The Experts below are selected from a list of 5409 Experts worldwide ranked by ideXlab platform
Tae Jeong Kim - One of the best experts on this subject based on the ideXlab platform.
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Fast communication: A blind MPEG-2 video watermarking robust to Camcorder recording
Signal Processing, 2010Co-Authors: Dooseop Choi, Hyuk Choi, Tae Jeong KimAbstract:Based on the observation that low-frequency DCT coefficients of an image are less affected by geometric processings, we propose a new blind MPEG-2 video watermarking algorithm robust to Camcorder recording. The mean of the low-frequency DCT coefficients of the video is temporally modulated according to the information bits. To avoid watermark's drift into other frames, we embed watermarks only in the B-frames of MPEG-2 videos, which also allows minimal partial decoding and achieves efficiency. Experimental results show that the proposed scheme achieves high video quality and robustness to Camcorder recording and other attacks.
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Digital Video Watermarking Based on Histogram and Temporal Modulation and Robust to Camcorder Recording
2008 IEEE International Symposium on Signal Processing and Information Technology, 2008Co-Authors: Dooseop Choi, Hyuk Choi, Tae Jeong KimAbstract:This paper presents a blind digital video watermarking scheme, which is especially robust to Camcorder recording attacks and also to a variety of common video processing and geometric distortions. Using the fact that nearby frames of a video sequence are quite similar, the method embeds the watermark by temporal modulation of the frames. The watermark pattern used in modulation is generated based on the pixel-value histogram, which makes extraction free from geometric synchronization. To make it imperceptible, the watermark is adjusted according roughly to the Human Visual System. The experimental results demonstrate the robustness of the proposed method to Camcorder recording attacks also involving geometric distortions and other video processing attacks such as MPEG and other compressions.
Wolfgang Effelsberg - One of the best experts on this subject based on the ideXlab platform.
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CamMark: Analyzing, Modeling, and Simulating Artifacts in Camcorder Copies
ACM Transactions on Multimedia Computing Communications and Applications, 2015Co-Authors: Philipp Schaber, Stephan Kopf, Christoph Wesch, Sina Wetzel, Tyler Ballast, Wolfgang EffelsbergAbstract:To support the development of any system that includes the generation and evaluation of Camcorder copies, as well as to provide a common benchmark for robustness against Camcorder copies, we present a tool to simulate digital video re-acquisition using a digital video camera. By resampling each video frame, we simulate the typical artifacts occurring in a Camcorder copy: geometric modifications (aspect ratio changes, cropping, perspective and lens distortion), temporal sampling artifacts (due to different frame rates, shutter speeds, rolling shutters, or playback), spatial and color subsampling (rescaling, filtering, Bayer color filter array), and processing steps (automatic gain control, automatic white balance). We also support the simulation of camera movement (e.g., a hand-held camera) and background insertion. Furthermore, we allow for an easy setup and calibration of all the simulated artifacts, using sample/reference pairs of images and videos. Specifically temporal subsampling effects are analyzed in detail to create realistic frame blending artifacts in the simulated copies. We carefully evaluated our entire Camcorder simulation system and found that the models we developed describe and match the real artifacts quite well.
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cammark a Camcorder copy simulation as watermarking benchmark for digital video
ACM SIGMM Conference on Multimedia Systems, 2014Co-Authors: Philipp Schaber, Stephan Kopf, Christoph Wesch, Wolfgang EffelsbergAbstract:In 1998, Petitcolas et al. proposed StirMark [14] as a benchmark for image watermarking schemes. The main idea was to introduce a re-sampling process that mimics the analog process of printing and scanning a watermarked image. For digital video, the corresponding concept is a Camcorder copy, where a video displayed on a screen is (digitally) recorded using a video camera. As most commercial video streaming systems (VOD, IPTV) and offline distribution (Blu-ray, HDDs for cinemas) are strongly protected by means of DRM, filming a display is actually a relevant use case and a requirement for robust video watermarking systems to survive. We therefore present a tool to simulate content re-acquisition with a Camcorder. Our goal is to support watermark development by enabling automated test cases for such Camcorder copy attacks, as well as to provide a benchmark for robust video watermarking. Manually creating Camcorder copies is a cumbersome process, and even more problematic, it is hardly reproducible with the same setup. By re-sampling each video frame, we simulate the typical artifacts of a Camcorder copy: geometric modifications (aspect ratio changes, cropping, perspective and lens distortion), temporal modifications (unsynchronized frame rates and the resulting frame blending), sub-sampling (rescaling, filtering, Bayer color array filter), and histogram changes (AGC, AWB). We also support simulating camera movement (e.g., a hand-held camera) and background insertion.
