New Publications are available for Image and video coding
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New Publications are available now online for this publication.
Please follow the links to view the publication.Inter-description motion vector redundancy control for scalable multiple description video coding
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0429
The problem of inter-description motion vector redundancy control in scalable multiple description video coding is addressed in this paper. In the motion compensated temporal filtering (MCTF) followed by the multiple description scalar quantization (MDSQ) of texture data approach, the same set of motion vectors are repeated in both descriptions. While this repetition of motion vector data adds extra overhead, they do not contribute to self correcting of errors as in MDSQed texture data during joint decoding. The paper proposes interleaving of motion vector fields between the descriptions and MDSQ of motion vectors to obtain two correlating motion vector fields rather than repeating them. The results show superior performance of MDSQ of motion vectors compared to other approaches. (5 pages)Surrey University Library for Forensic Analysis (SULFA) of video content
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0422
In this paper we propose SULFA (Surrey University Library for Forensic Analysis) for the benchmarking of video forensic techniques. This new video library has been designed and built for the purpose of video forensics specifically related to camera identification and integrity verification. As far as we know, no such library or similar currently exists in the community. SULFA contains original as well as forged video files, which will be freely available through the University of Surrey's website. There are approximately 150 videos collected from three camera sources, which are Canon SX220 (codec H.264) [1], Nikon S3000 (codec MJPEG) [2] and Fujifilm S2800HD (codec MJPEG) [3]. Each video is approximately 10 seconds long with resolution of 320×240 and 30 frames per second. All videos have been shot after carefully considering both temporal and spatial video characteristics. In order to present life-like scenarios, various complex and simple scenes have been shot with and without using camera support (tripod). Furthermore 9 original videos from each source in SULFA have been tested with Photo Response Non Uniformity (PRNU) based camera identification methods. Currently, SULFA also includes videos with cloning or copy-paste forgery. Each forged video includes full information of the doctored region. (5 pages)High-capacity colour image watermarking using multi-dimensional Fourier transforms and semi-random LDPC codes
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0456
In this paper, we propose a colour image watermarking scheme based on the Spatio-Chromatic Fourier Transform (SCFT) with spread-spectrum signaling enhanced by error correction using semi-random low density parity check (SRLDPC) codes. The SCFT transform enables efficient use of the embedding properties of the complex Fourier representations without incurring additional computational complexity. The watermark detection is based on a statistical maximum likelihood approach using a Weibull distribution known to be well-suited for modelling the SCFT coefficients. The proposed embedding scheme is image-adaptive, and provides control over the watermark embedding strength according to the local properties of the SCFT representation of the host image. The efficiency and data hiding capacity of the proposed watermark embedding scheme are found to be greatly enhanced by the use of SR-LDPC codes. Simulation results and comparisons with colour-component Discrete Fourier Transform (DFT)-based schemes demonstrate the increased robustness of the proposed LDPC-coded, colour image watermarking algorithm against standard attacks including additive white Gaussian noise and JPEG compression. (5 pages)Robust image watermarking using two dimensional Walsh coding
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0435
This paper deals with a new blind watermarking technique using two dimensional Walsh coding. The aim of using the 2D Walsh coding is to improve the robustness of the algorithm. The watermark which is a hand written signature was encoded by using 2D Walsh functions then it was embedded in the low frequency coefficients of the discrete cosine transform of the host image. The new algorithm is blind and does not require the original image to extract the watermark and cause minimal distortion to the host image. The robustness of the algorithm was assessed against various Stirmark attacks such as JPEG compression, noise, and some filtering operations. The extent of the improvements is related to the scaling factor. (5 pages)Dyadic wavelets and dct based blind copy-move image forgery detection
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0439
This paper proposes a blind method of copy move image forgery detection using dyadic wavelet transform (DyWT) and discrete cosine transform (DCT). An input image is decomposed using DyWT to approximation (LL) subbands and detail (HH) subbands. DCT is then applied to overlapping blocks in LL and HH subbands, and Euclidean distances between the blocks are calculated using DCT coefficients. Decision is made based on similarity of the blocks in LL subband and dissimilarity of the blocks in HH subband. The proposed method is evaluated with images of different sizes, different compression qualities, and with or without rotation before pasting. Experimental results show that the method performs better in all cases than two other multiresolution based methods. (6 pages)Multi-resolution, perceptual and compressive sampling based image codec
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0462
