavelength.By Fourier optics theory:

$\mathrm{DFD}[A,B,m,n;z_{\mathrm{AB}},\mathrm{\&lambda;}]=\mathrm{Cexp}\left[j\frac{\mathrm{\&pi;}}{{\mathrm{\&lambda;z}}_{\mathrm{AB}}}({\mathrm{<figure-callout\; id="2"\; label="m"\; filenames="A20041001905600102.png"\; state="\{\{state\}\}">m</figure-callout>}}^2{\mathrm{\&Delta;\&xi;}}^2+{\mathrm{<figure-callout\; id="2"\; label="n"\; filenames="A20041001905600102.png"\; state="\{\{state\}\}">n</figure-callout>}}^2{\mathrm{\&Delta;\&eta;}}^2)\right]$

$\&times;\underset{k=0}{\overset{N-1}{\mathrm{\&Sigma;}}}\underset{l=0}{\overset{N-1}{\mathrm{\&Sigma;}}}{U}_A(k,l)\exp \left[j\frac{\mathrm{\&pi;}}{{\mathrm{\&lambda;z}}_{\mathrm{AB}}}({\mathrm{<figure-callout\; id="2"\; label="k"\; filenames="A20041001905600102.png"\; state="\{\{state\}\}">k</figure-callout>}}^2{{\mathrm{\&Delta;x}}_{\mathrm{<figure-callout\; id="2"\; label="o"\; filenames="A20041001905600102.png"\; state="\{\{state\}\}">o</figure-callout>}}}^2+{\mathrm{<figure-callout\; id="2"\; label="l"\; filenames="A20041001905600102.png"\; state="\{\{state\}\}">l</figure-callout>}}^2{{\mathrm{\&Delta;y}}_o}^2)\right]---\left(1\right)$

$\&times;\exp [-\mathrm{<figure-callout\; id="2"\; label="j"\; filenames="A20041001905600102.png"\; state="\{\{state\}\}">j</figure-callout>}2\mathrm{\&pi;}(\frac{\mathrm{km}}{N}+\frac{\ln }{N})]$

Wherein, $C=\frac{{\mathrm{<figure-callout\; id="2"\; label="e\; j"\; filenames="A20041001905600102.png"\; state="\{\{state\}\}">e</figure-callout>}}^j}{\mathrm{j\&lambda;}{z}_{\mathrm{AB}}}$ It is a complex constant.

The calculating of discrete as can be seen from the above equation Fresnel conversion (DFD) can be by by plane information and second order factor $\exp \left[j\frac{\mathrm{\&pi;}}{{\mathrm{\&lambda;z}}_{\mathrm{AB}}}({\mathrm{<figure-callout\; id="2"\; label="k"\; filenames="A20041001905600102.png"\; state="\{\{state\}\}">k</figure-callout>}}^2{{\mathrm{\&Delta;<figure-callout\; id="2"\; label="x\; o"\; filenames="A20041001905600102.png"\; state="\{\{state\}\}">x</figure-callout>}}_o}^2+{\mathrm{<figure-callout\; id="2"\; label="l"\; filenames="A20041001905600102.png"\; state="\{\{state\}\}">l</figure-callout>}}^2{{\mathrm{\&Delta;y}}_o}^2)\right]$ Long-pending fast Fourier transform FFT realize.

Adopt a kind of being called the way of " spectrum operation " to carry out digital hologram at Virtual Space arbitrary plane 4 to the record result on the virtual class hologram plane and rebuild, can obtain the ciphertext that the complex amplitude form distributes, it can transmit by communication link.

" spectrum operation " is to be used for separating holographic a kind of numerical operation, and available following computing formula is represented:

${A(\mathrm{\&xi;},\mathrm{\&eta;})}_{z=\mathrm{di}}={A(\mathrm{\&xi;},\mathrm{\&eta;})}_{z=\mathrm{dk}}\exp [\mathrm{<figure-callout\; id="2"\; label="i"\; filenames="A20041001905600102.png"\; state="\{\{state\}\}">i</figure-callout>}2\mathrm{\&pi;}(d_i-d_k)\&times;{(\frac{1}{{\mathrm{\&lambda;}}^2}-{\mathrm{\&xi;}}^2-{\mathrm{\&eta;}}^2)}^{\frac{1}{2}}]$

Wherein, and A (ξ, η) _Z=diBe that object wave is at z=d _iThe spectrum distribution at place, plane, and A (ξ, η) _Z=dkBe that it is at z=d _kThe spectrum distribution at place.

Get virtual class hologram plane as reference plane (z=0 place), make spectrum distribution A on this plane (ξ, η) _Z=0=O (ξ, η).Then can be expressed as along the spectrum distribution on the z axle arbitrary plane:

${A(\mathrm{\&xi;},\mathrm{\&eta;})}_{z=d_i}=O(\mathrm{\&xi;},\mathrm{\&eta;})\exp \left[\mathrm{<figure-callout\; id="2"\; label="i"\; filenames="A20041001905600102.png"\; state="\{\{state\}\}">i</figure-callout>}2\mathrm{\&pi;}{d}_i{(\frac{1}{{\mathrm{\&lambda;}}^2}-{\mathrm{\&xi;}}^2-{\mathrm{\&eta;}}^2)}^{\frac{1}{2}}\right]$

The coding of ciphertext and random mask itself, wavelength X, the discrete fresnel diffraction of random mask is apart from d _m, it is relevant that digital hologram is rebuild distance z, therefore can utilize these parameters to design the multidimensional key of encryption system.

