CN113409339B - Large-view-field hidden extraction method and system for laminated diffraction imaging - Google Patents

Large-view-field hidden extraction method and system for laminated diffraction imaging Download PDF

Info

Publication number
CN113409339B
CN113409339B CN202110719841.8A CN202110719841A CN113409339B CN 113409339 B CN113409339 B CN 113409339B CN 202110719841 A CN202110719841 A CN 202110719841A CN 113409339 B CN113409339 B CN 113409339B
Authority
CN
China
Prior art keywords
image
diffraction pattern
diffraction
visual key
hidden
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.)
Active
Application number
CN202110719841.8A
Other languages
Chinese (zh)
Other versions
CN113409339A (en
Inventor
史祎诗
于涵
杨栋宇
张峻浩
阮天昊
李勇
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.)
University of Chinese Academy of Sciences
Original Assignee
University of Chinese Academy of Sciences
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 University of Chinese Academy of Sciences filed Critical University of Chinese Academy of Sciences
Priority to CN202110719841.8A priority Critical patent/CN113409339B/en
Publication of CN113409339A publication Critical patent/CN113409339A/en
Application granted granted Critical
Publication of CN113409339B publication Critical patent/CN113409339B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
    • G06T7/00—Image analysis
    • G06T7/10—Segmentation; Edge detection
    • G06T7/11—Region-based segmentation
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
    • G06T1/00—General purpose image data processing
    • G06T1/0021—Image watermarking
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
    • G06T7/00—Image analysis
    • G06T7/50—Depth or shape recovery
    • G06T7/55—Depth or shape recovery from multiple images
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
    • G06T9/00—Image coding

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Theoretical Computer Science (AREA)
  • Computer Vision & Pattern Recognition (AREA)
  • Multimedia (AREA)
  • Investigating Or Analysing Materials By Optical Means (AREA)
  • Compression Or Coding Systems Of Tv Signals (AREA)

Abstract

The invention relates to a large-view-field hidden extraction method and system for laminated diffraction imaging. The hiding method comprises the following steps: constructing a reflective laminated imaging system; the reflective stacked imaging system comprises a spatial light modulator and a charge coupled device; encoding the covering image and the original image to generate a plurality of visual key images, and dividing each visual key image into a plurality of divided visual key images; loading a plurality of the segmented visual key images to different pixel positions of the spatial light modulator in sequence according to the acquisition sequence of the laminated imaging image, and acquiring a diffraction pattern corresponding to the segmented visual key images by using the charge-coupled device while loading each segmented visual key image; scrambling the diffraction pattern to generate a scrambled hidden image; and the scrambled hidden image is an image hiding the original image. The invention can realize real-time coding and real-time hiding.

