In this paper we investigate the use of a fully rate scalable wavelet codec known as SAMCoW (Scalable Adaptive Motion Compensated Wavelet) for use in robust video streaming. We develop a theory based on the notion of ...
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ISBN:
(纸本)0819439886
In this paper we investigate the use of a fully rate scalable wavelet codec known as SAMCoW (Scalable Adaptive Motion Compensated Wavelet) for use in robust video streaming. We develop a theory based on the notion of additive temporal distortion to predict the performance of the bit stream under error conditions. Due to the regular nature of SAMCoW a closed-form solution is found and compared experimentally to a SAMCoW stream in a simulated channel.
In this paper, we propose a novel joint image compression and encryption technique where an annoying image can still be recovered even without the encryption key. Our work is based on JPEG standard. By embedding encry...
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ISBN:
(纸本)9781467373142
In this paper, we propose a novel joint image compression and encryption technique where an annoying image can still be recovered even without the encryption key. Our work is based on JPEG standard. By embedding encryption algorithm at the transformation stage, we realize image encryption and compression together with controllable image quality. Instead of using the 8x8 discrete cosine transform (DCT) alone for transformation, we develop new orthogonal transforms by introducing sign-flips into the butterflies of DCT's flow-graph structure, and then employ them alternatively in JPEG's transformation stage according to a secret key. By carefully selecting the butterflies for sign-flipping, we can control the visual quality of the encrypted images. Finally, a detailed security analysis of our proposed encryption algorithm is presented to show its resistance to various attacks, such as cryptographic attack, replacement attack and statistical model-based attack.
To consider the quality of service for stereoscopic image through the network, it: is necessary to develop a quality evaluation model for coded stereoscopic image. We propose a quality evaluation model of the coded st...
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ISBN:
(纸本)0819437034
To consider the quality of service for stereoscopic image through the network, it: is necessary to develop a quality evaluation model for coded stereoscopic image. We propose a quality evaluation model of the coded stereoscopic color image. This evaluation model considers not only the distortions of the edge region and smooth region but also the texture features of the left image. In addition, this model also takes into account the disparity information between the left and right images. Instead of the disparity compensated coded image, we employ the JPEG coded image for the subjective assessment test. As the results, the evaluation model is useful for coded stereoscopic image.
This paper deals with a class of morphological operators called connected operators. These operators interact with the signal by merging flat zones. As a result, they do not create any new contours and are very attrac...
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ISBN:
(纸本)0819424358
This paper deals with a class of morphological operators called connected operators. These operators interact with the signal by merging flat zones. As a result, they do not create any new contours and are very attractive for filtering tasks where the contours information has to be preserved. This paper focuses on a class of operators dealing with motion information. They remove from the original sequence the components that do not undergo a specific motion. They have a large number of applications including image sequence analysis with motion multiresolution decomposition and motion estimation.
In this paper, we propose a method that can automatically translate regular human faces to Yesilcam artists. Throughout the paper, two important contributions are presented. First, since a classifier based approach is...
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ISBN:
(纸本)9781538615010
In this paper, we propose a method that can automatically translate regular human faces to Yesilcam artists. Throughout the paper, two important contributions are presented. First, since a classifier based approach is used, the proposed method automatically selects the most similar artist and makes the face translation. Second, so as to obtain the latent information about faces, a pre-trained model is utilized at the encoder part. Experiments show that visual results which are perceptually promising, Yesilcam artist-like yet preserving facial features of a person, can be synthesized.
image transformation refers to transforming images from a source image space to a target image space. Contemporary image transformation methods achieve this by learning coupled dictionaries from a set of paired images...
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ISBN:
(纸本)9781479961399
image transformation refers to transforming images from a source image space to a target image space. Contemporary image transformation methods achieve this by learning coupled dictionaries from a set of paired images. However, in practical use, such paired training images are not easy to get especially when the target image style is not fixed. Thus in most cases, the reference is limited. In this paper, we propose a sparse representation based framework of transforming images with limited reference, which can be used for the typical image transformation application, photo-sketch synthesis. In the learning stage, the edge features are utilized to map patches between different style images, thus building the coupled database for dictionary learning. In the reconstruction stage, sparse representation can well preserve the basic structure of image contents. In addition, a texture synthesis strategy is introduced to enhance target-like textures in the output image. Experimental results show that the performance of our method is comparable to state-of-the-art methods even with limited reference, which is very efficient and less restrictive for practical use.
The code generated by fractal coding of a digital image provides a resolution-independent representation of the image as this code can be decoded to generate a digital image at any resolution. When the image is decode...
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ISBN:
(纸本)0819424358
The code generated by fractal coding of a digital image provides a resolution-independent representation of the image as this code can be decoded to generate a digital image at any resolution. When the image is decoded at a size larger than the original encoded image, image details beyond the resolution of the original image are predicted by assuming local self-similarity in image at different scales. In this paper, we (1) present a formulation of how decoding may be done at a higher resolution, (2) evaluate the accuracy of the predicted details using a frequency analysis of fractally enlarged test images, and (3) propose a method for fractal resolution enhancement without the low-frequency loss of information due to fractal coding.
A variable bit-rate HDTV coding algorithm based on motion-adaptive DCT is investigated for ATM environments in B-ISDN. Adaptive 2-layered coding, an ATM cell matrix for error correction, and a block interleave for err...
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ISBN:
(纸本)0819407429
A variable bit-rate HDTV coding algorithm based on motion-adaptive DCT is investigated for ATM environments in B-ISDN. Adaptive 2-layered coding, an ATM cell matrix for error correction, and a block interleave for error concealment are proposed to keep picture quality high by compensating for ATM cell loss. A new VLC and a congestion control scheme that restricts peak-rate and average-rate are also proposed for traffic control. The proposed algorithm is shown to reduce the coding bit-rate for HDTV conference applications in ATM environments to 10 - 30 Mb/s.
An image retargeting method is presented in this paper, which uses multiple operators to improve the performance. In the method, cropping is adopted first in order to remove non-important content to the desired aspect...
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ISBN:
(纸本)9781467373142
An image retargeting method is presented in this paper, which uses multiple operators to improve the performance. In the method, cropping is adopted first in order to remove non-important content to the desired aspect ratio while keeping significant content intact. If the desired aspect ratio cannot be met by cropping, an aspect ratio adjusting method is then adopted to fit the image to the desired aspect ratio. Uniform scaling is used in the last stage to adjust the image to the desired size. Since aspect ratio needs no change, the scaling can retain all the information without causing any distortion. Since different operators are applied in different stages, their benefits are fully utilized and drawbacks can be avoided. Experimental result shows that this approach can improve the retargeting performance at a low computation cost.
In most IFS based image coding schemes, the domain blocks codebook searched is independent from the input image, identical for all range blocks of the same size, and non optimized. In order to get a good match between...
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ISBN:
(纸本)0819421030
In most IFS based image coding schemes, the domain blocks codebook searched is independent from the input image, identical for all range blocks of the same size, and non optimized. In order to get a good match between range and domain blocks, a huge codebook is used, which is both inefficient in terms of computational complexity and output bit rate. We propose to design an optimal reduced codebook for the whole image thanks to a geometrical analysis of the basic scheme. We then compare this method with a 'local' codebook method, which leads us to some conclusions about the differences between IFS and vectorial quantization (VQ) based coding schemes.
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