Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Self-adaptive watermark embedding method based on partial quality estimation

A technology for quality evaluation and watermark embedding, applied in instrumentation, calculation, image data processing, etc., can solve problems such as inflexible signal quality and reduced watermark robustness

Active Publication Date: 2006-10-11
BEIJING FOUNDER APABI TECH +1
View PDF4 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

In many cases, a global quality index cannot accurately reflect the local quality of the signal, such as a large picture or a long piece of music. At the same time, it is not flexible to adjust the local signal quality. In order to obtain all local Watermark imperceptibility, a sufficiently small global adjustment factor must be used, thus reducing watermark robustness
Although some digital watermarking methods are based on blocks, the evaluation of signal quality still uses a global index, and the above problems still exist

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
  • Self-adaptive watermark embedding method based on partial quality estimation
  • Self-adaptive watermark embedding method based on partial quality estimation
  • Self-adaptive watermark embedding method based on partial quality estimation

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0049] An adaptive watermark embedding method based on local quality evaluation, comprising the following steps:

[0050] (1) Assume the original signal X o =(x ij} M×N is an image, such as the typical "chili pepper" image in this example. The information M to be embedded is 0 or 1. In this embodiment, a random number generator is used and a large integer K is selected as a seed to generate an independent and identically distributed Gaussian sequence {w ij} M×N , if M=1, take W={w ij} M×N As the watermark signal, otherwise take W={-w ij} M×N As a watermark signal, it is assumed here without loss of generality that the dimension of the watermark signal is consistent with the carrier signal. In order to ensure the security of the watermark signal, the key K of the watermark should be kept absolutely secret.

[0051] (2) Next, the image X o All pixels of , are divided into p non-overlapping blocks according to their spatial positions, denoted by X o =X 1 ‖X 2 ‖…‖X ...

Embodiment 2

[0099] The difference from Example 1 is that

[0100] The original signal X of step (1) o ={x ij} M×N is the inverted frequency coefficient of the "Lena" image transformed by 8×8 block DCT, the size is 240×240, and the information M to be embedded is 0;

[0101] In step (2), the size of the sub-block is 24×24, so both the carrier signal and the watermark signal are divided into 10×10 sub-blocks;

[0102] In step (3), the Watson perceptual model based on 8×8 block DCT transform is used to evaluate the local quality of the signal, and the acceptable perceptual quality index t on each block is set. 1 =t 2 =…=t p = 0.3.

[0103] In step (4), first use the Watson model to obtain the maximum invisible modification of each frequency point, denoted as D={d ij} M×N , and then divide D into 10×10 sub-blocks according to the method of step (2), and denote the kth block as D k , then in each subblock X k Embed the corresponding watermark block W k , using the following embeddin...

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 self-adapting watermark embedding method, based on local quality evaluation, belonging to the digital watermark technique, while present watermark technique will cause distortion, the embedded watermark technique adjusts the strength of water mark according to one global quality index, without considering the local character of signal, and for confirming local signal quality, the global watermark strength will be reduced to decrease robustness. The invention blocked evaluates the quality of signal, and self-adapting adjusts the embedded strength of watermark in each block according to the local distortion condition. With said invention, the embedded watermark can fully utilize the local character of signal, to improve the robustness of watermark and attain better local unknown ability.

Description

technical field [0001] The invention belongs to the technical field of digital watermarking, and in particular relates to an adaptive watermark embedding method based on local quality evaluation. Background technique [0002] The past decade has seen an explosion in the use and distribution of digital media information. With the help of the Internet, people can easily publish and obtain various digital information, including images, audio, video and text, as well as many online services. But at the same time, piracy has become easier. Unrestricted copying and uncontrollable transmission make digital content copyrightless. The management and protection of digital content has become an urgent problem to be solved in the industry. [0003] Digital watermarking is an emerging copyright protection technology. It studies how to hide a certain amount of additional information in the original data, such as the ownership of the work, the right to use or the company's logo, etc., a...

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
IPC IPC(8): G06T1/00
Inventor 朱新山汤帜
Owner BEIJING FOUNDER APABI TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products