Seok Kang

Image data embedding system for watermarking using Fresnel transform

Watermarking is a technique embedding hidden multimedia information imperceptibly, such as images and sounds. Generally, the original image is transformed and coded watermark data is embedded in frequency domain watermarking models. We propose a new data embedding method using the Fresnel transform. A watermark image is Fresnel-transformed and the intensity of the transformed pattern is embedded into the original image. Our watermarking model has the flexibility in data hiding. It is possible to embed watermarks in many different observable planes with various distance parameters of the Fresnel transform and all kinds of image models such as shape, letter and photo can be used as a watermark data. Using the Fresnel transform with various distance parameters, it is possible to get many channels for embedding. So our method can recover the weak point, having only one transform plane in DFT and DCT domain methods. The watermarking experiments were conducted to show the validity of the proposed method, and the results show that our method can provide multi frequency domains for embedding watermark.

An image watermarking technique using cellular automata transform

Watermarking is a technique embedding hidden multimedia information imperceptibly, such as images and sounds. Generally original image is transformed and coded watermark data is embedded in frequency domain watermarking models. In this paper, we propose a new data embedding method using cellular automata transform (CAT). An original image is CA-transformed and the watermark data is embedded into the coefficients of CA-transformed pattern. Our watermarking model has the flexibility in data hiding. It is possible to embed watermark pattern in many different CAT planes with different rule number parameters and CA bases class of CAT and all kinds of image models such as shape, letter and photo can be used as a watermark data. Using CAT with various rule number parameters, it is possible to get many channels for embedding. So our method can recover the weak point having only one transform plane in DFT and DCT domain methods. The watermarking experiments were conducted to show the validity of the proposed method, and the results show that our method can provide multi frequency domains for embedding watermark.

Digital image watermarking by Fresnel transform and its robustness

Watermarking is a technique embedding hidden multimedia information imperceptibly, such as images and sounds. Generally original image is transformed and coded watermark data is embedded in the frequency domain watermarking models. In this paper, we propose a new data embedding method using Fresnel transform. A watermark image is Fresnel-transformed and the intensity of transformed pattern is embedded into original image. Our watermarking model has the flexibility in data hiding. It is possible to embed watermark in many different observable planes with various distance parameters of Fresnel transform and all kinds of image models such as shape, letter and photo can be used as watermark data. Using Fresnel transform with various distance parameters, it is possible to get many channels for embedding. So our method can recover the weak point having only one transform plane in DFT and DCT domain methods. The watermarking experiments were conducted to show the validity of the proposed method, and the results show that our method can provide multi frequency domains for embedding watermark and have robustness against filtering and geometric transformation.

A multiple data embedding technique for DRM using Fresnel transform

Watermarking is one approach to address the problem about authority of multimedia data. The concept of digital watermarking is associated with the data-hiding technique known as steganography. Digital watermarking has been proposed as a way to identify the source, creator, owner, distributor, or authorized consumer of multimedia data. Recently, DRM has emerged for the purpose of more powerful and integrated management system of multimedia contents. On the contrary to the watermarking technique, in the DRM systems we need to embed more than one data. In past watermarking techniques, we could distinguish individual watermarks but it was impossible to separate them. In this paper, we propose a new multiple image data embedding method for DRM using Fresnel transform. Two watermark images are Fresnel-transformed as the real number and imaginary number data individually for Fresnel transform, and the values of difference between coefficients of a transformed pattern and their average are embedded into an original image. Our watermarking model allows flexibility in hiding the watermark. It is possible to get many embedding patterns from by using various distance parameters with Fresnel transform. Watermarking experiments have shown the validity of our watermarking technique and its robustness in resisting attacks

Morphing of 2-D models by Fresnel transform

A new morphing technique is proposed, where two two-dimensional (2-D) models are Fresnel-transformed and intensities of the transformed patterns are superposed and clipped, resulting in a blending pattern of two models. Since the Fresnel transform depends upon the distance parameter between the model and the Fresnel-transformed planes, the morphing process from one model to another is observed by changing the distance parameter. The morphing experiment was conducted using 2-D models, such as letters and simple figures by performing Fresnel transforms with 32/spl times/32 sampling points. Discussion is done by comparing the proposed morphing technique with a morphing technique using Fourier transform, where model spectra are superposed in the spectrum plane using a weighting factor to blend the spectra of both models proportional to the weighting factor, whereas phase functions are multiplied on the Fourier transforms of models in the Fresnel transform method.

TDX-10: a flexible switching architecture for ISDN

The switching system in the integrated services digital network (ISDN) supports the exchange of user information, which may be voice or data. Also the system provides the interworking facilities to communicate with existing networks until they are replaced by ISDN. The TDX-10 is an advanced switching system suitable for advanced networks, including ISDN. The author gives the architecture and ISDN design concepts of the TDX-10 switching system.<<ETX>>

An image data watermarking technique using the average of a Fresnel-transformed pattern

Watermarking is a technique embedding hidden information in multimedia data imperceptibly, such as image, video, audio and text data. Generally an original image is transformed and coded watermark data is embedded in frequency domain watermarking models. We propose a new image data embedding method using Fresnel transform. A watermark image is Fresnel-transformed and the values of difference between coefficients of a transformed pattern and their average are embedded into an original image. Our watermarking model allows flexibility in hiding the watermark. It is possible to get many embedding patterns from a single watermark image by using various distance parameters with the Fresnel transform. All kinds of image models, such as shapes, letters and photos, can be used as watermark data. Watermarking experiments have shown the validity of our watermarking technique and its robustness in resisting attacks.

Volume morphing by Fourier transform

We describe a new morphing technique using the Fourier transform. Two-dimensional (2-D) or three-dimensional (3-D) models are Fourier-transformed and the intensities of the transformed patterns are superposed and clipped, resulting in a blending pattern of two models. Morphing by the simple interpolation yields an interesting result between the models, but difficulty can arise if the models are composed of dominant higher frequency components. We therefore propose a new method, where the morphing of two models is done after dividing a higher-frequency dominant model into two lower-frequency dominant models. The morphing experiment was conducted to show the validity of the proposed methods using simple 2-D and 3-D models.