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 i...
详细信息
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).
A novel image authentication scheme which can protect the image integrity of the compressed images for block truncation coding (BTC) is proposed in this paper. In the proposed scheme, the authentication codes are embe...
详细信息
A novel image authentication scheme which can protect the image integrity of the compressed images for block truncation coding (BTC) is proposed in this paper. In the proposed scheme, the authentication codes are embedded into the the quatization levels of each BTC-compressed image block by using reference matrix- RM (B) . The size of the authentication codes can be decided according to the user's requirement by adjusting the value of B in Reference Matrix. The experimental results demonstrate that the proposed method outperforms previous approaches in image quality of the embedded image and high detecting accuracy.
In this paper, we propose a reversible steganographic algorithm for compressed images. The algorithm firstly compresses the input image using block truncation coding. One binary map and two quantisation levels, called...
详细信息
In this paper, we propose a reversible steganographic algorithm for compressed images. The algorithm firstly compresses the input image using block truncation coding. One binary map and two quantisation levels, called high and low levels, are then obtained for each block. Thereafter, we adopt a median edge detector to predict the high and low quantisation levels for neighbouring blocks. A secret message is then embedded into the predicted difference based on the difference expansion technique. Each block can be classified as embeddable and nonembeddable according to the order of two quantisation levels. Thus, the location map is unnecessary in our proposed algorithm. The experimental results show that our data-embedded compressed code can be the same file size compared with standard block truncation coding-compressed code. Our algorithm can also resist the RS steganalysis attack. Further, the embedding capacity can be varied according to the given embedding parameter. The feasibility of our proposed algorithm is validated by presenting comparisons with existing algorithms.
In this paper, an algorithm for digital image watermarking based on discrete wavelet transforms ( DWT) and block truncation coding ( BTC) has been proposed. In the embedding process, the host image is decomposed into ...
详细信息
In this paper, an algorithm for digital image watermarking based on discrete wavelet transforms ( DWT) and block truncation coding ( BTC) has been proposed. In the embedding process, the host image is decomposed into first level DWT and the watermark image is compressed by BTC. The compressed watermark is then embedded into the selected sub-band of the host image. The proposed method has been extensively tested against numerous known signal processing attacks and has been found to be robust and highly imperceptible. Further, the performance of the algorithm has been tested with fractal compression technique. The performance of the BTC-based technique is better than the fractal-based compression techniques in terms of robustness and imperceptibility.
A novel data hiding method for Absolute Moment block truncation coding (AMBTC) compressed image based on quantization level modification is proposed. blocks of AMBTC-compressed image are classified into two categories...
详细信息
A novel data hiding method for Absolute Moment block truncation coding (AMBTC) compressed image based on quantization level modification is proposed. blocks of AMBTC-compressed image are classified into two categories, namely smooth and complex, according to a predefined threshold. For smooth blocks, the bitmap is replaced by secret data for data embedment. Meanwhile, the corresponding quantization levels are modified to achieve a minimum distortion. If a larger payload is required, the modified quantization levels can be further perturbed for carrying two additional bits. If the blocks are complex, one data bit can be embedded with no distortion by swapping the values of the two quantization levels together with bitmap flipping. In addition, a suppress threshold mechanism is used to prevent from the application of the perturbation technique at low payload to maintain the image quality. The proposed method minimizes the distortion of each stego block while ensuring high payload, thus the embedding efficiency can be enhanced. Experimental results demonstrate the improvement of the proposed method compared with other related state-of-art works.
To protect the image integrity of the compressed images for block truncation coding (BTC), an image authentication scheme is proposed in this paper. In this scheme, the authentication data of each compressed image blo...
详细信息
To protect the image integrity of the compressed images for block truncation coding (BTC), an image authentication scheme is proposed in this paper. In this scheme, the authentication data of each compressed image block is generated from the random value induced by the predefined random seed. The size of the authentication data can be selected according to the user's requirement. Then, the authenticaiton data is embedded into the difference value between the quantization levels of each BTC-compressed image block. The experimental results reveal that the proposed scheme performs well in terms of detection precision and the embedded image quality.
