Creation of laser-induced images within transparent materials is discussed. The special attention is attended to creating 2D and 3D laser-induced portraits. Method producing 3D laser-induced portrait by using two 2D portraits is examined.

Coherent stereo pairs from cross-track synthetic aperture radar (SAR) collects allow fully automated correlation matching using magnitude and phase data. Yet, automated feature matching (correspondence) becomes more difficult when imaging rugged terrain utilizing large stereo crossing angle geometries because high-relief features can undergo significant spatial distortions. These distortions sometimes cause traditional, shift-only correlation matching to fail. This paper presents a possible solution addressing this difficulty. Changing the complex correlation maximization search from shift-only to shift-and-scaling using the downhill simplex method results in higher correlation. This is shown on eight coherent spotlight-mode cross-track stereo pairs with stereo crossing angles averaging 93.7°. collected over terrain with slopes greater than 20°. The resulting digital elevation maps (DEMs) are compared to ground truth. Using the shift-scaling correlation approach to calculate disparity, height errors decrease and the number of reliable DEM posts increase.

Vision-based highway monitoring systems play an important role in transportation management and services owing to their powerful ability to extract a variety of information. Detection accuracy of vision-based systems is however sensitive to environmental factors such as lighting, shadow and weather conditions, and it is still a challenging problem to maintain detection robustness at all time. In this research, we present a novel method to enhance detection and tracking accuracy at the nighttime based on rear-view monitoring. In the meanwhile, a method is proposed to improve the background detection and extraction, which usually serves as the first step to moving object region detection. Finally, the effectiveness of the rear-view technique will be analyzed. We compare the tracking accuracy between the front-view and the rear-view techniques, and show that the proposed system can achieve higher detection accuracy at nighttime.

Traditional techniques of microbial density estimation involve analysis of microbes from still images of water samples. However, microorganisms are non-rigid objects that swim in polluted water and are surrounded by static clutter and debris. As a result, the detection and classification of microorganisms based on their shape, size, and orientation becomes a very difficult task. In view of above, a microbial population density estimation technique based on analysis of video images of moving microbes is of considerable interest. Many of these microorganisms have unique motion characteristics and this paper proposes a technique for micro organisms classification based on the motion characteristics. Motion detection is carried out on preprocessed image sequences obtained from a microscope mounted CCD camera. A block matching technique in the frequency domain using the phase shift property of the Discrete Hartley Transform (DHT), is used to estimate the position of the microorganism in the current frame. Tracking of the various microorganisms is performed using the Interacting Motion Models (IMM). The position estimates are used as an input to the IMM tracker. The motion characteristics of the various types of micro organisms are modeled by three models namely: Zero velocity motion model is used to identify slow moving organisms, the constant velocity model defines organisms moving in near straight line trajectories, the third model is the coordinated turn model, a high maneuvering model which is used to characterize spiral and zigzag motion. Multiple microorganisms can be tracked using this technique, and is more reliable in recognition of the track characteristics than using a bank of 'non-interacting' single model-based filters. The track characteristic and the mode probabilities are unique property of a particular organism. The track data obtained from the IMM and the mixing probabilities of the various models used in the track, are used as a feature set. Principal Component Analysis (PCA) is used for feature extraction. Classification is to be carried out using the Hidden Markov Models (HMM). The performance of the proposed technique is evaluated using simulated image sequences and actual images obtained from the field.

We present a new attitude estimation algorithm for a freely moving rigid body using an imaging sensor, two accelerometers and three gyros which are mounted in the body. The proposed attitude estimation algorithm, which is based on the extended Kalman filter (EKF), uses two measurements; the reference direction-vector derived from the image and the local vecrtical vector obatined from the two accelerometers. To obtain the reference direction-vector from the imaging sensor, we track a preselected feature block in successive image frames using an image-based region tracking method which does not require a time-consuming image-registration process. Our block-matching algorithm is based on the one in MPEG-2. Using the two direction vector measurements, we obtain a filtered estimate of the Euler angles of the rigid body. Between two successive measurements we use the rate-gyros to propagate (or to obtain the predicted estimate of) the Euler angles. One of the possible applications of the proposed algorithm is for the automatic targeting capability that would be required in a next-generation military rifle. Our algorithm has been implemented in hardware, and shown to be functioning properly.

The goal of this work is to provide bomb squad units with innovative algorithms for the automatic detection and highlight of blasting caps and other components within x-ray imagery. In this paper, an integrated image processing algorithm, referred to as X-ray Interpreter (XI) is presented that autonomously analyzes data collected by an x-ray imager. The algorithm detects and recognizes a blasting cap of reference in the image, and highlights its location whenever present. This process will assist the operator to focus more on regions within the regions within the image that are highlighted by the algorithm. Examples of applying the algorithm to real data are shown along with performance measure curves for detection and false alarm probabilities.