Description

Large-view-field hidden extraction method and system for laminated diffraction imaging
Technical Field
The invention relates to the field of information security, in particular to a large-view-field hidden extraction method and system for laminated diffraction imaging.
Background
Under the development of information explosion, people have higher and higher requirements on safe storage, safe transmission and safe processing of information, so that information safety becomes one of global major problems and is related to various aspects of politics, economy, military, life and the like. The digital information processing is slow in speed and low in efficiency due to the seriousness, and the ever-increasing information security requirements of people cannot be met.
As traditional digital information security research continues to progress, modern optical theory and technology are gradually being incorporated into it. In 1995 researchers first proposed a dual random phase encoded optical image encryption technique based on a 4f imaging system. Compared with other computer electronic means, the optical information encryption technology has the advantages of high parallelism and high processing and transmission speed, and has a rich key space improved by the change of various parameters such as phase, amplitude, wavelength, polarization attitude and the like in an optical system. With optical image encryption technology as a starting end, optical information security technology has been developed rapidly in the last thirty years. In 2007, the american optical society began to embody it in two sub-classification numbers (060.4785, 100.4998) in the optical classification and indexing table (OCIS), which means that optical information security has begun to be a completely independent research area.
In recent years, various encryption methods have been reported in the literature to protect information because the combination of information hiding and optics becomes significant and effective due to the natural physical properties of optical methods, matching and coupling of various parameters, and the design of optical systems. Most of known encryption hiding systems based on optical systems are different, most of them copy or transfer an experimental graph acquired by an experiment, and then perform computer operation to complete related encryption hiding, and cannot synchronize a Charge-coupled Device (CCD), so that real-time encoding and hiding cannot be performed; in addition, the laminated imaging technology needs to obtain a plurality of object pinhole diffraction patterns, which is a very tedious work, but a mechanical movement mode is adopted, so that the real-time performance cannot be realized at all.
Disclosure of Invention
The invention aims to provide a method and a system for extracting large-field hiding of laminated diffraction imaging, which aim to solve the problem of poor real-time performance caused by the fact that real-time hiding cannot be coded in real time.
In order to achieve the purpose, the invention provides the following scheme:
a large field of view hiding method for stacked diffraction imaging comprises the following steps:
constructing a reflective laminated imaging system; the reflective stacked imaging system comprises a spatial light modulator and a charge coupled device;
encoding the covering image and the original image to generate a plurality of visual key images, and dividing each visual key image into a plurality of divided visual key images;
loading a plurality of the segmented visual key images to different pixel positions of the spatial light modulator in sequence according to the acquisition sequence of the laminated imaging image, and acquiring a diffraction pattern corresponding to the segmented visual key images by using the charge-coupled device while loading each segmented visual key image;
scrambling the diffraction pattern to generate a scrambled hidden image; and the scrambled hidden image is an image hiding the original image.
Optionally, the scrambling the diffraction pattern to generate a scrambled hidden image specifically includes:
using formulas
Figure BDA0003136557420000021
Scrambling the diffraction pattern to generate a scrambled hidden image; wherein, T is the hidden image after scrambling;
Figure BDA0003136557420000022
to compress the diffraction spots of the diffraction pattern;
Figure BDA0003136557420000023
arranging the compressed m x n diffraction patterns into a diffraction pattern I with m rows and n columnsm,nThe m-n diffraction patterns are diffraction patterns corresponding to the segmented visual key image, m is the number of rows of pixel points in the diffraction patterns, and n is the number of columns of pixel points in the diffraction patterns; phi (I)m,n) Scrambling process of diffraction pattern of m rows and n columns; alpha is an attenuation factor; h is a host image.
A stacked diffraction imaged large field of view concealment system, comprising: constructing a reflective laminated imaging system; the reflective stacked imaging system comprises a spatial light modulator and a charge coupled device;
the visual key image segmentation module is used for encoding the covering image and the original image to generate a plurality of visual key images and segmenting each visual key image into a plurality of segmented visual key images;
the diffraction pattern determining module is used for sequentially loading a plurality of the segmented visual key images to different pixel positions of the spatial light modulator according to the acquisition sequence of the laminated imaging images, and acquiring diffraction patterns corresponding to the segmented visual key images by using the charge coupled device while loading each segmented visual key image;
the scrambling module is used for scrambling the diffraction pattern to generate a scrambled hidden image; and the scrambled hidden image is an image hiding the original image.
Optionally, the scrambling module specifically includes:
a scrambling unit for using a formula
Figure BDA0003136557420000031
Scrambling the diffraction pattern to generate a scrambled hidden image; wherein, T is the hidden image after scrambling;
Figure BDA0003136557420000032
to compress the diffraction spots of the diffraction pattern;
Figure BDA0003136557420000033
arranging the compressed m x n diffraction patterns into a diffraction pattern I with m rows and n columnsm,nThe m-n diffraction patterns are diffraction patterns corresponding to the segmented visual key image, m is the number of rows of pixel points in the diffraction patterns, and n is the number of columns of pixel points in the diffraction patterns; phi (I)m,n) Scrambling process of diffraction pattern of m rows and n columns; alpha is an attenuation factor; h is a host image.
A large-field-of-view extraction method for laminated diffraction imaging comprises the following steps:
acquiring a scrambled hidden image; the hidden image is an image of a hidden visual key image;
extracting a diffraction pattern of the scrambled hidden image;
reconstructing the diffraction pattern by using an extended stack imaging algorithm to generate a plurality of visual key images;
and carrying out incoherent superposition on the plurality of visual key images to determine an original image.
Optionally, the extracting a diffraction pattern of the scrambled hidden image specifically includes:
using formulas
Figure BDA0003136557420000034
Extracting a diffraction pattern of the scrambled hidden image; wherein, Im,nThe diffraction pattern is a diffraction pattern with m rows and n columns, wherein m is the row number of pixel points in the diffraction pattern, and n is the column number of the pixel points in the diffraction pattern; phi is a-1Is a diffraction pattern Im,nThe sorting process of (1);
Figure BDA0003136557420000035
to reduce the diffraction spots of the diffraction pattern;
Figure BDA0003136557420000036
arranging the compressed m x n diffraction patterns into a diffraction pattern I with m rows and n columnsm,nThe m-n diffraction patterns are diffraction patterns corresponding to the segmented visual key image, m is the number of rows of pixel points in the diffraction patterns, and n is the number of columns of pixel points in the diffraction patterns; t is a hidden image after scrambling; alpha is alpha-1To the negative 1 power of the attenuation factor; h is a host image.
A stacked diffraction imaging large field of view extraction system, comprising:
the hidden image acquisition module is used for acquiring the scrambled hidden image; the scrambled hidden image is an image of a hidden visual key image;
the diffraction pattern extraction module is used for extracting the diffraction pattern of the scrambled hidden image;
the visual key image generation module is used for reconstructing the diffraction pattern by using an extended laminated imaging algorithm to generate a plurality of visual key images;
and the original image determining module is used for carrying out incoherent superposition on the plurality of visual key images to determine an original image.