We can see in ciphering process from said process, because system has multidimensional key, this will make the unauthorized persons of not knowing correct key be difficult to decrypt prime information expressly.The aforementioned calculation method has good reproducibility, repeatability.What computing was introduced owing to " compose operation " in this encryption method simultaneously is non-linear, will make this method have the not available High Security Levels of linear encryption algorithm such as documents 4.The test result of two kinds of encryption method key spaces sees the following form.

At receiving terminal, the process that is decrypted comprises the following steps:

1) receives correct random mask information.

2) utilize corresponding deciphering parameter (key) to calculate the discrete fresnel diffraction conversion of random mask to virtual class hologram plane,

Obtain its COMPLEX AMPLITUDE on virtual class hologram plane.

3) method of same employing the " spectrum operation " is carried out the digital hologram reconstruction to the random mask plane, and should the distribution value deduct from ciphertext.

4) do the COMPLEX AMPLITUDE that inverse Fourier transform can obtain information at the reconstruction plane place of information plane, obtain light intensity by complex amplitude and can recover the prime information image.

For reaching the purpose of real-time processing, the present invention is in the process that algorithm is realized, utilize parallel hardware (Parallel DSP), design parallel processing algorithm structure and software, improve the real-time of encryption system greatly, remedied the advantage of the Optical Parallel processing of adopting the Electronic Coding means fully and losing to a certain extent.

Fig. 3 is another embodiment of the present invention.In this embodiment, array of digital signal processors is constituting by individual digit signal processor 301 or a plurality of digital signal processor 301, algorithm is cured in the EPROM in the array of digital signal processors, constitutes embedded system, thereby can break away from the PC isolated operation.The multimedia messages of this off line is hidden system and is had advantages such as volume is little, flexible and convenient.The user is the structural parameters of control system and key flexibly also, when needs change parameter and key, only needs the corresponding change of DSP end software macro definitional part is write EPROM again with programmable device again and gets final product.

Fig. 4 is another embodiment of the present invention.In this embodiment, embedded enciphering/deciphering system is made of the array that single field programmable gate array chip 401 or a plurality of field programmable gate array chip 401 combine.

Fig. 5 also is another embodiment of the present invention.In this embodiment, Fu Za programmable logic device array is the embedded enciphering/deciphering system architecture diagram that constitutes by the programmable logic device 501 of the programmable logic device 501 of single complexity or a plurality of complexity.

Fig. 6 to Fig. 9 is the experimental result of method provided by the invention to standard picture encryption and decryption process.

Fig. 6 is the former figure of information; Fig. 7 encrypts the random mask that uses; Fig. 8 is the result after the former figure of information encrypts; Fig. 9 is the former figure of information through correct deciphering.

Various embedded systems in the embodiment of the invention can be embedded in the multiple electronic product goes, as communication, computer, cable TV (CATV set-top box) product, finish secret picture and text, code phone and the various occasion that multimedia messages is had security requirements.

The present invention also is applicable to the application in fields such as video, audio frequency, and promotion prospect is very wide.

Claims (2)

1, a kind of Information hiding method for encryption/decryption based on virtual class holography, this method is by using the electronic installation and the software of parallel hardware and algorithm, the holographic process of simulated optical is characterized in that to comprising the Information hiding enciphering/deciphering of image and voice specific practice is:

Encrypting the encrypting step of holding for image information:

1) based on information plane and random mask are considered as the two-layer of an object, do not introduce under the situation of " reference light " of ordinary meaning, utilize the method for numeral to simulate the record and the reconstruction of the virtual class holography of this two-layer object;

2) computing information plane and random mask branch are clipped to the weighted sum of the discrete fresnel diffraction conversion of virtual class hologram plane, as the record result on the virtual class hologram plane;

3) adopt the method for " spectrum operation " to carry out the digital hologram reconstruction on the plane, Virtual Space, obtain ciphertext.The coding of random mask itself, wavelength X, the discrete fresnel diffraction of random mask is apart from d _m, digital hologram is rebuild distance z, and they all are key parameters of record and process of reconstruction;

Image information after the encryption follows these steps to deciphering after communication line reaches decrypting end:

1) receives correct random mask coded message;

2) utilize corresponding deciphering parameter such as wavelength X, the discrete fresnel diffraction of random mask is apart from d _m, calculate the discrete fresnel diffraction conversion of random mask to virtual class hologram plane, obtain its COMPLEX AMPLITUDE on virtual class hologram plane;

Same reconstruction distance z is carried out the digital hologram reconstruction to the random mask plane when 3) adopting the method for " compose and operate " and utilizing with encryption, and should the distribution value deduct from ciphertext;

4) do the COMPLEX AMPLITUDE that inverse Fourier transform obtains information at the rebuilding plane place of information plane, obtain light intensity by complex amplitude and can recover the prime information image;

Enciphering/deciphering step for voice messaging:

Utilize software that speech data is read in the matrix, utilize array manipulation that its element is rearranged the matrix that makes it to become a N * N again, operate at encryption end and decrypting end enciphering/deciphering step according to above-mentioned image information then.

2, a kind of device of realizing according to the described Information hiding method for encryption/decryption based on virtual class holography of claim 1, it is characterized in that the enciphering/deciphering device comprises the master-slave system that is made of general purpose PC and digital signal processor DSP, or the embedded system of the disengaging PC isolated operation that constitutes by digital signal processor or programmable asic; And device is linked in sequence according to following, the input of device is connected with the output of communication system, the output of device directly is connected with communication line, when original communication system information transmitted is an analog signal, also between the input of enciphering/deciphering device and communication system, add mould/number conversion interface, between the output of enciphering/deciphering device and communication line, add the D/A translation interface.

Images