AU2020104195A4 - A method for data security using virtual key replacement in image steganography - Google Patents

Abstract

A METHOD FOR DATA SECURITY USING VIRTUAL KEY REPLACEMENT IN IMAGE STEGANOGRAPHY The present invention relates to a method for data security using virtual key replacement method in image steganography.The object of the proposed invention is toprovide a virtual key replacement method which consolidates the advantages of LSB &compression techniques to serve improved safeguard to the picture regarding data embedding capacity. Present invention chose pixel to hide the knowledge interested in the cover portrait. Most of strategy effectively distinguishes the information behind the picture. Because of this dread, proposed technique utilizes red, green and blue segment to conceal the information. By utilizing this approach it is extremely hard to recognize the information behind the picture. Each pixel in a picture comprises of red, green and blue components. The proposed instruments deal with spatial area and utilizations the segments of pixels in the cover picture.Following invention is described in detail with the help of Figure 1 of sheet 1 showing cover image with histogram & RGB component, Figure 2 of sheet 1 illustrates the stego image with histogram & RGB component. 600 600 £00 , 400 20: 200 2fl 200 00 0 v0 20 40 0 100 200 0 200 400 0 2M 20U0 100_______ 101 102 103 104 Figure1I 600 600 600[~ 40400 400 400 20: 200 200 00 0 0 20 40 0 100 200 0 200 400 0 m 0a0 0 105_______ 101 102 103 104 Figure 2

Description

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A METHOD FOR DATA SECURITY USING VIRTUAL KEY REPLACEMENT IN IMAGE STEGANOGRAPHY

Technical field of invention:

[001] Present invention in general relates to data security and more specifically to a method for data security using virtual key replacement method in image steganography.

Background of the invention:

[002] The background information herein below relates to the present disclosure but is not necessarily prior art.

[003] Security and data hiding is a critical issue with almost all aspects of computer use. Storage media, such as hard disk drives attached to computers, contain valuable information, which is vulnerable to data theft. A great deal of money and effort is being applied to guarding personal, corporate, and government security information.

[004] As portable memory storage devices have become smaller, easier to lose, more ubiquitous, cheaper, and larger in memory capacity, they have come to pose extraordinary security problems. It is now possible to download massive amounts of information '0 surreptitiously into portable memory storage devices, such as universal serial bus flash and micro drives, cellphones, camcorders, digital cameras, iPODs, MP3/4 players, smart phones, palm and laptop computers, gaming equipment, authenticators, tokens (containing memory) in general, a mass storage device (MSD).

[005] More specifically, there are millions of MSDs being used for backup, transfer, intermediate storage, and primary storage into which information can be easily downloaded from a computer and carried away. The primary purpose of any MSD is to store and retrieve "portable content," which is data and information tied to a particular owner not a particular computer.

[006] The most common means of providing storage security is to authenticate the user with a computer-entered password. A password is validated against a MSD stored value. If a match occurs, the drive will open. Or, the password itself is used as the encryption key to encrypt/decrypt data stored to the MSD.

[007] For drives that support on-the-fly encryption, the encryption key is often stored on the media in an encrypted form. Since the encryption key is stored on the media, it becomes readily available to those willing to circumvent the standard interface and read the media directly. Thus, a password is used as the key to encrypt the encryption key.

[008] For self-authenticating drives, their authentication sub-system is responsible for maintaining security. There is no dependency on a host computer to which it is connected. Thus, a password cannot (or need not) be sent from the host in order to unlock the MSD. In fact, the encryption key no longer needs to be stored on the media. The authentication subsystem becomes the means for managing encryption keys.

[009] Data Hiding is the study of concealing information into harmless questions to such a degree, to the point that the nearness of the shrouded information stays intangible to an enemy. Hiding the data into cover image have differed procedures of usage created after some time. Insurance of the concealed data from an enemy is the most imperative objective of data hiding and henceforth clearly the security of a steganography framework will '0 increment if the image quality stays unintelligible to an assailant regardless of whether he holds information about the implanting technique.

[0010] Thus, a need still remains for improved security or hiding data. In view of the ever increasing commercial competitive pressures, along with growing consumer expectations and the diminishing opportunities for meaningful product differentiation in the marketplace, it is critical that answers be found for these problems. Additionally, the need to reduce costs, improve efficiencies and performance, and meet competitive pressures, adds an even greater urgency to the critical necessity for finding answers to these problems.