Optionally, the diffraction pattern extraction module specifically includes:
a diffraction pattern extraction unit for using the formula
Figure BDA0003136557420000041
Extracting a diffraction pattern of the scrambled hidden image; wherein, Im,nThe diffraction pattern is a diffraction pattern with m rows and n columns, wherein m is the row number of pixel points in the diffraction pattern, and n is the column number of the pixel points in the diffraction pattern; phi is a-1Is a diffraction pattern Im,nThe sorting process of (1);
Figure BDA0003136557420000042
to reduce the diffraction spots of the diffraction pattern;
Figure BDA0003136557420000043
arranging the compressed m x n diffraction patterns into a diffraction pattern I with m rows and n columnsm,nThe m-n diffraction patterns are diffraction patterns corresponding to the segmented visual key image, m is the number of rows of pixel points in the diffraction patterns, and n is the number of columns of pixel points in the diffraction patterns; t is a hidden image after scrambling; alpha is alpha-1To the negative 1 power of the attenuation factor; h is a host image.
A large-field-of-view hidden extraction method for laminated diffraction imaging comprises the following steps: constructing a reflective laminated imaging system; the reflective stacked imaging system comprises a spatial light modulator and a charge coupled device;
encoding the covering image and the original image to generate a plurality of visual key images, and dividing each visual key image into a plurality of divided visual key images;
loading a plurality of the segmented visual key images to different pixel positions of the spatial light modulator in sequence according to the acquisition sequence of the laminated imaging image, and acquiring a diffraction pattern corresponding to the segmented visual key images by using the charge-coupled device while loading each segmented visual key image;
scrambling the diffraction pattern to generate a scrambled hidden image; the scrambled hidden image is an image hiding the original image;
extracting a diffraction pattern of the scrambled hidden image;
reconstructing the diffraction pattern by using an extended stack imaging algorithm to generate a plurality of visual key images;
and carrying out incoherent superposition on the plurality of visual key images to determine an original image.
A stacked diffraction imaged large field of view hidden extraction system, comprising: constructing a reflective laminated imaging system; the reflective stacked imaging system comprises a spatial light modulator and a charge coupled device;
the visual key image segmentation module is used for encoding the covered image and the original image to generate a plurality of visual key images and segmenting each visual key image into a plurality of segmented visual key images;
the diffraction pattern determining module is used for sequentially loading a plurality of the segmented visual key images to different pixel positions of the spatial light modulator according to the acquisition sequence of the laminated imaging image, and acquiring diffraction patterns corresponding to the segmented visual key images by using the charge coupled device while loading each segmented visual key image;
the scrambling module is used for scrambling the diffraction pattern to generate a scrambled hidden image; the scrambled hidden image is an image hiding the original image;
a diffraction pattern extraction module for extracting the diffraction pattern of the scrambled hidden image;
the visual key image generation module is used for reconstructing the diffraction pattern by using an extended laminated imaging algorithm to generate a plurality of visual key images;
and the original image determining module is used for carrying out incoherent superposition on the plurality of visual key images to determine an original image.
According to the specific embodiment provided by the invention, the invention discloses the following technical effects: the invention provides a large-view-field hidden extraction method and system for laminated diffraction imaging, wherein a reflective laminated imaging system is built, a spatial light modulator and a charge coupled device are connected together, a plurality of segmented visual key images are sequentially loaded to different pixel positions of the spatial light modulator, and the charge coupled device is used for collecting diffraction patterns corresponding to the segmented visual key images while loading each segmented visual key image, so that synchronous working of the spatial light modulator and the charge coupled device is realized, and real-time encoding and real-time hiding are realized; meanwhile, the whole process of the invention does not need mechanical movement, and the original image can be coded and hidden only by using a computer, thereby realizing the real-time performance of coding and hiding.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.
FIG. 1 is a flow chart of a method for extracting large field of view hiding in laminated diffraction imaging according to the present invention;
FIG. 2 is an optical diagram of a reflective stacked imaging system;
FIG. 3 is a graph of results of an information hiding experiment;
fig. 4 is a schematic diagram of a visual key image recovered at different wavelengths.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The invention aims to provide a method and a system for extracting large-view-field hiding of laminated diffraction imaging, which can realize real-time coding and real-time hiding.
In order to make the aforementioned objects, features and advantages of the present invention more comprehensible, the present invention is described in detail with reference to the accompanying drawings and the detailed description thereof.
A large field of view hiding method for stacked diffraction imaging comprises the following steps: constructing a reflective laminated imaging system; the reflective stacked imaging system comprises a spatial light modulator and a charge coupled device; encoding the covering image and the original image to generate a plurality of visual key images, and dividing each visual key image into a plurality of divided visual key images; loading a plurality of the segmented visual key images to different pixel positions of the spatial light modulator in sequence according to the acquisition sequence of the laminated imaging image, and acquiring a diffraction pattern corresponding to the segmented visual key images by using the charge-coupled device while loading each segmented visual key image; scrambling the diffraction pattern to generate a scrambled hidden image; and the scrambled hidden image is an image hiding the original image.
The scrambling the diffraction pattern to generate a scrambled hidden image specifically includes: using formulas
Figure BDA0003136557420000061
Scrambling the diffraction pattern to generate a scrambled hidden image; wherein, T is the hidden image after scrambling;
Figure BDA0003136557420000062
to compress the diffraction spots of the diffraction pattern;
Figure BDA0003136557420000063
to compress m x nDiffraction diagram I with m rows and n columnsm,nThe m-n diffraction patterns are diffraction patterns corresponding to the segmented visual key image, m is the number of rows of pixel points in the diffraction patterns, and n is the number of columns of pixel points in the diffraction patterns; phi (I)m,n) Scrambling process of diffraction pattern of m rows and n columns; alpha is an attenuation factor; h is a host image.
A large-field-of-view extraction method for laminated diffraction imaging comprises the following steps: acquiring a scrambled hidden image; the hidden image is an image of a hidden visual key image; extracting a diffraction pattern of the scrambled hidden image; reconstructing the diffraction pattern by using an extended stack imaging algorithm to generate a plurality of visual key images; and carrying out incoherent superposition on the plurality of visual key images to determine an original image.
The extracting the diffraction pattern of the scrambled hidden image specifically includes: using formulas
Figure BDA0003136557420000071
Extracting a diffraction pattern of the scrambled hidden image; wherein, Im,nThe diffraction pattern is a diffraction pattern with m rows and n columns, wherein m is the row number of pixel points in the diffraction pattern, and n is the column number of the pixel points in the diffraction pattern;φ -1is a diffraction pattern Im,nThe sorting process of (1);
Figure BDA0003136557420000072
to reduce the diffraction spots of the diffraction pattern;
Figure BDA0003136557420000073
arranging the compressed m x n diffraction patterns into a diffraction pattern I with m rows and n columnsm,nThe m-n diffraction patterns are diffraction patterns corresponding to the segmented visual key image, m is the number of rows of pixel points in the diffraction patterns, and n is the number of columns of pixel points in the diffraction patterns; t is a hidden image after scrambling; alpha is alpha-1To the negative 1 power of the attenuation factor; h is a host image. In the practical application of the method, the material is,