In this paper, we investigate the performance of an objective video quality assessment method using the wavelet transform for a large data set. The objective video quality assessment utilizes the wavelet transform, which is applied to each frame of source and processed videos in order to compute spatial frequency components. Then, the difference (squared error) of the wavelet coefficients in each subband is computed and summed. By repeating this procedure to the entire frames of a video, a sequence of difference vectors and the average vector are obtained. Each component of the average vector represents a difference in a certain spatial frequency. In order to take into account the temporal frequencies, a modified 3-D wavelet transform can be applied. Although this evaluation method provides a good performance for training data, its performance for new test videos remains to be seen due to a large number of parameters. In this paper, we apply the method to a large video data set and analyze the performance.

Tuberculosis is a serious illness which control is mainly based on presumptive diagnosis. A technique commonly used consists of analyzing sputum images for detecting bacilli. However, the analysis of sputum is quite expensive, time consuming and requires highly trained personnel to avoid high errors. Image processing techniques provide a good tool for improving the manual screening of samples. In this paper we present a new bacilli detection technique with the aim to attain a high specificity rate and therefore for reducing the time required to analyze such sputum samples. This technique is based on the neuristic acknowlege extracted from the bacilli shape contour. It uses also the color information for image segmentation and finally a classification tree is used to categorize if a sample is positive or negative.

Robust adaptive correlations based on rank order operations such as alpha-trimmed sum and median for illumination-invariant pattern recognition are proposed. Several properties of the correlations are investigated. Their performance for detection of noisy objects is compared to the conventional linear correlation in terms of noise robustness and discrimination capability. Computer simulation results for a test image corrupted by mixed additive and impulsive noise are provided and discussed.

Combining data from different sensors of the same scene acquired at different times to create a hybrid is a common task in remote sensing. The first step of this task is to register these same-scene images (geometric integration). The accuracy of this step is important to create a valuable final hybrid image. The second step is radiometric integration (data fusion), which enriches the information of individual pixels in the image. This paper addresses the first task, i.e. geometric integration, and introduces a new method for automatically registering two dissimilar images, such as a radar image and an optical image, with high accuracy. Pre-registration of the two images is required to within a specified tolerance, which in our examples is up to 15 pixels at the higher resolution image and may be achieved by, for example, visually-located control points. The proposed approach then uses large-scale edge gradient contours in a process that automatically locates candidate control points on the contours. The points are selected using a cost function that involves the degree of match between all possible pairs of points. Numerous control points (around 50 pairs are typical) are found from matched pairs of gradient contours and used in a global, rubber sheet polynomial warp to refine the registration. This approach is applied to register a Synthetic Aperture Radar (SAR) image (ERS2, 12.5m pixels) and a Thematic Mapper (TM) image (Landsat5, 28.5m pixels) automatically. An example is shown and discussed in terms of residual registration error and processing efficiency.

In this paper we present a distributed processing system that will be used for manual and/or automated change detection using data from databases and from online sensors. The automated change detection algorithm described herein is based on a method developed by Armenakis et al. This technique is applied on two level image classification. Its extension to multiple level classification and change detection is also being discussed. The paper presents two other change detection methodologies that are based on the Principal Component Analysis and wavelet techniques. Finally, it discusses the effect of matched filters for improving the change detection performance. Experimental results are provided using RADARSAT images which have been registered with the automated registration algorithm of AUG Signals that is currently available under the distributed procesing system www.signalfusion.com.

This paper presents a stereo matching algorithm which combines a dense B-spline representation and an adaptive regularization technique to produce a detailed and stable depth field. We demonstrate that splines may fail in representing some regions in a disparity map due to occlusions. To address this problem, we propose to perform spline representation in object space and directly carry out surface reconstruction from stereo images. The effectiveness of this algorithm has been demonstrated by experimental results on real images.

In this paper, a new stereo object tracking system using the disparity motion vector(DMV) is proposed. Here, the DMV is defined as a disparity difference between two time-sequential disparity maps of T-1 and T frames and it can be sequentially estimated from the disparity maps which are extracted from the input stereo sequence. Here, the disparity maps are obtained by using the feature-based matching algorithm, in which the block size and the search range for the feature-based matching are given by N_x×N_y=1×1 and S_x=±32, respectively. And then, the DMV can be estimated by calculating the motion difference between two consecutive disparity maps. Basically, the DMV has a relatively large change of disparity values in the target region because of the target’s movement, whereas it has very low difference values in the background region; there are almost no changes by comparing with the target region. As a result, the DMV can provide us with the motional information of a moving target by showing a large disparity difference in the target area. That is, the dynamic relationship between these disparity vectors of T-1 and T frames seems to be very similar to that between the motion vectors of T-1 and T frames in the sequence of the conventional 2D video images. Accordingly, the target area and its location coordinates can be detected by using these DMV maps. Basing on these locational data of a moving target, the pan/tilt embedded in the stereo camera system can be controlled and as a result, real-time stereo tracking of a moving target can be achieved. From some experiments with 9 frames of the stereo sequence having 256×256 pixels, it is shown that the proposed DMV-based stereo object tracking system can track the moving target with a relatively low error ratio of about 3.02% on average. This good experimental result finally suggests a possibility of implementing the DMV-based stereo object tracking system.

