检索结果-内蒙古大学图书馆

An FPGA implementation of a neural optimization of block truncation coding for image/video compression

MICROPROCESSORS AND MICROSYSTEMS 2007年第8期31卷 477-486页

作者： Saif, Sherif Abbas, Hazent M. Nassar, Salwa M. Wahdan, Abdelmonem A. Mentor Graph Corp Cairo 11341 Egypt Elect Res Inst Comp & Syst Dept Giza Egypt Ain Shams Univ Dept Comp & Syst Engn Cairo Egypt

This paper presents a Field Programmable Gate Array (FPGA) implementation for image/video compression using an improved block truncation coding (BTC) image compression technique. The improvement is achieved by employing a Hopfield neural network (HNN) to calculate a cost function upon which a block is classified as either a high- or a low-detail block. Accordingly, different blocks are coded with different bit rates and thus resulting in better compression ratios. The paper formulates the utilization of HNN within the BTC algorithm in such a way that a viable FPGA implementation is produced. The implementation exploits the inherent parallelism of the BTC/HNN algorithm to provide efficient algorithm-to-architecture mapping. The Xilinx VirtexE BTC implementation has shown to provide a processing speed of about 1.113 x 10(6) of pixels per second with a compression ratio which varies between 1.25 and 2 bits/pixel, according to the image nature. (C) 2006 Elsevier B.V. All rights reserved.

关键词： field programmable gate arrays block truncation coding Hopfield neural networks image/video compression

来源：评论

学校读者我要写书评

暂无评论

Hierarchical Method for Foreground Detection Using Codebook Model

引用

IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY 2011年第6期21卷 804-815页

作者： Guo, Jing-Ming Liu, Yun-Fu Hsia, Chih-Hsien Shih, Min-Hsiung Hsu, Chih-Sheng Natl Taiwan Univ Sci & Technol Taipei 10607 Taiwan

This paper presents a hierarchical scheme with block-based and pixel-based codebooks for foreground detection. The codebook is mainly used to compress information to achieve a high efficient processing speed. In the block-based stage, 12 intensity values are employed to represent a block. The algorithm extends the concept of the block truncation coding, and thus it can further improve the processing efficiency by enjoying its low complexity advantage. In detail, the block-based stage can remove most of the backgrounds without reducing the true positive rate, yet it has low precision. To overcome this problem, the pixel-based stage is adopted to enhance the precision, which also can reduce the false positive rate. Moreover, the short-term information is employed to improve background updating for adaptive environments. As documented in the experimental results, the proposed algorithm can provide superior performance to that of the former related approaches.

关键词： Background subtraction block truncation coding foreground detection shadow detection surveillance

来源：评论

学校读者我要写书评

暂无评论

Lapped transform-based codec for frame-memory reduction in super-quality LCD overdrive

引用

JOURNAL OF THE SOCIETY FOR INFORMATION DISPLAY 2011年第8期19卷 551-560页

作者： Wang, Jun Huang, Bormin Wu, Jiaji Chong, Jong-Wha Univ Wisconsin Space & Engn Ctr Madison WI 53706 USA Xidian Univ Sch Elect Engn Xian Peoples R China Hanyang Univ Dept Elect & Comp Engn Seoul 133817 South Korea

Overdrive is commonly used to reduce the liquid-crystal response time and motion blur in liquid-crystal displays (LCDs). However, overdrive requires a large frame memory in order to store the previous frame for reference. In this paper, a lapped transform-based codec (LTC) is proposed to reduce the frame memory needed for LCD overdrive. In the latest literature, a directional prediction-based codec (DPC) employs eight directional predictions, which takes up a large percentage of the computational complexity of the codec and does not consider the de-correlation of the inter-blocks. Therefore, the LTC first uses the lapped transform to decompose the correlation of the inter-blocks in the YUV color space. A hadamard transform is then used for energy compaction. The reordered coefficients are pre-quantized and encoded using the proposed adaptive bit-plane coding (ABPC) method for a simple hardware implementation. The simulation results show that the proposed LTC significantly improves the DPC in both subjective and objective performance and outperforms the block truncation coding (BTC) and adaptive multi-level BTC (AM-BTC), which have been described in the literature.