Direct application of compressive sampling in coding wavelet high frequency coefficients of an image, is unpleasantly deteriorating the quality of the reconstructed image. This is due to an error introduced by many high frequency coefficients that have small but nonzero values. In this paper, a novel multi-resolution image coding scheme using compressive sampling and perceptual weights is presented that significantly improves the quality of the reconstructed images by setting the coefficients with small values to zero using two different hard thresholding operators. The proposed codec applies a wavelet transform on the input image and decorrelates the image into its frequency subbands. Baseband coefficients are lossless coded to preserve their visually important information. High frequency subbands' coefficients are hard threshold to improve and also to control their sparsity. Perceptual-weights for different wavelet subbands are calculated and used to adjust threshold values for different subbands. Compressive sampling algorithm is used to generate measurements for each resulting sparse subband. Measurements for each subband are then cast to an integer and arithmetic coded. In the decoder side, the Basis Pursuit method is used to recover the coefficients. Empirical values for the observation factor for best coding performance of the codec, using standard test images, were first determined. The performance of the codec was assessed using standard test images. Results show that the application of perceptual weights in regulating threshold values significantly improves the coding performance of the codec. (4 pages)Distortion constrained robustness scalable watermarking
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0434
The embedding distortion and the robustness to quality scalable image coding are two complementary watermarking requirements. This work proposes a novel concept of scalable image watermarking to generate a distortion-constrained robustness scalable watermarked image code stream which consists of hierarchically nested joint distortion-robustness coding atoms. The code stream is generated using a new wavelet domain binary tree guided rules-based blind watermarking algorithm. The code stream can be truncated at any distortion-robustness atom level to generate the watermarked image with the desired distortion-robustness requirements. A universal blind extractor is capable of extracting watermark data from the watermarked images. The simulation results verify the feasibility of the proposed concept, its applications and its improved robustness to quality scalable content adaptation (JPEG 2000). (6 pages)A combined image approach to compression of volumetric data using delaunay tetrahedralization
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0461
We present a method for lossy compression of three dimensional gray scale images that is based on a 3D linear spline approximation to the image. We have extended an approach that has previously been successfully applied in two dimensions. In our method, we first select significant points in the data, and use them to create a 3D tetrahedralization. The tetrahedrons of the tetrahedralization are used as cells for a linear interpolation spline that gives an approximation of the original image. The compression is done by storing the positions of the vertices of the tetrahedralization and the values there instead of the value of the approximation at each grid point. We introduce a novel concept of using a smoothed version of the original image to improve the quality of the approximating spline. To increase the efficiency of the algorithm, we combine it with a refinement/decimation technique. We compare our compression technique to JPG2000 3D. We show that our algorithm performs similarly to, and in some cases even outperforms it, for high compression ratios. Our approach gives images that have significantly different properties than ones created using wavelets, and have the potential of being more suitable for some applications. In addition, this type of compression is particularly suitable for visualization. (6 pages)Adaptive GOP-length multiple representation coding for error-resilient video delivery
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0430
Multiple Representation Coding (MRC) is a novel scheme that can enable error-resilient video delivery over channels prone to burst or signal losses. In the MRC scheme, the source video is decomposed into multiple independently decodable representations. These multiple representations are then transmitted as a single video stream using a `GOP interleaving' (GOP: Group of Pictures) mechanism. The GOP interleaver disperses the multiple representations within the transmitted stream so that the spatio-temporally co-located segments of the sequence belonging to different representations are not simultaneously impaired by the same burst loss. When the transmitted bitstream is impaired by a burst loss spanning multiple frames, the MRC scheme can give a PSNR gain on the order of 2-4 dBs over the conventional full-size encoding and transmission of the video. Further, the error-robustness of the MRC scheme can be improved by increasing the length of the representation segments interleaved in the transmitted stream. In this paper, we propose adapting the GOP-length of individual representations in response to the expected length of the burst loss over the network. Simulation results demonstrate that the adaptive MRC scheme can give a PSNR gain of around 2 dB over the non-adaptive MRC scheme, in presence of long burst errors or signal loss intervals. (6 pages)Low-complexity lossy image coding through a near-optimal general embedded quantizer
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0428
Embedded quantization is a mechanism employed by many lossy image codecs to progressively refine the distortion of a (transformed) image. Currently, the most common scheme to do so is to use a uniform scalar deadzone quantizer (USDQ) together with a bitplane coding (BPC) strategy. This scheme is convenient, but does not allow major variations. This paper uses the recently introduced general embedded quantizer (GEQ) to design a multi-stage quantization scheme that can be introduced in the core of modern image coding systems. Experimental results carried out in the framework of JPEG2000 indicate that the proposed scheme achieves same coding performance as that of USDQ+BPC while requiring fewer quantization stages, which reduces the computational costs of codecs without penalizing their performance. (6 pages)Depth estimation from a video sequence with moving and deformable objects
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0425