Background subtraction is widely used for the detection of objects moving against a background in video. Moving objects are detected by comparing the current image with the extracted background image (BI). The BI is constructed using a single or several frames without moving foreground object in the scene. The pixel in BI is updated by the current pixel value if this pixel is determined to be part of the background during the subtraction process. The drawback of this approach is the requirement of the establishment of a background image prior to the detection; otherwise any object that appears in the first frame is detected as “moving object” through the whole sequence. An even more serious problem occurs when there is a sudden change in the background, such as a light being turned on or off, or a newly arrived “still” object. As long as the pixel value change is larger than the threshold, the “still” object after the sudden change will not be included in the background image and hence it will appear as a moving object in the following frames. To avoid these problems, we propose an approach in which a second updated background image, BI₂, is stored. BI₂ is initially constructed from the first frame detected and then updated through the detection processes with criteria different to that used in updating BI. The pixels in BI2 are updated if they have been determined as background pixels by comparing the difference between the current and previous frames. By using this method, the “still” objects are not falsely detected as moving objects. After a few frames, the “still” objects are updated into the background image BI₂. BI₂ is then incorporated into the background image BI. Moving objects are then subtracted from the modified background image BI and the “still” objects are eliminated.

Wide area symbol recognition is a task that plagues many autonomous vehicles. A process is needed first to recognize if the symbol is present, and if so where it is. Once the symbol's position is detected it must be analyzed and recognized. In this scenario we have a submersible attempting to locate man made objects on the bottom of a large water basin. These man made objects have bar codes on them that need to be read and the position of the code needs to be recorded relative to where it is in the entire pond. A two step process has been developed to allow the position recognition within a frame to be dealt with on a separate DSP associated with one of three total cameras. The object recognition is then dealt with on a high speed computer aboard the vehicle to read the proper code. The reading is done using a statistics based approach that assumes a noisy, but contrasting background. This approach has proven to be effective in environments in which the background has very little ordered noise, such as the bottom of lakes and ponds, but requires very high clarity in order to capture a suitable image.

We present an effective method for texture segmentation and analysis using a local spectral method. The method combines the advantages of a high spectral resolution of a joint representation given by the Pseudo-Wigner distribution with an effective adaptive principal component analysis. Performance of the method is evaluated using fabric samples with defects, medical images, and crack detection in metallic surfaces. The examples demonstrate the discrimination power of the present method for detecting even very subtle changes in the homogeneity of textures.

In the last two decades, many papers have been published, proposing a variety of methods for multi-frame resolution enhancement. These methods, which have a wide range of complexity, memory and time requirements, are usually very sensitive to their assumed model of data and noise, often limiting their utility. Different implementations of the non-iterative Shift and Add concept have been proposed as very fast and effective super-resolution algorithms. The paper of Elad & Hel-Or 2001 provided an adequate mathematical justification for the Shift and Add method for the simple case of an additive Gaussian noise model. In this paper we prove that additive Gaussian distribution is not a proper model for super-resolution noise. Specifically, we show that L_p norm minimization (1≤p≤2) results in a pixelwise weighted mean algorithm which requires the least possible amount of computation time and memory and produces a maximum likelihood solution. We also justify the use of a robust prior information term based on bilateral filter idea. Finally, for the underdetermined case, where the number of non-redundant low-resolution frames are less than square of the resolution enhancement factor, we propose a method for detection and removal of outlier pixels. Our experiments using commercialdigital cameras show that our proposed super-resolution method provides significant improvements in both accuracy and efficiency.

Increasingly demanding military requirements and rapid technological advances are producing reconnaissance sensors with greater spatial, spectral and temporal resolution. This, with the benefits to be gained from deploying multiple sensors co-operatively, is resulting in a so-called data deluge, where recording systems, data-links, and exploitation systems struggle to cope with the required imagery throughput. This paper focuses on the exploitation stage and, in particular, the provision of cueing aids for Imagery Analysts (IAs), who need to integrate a variety of sources in order to gain situational awareness. These sources may include multi-source imagery and intelligence feeds, various types of mapping and collateral data, as well the need for the IAs to add their own expertise in military doctrine etc. This integration task is becoming increasingly difficult as the volume and diversity of the input increases. The first stage in many exploitation tasks is that of image registration. It facilitates change detection and many avenues of multi-source exploitation. Progress is reported on the automating this task, on its current performance characteristics, its integration into a potentially operational system, and hence on its expected utility. We also report on the development of an evolutionary architecture, 'ICARUS' in which feature detectors (or cuers) are constructed incrementally using a genetic algorithm that evolves simple sub-structures before combining, and further evolving them, to form more comprehensive and robust detectors. This approach is shown to help overcome the complexity limit that prevents many machine-learning algorithms from scaling up to the real world.

The JPEG 2000 image compression algorithm and associated file formats create many new opportunities for sharing digital images. Through a highly scalable storage format, a JPEG 2000 image can be accessed at multiple resolutions and quality levels without first decompressing the entire image file and post-processing the data. The JPEG 2000 Internet Protocol (JPIP) provides direct access to this scalability by allowing a client and server to negotiate for the delivery of only portions of the image file, as required by the client. In addition to progressively accessing the coded image data, JPIP allows for “progressive” access to the metadata contained in the file. Through the use of placeholders, the file format header and metadata can be progressively delivered to the client while still maintaining a link to the original file structure. In addition, JPIP allows for XML documents that have been embedded from the file to be searched using XPath. This paper discusses how these two technologies can be used to flexibly access the metadata in a JPEG 2000 file.