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MMSys - CamMark: a Camcorder copy simulation as watermarking benchmark for digital video
Proceedings of the 5th ACM Multimedia Systems Conference on - MMSys '14, 2014Co-Authors: Philipp Schaber, Stephan Kopf, Christoph Wesch, Wolfgang EffelsbergAbstract:In 1998, Petitcolas et al. proposed StirMark [14] as a benchmark for image watermarking schemes. The main idea was to introduce a re-sampling process that mimics the analog process of printing and scanning a watermarked image. For digital video, the corresponding concept is a Camcorder copy, where a video displayed on a screen is (digitally) recorded using a video camera. As most commercial video streaming systems (VOD, IPTV) and offline distribution (Blu-ray, HDDs for cinemas) are strongly protected by means of DRM, filming a display is actually a relevant use case and a requirement for robust video watermarking systems to survive. We therefore present a tool to simulate content re-acquisition with a Camcorder. Our goal is to support watermark development by enabling automated test cases for such Camcorder copy attacks, as well as to provide a benchmark for robust video watermarking. Manually creating Camcorder copies is a cumbersome process, and even more problematic, it is hardly reproducible with the same setup. By re-sampling each video frame, we simulate the typical artifacts of a Camcorder copy: geometric modifications (aspect ratio changes, cropping, perspective and lens distortion), temporal modifications (unsynchronized frame rates and the resulting frame blending), sub-sampling (rescaling, filtering, Bayer color array filter), and histogram changes (AGC, AWB). We also support simulating camera movement (e.g., a hand-held camera) and background insertion.
Dooseop Choi - One of the best experts on this subject based on the ideXlab platform.
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Fast communication: A blind MPEG-2 video watermarking robust to Camcorder recording
Signal Processing, 2010Co-Authors: Dooseop Choi, Hyuk Choi, Tae Jeong KimAbstract:Based on the observation that low-frequency DCT coefficients of an image are less affected by geometric processings, we propose a new blind MPEG-2 video watermarking algorithm robust to Camcorder recording. The mean of the low-frequency DCT coefficients of the video is temporally modulated according to the information bits. To avoid watermark's drift into other frames, we embed watermarks only in the B-frames of MPEG-2 videos, which also allows minimal partial decoding and achieves efficiency. Experimental results show that the proposed scheme achieves high video quality and robustness to Camcorder recording and other attacks.
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digital video watermarking based on histogram and temporal modulation and robust to Camcorder recording
International Symposium on Signal Processing and Information Technology, 2008Co-Authors: Hoseok Do, Dooseop Choi, Hyuk Jin ChoiAbstract:This paper presents a blind digital video watermarking scheme, which is especially robust to Camcorder recording attacks and also to a variety of common video processing and geometric distortions. Using the fact that nearby frames of a video sequence are quite similar, the method embeds the watermark by temporal modulation of the frames. The watermark pattern used in modulation is generated based on the pixel-value histogram, which makes extraction free from geometric synchronization. To make it imperceptible, the watermark is adjusted according roughly to the Human Visual System. The experimental results demonstrate the robustness of the proposed method to Camcorder recording attacks also involving geometric distortions and other video processing attacks such as MPEG and other compressions.