Figure BDA0003136557420000074
to obtain the diffraction pattern Im,nAnd splitting the image into m x n diffraction patterns, wherein the m x n diffraction patterns are diffraction patterns corresponding to the split visual key image.
Fig. 1 is a flowchart of a method for extracting a large field of view hiding in stacked diffraction imaging provided by the present invention, and as shown in fig. 1, the method for extracting a large field of view hiding in stacked diffraction imaging includes:
step 101: constructing a reflective laminated imaging system; the reflective stacked imaging system includes a spatial light modulator and a charge coupled device.
Step 102: and coding the covering image and the original image to generate a plurality of visual key images, and dividing each visual key image into a plurality of divided visual key images.
Step 103: and sequentially loading a plurality of the segmented visual key images to different pixel positions of the spatial light modulator according to the acquisition sequence of the laminated imaging image, and acquiring a diffraction pattern corresponding to the segmented visual key images by using the charge coupled device while loading each segmented visual key image.
Step 104: scrambling the diffraction pattern to generate a scrambled hidden image; and the scrambled hidden image is an image hiding the original image.
Step 105: and extracting a diffraction pattern of the scrambled hidden image.
Step 106: and reconstructing the diffraction pattern by using an extended stack imaging algorithm to generate a plurality of visual key images.
Step 107: and carrying out incoherent superposition on the plurality of visual key images to determine an original image.
In practical application, the invention is divided into two parts:
step 1: constructing a reflective stacked imaging system, which comprises a Spatial Light Modulator (SLM) for loading information and a Charge-coupled Device (CCD) for collecting data;
step 2: cutting 2 visual keys into 72 small pictures of the visual keys at a computer end;
and step 3: sequentially loading 72 visual keys to different pixel positions of a liquid crystal display of the SLM according to the sequence of laminated imaging image acquisition, and acquiring corresponding diffraction patterns I on the CCD when each image is loaded1,1，I1,2…Im,n-1，Im,nWhere m and n represent the number of rows and columns, respectively.
The diffraction pattern containing the information is hidden by a reflective stack imaging method.
The hiding process of the information is as follows:
and 4, step 4: scrambling the diffraction patterns in sequence to obtain an image to be transmitted;
Figure BDA0003136557420000081
the information extraction and reconstruction process comprises the following steps:
and 5: extracting a diffraction pattern:
Figure BDA0003136557420000082
wherein phi-1Showing the sequence of the diffraction patterns (the sequence of CCD acquisitions in the mounting step 3 is numbered 1,2, … m n in order); the symbol phi represents the scrambling process of the diffraction pattern (the number of the diffraction pattern acquired by the CCD in the mounting step 3 is scrambled); phi is a-1Showing the sequence of the diffraction patterns (the sequence of CCD acquisitions in the mounting step 3 is numbered 1,2, … m n in order);
Figure BDA0003136557420000083
and
Figure BDA0003136557420000084
representing the compression and recovery of the diffraction spot;
Figure BDA0003136557420000085
representing a large image I with m x n compressed diffraction patterns arranged in m rows and n columnsm,n；
Figure BDA0003136557420000086
Represents thatm,nSplitting into m x n individual diffractograms; alpha is an attenuation factor; alpha is alpha-1To the negative 1 power of the attenuation factor; h is a host image; t is a hidden image after scrambling; namely: and sequentially scrambling, compressing, combining and hiding the diffraction pattern in the host image to obtain the image to be transmitted.
Step 6: after the diffraction pattern is obtained, it is reconstructed by recovery. The diffraction pattern I obtained here is the extended Ptycholographic Iterative Engine (ePIE) pair in the Ptycholographic imagingm,nCarrying out reconstruction;
and 7: and after the reconstruction is recovered, a visual key hidden by the laminated imaging system can be obtained, and the two visual keys are subjected to incoherent superposition to obtain secret information.
The technical solution of the present invention is described below in terms of a specific experimental procedure.
Fig. 2 is an optical path diagram of a reflective stacked imaging system, in fig. 2, Laser is a Laser, CVF is an attenuator, Mirror is a reflector, AT is a polarizer, Filter is a beam expander, PBS is a polarization splitting prism, Lens is a Lens, Pinhole1 is a diaphragm, BS is a splitting prism, CCD is a charge coupled device, SLM is a spatial light modulator, and PC is a calculator. The specific experimental parameters were as follows: laser, gas Laser wavelength 632.8nm, red, Mirror, AT: polarizing plate, fitter: spatial filter, Lens: collimating lens, Pinhole 1: small-pore probe, BS: beam splitter prism, PBS: polarization splitting prism, SLM: reflective spatial light modulator, Holoeye reflective pure phase spatial light modulator (PLUTO-VIS-016-SLM), CCD: the CCD (model IGV-B4020M-KF000) pixel size of IMPERX is 9um, and the actual usage wavefront size is 1024X1024 pix. With the scanning mode of 6X6, the fault tolerance of the visual password is about 7% at the lowest. Diffraction distance Z182 mm, PC: and a computer connected with the CCD and the SLM.
The laser beam is adjusted into a parallel beam through the reflector, the single light spot is small, the parallel beam is shaped into a plane wave after passing through the spatial filter and the collimating lens, the beam is large, the attenuator is used for adjusting the laser intensity to meet the requirement of subsequent experiments, the PBS is used for meeting the pure phase modulation requirement of the SLM, the laser beam passes through the probe small hole through the polarizer, the irradiated reflective spatial light modulator enters the CCD through the BS reflection, and finally the CCD receives a diffraction pattern and transmits the diffraction pattern to the PC computer.
Description of the experimental operation procedure of the optical path:
(1) no mechanical movement exists in the light path, no matter a moving object or a moving small-hole probe is selected, in the experiment, the invention does not need to move any instrument, and the relative displacement can be obtained by using a computer.
(2) Reflective spatial light modulators are used because the diffraction patterns collected in experiments in particular real life are almost reflective, at least transmissive, as the human eye is reflective imaging.
(3) The invention realizes the synchronous work of the CCD and the SLM after connecting the CCD and the SLM together, which realizes the real-time property provided by the invention, certainly not only is limited to a visual key, but also can carry out real-time coding and then hiding no matter what image information needs to be hidden is replaced, which is different from most known encryption and hiding systems, most of the encryption and hiding systems copy or transfer experimental graphs acquired by experiments, then carry out the operation of a computer to complete the related encryption and hiding, and cannot synchronize the CCD.
(4) The laminated imaging technology needs to obtain a plurality of object pinhole diffraction patterns, which is a very tedious work, however, the real-time performance cannot be realized at all by adopting a mechanical movement mode, so that the system has no mechanical movement and has the advantage of real-time performance.
Fig. 3 is a diagram showing the result of an information hiding experiment, and as shown in fig. 3, a masking image and secret information (original image) are first selected, and then an Enhanced Visual Cryptography (EVC) is used to obtain two pieces of shared information (visual key image). Respectively cutting the two visual keys into 6 × 6 small graphs, loading 72 small graphs of the visual keys to an area array area on the SLM, collecting 72 diffraction graphs in total, respectively arranging the diffraction graphs of the two visual keys in sequence, recovering the two visual keys by using an ePIE algorithm, and finally performing incoherent superposition on the recovered two visual keys to obtain secret information.
Fig. 4 is a schematic diagram of the visual key image recovered by different wavelengths, and it is apparent from fig. 4 that the best recovery is achieved when the wavelength lambda is 632.8nm, and the best effect can be decoded when the data is consistent with that used in the experiment. The invention can provide the support that the shape, the size, the sequence, the position, the wavelength, the diffraction distance and the like of the probe can provide safety for the system. In practical application, the specific content of the visual key cannot be seen by randomly changing the sequence of 6 diffraction patterns, so that the enhanced visual password and the large-field-of-view hiding method of the laminated diffraction imaging can be seen, and the method has feasibility and high safety.