关键词： block truncation coding color image compression adaptive quantization coding LCD overdrive

来源：评论

学校读者我要写书评

暂无评论

A Blind Image Watermarking Scheme Utilizing BTC Bitplanes

引用

INTERNATIONAL JOURNAL OF DIGITAL CRIME AND FORENSICS 2011年第4期3卷 42-53页

作者： Yang, Chun-Ning Lu, Zhe-Ming Zhejiang Univ Sch Aeronaut & Astronaut Hangzhou Zhejiang Peoples R China

This paper presents a novel image watermarking scheme utilizing block truncation coding (BTC). This scheme uses BTC to guide the watermark embedding and extraction processes. During the embedding process, the original cover image is first partitioned into non-overlapping 4x4 blocks. Then, BTC is performed on each block to obtain its BTC bitplane, and the number of '1's in the bitplane is counted. If the watermark bit to be embedded is '1' and the number of '1's is odd, or the watermark bit to be embedded is '0' and the number of '1's is even, then no change is made. Otherwise, by changing at most three pixels in the original image block, the number of '1's (or '0's) in the renewed bitplane are forced to be odd for the watermark bit '1' or to be even for the watermark bit '0'. During the extraction process, BTC is first performed on each block to obtain its bitplane. If the number of '1's in the bitplane is odd, then the embedded watermark bit is '1'. Otherwise, the embedded watermark bit is '0'. The experimental results show that the proposed watermarking method is semi-fragile except for the changes in brightness and contrast;therefore, the proposed method can be used for image authentication.

关键词： Blind Watermarking block truncation coding Content Authentication Fragile Image Watermarking Information Hiding

来源：评论

学校读者我要写书评

暂无评论

Colour image retrieval using pattern co-occurrence matrices based on BTC and VQ

引用

ELECTRONICS LETTERS 2011年第2期47卷 100-+页

作者： Yu, F.-X. Luo, H. Lu, Z. -M. Zhejiang Univ Sch Aeronaut & Astronaut Hangzhou 310027 Peoples R China

Proposed is an effective feature for colour image retrieval based on block truncation coding (BTC) and vector quantisation (VQ). Each input colour image is decomposed into Y, Cb and Cr components. BTC is performed on the 4 x 4 Y blocks, obtaining a mean pair sequence and a bitplane sequence, and then they are quantised with the contrast pattern codebook and visual pattern codebook to obtain the contrast and visual pattern co-occurrence matrix. VQ is performed on the 4 x 4 Cb blocks and Cr blocks with the Cb codebook and Cr codebook, respectively, to obtain the colour pattern co-occurrence matrix. Retrieval simulation results show that, compared with two existing BTC-based features, the proposed feature can greatly improve retrieval performance.

关键词： BTC VQ bitplane sequence block codes block truncation coding colour image retrieval contrast pattern codebook feature extraction feature retrieval image coding image colour analysis image retrieval matrix algebra mean pair sequence pattern clustering pattern co-occurrence matrices vector quantisation vector quantisation visual pattern codebook

来源：评论

学校读者我要写书评

暂无评论

Multiple images embedding scheme based on moment preserving block truncation coding

引用

FUNDAMENTA INFORMATICAE 2006年第3期73卷 373-387页

作者： Hu, Yu-Chen Providence Univ Dept Informat Engn Taichung 433 Taiwan

A low-complexity grayscale image embedding scheme that can embed multiple secret images is proposed in this paper. In this scheme, different users can extract different secret images according to the secret keys they hold. To reduce the storage cost of the secret images, each of the secret images is first compressed using an improved version of the moment preserving block truncation coding scheme. The compressed message of each secret image is then encrypted by the DES cryptography system with different secret key and then embedded into the host image using the modulus least-significant-bit substitution technique. According to the experimental results, it is shown that the proposed scheme consumes a little computational cost. Besides, different users can extract different number of secret images. In other words, the proposed scheme indeed provides a good approach for the hiding of grayscale images with access control.

关键词： image hiding block truncation coding DES

来源：评论

学校读者我要写书评

暂无评论

A novel color image hiding scheme using block truncation coding

引用

FUNDAMENTA INFORMATICAE 2006年第4期70卷 317-331页

作者： Hu, Yu-Chen Lin, Min-Hui Jiang, Ji-Han Providence Univ Dept Comp Sci & Informat Engn Taichung 407 433 Taiwan Providence Univ Dept Comp Sci & Informat Management Taichung 407433 Taiwan Natl Formosa Univ Sci & Technol Dept Comp Sci & Informat Engn Yunlin 63208 Taiwan

In this paper, a novel color image hiding scheme that is capable of hiding two color secret images into a color host image is proposed. The secret images to be embedded are first compressed by the single bit map block truncation coding. DES encryption is then conducted on the compressed message before the secret image is embedded into the rightmost 3, 2, 3 bits of the R, G, B channels of every pixel in the host image. The experimental results show that our scheme provides an average secret image quality of 29.220 dB. In addition to the improved quality of both host images and retrieved secret images, our scheme further strengthens the protection of the secret images by conducting image compression and DES encryption on the secret image in advance. Therefore, our scheme not only extends the hiding capability of host images, but also is practical and secure.