The development of the JPEG 2000 standard was quite contentious due to the widely varying goals of the participants. The result was that JPEG 2000 is the most flexible image compression standard to date. However, in order to complete the standard within the 2000 calendar year any definition of what a decoder must do was removed from the initial standard. JPEG 2000 Part 4 is the standard which defines conformance of a decoder (and to a lessor extent an encoder) with JPEG 2000. This paper describes how decisions were made about compliance with JPEG 2000 and the methods used for testing.

One of the key properties of the JPEG2000 standard is that it is possible to parse a JPEG2000 bit-stream to extract a lower resolution and/or quality image without having to perform dequantization and requantization. This property is especially useful given the variety of devices with vastly differing bandwidth and display capabilities that can now access the Internet. It is anticipated that a high-resolution JPEG2000-compressed image stored at an image server will be accessed by a variety of clients with differing needs for resolution and image quality. To satisfy the needs of these heterogeneous clients, it is essential that the server have the ability to transcode a JPEG2000 image in an efficient manner with very little loss in image quality. In this paper, we present a number of methods for transcoding a JPEG2000 image and evaluate each with respect to computational complexity and the quality of the transcoded image.

This paper investigates the use of wavelets to automatically register remotely sensed images. The proposed algorithm is based on the Laplacian of Gaussian (LoG) filter to automatically extract ground control points and the discrete wavelet transform (DWT) for multiresolution analysis. The structural properties of the wavelet coefficients can be exploited in a unique fashion to reduce the search space for the control points. The inherent multiresolution processing of the image data provides an efficient method for registering large image data sets because the full-size does not require processing.

JPEG 2000 is the emerging image compression standard. Some of the more commonly used features and benefits of using JPEG 2000 over JPEG are; superior image quality at low bit rates, image tiling, lossless and lossy compression utilizing the same core algorithm, and progression order control (such as quality layer progression). In this paper, we discuss some of the more advanced techniques in utilizing the JPEG 2000 standard, such as; using rate distortion slope values to compress sets of images to relative image quality levels, and using precinct partition dimension specifications as an alternative to using image tiling for the processing of very large images. Examples will be given and results will be provided.

The region of interest (ROI) coding feature of JPEG 2000 image compression standard is extended to multispectral imagery. This is accomplished by enabling ROI capability of JPEG 2000 module in the previously developed Karhunen-Loeve/JPEG 2000 compression of multispectral images. Preliminary results, based on subjective, statistical, and machine-based exploitation measures, show significant improvement in the compression performance. Depending on the ROI/background relative size and the desired quality differential, the improvement in the classification accuracy can increase by as much as one hundred percent without an increase in the bandwidth.

JPEG 2000 is the emerging image compression standard. This International Standard defines a normative but optional file format for storing compound images using the JPEG 2000 file format family architecture. A compound image is an image that may contain scanned images, synthetic images or both, and that preferably requires a mix of continuous tone and bi-level compression methods. Besides defining a binary container for a mix of continuous-tone and bi-level images, this format defines a composition model that describes how the multiple images are combined to generate a compound image. This composition model is based on the multi-layer Mixed Raster Content (MRC) imaging model. A key feature of JPM is its support of fragmented JPEG 2000 codestreams to enable progressive and interactive rendering in web applications. In this paper, we describe the design and implementation of JPM Reader/Writer and a prototype compound image file interactive viewer, in the context of browser plug-ins, and Web Service applications. Examples will be given and results will be provided.

JPEG2000 is the new ISO/IEC image compression standard. It is a full coding system targeted for various imaging applications. Besides offering the state-of-the-art in still image compression, it provides new features such as scalability in quality and in resolution, random access and region of interest (ROI) coding. Motion JPEG2000 is an inherited video compression standard based on intra-farme coding using JPEG2000. JPIP (the JPEG2000 Interactive Protocol), is a developing protocol for the access and transmission of JPEG2000 coded data and related metadata in a networked environment. In this paper, we present various applications of JPEG2000, Motion JPEG2000 and JPIP, geared specially towards the wireless mobile environment. We present an Image Surfing system for surfing JPEG2000 images on mobile terminals over a wireless network. We also present a scheme for tracking and coding Regions-Of-Interest (ROI) over a Motion JPEG2000 sequence. Finally, we present a Partial Coding scheme for use in Motion JPEG2000 sequences that gives coding gains for certain types of video sequences.