In this paper we present an algorithm for depth estimation from a monocular video sequence containing moving and deformable objects. The method is based on a coded aperture system (i.e., a conventional camera with a mask placed on the main lens) and it takes a coded video as input to provide a sequence of dense depth maps as output. To deal with nonrigid deformations, our work builds on the state-of-the-art single-image depth estimation algorithm. Since single-image depth estimation is very ill-posed, we cast the reconstruction task as a regularized algorithm based on nonlocal-means filtering applied to both the spatial and temporal domain. Our assumption is that regions with similar texture in the same frame and in neighbouring frames are likely to belong to the same surface. Moreover, we show how to increase the computational efficiency of the method. The proposed algorithm has been successfully tested on challenging real scenarios. (6 pages)Digital image ownership verification based on spatial correlation of colors
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0448
In this paper, a spatial domain digital image copyright protection scheme based on Visual Cryptography (VC) and Spatial Correlation of Colors (SCC) is proposed. A binary feature matrix, extracted from the spatial correlation of host image, is used to split the watermark into two noisy binary images called shares. One of them is generated during watermark embedding phase and is registered with a trusted third party. The other is extracted during watermark extraction phase. Both these shares are combined to recover hidden watermark. When compared to the related works, the proposed scheme reduces the probability of false positives; reduces the size of shares and improves the quality of extracted watermark. Experimental results prove that the scheme is also robust to wide range of attacks. (5 pages)High precision and low power DCT architectures for image compression applications
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0460
The computation of two-dimensional Discrete Cosine Transform (2-D DCT) in image and video compression standards involves specific level of precision and high degree of complexity. This paper introduces two architectures, taking into consideration accuracy, power consumption and speed. The proposed architectures are implemented using the Xilinx system generator on the Virtex5 5vlx50tff1136-3 Xilinx platform and tested upon six standard images. The proposed architectures partition the input image into blocks of (8×8) pixels to compute 2-DDCT of each block sequentially. The results obtained revealed that the proposed architectures produced very good image quality, with 53 to 79 dB PSNR for the first standard image (Lena Image) and a word length of two and three bytes, respectively. The architectures are capable of operating up to 171 MHz at a word length of two bytes and the total memory used was 36 KB. In addition, the dynamic power consumption for first and second architecture are 60 and 38m W, respectively at 10 ns. (6 pages)Robust watermarking for scalable image coding-based content adaptation
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0436
In scalable image coding-based content adaptation, such as, JPEG 2000, the quality scaling is performed by a quantization process that follows a bit plane discarding model. In this paper we propose a robust blind image watermarking algorithm by incorporating the bit plane discarding model. The new wavelet based binary tree guided rules-based watermarking algorithm is capable to retain the watermarking information for a given number of bit plane being discarded. The experimental simulations confirm the scheme's robustness against JPEG 2000 quality scalability. (6 pages)Scalable fusion using a 3D dual tree wavelet transform
http://dl-live.theiet.org/content/conferences/10.1049/ic.2011.0172
This paper introduces a novel system that is able to fuse two or more sets of multimodal videos in the compressed domain. This is achieved without drift and produces an embedded bitstream that offers fine grain scalability. Previous attempts to fuse in the compressed video domain have been not been possible due to the complications of predictive loops within standard video encoding techniques. The compression system is based on an optimised spatio-temporal codec using the 3D Discrete Dual-tree Wavelet Trans- form (DDWT) together with bit plane encoding method SPIHT and a coefficient sparsification process (noise shaping). Together, these methods are able to efficiently encode a video sequence without the need for motion compensation due to the directional (in space and time) selectivity of the transform. This enables scalable compressed domain fusion without drift. This results in extremely flexible fusion scenarios in dynamic bandwidth environments where there are variable client receiving capabilities. (5 pages)Wyner-Ziv coding for distributed compressive sensing
http://dl-live.theiet.org/content/conferences/10.1049/ic.2011.0141
Distributed compressive sensing (CS) is emerging as a powerful technique of distributed signal processing in various applications such as sensor networks due to its capability of simultaneous sensing and compression. However, since distributed CS is an analog technique, a fundamental open question is to find the best source coding scheme for the distributed CS samples. This paper applies nested-lattice Wyner-Ziv coding to the CS data by exploiting the correlation among the CS samples at different sensors. The proposed coder consists of CS with Toeplitz/circulant sensing matrices and practical Wyner-Ziv coding. Simulation results shows this is a fast, energy-saving system and recovers good quality image sources with low distortion and high SNR. (5 pages)Optimal implementation of digital steganography in an true color images for the secrete communication
http://dl-live.theiet.org/content/conferences/10.1049/ic.2011.0057
A Real life requirement motivated this case study for secure the digital communication. Hiding data with security is the highly challenging and desirable task. The purpose of this research work is to develop a secure and optimal data hiding technique in 24 bit hue color image .My proposed method is flexible on size of secret message bits and allows us to embed a large amount of secret messages as well as maintaining good visual quality of stego-image. Using this method, message bits are embedded into uncertain and higher LSB layers, resulting in increased imperceptible and robustness of stego-image.Fractal image compression using block indexing technique
