Dong-Hyuck Im

Real-time video watermarking system on the compressed domain for high-definition video contents: Practical issues

Everyday, we encounter high-quality multimedia contents from HDTV broadcasting, DVD, and high-speed Internet services. These contents are, unhappily, processed and distributed without protection. This paper proposes a practical video watermarking technique on the compressed domain that is real-time and robust against video processing attacks. In particular, we focus on video processing that is commonly used in practice such as downscaling resolution, framerate changing, and transcoding. Most previous watermarking algorithms are unable to survive when these processings are strong or composite. We extract low frequency coefficients of frames in fast by partly decoding videos and apply a quantization index modulation scheme to embed and detect the watermark. On an Intel architecture computer, we implement a prototype system and measure performance against video processing attacks frequently occur in the real world. Simulation results show that our video watermarking system satisfies real-time requirements and is robust to protect the copyright of HD video contents.

Practical, Real-Time, and Robust Watermarking on the Spatial Domain for High-Definition Video Contents

Commercial markets employ digital right management (DRM) systems to protect valuable high-definition (HD) quality videos. DRM system uses watermarking to provide copyright protection and ownership authentication of multimedia contents. We propose a real-time video watermarking scheme for HD video in the uncompressed domain. Especially, our approach is in aspect of practical perspectives to satisfy perceptual quality, real-time processing, and robustness requirements. We simplify and optimize human visual system mask for real-time performance and also apply dithering technique for invisibility. Extensive experiments are performed to prove that the proposed scheme satisfies the invisibility, real-time processing, and robustness requirements against video processing attacks. We concentrate upon video processing attacks that commonly occur in HD quality videos to display on portable devices. These attacks include not only scaling and low bit-rate encoding, but also malicious attacks such as format conversion and frame rate change.

Color laser printer identification by analyzing statistical features on discrete wavelet transform

Color laser printers are nowadays abused to print or forge official documents and bills. Identifying color laser printers will be a step for media forensics. This paper presents a new method to identify color laser printers with printed color images. First, 39 noise features of color printed images are extracted from the statistical analysis of the HH sub-band on discrete wavelet transform. Then, these features are applied to train and classify the support vector machine for identifying the color laser printer. In the experiment, 9 models of 4 brands, Xerox, Konica, HP, Canon, are tested to classify the brand of color laser printer, the color toner, and the model of color laser printer. The results prove that the presented identification method performs well using the noise features of color printed images.

Electrophotographic printer identification by halftone texture analysis

Estimating printing source is applicable in many forensic situations. In this paper, we propose an electrophotographic printer identification scheme from its printed material, in which imperceptible halftone patterns are contained inherently. The halftone textures in each channel of CMYK domain are analyzed. We construct a histogram from angle values of linear features extracted by Hough transform. By averaging the histograms from multiple images, a printers reference pattern is identified. The soure printer is determined by a maximum correlation value between the reference patterns and the histogram of given image. Experiments are performed on 9,000 images made by 9 printers. The result supports that the presented scheme clearly recognizes different halftone textures.

A Practical Real-Time Video Watermarking Scheme Robust against Downscaling Attack

In this paper, we propose a practical real-time video watermarking scheme for downscaling attack. We embed watermark into an arbitrary size of a host video and extract it from the watermarked video under a preset false error rate. Both watermark embedding and extraction are done in the uncompressed domain. Also, blind detector is used (i.e., no original video needs during the detection). As our watermarking system uses a video coder and decoder according to a format of an input video, it can be applicable to DCT-based coding videos (e.g., MPEG-2) as well as MPEG-1 and MPEG-4. Moreover, for a practical use both embedder and detector are developed as directshow filters that make it easy to connect after another within directshow applications. The payload of this system is totally 192 bits. PSNR after embedding is around 45dB for the host video that ranges from QVGA to High Definition (HD) size. Finally, several experimental results prove that the proposed scheme has good robustness.

Implementation of real-time watermarking scheme for high-quality video

Digital watermarking for video helps protect the copyright of the video content. In most watermark applications, an embedding procedure should be built at low costs and the embedded watermarks should have robustness against various unintentional or malicious attacks. This paper addresses implementation issues for real-time watermark embedding scheme of High Definition(HD) resolution video on a personal computer. This paper provides some performance optimization guidelines and a simplified Human Visual System (HVS) method for fast and robust watermark embedding. Demonstration shows a real-time watermark embedding process including HD MPEG-2 video decoding, watermark embedding and displaying on an Intel architecture personal computer. Experimental results show optimized embedding performances and robustness against several malicious attacks commonly happened to videos. From the results, our implementation solution improved the embedding performance suitable for real-time watermark embedding for HD video.

Vector Watermarking Robust to Both Global and Local Geometrical Distortions

A blind watermarking algorithm for vector graphic images is presented. The algorithm is resilient to both global and local geometrical distortions. The polygonal line is represented by the wavelet descriptor. An additive watermarking scheme is used to embed the watermark by slightly modifying the wavelet descriptor, and that causes invisible distortions to the coordinates of the vertices. The invariant properties of the wavelet descriptor ensure that the presented algorithm is resilient against both global and local geometrical distortions. Using vector graphic images from contour maps, we demonstrate that the presented algorithm outperforms the algorithm based on the Fourier descriptor.

Error Concealment Technique of Satellite Imagery Transmission through Information Hiding

Imperfect transmission of satellite imagery results in the loss of image lines. This paper proposes a novel error concealment technique using LSB-based watermarking. We generate block description information and insert it into the LSB bit plane of the image. Missing lines after transmission are restored by extracting this block description information. Simulation results show outstanding performance of the proposed technique.

Real-Time watermark embedding for high resolution video watermarking

This paper addresses implementation issues for real-time watermark embedding scheme of High Definition(HD) resolution videos on personal computers. In most watermark applications, an embedding procedure should be built at low costs and at the same time the embedded watermarks should have robustness against signal and image processing as well as malicious attacks. This paper provides some performance optimization guidelines and a simplified Human Visual System (HVS) method for fast and robust watermark embedding. This work demonstrates a real-time watermark embedding process including HD MPEG-2 video decoding, watermark embedding and displaying on Intel architecture personal computers. Experimental results show optimized embedding performances and robustness against several malicious attacks commonly happened to videos.

Watermarking curves using 2D mesh spectral transform

This paper presents a robust watermarking method for curves that uses informed-detection. To embed watermarks, the presented algorithm parameterizes a curve using the B-spline model and acquires the control points of the B-spline model. For these control points, 2D mesh are created by applying Delaunay triangulation and then the mesh spectral analysis is performed to calculate the mesh spectral coefficients where watermark messages are embedded in a spread spectrum way. The watermarked coefficients are inversely transformed to the coordinates of the control points and the watermarked curve is reconstructed by calculating B-spline model with the control points. To detect the embedded watermark, we calculate the difference between the original and watermarked mesh spectral coefficients with the same process for embedding. By calculating correlation coefficients between the detected and candidate watermark, we decide which watermark was embedded.