[0011] Although various attempts are made before, for providing various data security methods and few of them are such as-US9813416B2 discloses data security system with encryption,CN106230851B discloses data security method and system based on block chain, US7054465B2 discloses data hiding method and system for embedding and extracting information in signals, CN1128535C discloses data hiding method and data extracting method, EP0935392B1 discloses data hiding method and system, W02000025203 discloses methods of digital steganography for multimedia data.

[0012] There exist many drawbacks in the existing method for data security. However, there is no known method that assists a user to secure data using virtual key replacement method in image steganography. So,there is a need to develop method for data security using virtual key replacement method in image steganography.

Objective of the invention

[0013] An objective of the present invention is to attempt to overcome the problems of the prior art and provide a method for data security using virtual key replacement method in image steganography.

[0014] In a preferred embodiment, the present invention provides a virtual key replacement method which consolidates the advantages of LSB & Compression techniques to serve improved safeguard to the picture regarding data embedding capacity.

[0015] It is therefore an object of the invention to provide immense payload including better image quality ware the fundamental attribute considering each & every picture data concealing framework.

[0016] These and other objects and characteristics of the present invention will become apparent from the further disclosure to be made in the detailed description given below.

Summary of the invention:

Accordingly following invention provides a method for data security using virtual key replacement method in image steganography.The proposed instruments deal with spatial area and utilizations the segments of pixels in the cover picture. Presentinvention chose pixel to hide the knowledge interested in the cover portrait. Most of strategy effectively distinguishes the information behind the picture. Because of this dread, proposed technique utilizes red, green and blue segment to conceal the information. By utilizing this approach it is extremely hard to recognize the information behind the picture. Each pixel in a picture comprises of red, green and blue components. Every segment is comprised of 8 Bits. By joining all we get 24 bits for a solitary pixel in a picture. On the off chance consider alpha channel at that point add up to bits progress toward becoming 32.Each pixel in a picture comprises of red, green and blue components.

Brief description of drawing:

[0017] This invention is described by way of example with reference to the following drawing where,

[0018] Figure 1 of sheet 1 illustratescover image with histogram & RGB component. Whereas, 100 denotes cover image, 101 denotes histogram of cover image, 102 denotes red component of cover image, 103 denotes green component of cover image, 104 denotes blue component of cover image.

[0019] Figure 2 of sheet lillustrates the stego image with histogram & RGB component. Where, 105denotes stego image.

[0020] In order that the manner in which the above-cited and other advantages and objects of the invention are obtained, a more particular description of the invention briefly described above will be referred, which are illustrated in the appended drawing. Understanding that these drawing depict only typical embodiment of the invention and therefore not to be considered limiting on its scope, the invention will be described with additional specificity and details through the use of the accompanying drawing.

Detailed description of the invention:

[0021] The present invention relates toa method for data security using virtual key replacement method in image steganography. Present invention proposesa virtual key replacement method which consolidates the advantages of LSB &compression techniques to serve improved safeguard to the picture regarding data embedding capacity.

[0022] The proposed instrument deals with spatial area and utilizations the segments of pixels in the cover picture.The present invention chose pixel to hide the knowledge interested in the cover portrait. Most of the strategy effectively distinguishing the information behind the picture. Because of this dread proposed technique utilize red, green and blue segment to conceal the information. By utilizing this approach it is extremely hard to recognize the information behind the picture.A black & white picture requires just 1 bit for every pixel as contrasted and 8 bits for every dark pixel or 24 bits for each shading pixel. The little memory or capacity prerequisite makes a paired picture a perfect configuration for digitizing, preparing, transmitting and filing expansive measure of day by day records whose substance are ordinarily high contrast in nature. Each pixel in a picture comprises of red, green and blue components. Every segment is comprised of 8 Bits. By joining all we get 24 bits for a solitary pixel in apicture. On the off chance consider alpha channel at that point add up to bits progress toward becoming 32.

'0 [0023] In proposed mechanism the first step is to identify the input image which is used to hide the data called as cover image. The input image is represented in the form of Equation 1. A = {Xij l 0 ! i< Ma,0<! jNa, x}-_________ (1) In the above equation A represent the input image which is termed as cover image. Xij shows pixels in an image. In the first step we have to pick any pixel for data hiding. The second step is representation of secret image.