http://dl-live.theiet.org/content/conferences/10.1049/ic.2011.0092
Fractal technique is based on the self similarities in the image. The main objective is to reduce the encoding time by using a technique called Block Indexing Technique (BIT), based on histogram characteristics to reduce the redundancy information in an image, which leads to reduction of the number of range blocks.High-capacity reversible q-ry data hiding with location map-free capability
http://dl-live.theiet.org/content/conferences/10.1049/ic.2011.0136
This paper proposes a high capacity and high quality image data hiding scheme based on a causal predictor, predictor error expansion and a local activity indicator. The utilization of the secret data from Galois field GF(q), q 2 allows to embed more than one bit per pixel in compliance with a high quality of stego image. Moreover, special conditions for location map-free embedding are derived. Experimental analysis demonstrates the effectiveness of the proposed approach in achieving the high embedding capacity along with the high image fidelity. (6 pages)Neural network based approach for MPEG video traffic prediction
http://dl-live.theiet.org/content/conferences/10.1049/ic.2011.0041
In the near future, video is going to be the major Internet traffic and the most popular standard used to transport and view video is MPEG. The MPEG traffic is VBR (variable bit rate) traffic & in the form of a time-series representing frame/VOP (video object planes) sizes. Video traffic prediction and modeling is important in enhancing the reliable operation over these networks. In this paper, the MPEG-4 VBR video traffic is predicted by ANN (Artificial Neural Network). The arm is to predict the future frame of video stream. In single frame prediction problem, the information of previous frame sizes is used to predict the next frame size of the sequence. As a tool for the prediction, we use neural network - multilayer perception feed forward neural network. (FMLP). The prediction results of neural network have compared with the traditional averaging method. The results show that the neural approach is best as compared to averaging approach.Extended visual cryptography scheme with an artificial cocktail party effect
http://dl-live.theiet.org/content/conferences/10.1049/ic.2011.0114
Visual cryptography schemes have been introduced in 1994 by Naor and Shamir [9]. These kind of schemes have been also well described by C. Blundo, A. De Santis and D.R. Stinson in [3]. In this case, a secret image I may be encoded into n shadow images called the shares, and to give exactly one such shadow image to each member of a group P of n persons. Certain qualified subsets of participants can visually recover I, but other, forbidden sets of participants have no information on I. A visual recovery for a set X consists of photocopying the shares given to the participants and then stacking them. Shortly afterwards the discovery of visual cryptography schemes Droste gave a generalization of such schemes, and Ateniese et al, formalized the idea of Naor and Shamir of an extension of the model which conceals the very existence of the secret image. Ateniese et al have called this formalization, Extended Visual Cryptography [5, 7,10]. In order to encode and hide a given set I<sub xmlns="http://pub2web.metastore.ingenta.com/ns/">1</sub>, I<sub xmlns="http://pub2web.metastore.ingenta.com/ns/">2</sub>, . . . , I<sub xmlns="http://pub2web.metastore.ingenta.com/ns/">k</sub> of gray-level images, in this paper, we propose an Extended Visual Cryptography Scheme for which the decoding process simulates a cocktail party effect. (10 pages)Performance improvement of hybrid image coding using lifting wavelet transform and Contourlet decomposition
http://dl-live.theiet.org/content/conferences/10.1049/ic.2011.0088
This paper proposes a method to improve the performance of hybrid image compression technique by combining lifting wavelet transform and contourlet decomposition. This proposed method takes advantage on each technique, the high compression ratio that can be provided by contourlet decomposition and the infinite peak-to-peak signal to-noise ratio (PSNR) that can be provided by lossless lifting transform. The experiment results show that with this hybrid method, we can get an infinite PSNR (no data losses) with higher compression ratio comparing to usual lossless and lossy methods. It is expected that this method is suitable for compressing aerial photographs in terms of image reconstruction quality, compression ratio and processing time. This improvement is considerably interesting because we can save the storage space and data transmission tune without any data losses.Design and ASIC implementation of 2-d DWT IDWT
http://dl-live.theiet.org/content/conferences/10.1049/ic.2011.0063
In this paper, high-efficient lifting-based architectures for the 5/3 discrete wavelet transform (DWT) are proposed. Filter coefficients of the biorthogonal 5/3 wavelet low-pass filter are quantized before implementation in the high-speed computation hardware. In the proposed architecture, all multiplications are performed using less shifts and additions. The digital signal represented in time-scale obtained by using digital filtering techniques is known as Discrete Wavelet Transform. Here the signal to be analyzed is passed through filters with different cutoff frequencies at different scales. The DWT is computed by successive lowpass and highpass filtering of the discrete time-domain signal. The efficient architecture had been chosen for lifting scheme based DWT/IDWT process and modeled in Verilog with synthesis point of view. To meet the standards of quality, ICs should be thoroughly tested, where the necessity of suitable DFT scans arises. The estimated dynamic power consumption is 2.81mW and leakage power is 20.370uW.Comparison of algorithms for image compression
http://dl-live.theiet.org/content/conferences/10.1049/ic.2011.0094