In addition, the invention also discloses a large-view-field hiding system for laminated diffraction imaging, which comprises: constructing a reflective laminated imaging system; the reflective stacked imaging system comprises a spatial light modulator and a charge coupled device; the visual key image segmentation module is used for encoding the covering image and the original image to generate a plurality of visual key images and segmenting each visual key image into a plurality of segmented visual key images; the diffraction pattern determining module is used for sequentially loading a plurality of the segmented visual key images to different pixel positions of the spatial light modulator according to the acquisition sequence of the laminated imaging images, and acquiring diffraction patterns corresponding to the segmented visual key images by using the charge coupled device while loading each segmented visual key image; the scrambling module is used for scrambling the diffraction pattern to generate a scrambled hidden image; and the scrambled hidden image is an image hiding the original image.
The scrambling module specifically comprises: a scrambling unit for using the formula
Figure BDA0003136557420000111
Scrambling the diffraction pattern to generate a scrambled hidden image; wherein T is the hidden image after scrambling；
Figure BDA0003136557420000112
To compress the diffraction spots of the diffraction pattern;
Figure BDA0003136557420000113
arranging the compressed m x n diffraction patterns into a diffraction pattern I with m rows and n columnsm,nThe m-n diffraction patterns are diffraction patterns corresponding to the segmented visual key image, m is the number of rows of pixel points in the diffraction patterns, and n is the number of columns of pixel points in the diffraction patterns; phi (I)m,n) Scrambling process of diffraction pattern of m rows and n columns; alpha is an attenuation factor; h is a host image.
A stacked diffraction imaging large field of view extraction system, comprising: the hidden image acquisition module is used for acquiring the scrambled hidden image; the scrambled hidden image is an image of a hidden visual key image; the diffraction pattern extraction module is used for extracting the diffraction pattern of the scrambled hidden image; the visual key image generation module is used for reconstructing the diffraction pattern by using an extended stack imaging algorithm to generate a plurality of visual key images; and the original image determining module is used for carrying out incoherent superposition on the plurality of visual key images to determine an original image.
The diffraction pattern extraction module specifically comprises: a diffraction pattern extraction unit for using the formula
Figure BDA0003136557420000114
Extracting a diffraction pattern of the scrambled hidden image; wherein, Im,nThe diffraction pattern is a diffraction pattern with m rows and n columns, wherein m is the row number of pixel points in the diffraction pattern, and n is the column number of the pixel points in the diffraction pattern; phi is a-1Is a diffraction pattern Im,nThe sorting process of (2);
Figure BDA0003136557420000115
to reduce the diffraction spots of the diffraction pattern;
Figure BDA0003136557420000116
for arranging compressed m x n diffraction patternsDiffraction pattern I with m rows and n columnsm,nThe m-n diffraction patterns are diffraction patterns corresponding to the segmented visual secret key image, m is the number of rows of pixel points in the diffraction patterns, and n is the number of columns of pixel points in the diffraction patterns; t is a hidden image after scrambling; alpha (alpha) ("alpha")-1To the negative 1 power of the attenuation factor; h is a host image.
A stacked diffraction imaged large field of view hidden extraction system, comprising: constructing a reflective laminated imaging system; the reflective stacked imaging system comprises a spatial light modulator and a charge coupled device; the visual key image segmentation module is used for encoding the covering image and the original image to generate a plurality of visual key images and segmenting each visual key image into a plurality of segmented visual key images; the diffraction pattern determining module is used for sequentially loading a plurality of the segmented visual key images to different pixel positions of the spatial light modulator according to the acquisition sequence of the laminated imaging images, and acquiring diffraction patterns corresponding to the segmented visual key images by using the charge coupled device while loading each segmented visual key image; the scrambling module is used for scrambling the diffraction pattern to generate a scrambled hidden image; the scrambled hidden image is an image hiding the original image; the diffraction pattern extraction module is used for extracting the diffraction pattern of the scrambled hidden image; the visual key image generation module is used for reconstructing the diffraction pattern by using an extended laminated imaging algorithm to generate a plurality of visual key images; and the original image determining module is used for carrying out incoherent superposition on the plurality of visual key images to determine an original image.
The invention provides a method for extracting information by applying non-mechanical mobile overlay (NPE) imaging after a masked image and a secret image are subjected to an Enhanced Visual Cryptography (EVC) scheme. Because the laminated diffraction imaging technology has the advantages of large field of view, good imaging quality and the like. Therefore, the enhanced visual password is combined with non-mechanical movable type laminated optical image hiding, the problem that large visual field information is difficult to coherently superpose can be solved, and the security is high.
In the invention, the implementation process is as follows: 1) first, a mask image and secret information are selected, and two shared images VK1 and VK2 are obtained by using enhanced visual cryptography.
2) Two share images VK1 and VK2 were cut into 6X6 pictures, respectively, for a total of 72.
3) And loading 72 pieces of information to a spatial light modulator through a non-mechanical laminated imaging light path by using a reflective coherent diffraction imaging system, acquiring corresponding diffraction images on a charge coupled device while loading 72 pieces of information until all diffraction patterns corresponding to the 72 pieces of information are acquired, and storing the diffraction patterns in a diffraction database after the optical system is encoded.
4) The diffraction patterns in the diffraction database are ranked in order.
5) When information is extracted, the epie algorithm is used for recovering the ordered diffraction patterns, and meanwhile, parameters such as diffraction distance, moving distance and the like are required to be known, so that secret information can be accurately and completely extracted.
6) The safety of the scheme is tested, namely scrambling codes and aspects of wavelength, pixel size, diffraction distance and the like.
Therefore, the invention can achieve the following effects:
1) safety: the laminated diffraction imaging technology needs matching and coupling of various parameters, such as scrambling codes, wavelengths, pixel sizes, diffraction distances and other parameters, and ensures the safety of the system.
2) Large capacity: the combination of enhanced visual cryptography and stacked diffraction imaging solves the problem of incoherent superposition of large-field pictures.
3) And (3) timeliness: and simultaneously controlling the CCD and the SLM by using a computer (PC), wherein the frame rates of the CCD and the SLM are 1/60(s), namely, 60 visual keys can be adopted as corresponding diffraction patterns at most every second, and certain timeliness is achieved.
4) Stability: once the optical system is completely built, other changes are not needed, and information hiding and extraction can be quickly finished on a PC.
The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. For the system disclosed by the embodiment, the description is relatively simple because the system corresponds to the method disclosed by the embodiment, and the relevant points can be referred to the method part for description.
The principles and embodiments of the present invention have been described herein using specific examples, which are provided only to help understand the method and the core concept of the present invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, the specific embodiments and the application range may be changed. In view of the above, the present disclosure should not be construed as limiting the invention.

