Md. Asikuzzaman

Imperceptible and Robust Blind Video Watermarking Using Chrominance Embedding: A Set of Approaches in the DT CWT Domain

Illegal distribution of a digital movie is a significant threat to the film industries. With the advent of high-speed broadband Internet access, a pirated copy of a digital video can be easily distributed to a global audience. Digital video watermarking is a possible means of limiting this type of digital distribution. In existing watermarking methods, the watermark is usually embedded into the luminance channel of a video frame, which affects imperceptibility. In addition, none of the existing techniques are robust to the combination of commonly used attacks, such as compression, upscaling, rotation, cropping, downscaling in resolution, frame rate conversion, and camcording. In this paper, we initially propose a basic blind digital video watermarking algorithm, where the watermark is embedded into one level of the dual-tree complex wavelet transform of the chrominance channel to provide high quality watermarked video and extracted using the same key that was used for embedding. This algorithm is robust to compression, upscaling, rotation, and cropping. An extension of this method extracts the watermark from any level(s) of the dual-tree complex wavelet transform depending on the resolution of the downscaled version of the watermarked frame rather than only from the embedding level to survive downscaling to an arbitrary resolution. Finally, the watermark of a frame is extracted from the information of that frame without using the key that was used during watermark embedding to provide robustness to temporal synchronization attacks, such as frame rate conversion. This scheme is also robust to compression, camcording, watermark estimation remodulation, temporal frame averaging, multiple watermark embedding, downscaling in resolution, and other geometric attacks, such as upscaling, rotation, and cropping.

A Blind Digital Video Watermarking Scheme with Enhanced Robustness to Geometric Distortion

Unauthorized redistribution of a movie is a common threat to digital media that can be prevented by digital video watermarking. The watermark is commonly embedded into the luminance (Y) component of a video frame. The chrominance (U) component supports more distortion than the Y component without being perceived by human eyes. Thus, in our proposed approach, the watermark is embedded into the U component in each frame of a video sequence using the dual-tree complex wavelet transform (DT CWT). This approach aims to provide perceptually invisible high quality watermarked video. The watermark detection is performed without using the original video content, i.e., the watermark extraction is blind. The proposed scheme is robust against different geometrical attacks such as scaling, cropping and rotation as well as lossy compression.

An Overview of Digital Video Watermarking

The illegal distribution of a digital movie is a common and significant threat to the film industry. With the advent of high-speed broadband Internet access, a pirated copy of a digital video can now be easily distributed to a global audience. A possible means of limiting this type of digital theft is digital video watermarking whereby additional information, called a watermark, is embedded in the host video. This watermark can be extracted at the decoder and used to determine whether the video content is watermarked. This paper presents a review of the digital video watermarking techniques in which their applications, challenges, and important properties are discussed, and categorizes them based on the domain in which they embed the watermark. It then provides an overview of a few emerging innovative solutions using watermarks. Protecting a 3D video by watermarking is an emerging area of research. The relevant 3D video watermarking techniques in the literature are classified based on the image-based representations of a 3D video in stereoscopic, depth-image-based rendering, and multi-view video watermarking. We discuss each technique, and then present a survey of the literature. Finally, we provide a summary of this paper and propose some future research directions.

3D Mapping for Visualization of Rigid Structures: A Review and Comparative Study

In this review, we discuss state-of-the-art developments in 3D models for small and rigid structures. This includes the pros and cons of cutting-edge range cameras used as active 3D scanners, while also considering passive image reconstruction schemes by means of the well-known structure-from-motion (SfM) algorithms. Furthermore, we discuss the issue of how data fusion algorithms can be used to optimally fuse 2D contour information onto 3D models for several different applications. Considering the benefits of 3D range sensors, we also review current trends in optimum data fusion of point clouds from 3D range sensors. We present the benefits and the limitations of each algorithm against various design considerations. To highlight the pros and cons, we also perform a comparative study of the performance of a 3D range sensor, represented by an iPad structure sensor, with respect to the well-known SfM software packages, namely, Bundler, Microsoft PhotoSynth, Agisoft PhotoScan, and Smart3DCapture. Last, we highlight several research opportunities and potential research challenges associated with each technique.

Robust DT CWT-Based DIBR 3D Video Watermarking Using Chrominance Embedding

The popularity of 3D video is increasing daily due to the availability of low-cost 3D televisions and high-speed Internet access. However, currently the contents of 3D video can be distributed illegally without any protection. For views generated using a depth-image-based rendering technique, not only the left and right views can be distributed as 3D content, but also the center, left, or right views individually as 2D content. As digital video watermarking is a possible way of protecting these views from unauthorized distribution, in this paper, we propose a digital watermarking method for depth-image-based rendered 3D video. In this method, the watermark is embedded in both of the chrominance channels of a YUV representation of the center view using the dual-tree complex wavelet transform. Then, the left and right views are generated from the watermarked center view and depth map using a depth-image based rendering technique. Finally, the watermark can be extracted from the center, left, and right views in a blind fashion without using the original unwatermarked center, left, or right views. This watermark is robust to geometric distortions, such as upscaling, rotation and cropping, downscaling to an arbitrary resolution, and the most common video distortions, including lossy compression and additive noise. Due to the approximate shift invariance characteristic of the dual-tree complex wavelet transform, the technique is robust against distortions in the left and right views generated using depth-image based rendering. The proposed method can also survive baseline distance adjustment and both 2D and 3D camcording.

