Method for embedding and extracting watermark in digital image

A watermark embedding, digital image technology, applied in the field of information hiding and image steganography, can solve the problem of not considering the influence of the local noise of the pixel value watermark image, and achieve the effect of low noise and good resistance to steganalysis.

Inactive Publication Date: 2012-03-07
PEKING UNIV
View PDF0 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The problem with the second prior art is: when the parity between the watermark information and the pixel value is different, randomly add 1 or subtract 1 to the pixel value, regardless of the size of the surrounding pixel values, that is, the direction of change of the pixel value is not considered. The influence of image local noise size

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for embedding and extracting watermark in digital image
  • Method for embedding and extracting watermark in digital image
  • Method for embedding and extracting watermark in digital image

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0077] Embodiment 1, the method for embedding a watermark in a digital image:

[0078] 1. Obtain such as Figure 5 The grayscale image "Lena" shown has a size of 512x512.

[0079] 2. Obtain the watermark bit string composed of 0 and 1 with a length of 512×512-1=262 143:

[0080] W=(W 1 , W 2 ,...,W 262143 ).

[0081] 3. Sort all the pixels of the grayscale image from left to right and then from top to bottom, and obtain the first 262143 pixels as embedded pixels, thus obtaining the sequence of pixel values

[0082] x 1 , X 2 ,...,X 262143

[0083] 4. Denoise the grayscale image with linear mean filtering, sort all the pixels of the grayscale image after denoising in the same way as the original image, and obtain the first 262143 pixels as the embedded reference point, from which the denoised image can be obtained sequence of pixel values

[0084] D. 1 ,D 2 ,...,D 262143

[0085] 5. For i ∈ {1, 2, ..., 262 143}, according to the watermark signal W i Change the p...

Embodiment 2

[0095] Embodiment 2, the method for extracting watermark in digital image:

[0096] 1. Obtain such as Figure 4 The grayscale image with embedded watermark is shown, its size is 512×512.

[0097] 2. Extract the pixel value of the grayscale image in the same way as embedding the watermark, there are 262 143 values ​​in total, assuming that the pixel value of the i-th pixel is Y i , where i ∈ {1, 2, ..., 262 143}.

[0098] 3. Calculate the embedded watermark value W i =Y i mod 2.

[0099] 4. Combine the watermarks extracted from each pixel to obtain a final watermark bit string consisting of 0 and 1.

[0100] The process of extracting the watermark proposed by the embodiment of the present invention will be explained in more detail below for several different pixel values. Suppose we get a watermark image pixel value Y i =165, then the watermark value 1 can be extracted. And when we get a watermark image pixel value Y i =164 or 166, then the watermark value 0 can be ext...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses a method for embedding and extracting a watermark in a digital image, and belongs to the technical field of information hiding and image hidden writing. The watermark embedding method comprises the following steps of: de-noising a primary digital image to obtain a de-noised image; and then matching a binary watermark to be embedded and a pixel value of the primary digital image, and finally changing the pixel value of the primary image according to the pixel value of the corresponding de-noised image so as to realize watermark embedding. The watermark extracting methodcomprises a step of sequentially extracting lowest significance bits according to the acquired pixel value of the watermark image to acquire watermark information. Compared with the prior art, the noise of the watermark image is lower after the pixel value of each point is changed, and hidden writing analysis can be resisted better.

Description

technical field [0001] The invention belongs to the technical field of information hiding and image steganography, and in particular relates to a method for embedding and extracting watermarks in digital images. Background technique [0002] Information hiding is a new research hotspot in the field of information security. Information hiding includes secret-related data communication in an open network environment, intellectual property protection of digital products, authenticity identification of important documents and digital signatures, and post-disclosure of confidential documents. The source tracking of news provides reliable information security guarantee. Digital watermarking and image steganography are two branches of information hiding technology. [0003] Existing technology 1—least significant bit replacement: It is proposed to insert secret information into the least significant bit of the original image pixel value one by one pixel by pixel, which can ensure ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Patents(China)
IPC IPC(8): G06T1/00
Inventor 李晓龙王超亓文法杨斌
Owner PEKING UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products