Claims (6)

1. A method for hiding a large field of view of laminated diffraction imaging is characterized by comprising the following steps:
constructing a reflective laminated imaging system; the reflective stacked imaging system comprises a spatial light modulator and a charge coupled device;
encoding the covering image and the original image to generate a plurality of visual key images, and dividing each visual key image into a plurality of divided visual key images;
loading a plurality of the segmented visual key images to different pixel positions of the spatial light modulator in sequence according to the acquisition sequence of the laminated imaging image, and acquiring a diffraction pattern corresponding to the segmented visual key images by using the charge-coupled device while loading each segmented visual key image;
scrambling the diffraction pattern to generate a scrambled hidden image; the scrambled hidden image is an image hiding the original image;
the scrambling the diffraction pattern to generate a scrambled hidden image specifically includes:
using formulas
Figure FDA0003642707790000011
Scrambling said diffraction pattern to generateForming a scrambled hidden image; wherein, T is the hidden image after scrambling;
Figure FDA0003642707790000012
to compress the diffraction spots of the diffraction pattern;
Figure FDA0003642707790000013
arranging the compressed m x n diffraction patterns into a diffraction pattern I with m rows and n columnsm,nThe m-n diffraction patterns are diffraction patterns corresponding to the segmented visual key image, m is the number of rows of pixel points in the diffraction patterns, and n is the number of columns of pixel points in the diffraction patterns; phi (I)m,n) Scrambling process of diffraction pattern of m rows and n columns; alpha is an attenuation factor; h is a host image.
2. A stacked diffraction imaging large field of view concealment system, comprising: constructing a reflective laminated imaging system; the reflective stacked imaging system comprises a spatial light modulator and a charge coupled device;
the visual key image segmentation module is used for encoding the covering image and the original image to generate a plurality of visual key images and segmenting each visual key image into a plurality of segmented visual key images;
the diffraction pattern determining module is used for sequentially loading a plurality of the segmented visual key images to different pixel positions of the spatial light modulator according to the acquisition sequence of the laminated imaging images, and acquiring diffraction patterns corresponding to the segmented visual key images by using the charge coupled device while loading each segmented visual key image;
the scrambling module is used for scrambling the diffraction pattern to generate a scrambled hidden image; the scrambled hidden image is an image hiding the original image;
the scrambling module specifically comprises:
a scrambling unit for using a formula
Figure FDA0003642707790000021
Scrambling the diffraction pattern to generate a scrambled hidden image; wherein, T is the hidden image after scrambling;
Figure FDA0003642707790000022
to compress the diffraction spots of the diffraction pattern;
Figure FDA0003642707790000023
arranging the compressed m x n diffraction patterns into a diffraction pattern I with m rows and n columnsm,nThe m-n diffraction patterns are diffraction patterns corresponding to the segmented visual secret key image, m is the number of rows of pixel points in the diffraction patterns, and n is the number of columns of pixel points in the diffraction patterns; phi (I)m,n) Scrambling process of diffraction pattern of m rows and n columns; alpha is an attenuation factor; h is a host image.
3. A large field of view extraction method for laminated diffraction imaging is characterized by comprising the following steps:
acquiring a scrambled hidden image; the hidden image is an image of a hidden visual key image;
extracting a diffraction pattern of the scrambled hidden image;
the extracting the diffraction pattern of the scrambled hidden image specifically includes:
using formulas
Figure FDA0003642707790000024
Extracting a diffraction pattern of the scrambled hidden image; wherein, Im,nThe diffraction pattern is a diffraction pattern with m rows and n columns, wherein m is the row number of pixel points in the diffraction pattern, and n is the column number of the pixel points in the diffraction pattern; phi is a-1Diffraction Pattern Im,nThe sorting process of (1);
Figure FDA0003642707790000025
to reduce the diffraction spots of the diffraction pattern;
Figure FDA0003642707790000026
arranging the compressed m x n diffraction patterns into a diffraction pattern I with m rows and n columnsm,nThe m-n diffraction patterns are diffraction patterns corresponding to the segmented visual key image, m is the number of rows of pixel points in the diffraction patterns, and n is the number of columns of pixel points in the diffraction patterns; t is a hidden image after scrambling; alpha is alpha-1To the negative 1 power of the attenuation factor; h is a host image;
reconstructing the diffraction pattern by using an extended stack imaging algorithm to generate a plurality of visual key images;
and carrying out incoherent superposition on the plurality of visual key images to determine an original image.
4. A stacked diffraction imaging large field of view extraction system, comprising:
the hidden image acquisition module is used for acquiring the scrambled hidden image; the scrambled hidden image is an image of a hidden visual key image;
the diffraction pattern extraction module is used for extracting the diffraction pattern of the scrambled hidden image;
the diffraction pattern extraction module specifically comprises:
a diffraction pattern extraction unit for using the formula
Figure FDA0003642707790000031
Figure FDA0003642707790000032
Extracting a diffraction pattern of the scrambled hidden image; wherein, Im,nThe diffraction pattern is a diffraction pattern with m rows and n columns, wherein m is the row number of pixel points in the diffraction pattern, and n is the column number of the pixel points in the diffraction pattern; phi is a-1Is a diffraction pattern Im,nThe sorting process of (1);
Figure FDA0003642707790000033
to reduce the diffraction spots of the diffraction pattern;
Figure FDA0003642707790000034
arranging the compressed m x n diffraction patterns into a diffraction pattern I with m rows and n columnsm,nThe m-n diffraction patterns are diffraction patterns corresponding to the segmented visual key image, m is the number of rows of pixel points in the diffraction patterns, and n is the number of columns of pixel points in the diffraction patterns; t is a hidden image after scrambling; alpha is alpha-1To the negative 1 power of the attenuation factor; h is a host image;
the visual key image generation module is used for reconstructing the diffraction pattern by using an extended laminated imaging algorithm to generate a plurality of visual key images;
and the original image determining module is used for carrying out incoherent superposition on the plurality of visual key images to determine an original image.