The image compression standard JPEG2000 brings not only powerful compression performance but also new functionality unavailable in previous standards (such as region of interest, scalability and random access to image data, through flexible code stream description of the image). ISO/IEC JTC1/SC29/WG1, which is the ISO Committee working group for JPEG2000 standardization is currently defining additional parts to the standard that will allow extended functionalities. One of these extensions is Part 8 JPSEC - JPEG2000 security, which deals with the protection and access control of JPEG2000 code-stream. This paper reports the JPSEC activities detailing with the three core experiments which are in progress to supply the JPEG2000 ISO Committee, with the appropriate protection technology. These core experiments are focusing on the protection of the code-stream itself and on the overall security infrastructure that is needed to manage the access rights of users and applications to that protected code-stream. Regarding the encryption/scrambling process, this one deals with the JPEG2000 code stream in such a way that only the packets, which contain image data information are encrypted. All the other code-stream data will be in clear mode. This paper will also advance details of one of the JPSEC proposed solutions for the security infrastructure - OpenSDRM (Open and Secure Digital Rights Management), which provides security and rights management from the content provider to the content final user. A use case where this security infrastructure was successfully used will also be provided.

Embedded image processing systems have to face heavier and heavier constraints in order to cope with the growing complexity of the algorithm and the increasing flexibility required by applications, while fulfilling more and more demanding implementation constraints. With a variety of target application profiles that include digital photography and remote sensing, the JPEG2000 standard is a typical example where complex and scalable techniques have to be implemented into highly integrated platforms. While the electronic system design community has pushed design-by-reuse as a key to manage complexity, providing a reusable hardware arhtiecture for JPEG2000 while preserving the high flexibility required by the wide application space is a major challenge. In this paper, we propose to address this issue by relying on a new class of synthesis tools: high-level synthesis (HLS) tools. HLS allows to specify hardware at a high abstraction level, where a variety of functional and architectural properties can be made customizable, and provides an automatic, constraint-driven architectural refinement flow that allows to generate a detailed register-transfer-level architecture from a behavioral (algorithmic-like) description of a component's behavior. Using a commercial HLS tool, we were able to generate a variety of JPEG2000-compliant discrete wavelet transform architectures, with varying hardware complexity and computation speed, from a single behavioral-level VHDL specification.

Recently, the JPEG2000 committee (ISO/IEC JTC1/SC29/WG1) decided to start up a new standardization activity to support the encoding of volumetric and floating-point data sets: Part 10 - Coding Volumetric and Floating-point Data (JP3D). This future standard will support functionalities like resolution and quality scalability and region-of-interest coding, while exploiting the entropy in the additional third dimension to improve the rate-distortion performance. In this paper, we give an overview of the markets and application areas targeted by JP3D, the imposed requirements and the considered algorithms with a specific focus on the realization of the region-of-interest functionality.

While the recent JPEG2000 standard only specifies the bitstream and file formats to ensure interoperability, it leaves the actual implementation up to the designer. Like many DSP applications, there are a number of implementation platform options for the designer. This paper gives a complexity analysis of an implementation of a JPEG2000 encoder using a hardware/software co-design methodology on a Xilinx Virtex-II(TM) platform FPGA. Central to the performance of the encoder is a high-throughput tier-1 entropy coder. This paper will describe the encoder design targeted for video surveillance applications, and will compare and contrast with two other implementation options.

JPEG2000 offers a new coding of images with a hierarchical data structure from which a user can pick up the only necessary codestream for the generation of representation matched to his needs. Therefore, a unitary and multipurpose image exchange system can be made from combining the new JPEG2000 technology and classical mailer tools. This paper proposes such a flexible access method. The proposed server consists of two POP3 servers, a SMTP server, the image list database and the image database. The POP3 server performs user authentication and provides the image list. The SMTP server receives the client's request and transmits the appropriate image. First the user connects to the 1st POP3 server with ID and password, then receives the available image list as e-mails. One mail is sent for each available representation of an image, i.e. each JPEG2000 progression order and image format. The hash value of the codestream and the JPEG2000 progression order values are included in the Message-ID of each mail header. Information, such as the name of the image, size, quality of image, is written in the text. Then, the user orders an image by replying to the corresponding mail of the list. When the SMTP server receives the client's e-mail, it prepares the desired image, and provides a mail with that image to the client via the second POP3 server. The proposed system is validated with different platform mailer tools.

This paper introduces the applications of image processing and JPEG2000 in pathology. Our study aims to provide pathologists valuable assistance on examining biopsy samples of prostate and support their decision. The digital color microscopic image is processed only within the regions of interest instead of overall processing. In this way, some diagnostic information is enhanced to provide better visual effect. JPEG2000 is used for the storage and interactive transmission of the large pathological images. Our simulation results show that the use of JPEG2000 can significantly save storage space without compromising the diagnostic value of the image.

Data hiding in JPEG-2000 compressed images is investigated in this research. The challenges of covert communication in this state-of-the-art image codec are analyzed and a steganographic scheme is then proposed to embed high-volume data into the JPEG-2000 bit-stream secretly and reliably. A special mode of JPEG-2000 is employed, and its usage and functions are explained and justified. Experimental results are given to demonstrate the performance of the proposed algorithm.

In this paper the transmission of JPEG2000 and Motion JPEG2000 codestreams in WLAN 802.11 environment is analized. The issues related to the transmission of JPEG2000, using non reliable protocols as UDP-RTP, are investigated and a proper protection scheme for dealing with such an environment is presented, along with the obtained performance with different systems parameters. The proposed technique addresses a wide range of multimedia applications such as wireless PC to Digital Projector multimedia presentations, point to multipoint digital slide projection, wireless video-surveillance systems.

