This work presents a parallel context-modeling coding architecture and a matching arithmetic coder (MQ coder) for the embedded block coding (EBCOT) unit of the JPEG2000 encoder. The Tier-1 of the EBCOT consumes most o...
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This work presents a parallel context-modeling coding architecture and a matching arithmetic coder (MQ coder) for the embedded block coding (EBCOT) unit of the JPEG2000 encoder. The Tier-1 of the EBCOT consumes most of the time in a JPEG2000 encoding system. The proposed parallel architecture can increase the throughput rate of the context-modeling. To match the high throughput rate of the parallel context-modeling architecture, an efficient pipelined architecture for context-based adaptive arithmetic encoder is proposed. This encoder of JPEG2000 can work at 185MHz to encode one symbol each cycle. To compare to the conventional context-modeling architecture the presented parallel architecture can improve the throughput rate up to 25%. Because of the high throughput rate of the parallel context-modeling architecture, the concept of multi-rate processing for low power design can be applied.
We propose a practical approach to JPEG image de-coding, utilizing a local implicit neural representation with continuous cosine formulation. The JPEG algorithm sig-nificantly quantizes discrete cosine transform (DCT)...
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ISBN:
(数字)9798350353006
ISBN:
(纸本)9798350353013
We propose a practical approach to JPEG image de-coding, utilizing a local implicit neural representation with continuous cosine formulation. The JPEG algorithm sig-nificantly quantizes discrete cosine transform (DCT) spec-tra to achieve a high compression rate, inevitably resulting in quality degradation while encoding an image. We have designed a continuous cosine spectrum estimator to address the quality degradation issue that restores the distorted spectrum. By leveraging local DCT formulations, our network has the privilege to exploit dequantization and upsampling simultaneously. Our proposed model enables decoding compressed images directly across different quality factors using a single pre-trained model without relying on a conventional JPEG decoder. As a result, our proposed network achieves state-of-the-art performance in flexible color image JPEG artifact removal tasks. Our source code is available at https://***/WooKyoungHan/Jdec.
A method for browsing large compressed images over the Internet is presented. Images are compressed using a very recent coded file format, referred to as JPEG XR, designed primarily for storage of continuous-tone phot...
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A method for browsing large compressed images over the Internet is presented. Images are compressed using a very recent coded file format, referred to as JPEG XR, designed primarily for storage of continuous-tone photographic images and currently at the beginning of the ISO/IEC standardization process. In the proposed method, region of interest specified by the user are progressively downloaded and displayed with an approach aiming to minimize the transferred information between the request and the image presentation. Experimental analysis show that the proposed method is an effective way for browsing large JPEG XR coded images.
We propose an adaptive wavelet transform that results in fewer large detail coefficients while preserving image contours in the approximation subband. The transform is constructed with a three-step nonlinear lifting s...
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We propose an adaptive wavelet transform that results in fewer large detail coefficients while preserving image contours in the approximation subband. The transform is constructed with a three-step nonlinear lifting scheme: a fixed prediction followed by a space-varying update and a non-additive prediction. The interest of the proposed scheme is demonstrated for nearly lossless compression.
A compression method is presented which combines the distinct advantage of being fixed length with the visual picture quality of transform-based coding methods. This method compresses the Karhunen-Loeve transform coef...
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A compression method is presented which combines the distinct advantage of being fixed length with the visual picture quality of transform-based coding methods. This method compresses the Karhunen-Loeve transform coefficients of 8/spl times/8 pixel blocks of the picture and attains a compression ratio of 15.37:1 for color images. Compared to the absolute moment block truncation coding, the other known fixed length compression method, our method improves the compression ratio by 68% and significantly improves the visual quality of the reconstructed picture.
This paper presents an HDTV video decoder core that is is able to decode MPEG-2, MPEG-4 AVC and VC-1 formats and is fully compatible with the Blu-ray Disc standard. A novel re-configurable architecture is adopted to a...
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This paper presents an HDTV video decoder core that is is able to decode MPEG-2, MPEG-4 AVC and VC-1 formats and is fully compatible with the Blu-ray Disc standard. A novel re-configurable architecture is adopted to achieve reduced hardware, and a data compression method suitable for all video decoding standards is applied to reduce memory data usage and access bandwidth. The circuit volume of the core is 1.5 Mgates with 90 nm CMOS technology and operation clock frequency is 162 MHz for 1080 i at 30 fr/s.
The authors consider the application of wavelet transform coding to SAR raw data compression at low bit rates. The performance of the method is evaluated by comparing some quality parameters measured before and after ...
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The authors consider the application of wavelet transform coding to SAR raw data compression at low bit rates. The performance of the method is evaluated by comparing some quality parameters measured before and after the SAR image formation with those achieved when using block adaptive quantization.
With the rapid spread of image and video processing applications and the further development of multimedia technologies, compression standards become more and more important every day. This study was conducted to inve...
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With the rapid spread of image and video processing applications and the further development of multimedia technologies, compression standards become more and more important every day. This study was conducted to investigate the role of compression standards in image processing. Digital watermarking algorithm for securing multimedia application is considered one of the most important applications heavily rely on compression standards. It was selected to perform our experimental study by employing wavelet and JPEG compression standards. An analysis of the experiment results indicated that the wavelet outperform JPEG compression standard and applications implemented wavelet have better performance than those implemented JPEG.
A source coding scheme for high-quality audio signals based on adaptive transform coding is presented. Using the well known ATC algorithm of R. Zelinski and P. Noll (1977) as a starting point, the authors have develop...
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A source coding scheme for high-quality audio signals based on adaptive transform coding is presented. Using the well known ATC algorithm of R. Zelinski and P. Noll (1977) as a starting point, the authors have developed an algorithm that features psychoacoustic weighting and a joint bit allocation to stereo channels. The real-time implementation uses a four-node processor network, each node consisting of a T800 transputer and a DSP32 signal processor. Both the codec optimization and the evaluation of subjective quality are facilitated by the fact that many of the codec parameters can be changed online.< >
Several criteria can be used to assess the criticality of registers or variables at compile time and to guide software optimization with respect to robustness constraints. On the basis of such criteria, we analyze in ...
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Several criteria can be used to assess the criticality of registers or variables at compile time and to guide software optimization with respect to robustness constraints. On the basis of such criteria, we analyze in detail the impact of compilation optimizations on the system dependability. We show that optimizations enabled by default lead to criticality increase. However, selectively picking optimizations may increase the robustness of a system even if the consequences of a given optimization option may vary from a program to another.
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