The EZW and SPIHT coding are remarkably effective image compression algorithms having the property that the bits in the compressed bit stream are generated in the order of importance yielding a fully embedded code, hi this project the coding techniques for EZW (Embedded zero wavelet coding) and SPHIT (Set partitioning in hierarchical trees) have been developed. The performance analysis of both the algorithms in terms of compression ratio and peak signal to noise ratio (PSNR) for different level of Wavelet decomposition has been implemented with the comparison of results for the images This project provides an easy and efficient method for qualitative and quantitative comparison of different algorithms that can be used for image compression.Consistent quality control for wireless video surveillance using distributed video coding
http://dl-live.theiet.org/content/conferences/10.1049/ic.2011.0116
Distributed Video Coding (DVC) is well known for low complexity encoding which provides coding solutions for a wide range of applications, in particular wireless video surveillance. In this paper, we address the problem of distortion variation introduced by typical rate control algorithms, especially in a various bit rate environment. A distortion quantization model derived from a MPEG-2 distortion estimation model is proposed to achieve smooth picture quality across video frames. Simulation results show that the proposed quality control algorithm is capable to meet user defined target distortion and maintain a rather small variation for sequence with slow motion and performs similar to fixed quantization for fast motion sequence at the cost of some RD performance. (6 pages)A new algorithm for fast block-matching motion estimation based on tree-structured block partition
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0996
The fast block-matching motion estimation has been widely used in some low bit-rate video compression applications, owing to its simplicity and effectiveness. How ever, there are several problems with it, which are mainly caused by the employment of fixed block size. In this paper, a new algorithm for fast block- matching motion estimation based on tree-structured block partition is proposed which applies the variable block size (VBS) techniques in the block search. Simulation results show that, the algorithm block- searching efficiency as well as to improve the precision of block-searching.A hybrid image compression technique based on DWT and DCT transforms
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.1065
In this paper, a hybrid technique using the discrete cosine transform (DCT) and the discrete wavelet transform (DWT) is presented. We show evaluation and comparative results for DCT, DWT and hybrid DWT-DCT compression techniques. Using the Power Signal to Noise Ratio (PSNR) as a measure of quality, we show that DWT with a two-threshold method named "improved-DWT" provides a better quality of image compared to DCT and to DWT with a one-threshold method. Finally, we show that the combination of the two techniques, named improved-DWT-DCT compression technique, showing that it yields a better performance than DCT-based JPEG in terms of PSNR. (8 pages)A novel 8×8 transform method applied in video coding
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0846
Transform Coding has been playing an important role in video coding and increasingly becomes a research focus especially in the current popular standards such as H.264/AVC, AVS and HEVC. It is important to select an excellent transform method as transform module has a direct impact on the efficiency of video codec. This paper proposes a new 8×8 transform method as well as its integer approximation applied in video coding. Experiments show that it achieves a higher performance.Research on underground wireless video encoding algorithm based on region of interest for interprediction
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0992
The low illumination and odious environment in the coal mine underground have greatly affected the quality of video image. Aimed at the specialty that the background is unchanged basically at coal mine underground wireless video monitoring point with foreground objects moving only, the inter-prediction algorithm based on region of interest is brought forward in the article. By simulating, the algorithm could greatly reduce the complexity of video encoding and encoding rate, while the quality of video basically keeping unchanged or even enhanced.Research on wireless video encoding algorithm for underground based on background registration and motion segmentation
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0995
Regarding to the specialty that the background picture keeps unchangeable with perspective motion objects varying for wireless video monitoring of underground mines, the motion segmentation encoding based on background registration algorithm is brought forward in this article. In this motion segmentation algorithm, each frame for wireless underground video encoding is segmented by motion objects and background, then, they are processed and transmitted according to separated algorithm regulations. Furthermore, because of low illumination and image blurring, the image enhanced algorithm is integrated into the encoding process to enhance the main motion objects to improve the subject quality. At last, the real time transmitted motion object and local saved background image is integrated together to show on the terminal monitoring screen. By this algorithm, the complexity of video encoding and code rate is reduced with high definition video sequences.3-D DWT based multiple watermarking algorithm for spectral images
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0469
In this paper, we propose the multiple watermarking algorithm for spectral 3-D (3 Dimensional) images in the D WT (Discrete Wavelet Transform) domain. Haar wavelet based 3-D D WT is applied on spectral image. Eigen values of Dual binary watermarks are embedded in the mid frequency band, which are multiplied with appropriate strength factor. 3-D ID WT (Inverse D WT) is applied on the modified subbands to obtain the watermarked image. During extraction process, dual binary watermarks are reconstructed from the test image. An experimental result shows that the proposed algorithm produces very high imperceptibility and robustness against various types of attacks like rotation, addition of noise etc.The design and implementation of elevator monitoring system based on embedded platform
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0796