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Digital Video Watermarking Based on Histogram and Temporal Modulation and Robust to Camcorder Recording
2008 IEEE International Symposium on Signal Processing and Information Technology, 2008Co-Authors: Dooseop Choi, Hyuk Choi, Tae Jeong KimAbstract:This paper presents a blind digital video watermarking scheme, which is especially robust to Camcorder recording attacks and also to a variety of common video processing and geometric distortions. Using the fact that nearby frames of a video sequence are quite similar, the method embeds the watermark by temporal modulation of the frames. The watermark pattern used in modulation is generated based on the pixel-value histogram, which makes extraction free from geometric synchronization. To make it imperceptible, the watermark is adjusted according roughly to the Human Visual System. The experimental results demonstrate the robustness of the proposed method to Camcorder recording attacks also involving geometric distortions and other video processing attacks such as MPEG and other compressions.
Jan Lukas - One of the best experts on this subject based on the ideXlab platform.
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source digital Camcorder identification using sensor photo response non uniformity
Conference on Security Steganography and Watermarking of Multimedia Contents, 2007Co-Authors: Mo Chen, Jessica Fridrich, Miroslav Goljan, Jan LukasAbstract:Photo-response non-uniformity (PRNU) of digital sensors was recently proposed [1] as a unique identification fingerprint for digital cameras. The PRNU extracted from a specific image can be used to link it to the digital camera that took the image. Because digital Camcorders use the same imaging sensors, in this paper, we extend this technique for identification of digital Camcorders from video clips. We also investigate the problem of determining whether two video clips came from the same Camcorder and the problem of whether two differently transcoded versions of one movie came from the same Camcorder. The identification technique is a joint estimation and detection procedure consisting of two steps: (1) estimation of PRNUs from video clips using the Maximum Likelihood Estimator and (2) detecting the presence of PRNU using normalized cross-correlation. We anticipate this technology to be an essential tool for fighting piracy of motion pictures. Experimental results demonstrate the reliability and generality of our approach.
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Security, Steganography, and Watermarking of Multimedia Contents - Source digital Camcorder identification using sensor photo response non-uniformity
Security Steganography and Watermarking of Multimedia Contents IX, 2007Co-Authors: Mo Chen, Jessica Fridrich, Miroslav Goljan, Jan LukasAbstract:Photo-response non-uniformity (PRNU) of digital sensors was recently proposed [1] as a unique identification fingerprint for digital cameras. The PRNU extracted from a specific image can be used to link it to the digital camera that took the image. Because digital Camcorders use the same imaging sensors, in this paper, we extend this technique for identification of digital Camcorders from video clips. We also investigate the problem of determining whether two video clips came from the same Camcorder and the problem of whether two differently transcoded versions of one movie came from the same Camcorder. The identification technique is a joint estimation and detection procedure consisting of two steps: (1) estimation of PRNUs from video clips using the Maximum Likelihood Estimator and (2) detecting the presence of PRNU using normalized cross-correlation. We anticipate this technology to be an essential tool for fighting piracy of motion pictures. Experimental results demonstrate the reliability and generality of our approach.
Xiaolin Wu - One of the best experts on this subject based on the ideXlab platform.
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Defeating Camcorder Piracy by Temporal Psychovisual Modulation
Journal of Display Technology, 2014Co-Authors: Guangtao Zhai, Xiaolin WuAbstract:We present a new video projection technique to defeat Camcorder piracy in movie theaters using the newly emerged display paradigm of temporal psychovisual modulation. The technique exploits the difference in image formation mechanisms between human eyes and digital cameras: in the human visual system, images are formed via continuous integration of the light field, whereas digital video acquisition is based on discrete sampling of light sensors. A movie frame is decomposed into multiple so-called shale frames such that, when these shale frames are displayed at a frame rate higher than 60 Hz, the human viewers will experience normal movie presentation without any noticeable artifacts, but the video frames captured by Camcorders will contain severe, highly objectionable artifacts, depriving the pirated video contents of any commercial values.
