Digital Image Tracing by Sequential Multiple Watermarking(2011)

ABSTRACT:

The possibility of adding several watermarks to the same image would enable many interesting applications such as multimedia document tracing, data usage monitoring, and multiple property management. In this paper, we present a novel watermarking scheme, which allows inserting and reliably detecting multiple watermarks sequentially embedded into a digital image. The proposed method, based on elementary linear algebra, is asymmetric, secure under projection attack and robust against distortion due to basic operations such as storage, transmission, and format conversion.

Digital watermarking is a process for modifying physical or electronic media to embed a machine-readable code into the media. The media may be modified such that the embedded code is imperceptible or nearly imperceptible to the user, yet may be detected through an automated detection process. Most commonly, digital watermarking is applied to media signals such as images, audio signals, and video signals. However, it may also be applied to other types of media objects, including documents (e.g., through line, word or character shifting), software, multi-dimensional graphics models, and surface textures of objects.

Digital watermarking systems typically have two primary components: an encoder that embeds the watermark in a host media signal, and a decoder that detects and reads the embedded watermark from a signal suspected of containing a watermark (a suspect signal). The encoder embeds a watermark by altering the host media signal. The reading component analyzes a suspect signal to detect whether a watermark is present. In applications where the watermark encodes information, the reader extracts this information from the detected watermark.

Project Introduction

Digital watermarking is a process for modifying physical or electronic media to embed a machine-readable code into the media. The media may be modified such that the embedded code is imperceptible or nearly imperceptible to the user, yet may be detected through an automated detection process. Most commonly, digital watermarking is applied to media signals such as images, audio signals, and video signals. However, it may also be applied to other types of media objects, including documents (e.g., through line, word or character shifting), software, multi-dimensional graphics models, and surface textures of objects.

Digital watermarking systems typically have two primary components: an encoder that embeds the watermark in a host media signal, and a decoder that detects and reads the embedded watermark from a signal suspected of containing a watermark (a suspect signal). The encoder embeds a watermark by altering the host media signal. The reading component analyzes a suspect signal to detect whether a watermark is present. In applications where the watermark encodes information, the reader extracts this information from the detected watermark.

Several particular watermarking techniques have been developed. The reader is presumed to be familiar with the literature in this field. Particular techniques for embedding and detecting imperceptible watermarks in media signals are detailed in the assignee's co-pending application Ser. No. 09/503,881 and U.S. Pat. No. 6,122,403, which are hereby incorporated by reference.

Overview

The method operates on a watermarked image 100 that has been geometrically distorted, either intentionally or unintentionally. Before the method begins, a global synchronization method, such as those described in watermarking literature is used to compute an estimate of the affine geometric distortion of the image since being embedded with the digital watermark.

The method operates on small blocks of pixels within an image frame. To extract a watermark message from the block, a watermark reader first needs to determine the geometric distortion and compensate for it. The method described here attempts to provide a more accurate measure of the geometric distortion by refining the estimate of affine geometric distortion.

To accomplish this, the method applies the affine transform to the small block (102) using the estimated affine transform parameters (104). The method interpolates the image samples computed from the affine transform to compute image sample values at discrete sample locations within the transformed block. These interpolated sample values form a block of image data approximating a block in the watermarked image at the time of embedding. However, errors due to estimation and non-linear distortion remain.

Existing System

The existing system they are used single watermarking concept. In this concept overwriting applied only one time. So, it has some low security.

Proposed System

The proposed method, based on elementary linear algebra, is asymmetric, involving a private key for embedding and a public key for detection. Its robustness against standard image degradation operations has been extensively tested and its security under projection attack has also been proven even though the envisaged application refers to a collaborative environment, in which malicious attacks are not a critical aspect. Here we are providing multiple watermarking concepts, such as the sample image overwrite more than one time on the original image.

Modules and its Description

Modules:

1. Preprocessing

2. Resolution Hiding

3. Watermarking

4. Security providing

Module description:

1. Preprocessing

Color Enhancement, Improve the image quality, Size corrections, and noise removal.

Algorithm: Morphological Filters, Automatic Color Enhancement technique [ACE]

Input: Stills with low quality

Output: Quality stills.

2. Resolution Hiding

Reduce the resolution or hide the original images using sample images.

3. Watermarking

Implementing multiple watermarking concepts to provide security for the original images. For that we are going to generate random sample images with the same pixels.

Using these images we can overwrite on the original image and then we get a collapsed image.           

4. Security providing

Multiple watermark process will generate random keys for each and every image. Using these keys the reverse process will be done by receiver side.

SOFTWARE SPECIFICATION:-

OPERATING SYSTEM                   :  Windows XP Professional

FRONT END                                   :  Microsoft Visual Studio .Net 2010

CODING LANGUAGE                   :  C# .Net

HARDWARE SPECIFICATION:-

SYSTEM                                         :   Pentium III 700 MHz

HARD DISK                                   :   40 GB

MONITOR                                      :   15 VGA colour monitor

RAM                                                :   256MB