Providing high bit rate real-time video services has been a major driving factor in the advancement of high speed networking technology such as ATM based BISDN. In this paper, we describe MPEG2Tool, an X-window-based ...
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ISBN:
(纸本)0819420425
Providing high bit rate real-time video services has been a major driving factor in the advancement of high speed networking technology such as ATM based BISDN. In this paper, we describe MPEG2Tool, an X-window-based software implementation of the MPEG-2 videocompression algorithm with many additional useful functions. The ultimate goal of designing this toolkit was to facilitate the study of MPEG video transmission over ATM-based networks. The toolkit consists of four major modules, which appear as four push-buttons in the main Motif menu: (1) encoding, (2) statistical analysis, (3) transmission simulation, and (4) decoding.
Recent years have seen tremendous growth and advancement in the field of super-resolution algorithms for both images and videos. Such algorithms are mainly based on deep learning technologies and are primarily used fo...
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Embedded captions in TV programs such as news broadcasts, documentaries and coverage of sports events provide important information on the underlying events. In digitalvideo libraries, such captions represent a highl...
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ISBN:
(纸本)0819420425
Embedded captions in TV programs such as news broadcasts, documentaries and coverage of sports events provide important information on the underlying events. In digitalvideo libraries, such captions represent a highly condensed form of key information on the contents of the video. In this paper we propose a scheme to automatically detect the presence of captions embedded in video frames. The proposed method operates on reduced image sequences which are efficiently reconstructed from compressed MPEG video and thus does not require full frame decompression. The detection, extraction and analysis of embedded captions help to capture the highlights of visual contents in video documents for better organization of video, to present succinctly the important messages embedded in the images, and to facilitate browsing, searching and retrieval of relevant clips.
compression has enabled years of exponential growth in global video consumption, providing video everywhere, with few perceptible artifacts. Automated video Quality Assessment (VQA) is an enabler of compression. We pr...
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ISBN:
(纸本)9781628417654
compression has enabled years of exponential growth in global video consumption, providing video everywhere, with few perceptible artifacts. Automated video Quality Assessment (VQA) is an enabler of compression. We present data showing video contrast affects on artifact visibility. Based on our data, we propose a contrast-gaincontrol VQA algorithm, with target spatiotemporal property weighting, and using our data to tune existing VQA algorithms for improved artifact threshold predictions. This paper provides much needed data on natural video mask contrast and artifact visibility, and provides important insights for how VQA algorithms can be improved to better predict video quality in the high-quality regime.
Traditional objective measurements are of limited effectiveness in predicting the quality of compressed images. Subjective assessment is the most reliable method of evaluation of compression systems performance now. B...
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ISBN:
(纸本)0819423564
Traditional objective measurements are of limited effectiveness in predicting the quality of compressed images. Subjective assessment is the most reliable method of evaluation of compression systems performance now. But subjective assessment is time consuming. That is why it is important to simplify the procedure of subjective measurement. To achieve it one may use the method of paired comparisons. This paper describes applications of the method of paired comparisons in the field of assessment of concatenated compression systems.
Due to the increasing number of new services and devices that allow the creation, distribution and consumption of video content, the amount of video information being transmitted all over the world is constantly growi...
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Due to the increasing number of new services and devices that allow the creation, distribution and consumption of video content, the amount of video information being transmitted all over the world is constantly growing. videocompression technology is essential to cope with the ever increasing volume of digitalvideo data being distributed in today's networks, as more e cient videocompression techniques allow support for higher volumes of video data under the same memory/bandwidth constraints. This is especially relevant with the introduction of new and more immersive video formats associated with signi cantly higher amounts of data. In this thesis, novel techniques for improving the e ciency of current and future video coding technologies are investigated. Several aspects that in uence the way conventional video coding methods work are considered. In particular, the properties and limitations of the Human Visual System are exploited to tune the performance of video encoders towards better subjective quality. Additionally, it is shown how the visibility of speci c types of visual artefacts can be prevented during the video encoding process, in order to avoid subjective quality degradations in the compressed content. Techniques for higher videocompression e ciency are also explored, targeting to improve the compression capabilities of state-of-the-art video coding standards. Finally, the application of video coding technologies to practical use-cases is considered. Accurate estimation models are devised to control the encoding time and bit rate associated with compressed video signals, in order to meet speci c encoding time and transmission time restrictions.
videocompression was widely adopted for bandwidth saving reasons in Internet and in digital TV. Although advanced compression methodologies were exceedingly desirable for much higher compression ratios and much bette...
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ISBN:
(纸本)0819449628
videocompression was widely adopted for bandwidth saving reasons in Internet and in digital TV. Although advanced compression methodologies were exceedingly desirable for much higher compression ratios and much better quality of a streaming video, the standard compression methods remained nevertheless at the level of JPEG2000 for single frames of images using DCT & wavelets, and WEG using DCT and exhaustive pixel correlations for the optical flow compression for the video. However, with the recent advent of sophisticated sensory technologies for NASA space missions, both the frame rate and the resolution of video streams become soon beyond the traditional capability of those DCT based compression methods. The goal was to find fundamental units of video that could be applied to the ultra-high frame rates of video streams. In this paper a novel implementation of videocompression was based on the singularity maps in both space and time for the first time.
To deal with the temporal redundancy of an input video sequence H.261 Standard specifics to use displaced frame differences with reference frames and, optionally, motion compensation technique. Usually, encoding proce...
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ISBN:
(纸本)0819423564
To deal with the temporal redundancy of an input video sequence H.261 Standard specifics to use displaced frame differences with reference frames and, optionally, motion compensation technique. Usually, encoding process is performed in a loop comprising reconstruction of a reference frame in spatial domain along with the computation of a difference between a successive input video frame and its reference, followed by DCT compression of that displaced frame difference. In this paper we show that the reference frames can be reconstructed in the transform domain instead, having no impact on the computational accuracy and output bitstream. In this way, we represent all reference frames in the transform domain in a form of dequantized DCT coefficients, so the next inter-frame is a difference between the next DCT-transformed input picture and the current reference frame. This inter-frame is then quantized and entropy encoded on a regular basis. The output bitstream remains to be H.261-compliant, while the compression ratio as well as quality of the decompressed video are the same as in conventional implementation. We also present the performance results for the software codec running on Pentium PC.
The paper is concerned with theoretical and practical problems related to real time acquisition and storage of standard PAL/SECAM images and also with developing fast software algorithms for digital image processing. ...
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ISBN:
(纸本)0819412236
The paper is concerned with theoretical and practical problems related to real time acquisition and storage of standard PAL/SECAM images and also with developing fast software algorithms for digital image processing. A first section of the paper comprises the description of the block diagram of the PC plug-in conversion unit and a second one refers to practical image data compression and basic image processing algorithms.
The development of video quality metrics and perceptual video quality metrics has been a well established pursuit for more than 25 years. The body of work has been seen to be most relevant for improving the performanc...
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ISBN:
(数字)9781510620766
ISBN:
(纸本)9781510620766
The development of video quality metrics and perceptual video quality metrics has been a well established pursuit for more than 25 years. The body of work has been seen to be most relevant for improving the performance of visual compressionalgorithms. However, modeling the human perception of video with an algorithm of some sort is notoriously complicated. As a result the perceptual coding of video remains challenging and no standards have incorporated perceptual video quality metrics within their specification. In this paper we present the use of video metrics at the system level of a video processing pipeline. We show that it is possible to combine the artefact detection and correction process by posing the problem as a classification exercise. We also present the use of video metrics as part of a classical testing pipeline for software infrastructure, but here it is sensitive to the perceived quality in picture degradation.
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