In this paper, a digital image watermarking technique based on discrete wavelet transform (DWT) will be proposed. This scheme is designed utilizing principles deriving from the human visual system, JPEG standard compr...
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In this paper, a digital image watermarking technique based on discrete wavelet transform (DWT) will be proposed. This scheme is designed utilizing principles deriving from the human visual system, JPEG standard compression algorithm and DWT decomposition. It is optimized special for against JPEG compression. The watermark signal as a binary sequence is embedded to the diagonal higher frequency band at 2-D level DWT decomposition of Y channel in YUV color model. The experiment shows that the proposed scheme has strong robust to against JPEG compression, some popular filtering and geometrical attacks.
An anti-dictionary is in particular useful for data compression, and it consists of minimal forbidden words for a given string. We derive the average length M n of minimal forbidden words in strings of length n under...
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An anti-dictionary is in particular useful for data compression, and it consists of minimal forbidden words for a given string. We derive the average length M n of minimal forbidden words in strings of length n under a stationary ergodic source with entropy H which takes values on a finite alphabet. For the string length n, we prove, log n/M n = H, in probability, as n rarr infin. We use the Wyner-Ziv result, with respect to connection between entropy and recurrence-time for ergodic processes, to prove the theorem. Its validity is shown by simulation results on a memoryless binary information source.
A view synthesis-oriented depth map coding algorithm is proposed in this paper. Depth map is classified into inner motion regions, background subtracted with edges and edge regions by using edge detection of current d...
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A view synthesis-oriented depth map coding algorithm is proposed in this paper. Depth map is classified into inner motion regions, background subtracted with edges and edge regions by using edge detection of current depth map and the frame difference between corresponding color images. Then macroblocks in different regions are encoded with different RDO schemes so as to speed up the encoding process while keep the quality of reconstructed depth map. Experimental results show that the proposed method not only improves the encoding speed significantly, but also saves bitrate of depth map sequence while maintaining high quality of synthesized virtual view images.
This paper proposes a novel frame memory compression algorithm, called Pixel-Parallel SPIHT (PPS) that processes image data in parallel to increase the encoding throughput. The throughput of a PPS coder is an average ...
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ISBN:
(纸本)9781424449408
This paper proposes a novel frame memory compression algorithm, called Pixel-Parallel SPIHT (PPS) that processes image data in parallel to increase the encoding throughput. The throughput of a PPS coder is an average of 4.48 bits per cycle which is 48.7 times larger than that of No List SPIHT.
With the development of space telemetry technology, it has brought forward higher requests for large capacity memory of hard recovered solid-state recorders. Therefore, data compression becomes more important. The com...
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With the development of space telemetry technology, it has brought forward higher requests for large capacity memory of hard recovered solid-state recorders. Therefore, data compression becomes more important. The compression feasibility and potentiality of telemetry data are examined by analyzing the statistical characteristics of actual telemetry data recovered from the recorder. Aiming at the disadvantages of present data format in data compression for multi-channel telemetry data acquisition systems, we introduce data packet structure and a real-time compression algorithm for low complex hardware design put forward accordingly. The principles and implementation of data package compression are described. Simulation results show that this technology can meet the requirements of multi-channel real-time data compression with high compression ratio and fast compression speed, which possesses great application values.
Many compression algorithms consist of quantizing the coefficients of an image in a linear basis. This introduces compression noise that often look like ringing. Recently some authors proposed variational methods to r...
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Many compression algorithms consist of quantizing the coefficients of an image in a linear basis. This introduces compression noise that often look like ringing. Recently some authors proposed variational methods to reduce those artifacts. They consists of minimizing a regularizing functional in the set of antecedents of the compressed image. In this paper we propose a fast algorithm to solve that problem. Our experiments lead us to the conclusion that these algorithms effectively reduce oscillations but also reduce contrasts locally. To handle that problem, we propose a fast contrast enhancement procedure. Experiments on a large dataset suggest that this procedure effectively improves the image quality at low bitrates.
We present a framework for considering the problem of compressing large collections of similar sequences. In this framework, an unknown individual sequence is modified several times independently to obtain the collect...
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ISBN:
(纸本)9781424422562
We present a framework for considering the problem of compressing large collections of similar sequences. In this framework, an unknown individual sequence is modified several times independently to obtain the collection of sequences to be compressed. For certain collections generated by context-dependent bit flips of the individual sequencepsilas bits, and for those generated by simple edit operations on the individual sequence, we derive universal compression algorithms that compress the collection of sequences almost as well as an optimal compressor that has knowledge of the underlying individual sequence and the modifying processes.
The maximum compression, efficient transmission and fast rendering of geometric models is a complex problem for many reasons, thereby gaining a lot of attention from several areas, like compression and rendering of ge...
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ISBN:
(纸本)9788086943169
The maximum compression, efficient transmission and fast rendering of geometric models is a complex problem for many reasons, thereby gaining a lot of attention from several areas, like compression and rendering of geometric models. Normally, the stripification algorithms are used to speed up the rendering of geometric models because they reduce the number of vertices sent to the graphics pipeline by exploiting the fact that adjacent triangles share an edge. In this paper, we present a new compression algorithm based on stripification of geometric models that enable us a progressive visualization of the models during its transmission. It occurs because our algorithm encodes and decodes the geometry and the connectivity of the model in an interwoven fashion. The main purpose is the storage of object files as strips files in server computer, which enables faster transmission and display of the models at client side. In fact, our compression algorithm achieves compression ratios above 40:1 over ASCII encoded formats and the triangle strips improve rendering performance.
Image compression reduces time and cost in image storage without significant reduction of the image quality. This paper puts forward a wavelet-based predictive image coding algorithm, which has a higher coding rate th...
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ISBN:
(纸本)9780769534893
Image compression reduces time and cost in image storage without significant reduction of the image quality. This paper puts forward a wavelet-based predictive image coding algorithm, which has a higher coding rate than traditional coding algorithm. Based on the algorithm above, this article adopts the selective image compression technique to compress facial images. This algorithm attains a compression ratio from decade to several decades and settles the transmission and storage problem preferably.
We present a formal method to determine whether there exist living creatures in a given computational environment. Our proposal is based on studying the evolution of the entropy of the Studied system. In particular. W...
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ISBN:
(纸本)9783540876991
We present a formal method to determine whether there exist living creatures in a given computational environment. Our proposal is based on studying the evolution of the entropy of the Studied system. In particular. We check whether there exist entities decreasing the entropy in sonic parts, while increasing it in the rest of the world, which fits into the well-known maximum entropy production principle. The entropy of a computational environment is measured in terms of its compression rate with respect to some compression strategy. Some life-related notions Such as biodiversity are quantified as Well. These ideas are presented by means of formal definitions. A toy example where a simple living structure is identified in a video stream is presented. and some results are reported.
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