S = {mi l0 < i< N,miE {Q'I-----(2) When we hide the data inside cover image then it can called as virtual image

S'={mi'|0:i<n',mi'{O0,1,2,...2K (3)

Once the pixel is identified we have to embedded message k-i M Y maK .j*- ------------------------------------ (4) j=0

After the identification of pixel we can hide the data and the pixel become stego pixel.

Xi = xi-xjmod 2 K+mi' ---------------- (5)

[0024] In the exemplary embodiment of present invention we have to select the component of pixel. The following adaptive configuration shows the working of selection of components present in a pixel. Pixel is also represented as picture element. Step1: Select input image. Step 2: Select picture element from input image. Step 3: Select master colour component of image consist of red, green & blue ingredients. Step 4: Select any components out of three. Step 5: if ((R + 32)>255) OR (R-32) <0), ((G + 32)>255) OR (G-32) <0), ((B + 32)>255) OR (B-32) <0), then cast off picture ingredients else replace its 5 LSB side bits with data bits. Step 6: Repeat step 4 to 5 until all sentinel pixel region not scanned. Step 7: Stop

[0025] In the preferred embodiment, we have to convert datain the form of binary and save '0 the data behind master colour components. Once the Component is identified we have to generate the key mapping table.

Adaptive configuration for identification and conversion of key into binary for creation of key file

Step 1: Select input image (I) Step 2: Input secret data Step 3: Convert secret data to binary (SD) Step 4: Select master pixel (Mp) Step 5: Convert master pixel to binary Step 6: For i=1 to length (SD Binary)

Step 7: Bit Bi = SD Binary (i) Step 8: For i=0 to 8 Step 7: if Bi ==Mp(i)

Step 8: Add i to key file Step 9: Save key

Adaptive configuration for data compression of key file Step 1: Input key file Step 2: for I= 1 to 2 Step 3: Cluster key file with length (c)= i Step 4: Find c into the key Step 5: If frequency ( c ) >= 2 Step 6: replace c with single character that is A-Z, a-z etc Step 7: End Step 8: i = i - 1 Step 7: Save key mapping table.

[0026] Yet in the embodiment, assume we select baboon image as input image. In the wake of choosing the info picture we need to separate the RGB part on picture to choose the master colour component in a picture as we utilized this component to conceal information. Amid the extraction of RGB segment distinguish the position of pixel as for X, Y hub and convert '0 the pixel esteem into binary format. Assume at 0 area, the situation of X hub is 00000000, position of Y hub 00000000. On this Axis consider the estimation of red Pixel is 108, Green 101 and blue 49. We get this incentive after extraction of RGB segment from input image. Convert this RGB segment into binary configuration according to calculation. At that point the estimation of red, green and blue segment which is at (0,0) area is speak to by 01101100,01100101,00110001 individually.

[0027] In a similar way need to recognize and convert each pixel into the paired configuration. When we extricate the whole pixel in the binary format select the mystery information that expected to hole up behind the picture. Consider mystery information is "Hello there this is mahipbartere" and the length of the text is 26.Now mystery informationconvert into Binary organization.

010010000110100100100000011101000110100001101001011100110010000001101001011 100110010000001001101011000010110100001101001011100000010000001000010011000 0101110010011101000110010101110010011001010000110100001010.

[0028] Select master colour component which is in binary format and mystery content which is likewise in binary format. The master colour component is speak as 200000010000000000900101101082010100103500100011. This is lord shading segment as for X,Y hub alongside RGB part. The supplanting of pixel is finished with the assistance of master table. Table 1 demonstrates master table.