5. A large-field-of-view hidden extraction method for laminated diffraction imaging is characterized by comprising the following steps: constructing a reflective laminated imaging system; the reflective stacked imaging system comprises a spatial light modulator and a charge coupled device;
encoding the covering image and the original image to generate a plurality of visual key images, and dividing each visual key image into a plurality of divided visual key images;
loading a plurality of the segmented visual key images to different pixel positions of the spatial light modulator in sequence according to the acquisition sequence of the laminated imaging image, and acquiring a diffraction pattern corresponding to the segmented visual key images by using the charge-coupled device while loading each segmented visual key image;
scrambling the diffraction pattern to generate a scrambled hidden image; the scrambled hidden image is an image hiding the original image;
the scrambling the diffraction pattern to generate a scrambled hidden image specifically includes:
using formulas
Figure FDA0003642707790000041
Scrambling the diffraction pattern to generate a scrambled patternHiding the image; wherein, T is the hidden image after scrambling;
Figure FDA0003642707790000042
to compress the diffraction spots of the diffraction pattern;
Figure FDA0003642707790000043
arranging the compressed m x n diffraction patterns into a diffraction pattern I with m rows and n columnsm,nThe m-n diffraction patterns are diffraction patterns corresponding to the segmented visual key image, m is the number of rows of pixel points in the diffraction patterns, and n is the number of columns of pixel points in the diffraction patterns; phi (I)m,n) Scrambling process of diffraction pattern of m rows and n columns; alpha is an attenuation factor; h is a host image;
extracting a diffraction pattern of the scrambled hidden image;
the extracting the diffraction pattern of the scrambled hidden image specifically includes:
using formulas
Figure FDA0003642707790000044
Extracting a diffraction pattern of the scrambled hidden image; wherein, Im,nThe diffraction pattern is a diffraction pattern with m rows and n columns, wherein m is the row number of pixel points in the diffraction pattern, and n is the column number of the pixel points in the diffraction pattern; phi is a-1Diffraction Pattern Im,nThe sorting process of (1);
Figure FDA0003642707790000045
to reduce the diffraction spots of the diffraction pattern;
Figure FDA0003642707790000046
arranging the compressed m x n diffraction patterns into a diffraction pattern I with m rows and n columnsm,nThe m-n diffraction patterns are diffraction patterns corresponding to the segmented visual key image, m is the number of rows of pixel points in the diffraction patterns, and n is the number of columns of pixel points in the diffraction patterns; t is a hidden image after scrambling; alpha is alpha-1To the negative 1 power of the attenuation factor; h is a host image;
reconstructing the diffraction pattern by using an extended stack imaging algorithm to generate a plurality of visual key images;
and carrying out incoherent superposition on the plurality of visual key images to determine an original image.
6. A stacked diffraction imaging large field of view hidden extraction system, comprising: constructing a reflective laminated imaging system; the reflective stacked imaging system comprises a spatial light modulator and a charge coupled device;
the visual key image segmentation module is used for encoding the covering image and the original image to generate a plurality of visual key images and segmenting each visual key image into a plurality of segmented visual key images;
the diffraction pattern determining module is used for sequentially loading a plurality of the segmented visual key images to different pixel positions of the spatial light modulator according to the acquisition sequence of the laminated imaging images, and acquiring diffraction patterns corresponding to the segmented visual key images by using the charge coupled device while loading each segmented visual key image;
the scrambling module is used for scrambling the diffraction pattern to generate a scrambled hidden image; the scrambled hidden image is an image hiding the original image;
the scrambling module specifically comprises:
a scrambling unit for using the formula
Figure FDA0003642707790000051
Scrambling the diffraction pattern to generate a scrambled hidden image; wherein, T is the hidden image after scrambling;
Figure FDA0003642707790000052
to compress the diffraction spots of the diffraction pattern;
Figure FDA0003642707790000053
to m after compressionn diffraction patterns arranged as a diffraction pattern I with m rows and n columnsm,nThe m-n diffraction patterns are diffraction patterns corresponding to the segmented visual key image, m is the number of rows of pixel points in the diffraction patterns, and n is the number of columns of pixel points in the diffraction patterns; phi (I)m,n) Scrambling process of diffraction pattern of m rows and n columns; alpha is an attenuation factor; h is a host image;
the diffraction pattern extraction module is used for extracting the diffraction pattern of the scrambled hidden image;
the diffraction pattern extraction module specifically comprises:
a diffraction pattern extraction unit for using the formula
Figure FDA0003642707790000061
Figure FDA0003642707790000062
Extracting a diffraction pattern of the scrambled hidden image; wherein, Im,nThe diffraction pattern is a diffraction pattern with m rows and n columns, wherein m is the row number of pixel points in the diffraction pattern, and n is the column number of the pixel points in the diffraction pattern; phi is a-1Is a diffraction pattern Im,nThe sorting process of (1);
Figure FDA0003642707790000063
to reduce the diffraction spots of the diffraction pattern;
Figure FDA0003642707790000064
arranging the compressed m x n diffraction patterns into a diffraction pattern I with m rows and n columnsm,nThe m-n diffraction patterns are diffraction patterns corresponding to the segmented visual key image, m is the number of rows of pixel points in the diffraction patterns, and n is the number of columns of pixel points in the diffraction patterns; t is a hidden image after scrambling; alpha is alpha-1To the negative 1 power of the attenuation factor; h is a host image;
the visual key image generation module is used for reconstructing the diffraction pattern by using an extended laminated imaging algorithm to generate a plurality of visual key images;
and the original image determining module is used for carrying out incoherent superposition on the plurality of visual key images to determine an original image.
CN202110719841.8A 2021-06-28 2021-06-28 Large-view-field hidden extraction method and system for laminated diffraction imaging Active CN113409339B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202110719841.8A CN113409339B (en) 2021-06-28 2021-06-28 Large-view-field hidden extraction method and system for laminated diffraction imaging