With the development of urbanization process and residential commercialization, a large number of high-rise buildings have been constructed. With the great increase of elevator quantity, we have to pay more attention to the safety of elevators. The remote elevator monitoring system can provide real-time view of the operating conditions, and control the running of the elevator. This paper is based on C/S (Client/Server) mode. It builds an elevator model based on the embedded development platform of ARM9 EBD9315. At the same time, we capture images with camera and perform JPEG compression to these images, and then transfer images and the elevator running data to control center for real-time display and so on. This paper proposed the elevator monitoring theoretical system, established the system framework, and tested the performance of this model.Complexity analysis of algorithm/architecture co-design for H.264 deblocking filter in MPSoC design
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0843
Due to the high computational and power consumption demands of modern embedded visual media processing, MPSoC architectures often contain multiple heterogeneous processing elements, which introduced numerous problems involving the mapping of algorithm functionality and possible refinements of each processing element. To cope with these challenges, algorithm and architecture co-design (AAC) is significant for characterizing the algorithmic complexity used to optimize targeted architecture. This paper proposes the efforts towards a systematic complexity analysis for AAC by timed mode of computing (MoC)-based analysis. Through such seamless approach, complexity measures intrinsic to the algorithm, such as degree of parallelism and pipeline depth, can be fully exploited. Furthermore, the resulting explicit architecture/algorithm friendliness will greatly help the mapping of algorithm to differential processing elements. As an example, an ideal architecture prototype of deblocking filter for H.264 was proposed, which can achieve 144 cycles/macroblock throughput, and also several deblocking filter designs in the literature have been compared and illustrated to demonstrate the benefits of analysis and exploitation of complexity measures with our approach in the early system-level design.ROI-based MB-level adaptive frequency weighting
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0991
In order to improve the subjective quality of video coding, satisfy the properties of human visual, and reduce the bitrate of coding, a ROI-based MB-Level Adaptive Frequency Weighting Scheme is proposed in this paper. In the perceptual video coding scheme, the visual attention and the frequency sensitivity are the most important properties of HVS and usually used to improve the subjective quality. In this paper, the spatial context, the side information and the properties of the human visual system are all taken into consideration. According to the effect of frequency weighting, three different strategies are defined, and the different areas in one picture can choose different frequency weighting strategies. The experimental results show that the proposed region of interest based MB-Level Adaptive Frequency Weighting algorithm (ROI-baesd MBAFW) can improve the subjective quality significantly. Additionally, compared with the no frequency weighting ROI-based MBAFW algorithm can achieve about 10% bitrate reductions with almost the same subjective quality.The rapid lossless compression of true colour image
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0893
To increase the compression ratio and decrease the complexity of algorithm when compressing the true colour image. An improved method is adopted based on colour components in current line. Then we make error predicting adaptively based on neural network, and then code them with Rice coding. Experiment shows that: this method is effective in compression ratio and its coding time is shorter.Optimal quantization for DC coefficient of Wyner-Ziv frame in unidirectional distributed video coding
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0839
This paper presents a rate-distortion based optimal quantization scheme for DC coefficient in the unidirectional Wyner-Ziv (WZ) video coding system. In the proposed scheme, a new rate-distortion (RD) model is developed to find out an optimal quantization step (OQS) for DC coefficient. More specifically, the effects of quantization step on both distortion and rate are considered in our presented RD model. And OQS, optimal in term of RD cost, can be solved for DC coefficient, at the expense of increasing the coding complexity slightly. The comparison of RD performance between the Wyner-Ziv video coding system using our proposed scheme and the baseline system without using OQS is presented. The results show that quantization with OQS for DC coefficient can improve the average PSNR of WZ frames by 0.3~1.0 dB.Multiple description image coding based on fast fractal coding
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.1001
Multiple description coding (MDC) is an effective method for robust transmission of image and video over unreliable networks. In this paper, a new multiple description image coding scheme based on fractal coding is proposed, which can satisfy the robust transmission in case of channel failure. In view of computation complexity of fractal image coding, Fine granularity successive elimination (FGSE) is applied to speed up the encoding process. Compared with the conventional scheme, the experimental results show that the proposed scheme can improve rate distortion performance efficiently and reduce the coding complexity simultaneously.Standard Codecs: Image compression to advanced video coding
http://dl-live.theiet.org/content/books/te/pbte054e
<p xmlns="http://pub2web.metastore.ingenta.com/ns/">A substantially updated edition of <i>Video Coding: An introduction to standard codecs</i> (IEE 1999, winner of IEE Rayleigh Award as the best book of 2000), this book discusses the growth of digital television technology, from image compression to advanced video coding. This third edition also includes the latest developments on H.264/MPEG-4 video coding and the scalability defined for this codec, which were not available at the time of the previous edition (IEE 2003). The book highlights the need for standardisation in processing static and moving images and extensively exploits the ITU and ISO/IEC standards defined in this field. The book gives an authoritative explanation of pictures and video coding algorithms, working from basic principles through to the advanced video compression systems now being developed. It discusses the reasons behind the introduction of a standard codec for a specific application and its chosen parameters. Each chapter is devoted to a standard video codec, and chapters are introduced in an evolutionary manner complementing the earlier chapters. This book will enable readers to appreciate the fundamentals needed to design a video codec for any given application and should prove a valuable resource for managers, engineers and researchers working in this field.</p>An improved Db2-based MCTF for scalable video coding
