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With the constant evolution of video technology and the deployment of new video services, content providers and broadcasters always face the challenge of delivering an adequate video quality which meets end-users expectations. The development of reliable quality testing and quality monitoring tools that can be used by broadcasters ultimately requires reliable objective video quality metrics. In turn,...
In this paper, we propose a method for detecting resized JPEG images. We defined 8 × 8 periodic blocks as JPEG blocks. JPEG block boundaries are detected by applying 8 × 8 block discrete cosine transform (DCT) to all the pixels of the input image and analyzing the high frequency coefficients in them. In order to quantitatively analyze the degree of forgery, we have developed two approaches such as...
For image and video compression standards, one image is divided into a serial of non-overlapped blocks. Detecting edge existence and analyzing the edge direction in a block level is useful in the applications, such as perceptually improved coding, MB encoding mode decision, blocking artifacts reduction, content-based retrieval, senses changing detection, etc. This paper proposes a novel Fast Block...
A wide variety of real world systems require reliable personal recognition schemes to either confirm or determine the identity of an individual requesting their services. Biometric recognition scheme refers to the automatic recognition/identification of individuals based on their physiological and/or behavioral characteristics. We have proposed a Vein Based Personal Identification System (VBPIS),...
In this paper, we propose novel algorithmic models based on feature transformation in cross-modal subspace and their multimodal fusion for different types of residue features extracted from several intra-frame and inter frame pixel sub-blocks in video sequences for detecting digital video tampering or forgery. An evaluation of proposed residue features - the noise residue features and the quantization...
Though the variety of desktop real time stereo vision systems has grown considerably in the past several years, few make any verifiable claims about the accuracy of the algorithms used to construct 3D data or describe how the data generated by such systems, which is large in size, can be effectively distributed. In this paper, we describe a system that creates an accurate (on the order of a centimeter),...
The Mixed Raster Content (MRC) standard (ITU-T T.44) specifies a framework for document compression which can dramatically improve the compression/quality tradeoff as compared to traditional lossy image compression algorithms. The key to MRC's performance is the separation of the document into foreground and background layers, represented as a binary mask. In this paper, we propose a novel multiscale...
We classify the visibility of TS (Transport Stream) packet losses for SDTV and HDTV MPEG-2 compressed video streams. TS packet losses can cause various temporal and spatial losses. The visual effect of a TS packet loss depends on many factors, in particular whether the loss causes a whole frame loss or partial frame loss. We develop models for predicting loss visibility for both SDTV and HDTV resolutions...
H.264/AVC is one of the state of the art in video compressing standards. It has advantages of low bit-rate and high image quality. However, the complexity of H.264/AVC encoder limits applications in the real time video communication. In this study, a fast intra prediction with Haar transform algorithm (FIPHTA) is proposed to simplify the complexity of luma intra prediction. For each luma macroblock...
This paper proposes a method used to improve the retrieval performance of the digital watermarking based on the modification of image pixels. By embedding the watermark in the chrominance channel and using the mean filter with 3??3 window size in the watermark extraction process, the accuracy of the extracted watermark can be improved. Sets of experiment are carried out to verify our concept. The...
Triplet-stereo imagery from the PRISM instrument on the ALOS satellite has been processed to a digital elevation model (DEM) for use in soil prediction models. A number of artefacts in the ALOS-PRISM imagery appear to limit the quality of the stereo imagery, and thus the derived DEM. Even/odd column striping has been reduced in its effect by a change in processing in early 2007, but some residual...
In information security, steganalysis has been an important topic since evidences first indicated steganography has been used for covert communication. Among all digital files, numerous devices generate JPEG images due to the capability of compression and compatibility. A large number of JPEG steganography methods are also provided online for free usage. This has spawned significant research in the...
Video quality evaluation is an important component in improving the user experience in many multimedia applications. Therefore, there is significant interest in generating objective video quality metrics that can accurately estimate the perceived quality of image sequences. Many existing video quality metrics, however, do not explicitly account for temporal artifacts that occur in video compression...
In this paper, we present a novel fast video search algorithm for large video database. This algorithm is based on the adjacent pixel intensity difference quantization (APIDQ) algorithm, which had been reliably applied to human face recognition previously. An APIDQ histogram is utilized as the feature vector of the frame image. Combined with active search, a temporal pruning algorithm, fast and robust...
The integral image is an image containing accumulated sums of pixel values taken from an input image. It is an important concept for multi-scale image processing algorithms, for it provides a very economic way to compute the sum of pixel values in any rectangular input image region. Unfortunately, the integral image requires a large binary word length to represent the accumulated sums. This is an...
In sports videos, text information provides valuable game information such as scores, players, and so on. This text information plays an important role for sports video understanding, summarization, and retrieval. These texts which can be used for video highlight or content search are called key captions. In this paper, we provide a robust detection method of key captions in sports videos. We also...
High efficiency of multibeam sonar system (MBS) hardware due to operational requirements (i.e. high frequency, high ping rate and high resolution of collected data) results in very large volumes of datasets stored on local hard drives of operatorpsilas station. In this context, the process of archiving of such warehouse of data collected in previous surveys becomes crucial problem. The paper investigates...
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