This paper addresses the problem of quality assessment dedicated to two important applications : image compression and watermarking. This topic is nowadays of a great interest because of the limitations of the mathematical criteria used formerly for quality assessment. The main aspect of this paper is the use of psychophysical experiences in order to take into account the capacities of the Human Visual System. Two campaigns have been taken for assess quality for both compression and watermarking. The main conclusion of this work is that the metrics used to assess quality such as the PSNR are very far from the human judgment and consequently from the real assessment.

Assessing and comparing the performance of watermarking algorithms is difficult. The visibility of the watermark is an important aspect in this process. In this paper, we propose two metrics for evaluating the visual impact of video watermarks. Based on several different watermarking algorithms and video sequences, we identify the most prominent impairments as spatial noise and temporal flicker. We design the corresponding measurement algorithms and corroborate their performance through subjective experiments.

Over the past decade, very fruitful efforts have converged to offer tools devoted to the processing of meshes. Spectral decomposition of mesh geometry has first found its applications in both filtering and mesh partitioning. It has been lately extended to address transmission and watermarking issues. Such a decomposition gives rise to pseudo-frequential information of the geometry defined over the mesh connectivity. For large meshes a piecewise decomposition has to be applied in order to restrict the complexity of the transform. In this paper, we propose a lapped spectral representation for compression and watermarking purposes.

Watermarking sofwares are difficult to evaluate because their desired features have to be evaluated in a multidimensional space. Furthermore, the required characteristics are strongly dependent on the envisaged scenario in which the watermarking will be evaluated. While several benchmarking systems have been proposed to include attacks, perceptual and statistical evaluations, none of them constitute an established reference. Due to the difficulty of this benchmarking issue, we propose to set a web based open-source suite of tools which would allow the scientific community around watermarking research to achieve fair and reproducible benchmarking tests. This paper describes the required basic architecture. A benchmarking session is parameterized with several options relevant to media, embedding, decoding, attacks, etc. The session is divided into tests (which may encompass several runs), and the results are collected and submitted to set multidimensional curves.

The Joint Photographic Experts Group (JPEG) has recently rolled out a new still image coding standard called JPEG 2000. This standard integrates an efficient image compression scheme along with functionalities required by multimedia applications, such as progressiveness up to lossless coding, region of interest coding, and error resiliency. Security is a concern in many applications, and therefore a highly desired functionality. For this reason, JPEG recently initiated an activity known as secure JPEG 2000 (JPSEC) in order to provide a standardized framework for secure imaging. This paper presents some insights on the current status of the JPSEC activities. We also provide examples of how to combine security solutions with JPEG 2000 compression. More specifically, tools for JPEG 2000 compressed image integrity, access control, and copyright protection are presented. They can be either applied to a JPEG 2000 codestream or directly integrated into the coding/decoding operations. In all cases, they result in a fully compliant JPEG 2000 image.

In response to a requirement from the United States Postal Inspection Service, the Technical Support Working Group tasked The Johns Hopkins University Applied Physics Laboratory (JHU/APL) to develop a technique tha will ensure the authenticity, or integrity, of digital video (DV). Verifiable integrity is needed if DV evidence is to withstand a challenge to its admissibility in court on the grounds that it can be easily edited. Specifically, the verification technique must detect additions, deletions, or modifications to DV and satisfy the two-part criteria pertaining to scientific evidence as articulated in Daubert et al. v. Merrell Dow Pharmaceuticals Inc., 43 F3d (9th Circuit, 1995). JHU/APL has developed a prototype digital video authenticator (DVA) that generates digital signatures based on public key cryptography at the frame level of the DV. Signature generation and recording is accomplished at the same time as DV is recorded by the camcorder. Throughput supports the consumer-grade camcorder data rate of 25 Mbps. The DVA software is implemented on a commercial laptop computer, which is connected to a commercial digital camcorder via the IEEE-1394 serial interface. A security token provides agent identification and the interface to the public key infrastructure (PKI) that is needed for management of the public keys central to DV integrity verification.

H.264/MPEG-4 AVC is the latest coding standard jointly developed by the Video Coding Experts Group (VCEG) of ITU-T and Moving Picture Experts Group (MPEG) of ISO/IEC. It uses state of the art coding tools and provides enhanced coding efficiency for a wide range of applications including video telephony, video conferencing, TV, storage (DVD and/or hard disk based), streaming video, digital video creation, digital cinema and others. In this paper an overview of this standard is provided. Some comparisons with the existing standards, MPEG-2 and MPEG-4 Part 2, are also provided.

Joint Video Team (JVT) was established to standardize next video coding technology. ITU-T H.26L (TML8) was adopted as the start point of the standard, and Joint Model (JM) was released. High quality video, not only for professional equipments but also for consumer applications, is very important target for JVT codec. However, H.26L was tested relatively lower bit rate. It is found that there are several problems due to quantization in order to support high quality video. In this paper, two extensions of quantization to support high quality video, which are frequency weighting matrix and extension of quantization table, are proposed. The frequency weighting matrix adds flexibility to the transform and quantization process by providing substantial coding efficiency without sacrificing the visual quality. It is possible to change quantization characteristic for each frequency depending on the sensitivity of human visual system. Encoder can compress video more efficiently. By extending the quantization table, encoder can use smaller and larger q_scale. In order to confirm the advantage of the proposal, simulations were performed to evaluate both PSNR and subjective quality. It was verified that proposed method is able to reduce bit rate keeping the same visual quality.