http://dl-live.theiet.org/content/conferences/10.1049/cp.2010.0680
MCTF (Motion Compensated Temporal Filtering) was firstly introduced in 3-D transform coding and has been used in several scalable coding proposals. The quality of the MCTF which plays an essential role in motion compensated 3-D subband/wavelet coding. The simplest implementation of MCTF in a lifting filter structure utilizes Haar filters, and longer filters such as 5/3 is also utilized extensively. In this paper, an improved db-2 based MCTF is proposed. The lowpass frames obtained by this db2-based MCTF whose PSNR is higher than haar-based MCTF keep more approximate information of original frames.Efficient EEG compression using JPEG2000 with coefficient thresholding
http://dl-live.theiet.org/content/conferences/10.1049/cp.2010.0488
This paper outlines a scheme for compressing EEG signals based on the JPEG2000 image compression algorithm. Such a scheme could be used to compress signals in an ambulatory system, where low-power operation is important to conserve battery life; therefore, a high compression ratio is desirable to reduce the amount of data that needs to be transmitted. The JPEG2000 specification makes use of the wavelet transform, which can be efficiently implemented in embedded systems. In this research, the JPEG2000 standard was broken down to its core components and adapted for use on EEG signals with additional compression steps added. Variations on the compression architecture were tested to maximize compression ratio (CR) while minimizing reconstructed percentage root-mean-squared difference (PRD) and power requirements. Tests indicate that the algorithm performs well in efficiently compressing EEG data, without significant loss in signal fidelity.Embedding data and sharing original image in two stego images using Sudoku
http://dl-live.theiet.org/content/conferences/10.1049/cp.2010.0555
Secret information can be protected by using information hiding techniques. In this paper, we propose a novel reversible information hiding scheme by using Sudoku. The proposed scheme embeds two secret digits in the base-9 numeral system into a cover pixel pair by distributing them into two stego pixel pairs at a time. In comparison with the related work, the experimental results show that our proposed scheme achieves higher embedding capacity with acceptable lower visual quality of stego images. In addition, our proposed scheme is a reversible information hiding scheme in which the original cover image can be completely recovered after secret data has been extracted. Furthermore, the proposed scheme obtains the security purpose by sharing secret data into two stego images and using different Sudoku's solutions for different secret data transmissions.A new non-expansion visual cryptography scheme with high quality of recovered image
http://dl-live.theiet.org/content/conferences/10.1049/cp.2010.0571
In the traditional visual cryptography scheme, a secret pixel will be encoded into a block, causing the size of recovered image is larger than the original one. Thus, later studies attempt to improve these shortcomings, distortion of the recover image and a higher transmission cost. This paper proposes a visual secret sharing (VSS) scheme without expansion, and gets a better recovered result than other schemes due to the consideration of black pixels' distribution.Information hiding using stochastic diffusion for the covert transmission of encrypted images
http://dl-live.theiet.org/content/conferences/10.1049/cp.2010.0480
A principal weakness of all encryption systems is that the output data can be 'seen' to be encrypted. In other words, encrypted data provides a 'flag' on the potential value of the information that has been encrypted. In this paper, we provide a novel approach to 'hiding' encrypted data in a digital image. We consider an approach in which a plaintext image is encrypted with a cipher using the processes of 'stochastic diffusion' and the output quantized into a 1-bit array generating a binary image ciphertext. This output is then 'embedded' in a host image which is undertaken either in the lowest 1-bit layer or multiple 1-bit layers. Decryption is accomplished by extracting the binary image from the host image and correlating the result with the original cipher. The approach has a variety of applications including: (i) covert transmission of encrypted images; (ii) authentication and self-authentication of e-documents that are assumed to be communicated over the Internet and are thereby vulnerable to attack (e.g. modification, editing, counterfeiting etc.). The paper includes an address from which interested readers can download a prototype system called StegoCrypt developed using the algorithms presented.Distortion optimization based on power allocation for wireless video sensors
http://dl-live.theiet.org/content/conferences/10.1049/cp.2010.0607
Wireless video sensor networks (WVSNs) feature the characteristics of easy deployment and low maintenance cost and therefore are suitable for a wide range of important applications, including remote surveillance, health care delivery and traffic control systems. Compared to traditional communication systems, Sensor nodes in WVSN operate under resource constrains such as power supply and transmission bandwidth. The main object of this paper is to study the resource allocation of a wireless sensor node and improve the system performance, especial the video distortion. More specifically, by taking into account the relations between separated modules on a sensor node, we build a comprehensive power-rate-distortion (PRD) framework for WVSN optimization. Based on this framework, we address the problem of power allocation between video encoder module and wireless transmission module on the node to achieve the optimal reconstructed video quality under power and rate constraints.Estimation of fading attack on high payload spread spectrum watermarking with variable embedding rate using genetic algorithms