Secret Character Position in Secret Positionin master 0 1 1 1 2 7 0 3 1 0 4 1 1 5 7 0 6 1 0 7 1 0 8 1 0 9 1 1 10 7 1 11 7 0 12 1 1 13 7 0 14 1 0 15 1 Table 1: Master Table

[0029] Supplant mystery character with its particular position esteem. After the procedure of supplanting of information bit with its position in view of the position 171171111771711711711111177717111771711117717117177711771171111117717117177 711771171111117117717177111171771711117717117177711111171111117111171177111 1717771171177717111771171717771171177117171111771711117171. This is the key acquired from master table. The above key is got from key substitution table. The length of key is expansive. As the span of key is huge we pack the key. The key will be compacted in view of the key length. Consider key length as 5.The key substitution table is appeared in table 2

Segment Replace Original Compress Compression Length Segment Length Frequency Char Length Length Ratio Reduction 17117 5 9 A 208 172 0.8269231 36 11117 5 11 B 172 128 0.744186 44 11711 5 3 C 128 116 0.90625 12 77171 5 2 D 116 108 0.9310345 8 11771 5 2 E 108 100 0.9259259 8 7B7A1 5 2 F 100 92 0.92 8 77711 5 3 G 92 80 0.8695652 12 111A7 5 2 H 80 72 0.9 8 17177 5 2 1 72 64 0.8888889 8 G77C 4 2 J 64 58 0.90625 6 B177 4 2 K 58 52 0.8965517 6 717B 4 2 L 52 46 0.8846154 6 B7A 3 2 M 46 42 0.9130435 4 71A 3 2 N 42 38 0.9047619 4

Table 2: Key Replacement Table

AMCBDEFJM1JHIK1FGB11BHKNDE17IN711LL171 this is packed key. In this virtual stenography just utilized the ace shading part of unique Input picture and its individual position. It implies that we not conceal any information behind the picture rather done virtual stegnography. The nature of picture is kept up. From the above table it is seen that the key is getting packed up to 90 percent of unique key. This is information concealing procedure. For recover the information from the picture the main information requires is ace table which utilized as a substitution in light of pixel position and its esteem. Table 3 demonstrates the supplanting of fragment with character. Segment Replace Character 17117 A 11117 B 11711 C 77171 D 11771 E 7B7A1 F 77711 G 111A7 H 17177 I G77C J B177 K 717B L B7A M 71A N

Table 3: Segment Table By doing the reverse process we get the original data. The input image that is used as a cover representation is exposed in figure 1. It displays cover image with histogram(Visual Interpretation). The entropy of input image is 7.702, mean of image is 127.28, standard deviation of image is 52.56, pure height is 225, and pure width is 675.

[0030] Data Covering Capacity: The Maximal load of data can hide behind aimage it is represented by its data covering capacity labelled as hiding capacity. It is represented by two different ways; (I) greatest concealing limit, and (ii) bit-rate. The greatest concealing limit is the most extreme measure of information that can be covered up in the picture. It tends to be spoken to in the form of one or else zero, 8 bits or by 1024 bytes. The extreme number of bits that is concealed per picture element called as Bit Rate. It is regularly named as bits per pixel (bpp). For instance think about a 128x128 picture. At most on the off chance that it can stow away 18678 bits of information then the greatest concealing limit is 18678 bits. Whenever spoke to in bpp it is 18678 partitioned by 16384 which is equivalent to 1.14 bpp. On the off chance that the concealing limit is bigger than the steganography system is better.

[0031] Whatever the changes occurred in cover image after data hiding is measured with '0 different parameters. The deviation in the original image as compared to stego image is represented by MSE [18] in equation 6. 1 2 MSE=- (X,-X) m ------------------ (6)

Where m= Total Pixel in an Image.

Xi= Original Input Image.

X= Stego Image.

[0032] Sometimes it may be possible as in method the divergence among the input Image &Stego Image is Zero then we go for Root Mean Square Error which is represented as root of Equation 6[18]. Equation for finding RMSE value is shown in equation 7.

RMSE= (X--------------(7)

[0033] Peak signal noise ratio is quantify of alteration in the stego-image. It is enumerated by means of equation 8. It is considered that if the rate of Peak Signal Noise Ratio is high then slighter alteration. It is experimental that if the rate of Peak Signal Noise Ratio is diminished than 30dB then it is not examined because the quantity of alteration is more.40 dB measured as well. In the mid of 30 & 40dB can be satisfactory. To check the superiority of Stego Image (Changes occurred in Original Input Image after Data Hiding) is assess with PSNR. The superiority of stego image is based on PSNR value, which is estimated with the help of Equation 8.

P2 PSNR = 10* log10( ) ------------- (8) MSE

Where

P = Maximum Change in the Quality of Input Image.