In this paper, we introduce a new motion vector prediction method that could be used within multiple picture reference codecs, such as the H.264 (MPEG-4 AVC) video coding standard. Our method considers for each candidate motion vector the temporal distance of its corresponding reference picture compared to the current one for the generation of the predictor motion vector. This allows for more accurate motion vector prediction, and better exploitation of the temporal correlation that may exist within a video sequence. Furthermore, we also introduce a modification to the SKIP motion vector macroblock mode, according to which not only the motion vectors but also the reference indices are adaptively generated. Simulation results suggest that our proposed methods, combined with an improved Rate Distortion optimization strategy, if implemented within the existing H.264 codec, can allow for a considerable performance improvement of up to 8.6% bitrate reduction compared to the current H.264 standard.

The DVD is emerging as one of the world's favorite consumer electronics product, rapidly replacing analog videotape in the US and many other markets at prodigious rates. It is capable of offering a full feature-length, standard-definition movie in crisp rendition on TV. TV technology is itself in the midst of switching from analog to digital TV, with high-definition being the main draw. In fact, the US government has been advocating that switch over to digital TC, with both carrot and stick approaches, for nearly two decades, with only modest results--about 2% penetration. Under FCC herding, broadcasters are falling in the digital line--slowly, and sans profit. Meanwhile, delivery of HD content on portable media would be a great solution. Indeed, a new disk technology based on blue lasers is coming; but its widespread adoption may yet be four to five yeras away. But a promising new video codec--H.264/MPEG-4 AVC, the latest coding standard jointly developed by the Video Coding Experts Group (VCEG) of ITU-T and Moving Picture Experts Group (MPEG) of ISO/IEC, just might be the missing link. It offers substantial coding gains over MPEG-2, used in today's DVDs. With H.264, it appears possible to put HD movies on today's red-laser DVDs. Since consumers love DVDs, and HD--when they can see it, can H.264 and HD-DVD ignite a new revolution, now? It may have a huge impact on (H)DTV adoption rates.

The Department of Defense (DoD) Motion Imagery Standards Board (MISB) has adopted ITU-T Rec. H.264 (Baseline, Main, and Extended Profiles) to be the standard for applications constrained by low bandwidth channels (typically less than 1 Mb/s that may not be adequately supported by MPEG-2). H.264 will be carried over the MPEG-2 transport streams using ISO/IEC 13818-1:2000/FPDAM 3: "Information technology --Generic coding of moving pictures and associated audio: Systems, AMENDMENT 3: Transport of ISO/IEC 14496 part 10 [ITU-T H.264] video data over ISO/IEC 13818-1" (DRAFT). This is a part of a new principal called "Xon2" to support the "seamless" rollout of advanced video compression technologies without disrupting current and future operations and systems. "X" defines existing or future video compression technologies and "on2" refers to the use of MPEG-2 transport streams and files. The MISB predecessor VWG standardized on MPEG-2 (H.262) in 1996. "2on2" payloads have been successfully deployed using standards compliant MPEG-2 compressed video elementary streams, audio elementary streams, and SMPTE standard 336M KLV encoded metadata as MPEG-2 private data streams in support of unmanned aerial vehicle (UAV) operations. Building on this baseline "2on2" capability, "Xon2" will provide a migration path to inject improved compressions technologies, which will yield improved image quality and/or reduced bandwidths. NIMA’s Persistent Surveillance Office anticipates accelerating fielding of "264on2" using advanced video compression standard H.264 as described in this paper.

PixSil Technology's approach to hardware implementation of H.264 is highly modular. PixSil has designed its configurable hardware to be embedded within a System-on-chip (SOC). The processor manages most of the high-level frame management functions as well as set the parameters for control of the data stream. DMA engines direct the data stream to the hardware block. Many of the different profiles and levels of the H.264 standard are configurable by setting the desired parameters of the final system to the EDA software. Each block is selected to optimize the particular requirements of that level with the minimum amount of hardware. Clock speed may also be varied for power minimization. This concept is demonstrated using the Integer Transform Block of the H.264 algorithm stream. The paper illustrates how PixSil has designed the Integer Transform Block modules to meet the various throughput and I/O requirements for several of the different levels of H.264. Comparisons of area and power are made to a software-only implementation. Integration of the functional blocks completes the design of the full H.264 decoder. An SDRAM is the only external component required for PixSil Technology's FPGA/ASIC implementation of the decoder system.