http://dl-live.theiet.org/content/conferences/10.1049/ic.2009.0243
Spread Spectrum (SS) watermarking is the most popular one and robust to several attacks, but the correlation receiver structure widely used for SS watermark detection is not effective in the presence of fading like attack. Moreover, watermark detection performance is greatly affected in high payload SS system under fading attack. Recently, a new model of high payload SS watermarking with minimum mean square error combining (MMSEC) decoder structure is proposed that has shown improved detection performance through multistage interference cancelation. We modify this SS watermarking for variable embedding rate so that each host signal point allows different data hiding capacity. This work further shows that the fading attack can be estimated and similar order of detection improvement can be achieved without interference cancelation or with interference cancelation at single stage. Genetic Algorithms (GAs) is used to estimate fading attack optimally for high payload SS watermark systems and this yields low bit error rate (BER) value. Simulation results show that gap in BER performance due to the actual value of fading attack and due to its estimated value is very small and this performance can be achieved with much lower computation cost. (6 pages)Adaptive watermarking scheme based on ICA and RDWT
http://dl-live.theiet.org/content/conferences/10.1049/ic.2009.0239
This paper proposes a new approach to watermarking multimedia products based on the combination of redundant discrete wavelet transform and independent component analysis. The original image is decomposed by RDWT, and watermark is embedded in to LL sub-band frequency according mixing model of the ICA, after that for enhancing the robustness of the watermark, the perceptual model is applied via stochastic approach for watermark adapting. This is based on computation of a noise visibility function (NVF) which has local image properties so the strength of watermarking is controllable. Principal component analysis (PCA) whitening process and FastICA techniques are introduced to ensure a blind watermark extraction without requiring the original image. Experimental results show the proposed technique is robust under compression attacks. (4 pages)Detecting double compressed JPEG images
http://dl-live.theiet.org/content/conferences/10.1049/ic.2009.0240
Verifying the integrity of digital images and detecting the traces of tampering without using any protecting pre-extracted or pre-embedded information has an important role in image forensics and crime detection. When altering a JPEG image, typically it is loaded into a photo-editing software and after manipulations are carried out, the image is re-saved. This operation, typically, brings into the image specific artifacts. In this paper we focus on these artifacts and propose an automatic method capable of detecting them. (6 pages)Image error concealment based on data hiding using M-ary QIM
http://dl-live.theiet.org/content/conferences/10.1049/ic.2009.0247
Methods like edge directed interpolation and projection onto convex sets (POCS) that are widely used for image error concealment to produce better image quality are complex in nature and also time consuming. So those methods are not suitable for real time error concealment where the decoder may not have sufficient computation power or done in online. In this paper, we propose a data hiding scheme for error concealment of digital image. Edge direction information of a block is extracted in the encoder and is embedded imperceptibly into the host media using quantization index modulation (QIM), thus reduces work load of the decoder. The system performance in term of fidelity and computational load is improved using M-ary data modulation based on nearorthogonal QIM. The decoder extracts the embedded features (edge information) and those features are then used for recovery of lost data. Experimental results duly support the effectiveness of the proposed scheme. (6 pages)High-profile forensic analysis of images
http://dl-live.theiet.org/content/conferences/10.1049/ic.2009.0246
Amidst many different forms of image manipulation, how to convince a jury of a tampering? Is traditional expert opinions enough? In this paper, using a high-profile Brazilian case as a guideline, we explain how we can take advantage of important statistical methodologies and state-of-the-art techniques to verify evidences of digital tampering, beyond reasonable doubt. (6 pages)Has F5 really been broken?
http://dl-live.theiet.org/content/conferences/10.1049/ic.2009.0245
The publicly-available F5 software (F5Software) implementation takes a possibly compressed cover image, decompresses it if necessary, and embeds the hidden message during a second compression process. This procedure introduces a risk that the stego image goes through 'double compression'. While this is not a problem from the embedding and extraction point of view, any steganalysis process trained on such a scheme will potentially detect artifacts caused either by the embedding process or the second compression process. In this paper we review published steganalysis techniques on F5. By re-implementing an isolated F5 embedding algorithm excluding the decompression and recompression process (F5Py), we show that published steganalysis techniques are unable to defeat F5 when its ideal operational condition is not violated. In other words, published techniques most likely detected the compression artifacts rather than the embedding process when the message size is not exceeding the optimum F5 capacity. This is an important fact that has been ignored before. Furthermore, we look for the optimum embedding rate for F5 in order for it to take advantage of matrix encoding for better embedding efficiency. From here we found that the low embedding rate considered for F5 in the previous works are actually relatively high for it. This is also important since bigger message size might degrade F5 to F4. In addition, we also verify that, as expected, steganalysis performance depends on the message size. (5 pages)