关键词： steganography color image hiding block truncation coding DES

来源：评论

学校读者我要写书评

暂无评论

On-chip frame memory reduction using a high-compression-ratio codec in the overdrives of liquid-crystal displays

引用

OPTICAL ENGINEERING 2010年第11期49卷 117005-117005页

作者： Wang, Jun Min, Kyeong-yuk Chong, Jong-Wha Hanyang Univ Dept Elect & Comp Engn Seoul 133791 South Korea

Overdrive is commonly used to reduce the liquid-crystal response time and motion blur in liquid-crystal displays (LCDs). However, overdrive requires a large frame memory in order to store the previous frame for reference. In this paper, a high-compression-ratio codec is presented to compress the image data stored in the on-chip frame memory so that only 1 Mbit of on-chip memory is required in the LCD overdrives of mobile devices. The proposed algorithm further compresses the color bitmaps and representative values (RVs) resulting from the block truncation coding (BTC). The color bitmaps are represented by a luminance bitmap, which is further reduced and reconstructed using median filter interpolation in the decoder, while the RVs are compressed using adaptive quantization coding (AQC). Interpolation and AQC can provide three-level compression, which leads to 16 combinations. Using a rate-distortion analysis, we select the three optimal schemes to compress the image data for video graphics array (VGA), wide-VGA LCD, and standard definition TV applications. Our simulation results demonstrate that the proposed schemes outperform interpolation BTC both in PSNR (by 1.479 to 2.205 dB) and in subjective visual quality. (C) 2010 Society of Photo-Optical Instrumentation Engineers. [DOI: 10.1117/1.3509370]

关键词： block truncation coding color image compression adaptive quantization coding LCD overdrive

来源：评论

学校读者我要写书评

暂无评论

High Performance Overdrive Using Improved Motion Adaptive Codec in LCD

引用

IEEE TRANSACTIONS ON CONSUMER ELECTRONICS 2009年第1期55卷 20-26页

作者： Wang, Jun Chong, Jong-Wha Hanyang Univ Dept Elect & Comp Engn Seoul 133791 South Korea

To improve overdrive performance in LCD, we present an improved motion adaptive codec (IMAC). The IMAC contains two approaches to improve the motion adaptive codec overdrive (MAC-OD). The first is an advanced hybrid image codec (AHIC) for the efficient reduction of the image data stored in frame memory. The second is an advanced motion adaptive selector to reduce the overdrive error. The simulation results show that the IMAC at 6.04:1 compression ratio significantly improves the overdrive performance by 2.268dB in PSNR and achieves better visual quality compared with the conventional MAC-OD at 4:1 compression ratio. The IMAC is implemented with the Verilog HDL and fully synthesizable. It can be applied to shot-ten liquid crystal response time and minimize motion blur of LCD in TV and desktop applications(1).

关键词： LCD overdrive motion adaptive codec block truncation coding adaptive quantization coding

来源：评论

学校读者我要写书评

暂无评论

Majority-Parity-Guided Watermarking for block-Truncated Images

Majority-Parity-Guided Watermarking for Block-Truncated Imag...

引用

The Fifth International Conference on Information Assurance and Security(第五届信息保障与安全国际会议)

作者： Jing-Ming Guo Yun-Fu Liu Department of Electrical Engineering National Taiwan University of Science and Technology Taipei Taiwan

ISBN: (纸本)9780769537443

In this paper, a watermarking scheme, called Majority-Parity-Guided Error-Diffused block truncation coding (MPG-EDBTC), is proposed to achieve with high image quality and embedded capacity. The main problem of traditional BTC is its poor quality over configurations of high compression ratio. To overcome such problem, the extreme pixel values are employed to substitute both high and low means. The quantized error is also compensated by adjusting the neighboring pixels. With these strategies, the image quality and processing efficiency are improved. Moreover, the watermark is embedded by evaluating the parity value in a pre-defined Parity-Check Region (PCR). As seen in the experimental results, the proposed scheme can provide good robustness, image quality, and processing efficiency. Finally, the proposed MPG-EDBTC is extended to embed multiple watermarks and achieves excellent image quality, robustness, and capacity as well. Nowadays, most multimedia is stored in compressed format. It is more appropriate to embed information such as watermarks in compressed domain. The proposed method has been proved to solve effectively the inherent problems in traditional BTC, and provide excellent performance in watermark embedding.

关键词： block truncation coding error diffusion digital watermarking digital halftoning

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：