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202110719841.8A CN113409339B (en) 2021-06-28 2021-06-28 Large-view-field hidden extraction method and system for laminated diffraction imaging

Publications (2)

Publication Number Publication Date
CN113409339A CN113409339A (en) 2021-09-17
CN113409339B true CN113409339B (en) 2022-07-08

Family

ID=77679781

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202110719841.8A Active CN113409339B (en) 2021-06-28 2021-06-28 Large-view-field hidden extraction method and system for laminated diffraction imaging

Country Status (1)

Country Link
CN (1) CN113409339B (en)

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110728164A (en) * 2019-10-22 2020-01-24 中国科学院大学 Real-time information hiding system and method based on two-dimensional code and reflective stacked imaging
US10768339B1 (en) * 2017-07-25 2020-09-08 Southern Methodist University Imaging hidden objects
CN111861850A (en) * 2020-07-21 2020-10-30 中国科学院大学 Information hiding method and system for laminated imaging

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10768339B1 (en) * 2017-07-25 2020-09-08 Southern Methodist University Imaging hidden objects
CN110728164A (en) * 2019-10-22 2020-01-24 中国科学院大学 Real-time information hiding system and method based on two-dimensional code and reflective stacked imaging
CN111861850A (en) * 2020-07-21 2020-10-30 中国科学院大学 Information hiding method and system for laminated imaging

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
《Multiple-Image Hiding by Using Single-Shot Ptychography in Transform Domain》;Wenhui Xu et al.;《IEEE Photonics Journal》;20170424;第09卷(第03期);全文 *
《基于增强型视觉密码的光学信息隐藏系统》;于韬 等;《物理学报》;20200723;第69卷(第14期);全文 *

Also Published As

Publication number Publication date
CN113409339A (en) 2021-09-17

Similar Documents

Publication Publication Date Title
CN110728164B (en) Real-time information hiding system and method based on two-dimensional code and reflective stacked imaging
CN109407199B (en) Construction method and encryption and decryption method of holographic element, holographic element and device
CN110942413B (en) Method and system for hiding and extracting large-capacity optical information
CN104159094A (en) Method for improving optical scanning holographic tomography effect
CN108089425B (en) A method of the elimination optical scanner holography defocus noise based on deep learning
JP7122153B2 (en) Hologram recording device and image reproducing device
CN106707680B (en) A kind of holographic projection methods based on light field
CN103763543B (en) The acquisition method of resultant hologram
CN111861850B (en) Information hiding method and system for laminated imaging
Velez et al. Optical field data compression by opto-digital means
CN113409339B (en) Large-view-field hidden extraction method and system for laminated diffraction imaging
CN104182996A (en) Compression storage and quick recovery method of digital element hologram
Zhuang et al. Deep-learning-based ciphertext-only attack on optical scanning cryptosystem
CN113438382B (en) Lossless information hiding and extracting method and system for visual password
Jaramillo-Osorio et al. Experimental Fresnel and Fourier digital holography using a digital micro-mirror device
Trejos et al. Experimental opto-digital processing of multiple data via modulation, packaging and encryption
CN111897196B (en) Method and system for hiding and extracting digital holographic information
Wang et al. Image feature extraction with the optical Haar wavelet transform
CN113658330B (en) Holographic encoding method based on neural network
Qin et al. Optical compressive encryption via deep learning
Gilles et al. Open access dataset of holographic videos for codec analysis and machine learning applications
Barrera et al. Experimental protocol for packaging and encrypting multiple data
CN112099329B (en) Multi-three-dimensional object encryption and decryption method based on cascade decryption phase template and binary encryption phase template
Dou et al. Coded aperture temporal compressive digital holographic microscopy
Vargas et al. Digital image compression for a 2f multiplexing optical setup

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant