This paper presents a new method, called Spatial Dynamic Motion Compensation (SDMC), which applies the concept of global motion to the coding of motion trajectory information for the purpose of side information reduct...
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ISBN:
(纸本)0819417661
This paper presents a new method, called Spatial Dynamic Motion Compensation (SDMC), which applies the concept of global motion to the coding of motion trajectory information for the purpose of side information reduction in digitalvideo signal compression. The experimental results of the SDMC algorithms presented in this paper have shown that the new method yields significant improvements in terms of bit rate reduction of motion information over the method used in MPEG-1, while maintaining a comparable reconstructed picture quality, when the video sequences possess significant global translational motion.
JPEG picture compression and related algorithms are not only used in still picture compression, but also to a growing degree for moving picture compression in telecommunication applications. Real-time JPEG compression...
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ISBN:
(纸本)0819417661
JPEG picture compression and related algorithms are not only used in still picture compression, but also to a growing degree for moving picture compression in telecommunication applications. Real-time JPEG compression and decompression are crucial in these scenarios. We present a method to significantly improve the performance of software based JPEG decompression. Key to these performance gains are adequate knowledge of the structure of the JPEG coded picture information and transfer of structural information between consecutive processing steps. Our implementation achieved an 80% performance increase decompressing typical JPEG video streams.
In this research, we propose a novel low bit rate videocompression scheme that consists of three major components: hybrid wavelet-JPEG compression, feature-preserving compression via multizone decomposition and windo...
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ISBN:
(纸本)0819417661
In this research, we propose a novel low bit rate videocompression scheme that consists of three major components: hybrid wavelet-JPEG compression, feature-preserving compression via multizone decomposition and window selection and tracking.
Fractal image compression is a promising new technology that may successfully provide a codec for PC-to-PC video communications. Unfortunately, the large amount of computation needed for the compression stage is a maj...
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ISBN:
(纸本)0819417661
Fractal image compression is a promising new technology that may successfully provide a codec for PC-to-PC video communications. Unfortunately, the large amount of computation needed for the compression stage is a major obstacle that needs to be overcome. This paper introduces the Fast Fractal Image compression algorithm, a new approach to breaking the `speed problem' that has plagued previous efforts. For still images, experiments show that at comparable quality levels the FFIC algorithm is 5 to 50 times faster than the current state of the art. Such an improvement brings real-time video applications within the reach of fractal mathematics.
This paper surveys the visual distortions introduced by a compression scheme into the reconstruction of a video sequence. Specifically, the paper will concentrate on systems utilizing motion compensation (MC), differe...
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ISBN:
(纸本)0819417661
This paper surveys the visual distortions introduced by a compression scheme into the reconstruction of a video sequence. Specifically, the paper will concentrate on systems utilizing motion compensation (MC), differential pulse code modulation (DPCM), and the discrete cosine transform (DCT). Such systems are exemplified by the CCITT H.261 and MPEG standards. In addition to the artifacts that have already been widely considered, such as `blocking' and `mosquito' effects, new classifications of artifacts will be presented. A concise characterization and demonstration of each artifact will be provided. This will include the specification of the distribution of the artifact within the reconstructed frames, and its correlation with the local spatial/temporal features within the sequence. Also noted will be the specific causes of the artifacts, with relation to the MC/DPCM/DCT components. Since the human visual system is, typically, the final judge of the quality of the reconstructed sequence, it is also important to note the level of severity of the artifacts that make the artifacts visually noticeable.
This paper presents the video processing techniques for indexing MPEG video sequences. Parameters encoded in P- and B-pictures are used to detect scene changes. In the MPEG format, P- and B-pictures consist of two typ...
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ISBN:
(纸本)0819417661
This paper presents the video processing techniques for indexing MPEG video sequences. Parameters encoded in P- and B-pictures are used to detect scene changes. In the MPEG format, P- and B-pictures consist of two types of information: difference matrix and motion vector(s) for every macroblock (MB). Different types of MBs indicate the relationship between the current picture and its reference picture(s). The proposed techniques take advantage of those parameters encoded in the MPEG video streams to detect some changes. Since motion information in the MPEG format is used, these novel techniques are reliable, accurate, and fast. Those techniques and algorithms are presented in detail and examples are provided.
We describe a technique for videocompression, based on a mosaic image representation obtained from all frames in a scene sequence, giving a panoramic view of the scene. We describe two types of mosaics, static and dy...
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ISBN:
(纸本)0819417661
We describe a technique for videocompression, based on a mosaic image representation obtained from all frames in a scene sequence, giving a panoramic view of the scene. We describe two types of mosaics, static and dynamic, which are suited for storage and transmission applications, respectively. In each case, the mosaic construction process aligns the images using a global parametric motion transformation, usually canceling the effect of camera motion on the dominant portion of the scene. The residual motions that are not compensated by the parametric motion are then analyzed for their significance and coded. The mosaic representation exploits large scale spatial and temporal correlations in image sequences. In many applications where there is significant camera motion (e.g., remote surveillance), it performs substantially better than traditional interframe compression methods, and offers the potential for very low bitrate transmission. In storage applications, such as digital libraries and video editing environments, it has the additional benefit of enabling direct access and retrieval of single frames at a time.
An effective video coding algorithm is described. It is based on a new quadtree block merging algorithm and wavelet decomposition of video signals using orthonormal and biorthogonal filter banks. With the merging algo...
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ISBN:
(纸本)0819417661
An effective video coding algorithm is described. It is based on a new quadtree block merging algorithm and wavelet decomposition of video signals using orthonormal and biorthogonal filter banks. With the merging algorithm the motion compensated predicted images are represented by a small set of rectangular regions in order to improve the coding efficiency and to minimize the border effects associated to the wavelet transform. A new solution to the problem of processing finite length signals by wavelet transforms, based on time-varying perfect reconstruction filter banks will be developed. Results of coding simulations using the merging algorithm with 8 X 8 and 16 X 16 blocks are presented. Also, subjects such as, choice of the optimal filter bank, boundary effects, optimal scalar quantization of the wavelet coefficients and prediction error filtering by wavelet decompositions will be discussed.
For MPEG video coding and recording applications, it is important to select quantization parameters at slice and macroblock levels to produce nearly constant quality image for a given bit count budget. A well designed...
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ISBN:
(纸本)0819417661
For MPEG video coding and recording applications, it is important to select quantization parameters at slice and macroblock levels to produce nearly constant quality image for a given bit count budget. A well designed rate control strategy can improve overall image quality for video transmission over a constant-bit-rate channel and fulfill editing requirement of video recording, where a certain number of new pictures are encoded to replace consecutive frames on the storage media using at most the same number of bits. In this paper, we developed a feedback method with a rate-quantization model, which can be adapted to changes in picture activities. The model is used for quantization parameter selection at the frame and slice level. Extra computations needed are modest. Experiments show the accuracy of the model and the effectiveness of the proposed rate control method. A new bit allocation algorithm is then proposed for MPEG video coding.
An algorithm is proposed for the detection of abrupt scene change and special editing effects such as dissolve in a compressed MPEG/MPEG-2 bitstream with minimal decoding of the bitstream. Scene changes are easily det...
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