This paper presents a novel hardware-oriented image compression algorithm and its very large- scale integration (VLSI) implementation for wireless sensor networks. The proposed novel image compression algorithm consis...
详细信息
This paper presents a novel hardware-oriented image compression algorithm and its very large- scale integration (VLSI) implementation for wireless sensor networks. The proposed novel image compression algorithm consists of a fuzzy decision, block partition, digital halftoning, and block truncation coding (BTC) techniques. A novel variable-size block partition technique was used in the proposed algorithm to improve image quality and compression performance. In addition, eight different types of blocks were encoded by Huffman coding according to probability to increase the compression ratio further. In order to achieve the low-cost and low-power characteristics, a novel iteration-based BTC training module was created to get representative levels and meet the requirement of wireless sensor networks. A prediction and a modified Golomb-Rice coding modules were designed to encode the information of representative levels to achieve higher compression performance. The proposed algorithm was realized by a VLSI technique with an UMC 0.18-mu m CMOS process. The synthesized gate counts and core area of this design were 6.4 k gate counts and 60 000 mu m2, respectively. The operating frequency and power consumption were 100 MHz and 3.11 mW respectively. Compared with previous JPEG, JPEG-LS, and fixed-size BTC-based designs, this work reduced 20.9% gate counts more than previous designs. Moreover, the proposed design required only a one-linebuffer memory rather than a frame-buffer memory required by previous designs.
In this paper, we present a new algorithm that utilizes mathematical morphology for pyramidal coding of color images. We obtain lossy color image compression by using block truncation coding at the pyramid levels to a...
详细信息
In this paper, we present a new algorithm that utilizes mathematical morphology for pyramidal coding of color images. We obtain lossy color image compression by using block truncation coding at the pyramid levels to attain reduced data rates. The pyramid approach is attractive due to low computational complexity, simple parallel implementation, and the ability to produce acceptable color images at moderate data rates. In many applications, the progressive transmission capability of the algorithm is very useful. We will show experimental results for color images at data rates of 1.89 bits/pixel.
This paper presents an information hiding method in the BTC-compressed domain based on histogram modification and visual cryptography. By using the visual cryptography algorithm, the secret image is divided into sever...
详细信息
This paper presents an information hiding method in the BTC-compressed domain based on histogram modification and visual cryptography. By using the visual cryptography algorithm, the secret image is divided into several transparencies, which are called shared images. Then, one shared image is embedded into the BTC-compressed data through histogram modification which is a reversible information hiding algorithm. When there is any need to recover the secret image, the shared image which formerly embedded into the BTC-compressed data can be extracted. Stacking the embedded shared image and the shared image we have already known, the secret image can be recovered. Experimental results demonstrate the feasibility of the proposed method, and the tampering location ability is quite good.
As one of the famous block-based image coding schemes,block truncation coding(BTC) has been also applied in digital *** BTC-based watermarking or hiding schemes usually embed secret data by modifying the BTC encoding ...
详细信息
As one of the famous block-based image coding schemes,block truncation coding(BTC) has been also applied in digital *** BTC-based watermarking or hiding schemes usually embed secret data by modifying the BTC encoding stage or BTC-compressed data,obtaining the watermarked image with poorer quality than the BTC-compressed *** paper presents a new oblivious image watermarking scheme by exploiting BTC *** the traditional schemes,our approach does not really perform the BTC compression on images during the embedding process but utilizes the parity of the number of horizontal edge transitions in each BTC bitmap to guide the watermark embedding and extraction *** embedding process starts by partitioning the original cover image into non-overlapping 4×4 blocks and performing BTC on each block to obtain its BTC *** watermark bit is embedded in each block by modifying at most three pixel values in the block to make sure that the parity of the number of horizontal edge transitions in the bitmap of the modified block is equal to the embedded watermark *** the extraction stage,the suspicious image is first partitioned into non-overlapping 4×4 blocks and BTC is performed on each block to obtain its ***,by checking the parity of the number of horizontal edge transitions in the bitmap,we can extract one watermark bit in each *** results demonstrate that the proposed watermarking scheme is fragile to various image processing operations while keeping the transparency very well.
暂无评论