A blind watermarking scheme for depth-image-based rendered 3D video using the dual-tree complex wavelet transform

The amount of unauthorized distribution of 3D video is increasing day by day due to the availability of high speed Internet and low cost 3D TV. Note that, not only both left and right views generated using depth-image-based rendering can be distributed as 3D content but also the centre, left or right view individually as 2D content. Video watermarking is a possible way to protect this type of illegal distribution. In this paper, we propose a digital watermarking method for depth-image-based rendered 3D video to protect each centre, left, and right view. In this method, the watermark is embedded into the centre view using the dual-tree complex wavelet transform. At the receiver, the left and the right views are generated from the centre view and the depth map using depth-image-based rendering. Finally, we extract the watermark from the centre, left and right views in a blind fashion. This scheme is robust to the most common video distortions which include geometric attacks such as scaling, rotation and cropping as well as lossy JPEG compression and additive noise.

A Blind and Robust Video Watermarking Scheme Using Chrominance Embedding

Piracy of a digital movie is a significant threat for movie studios and producers. Digital video watermarking is an important technique that can be used to protect the content. In existing watermarking algorithms, robustness to several attacks of the watermark has been improved. However, none of the existing techniques are robust to a combination of the common geometric distortions of scaling, rotation, and cropping with other attacks. In this paper, we propose a blind video watermarking algorithm where the watermark is embedded into both chrominance channels using a dual-tree complex wavelet transform. Embedding the watermark into the chrominance channels maintains the original video quality and the dual-tree complex wavelet transform ensures the robustness to geometric attacks due to its shift invariance characteristics. The watermark is extracted using the information from a single frame without using the original frame which makes this approach robust to temporal synchronization attacks such as frame dropping and frame rate change. This approach is also robust to downscaling in arbitrary resolution, aspect ratio change, compression, and camcording.

A blind and robust video watermarking scheme in the DT CWT and SVD domain

The piracy of a digital movie is a significant problem for movie studios and producers but can be prevented by digital video watermarking. In existing watermarking algorithms, robustness to several attacks on the watermark has been improved. However, none of these existing techniques are robust to a combination of the common geometric distortions of scaling, rotation, cropping and downscaling in resolution with other attacks such as video compression. In this paper, a blind video watermarking algorithm is proposed where the watermark is embedded in the singular values of the dual-tree complex wavelet transform coefficients of the chrominance channel. As distortion in the chrominance channel is less sensitive to the human eye, the original video quality is maintained. The singular value decomposition is used due to the good stability of its singular values while the approximate shift invariance characteristic of the dual-tree complex wavelet transform ensures robustness to geometric attacks. The proposed scheme is robust to upscaling, rotation, cropping, downscaling to an arbitrary resolution, aspect ratio change, noise addition and H.264/AVC compression.

Real Time Prototype to Measure Structural Acceleration and Tilt of High-Rise Building

Smart sensor is the new invention applying to detect the damage of the high-rise civil building structural health. Sensor technology offers new opportunities to advance monitoring for civil large building infrastructure health and maintenance by providing relevant information regarding the condition of high-rise building structural strength at a light price and greater bulk than traditional monitoring tactics. The aim of this article is to validate the MEMS accelerometer sensor to measure vibration and tilt of the high-rise civil building infrastructures. The experimental result shows that the propose prototype has been successfully measured high-rise building vibration and tilt sensing information. Streszczenie. W artykule opisano mozliwości zastosowania czujnikow przyśpieszenia typu MEMS do pomiaru wibracji i odchylenia konstrukcji budynkow. Przedstawione wyniki badan eksperymentalnych potwierdzają przydatnośc tych czujnikow szczegolnie w sytuacjach duzych zagrozen. Prototyp systemu pomiarowego do badania wibracji i odchylenia konstrukcji budynkow.

3D kinematic measurement of human movement using low cost fish-eye cameras

3D motion capture is difficult when the capturing is performed in an outdoor environment without controlled surroundings. In this paper, we propose a new approach of using two ordinary cameras arranged in a special stereoscopic configuration and passive markers on a subject’s body to reconstruct the motion of the subject. Firstly for each frame of the video, an adaptive thresholding algorithm is applied for extracting the markers on the subject’s body. Once the markers are extracted, an algorithm for matching corresponding markers in each frame is applied. Zhang’s planar calibration method is used to calibrate the two cameras. As the cameras use the fisheye lens, they cannot be well estimated using a pinhole camera model which makes it difficult to estimate the depth information. In this work, to restore the 3D coordinates we use a unique calibration method for fisheye lenses. The accuracy of the 3D coordinate reconstruction is evaluated by comparing with results from a commercially available Vicon motion capture system.