[0034] Noise Visibility Function is defined as HVS is less delicate toward changes that happen in complex regions when contrasted with smooth territories. At the end of the day, changes in the dim estimations of pixels situated in smooth territories of a picture are all the more effortlessly seen by human eye.The NVS function is represented by equation 9.

NVF=1 1(y

Where o7 = Local variance of Image with respect to its Co ordinates (x, y).

The Weighted PSNR Value is calculated with the help of PSNR & NVF. WPSNR is used to enhance the visual nature of the decoded pictures. With the help of Equation 10 we calculate WPSNR.

WPSNR =10 *logo( R )2 (10 RMSE * NVF ~~

The closeness between the Input picture and the stego-picture is given by correlation. The correlation is shown by r. It is estimated utilizing (11).

Z(X-,)*(Y-Y) N --(11) (X- (y-_mY)2 n)a N N

Where X & Y =Component of Input Original &Stego Image.

X &Y = Average number of Pixel used for Data Hiding in Original &Stego Image. N = Total Number of Pixel in Original &Stego Image.

[0035] When we hide the data behind input image the image gets converted into Data Hided Image. To check the characteristics of picture is accessed by Universal Image Quality [19, 20]. It is shown with the help of equation 12, 13, 14,15,16,17 respectively.

(± ) )( ----------------- (12)

1 "

m -- ------------------------- (13)

Y=- - - - - - - - - - -Y14 1

= S-1 i= $(X -X) ------------ (15)

2 S= 11 (Y - Y)2 m- 1= ------------ (16)

1 X -X)(Y -Y) M-1 --(17) Where

X & Y= Average Value of Input Image & Data Hided Image.

a2&C y z = Deviation Factor of Input Image & Data Hided Image.

u,= measure of "linear dependence" betweenInput Image & Data Hided Image.

[0036] Measuring Quality of Image

When data is secrete in input cover image, quality of Image is getting degraded it means distortion occurs in image is serve by PSNR. For calculating the PSNR value first we have to calculate MSE value. MSE is represented by equation 6.Higher the PSNR value lowers the degradation of image and vice versa. If we consider the size of image is 32 X 32 it means it can hide 8192 bits and for 100 X 100 the hiding capacity is 80000 bits.

Payload Size PSNR dB

Baboon Tiffany Peppers F16 32 X32 99 99 99 99 60 X60 99 99 99 99 64 X64 99 99 99 99 80X80 99 99 99 99 100 X 100 99 99 99 99 Average 99 Table 4: Measure Image quality of stego image

The outcomes in Table 4 demonstrate that virtual key replacement technique tested with various cover images and diverse picture size delivers high Peak Signal to Noise Ratio (PSNR). Proposed scheme gives PSNR value of 99dB which is greater than 40dB. Therefore, the projected instrument shows immense devotion stego picture through immaterial noticeable twisting.

[0037] The many features and advantages of the invention are apparent from the detailed specification, and thus, it is intended by the appended claims to cover all such features and advantages of the invention which fall within the true spirit and scope of the invention. Further, since numerous modifications and variations will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation illustrated and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.

Editorial Note 2020104195 There is 1 page of Claims only.

Claims (3)

THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS:

1. A method for data security using virtual key replacement in image steganography which consolidates the advantages of LSB and compression techniques to serve improved safeguard to the picture regarding data embedding capacity, characterized in that;

red, green and blue segment is utilized to conceal the information,

a black and white picture requires just 1 bit for every pixel as contrasted and 8 bits for every dark pixel or 24 bits for each shading pixel;

wherein a little memory or capacity prerequisite makes a paired picture a perfect configuration for digitizing, preparing, transmitting and filing expansive measure of day by day records whose substance are ordinarily high contrast in nature.

2. The method as claimed in claim 1 wherein a first step is to identify the input image which is used to hide the data and wherein user have to select the component of pixel; comprises following steps; Select input image; Select picture element from input image. Select master colour component of image consist of red, green & blue ingredients; Select any components out of three; if ((R + 32)>255) OR (R-32) <0), ((G + 32)>255) OR (G-32) <0), ((B + 32)>255) OR (B 32)<0), then cast off picture ingredients else replace its 5 LSB side bits with data bits; Repeat step 4 to 5 until all sentinel pixel region not scanned; Stop.

3. The method as claimed in claim 1 wherein user have to convert data in the form of binary and save the data behind master colour components, once the component is identified user have to generate the key mapping table.