In this paper, an H.264 encoder is proposed which incorporates a noise pre-filter with little additional complexity. The motion estimation process in the H.264 encoder, applied to multiple reference pictures, is re-used for temporal noise filtering. Significant objective and subjective improvement is observed for the proposed system versus a standalone H.264 encoder, with greater improvement at higher bitrates. For sequences with artificially generated noise, average PSNR improvements of 0.46 to 1.96 dB were obtained. The optimum number and type of pictures to use in the temporal noise filter was also studied. The proposed single stage encoder with noise filter system provides only a slight reduction in performance as compared to a more computationally complex two-stage system with separate noise filter and encoder.

This paper aims to provide an overveiw of the emerging video coding standard H.264/AVC in embedded environments typical for mobile streaming. After a description of the H.264 special network adaption layer and the required functionality of a compliant encoder packetizer and streaming server, reliability and bandwidth efficiency are being discussed using RTP and reliable RTR as possible candidates on the network layer. The main focus of the is paper is put on implementation issues for embedded systems including an analysis of the decoder complexity.

Embedding audio bits into images for transmission of video data alleviates the synchronization problem common in video transmission techniques. We continue work combining audio or other data bits and images into one file using digital watermarking techniques to correct the synchronization problem. The work compresses the file by using wavelet image coefficients and implementing bit plane coding. Our work encompasses incorporating five free variables into the watermark/compression technique. These variables are watermark robustness, number of coding iterations, number of image coefficients, number of watermarked data bits, and number of watermarked error correcting bits. By altering these variables, four measurements of the output will change. The four measurements are the watermarked bit error rate, the image quality, the compression ratio, and the amount of watermarked data. We will theoretically demonstrate how the variables impact these measurements. Experimental results on real video data will support our theoretical findings. By analyzing each video frame, an automated system will be able to choose the optimal values of the five variables to meet the given user constraints for the measurements.

With rapid advances in both system and networks, high-speed transport of massive media over the Internet has become a reality. Forward error correction (FEC) is a promising solution for the delay-constrained, reliable delivery of real-time continuous media. However, massive transport of media stream with FEC over high-speed network face lots of challenges such as a low bandwidth utilization or increasing processing overhead due to the inappropriate FEC combination. In this paper, reliable high-speed media transport with adaptive control of FEC is implemented and evaluated over a high performance networking testbed. Focusing on the impact of high-speed aspects to the adaptive FEC, the performance of proposed scheme is evaluated by emulating various network situations for quantitative comparison. The results demonstrate the performance improvement of the proposed scheme in supporting the reliable high-speed transport for the delivery of 3D stereo video.

Video over IEEE 802.11-based wireless LAN is facing lots of challenges due to the dynamically varying wireless channel and due to lack of appropriate QoS differentiation capability in the IEEE 802.11 MAC (medium access control). In this paper, differentiation mechanism coordinated by both video application and wireless MAC is adopted to realize a network-adpative video transmission over the wireless LAN. To support the required QoS differentiation for loss/delay sensitive video stream, modified version of EDCF (enhanced distributed coordination function) MAC is utilized, which provides loss/delay differentiation by controlling contention window size and distributed inter-frame space interval. The differentiation is then matched by the prioritization of video application, represented in the relative priority index (RPI). The network simulation with NS2 (network simulator) verifies that the proposed prioritization and modified EDCF improves the performance of video transmission over IEEE 802.11 wireless LAN.

In this paper, we propose a fast and efficient registration method that can be used for full reference objective video quality assessment. Instead of using full videos to register source video sequences and processed video sequences, we propose to use a number of reference frames which are selected under a certain criterion and select a number of sub-regions from the reference frames which have large variances. The wavelet transform is used to find the sub-regions. Since the registration is performed using the sub-regions, it can be fast. Experiments show promising results.

Streaming media applications over mobile IP networks suffer from playback disruptions resulting from handoff blackout period as well as bandwidth fluctuation. To overcome buffer shortage, pre-buffering technique can be adopted where the client stores sufficient amount of stream in advance. However, under the mobile IP handoff that may take up to several seconds, it is extremely difficult to sustain seamless playback. Inaccurate and conservative choice on the required buffering size can waste limited latency budget, resulting in quality degradation. In this paper, we are extending--from smooth handoff to fast handoff of mobile IPv6--the transient time analysis recently proposed to approximate transient time durations, STP (silent time period) and UTP (unstable time period). The approximated time periods are utilized to estimate the required buffering buffer size accurately. Network simulation result evaluted under simplified buffering strategies shows that the proposed scheme can provide appropriate guideline on the buffer parameters and thus can improve seamless streaming.

To guarantee end-to-end quality of service (QoS) delivery of rich multimedia consuming large bandwidth over IP, network resources have to be reserved in advance. To reserve the resources, advance reservation requests specifiy their desired service duration while conventional requests referred as immediate reservations do not. When these two types of requests are mixed, we need to balance them and provide an efficient resource sharing scheme. Focusing that the service time durations are partly flexible and may be adjusted with negotiation (although depending on the type of requests), we propose a new bandwidth scheduling scheme in this paper. The adopted models for service duration flexibility, user utility, and network cost are utilized to trade off the conflicting interests of provider and users and to balance the resource provisioning to both types of requests. By modeling the operation of resource manage (i.e., bandwidth broker) over the differentiated service (DiffServ) QoS provisioning, network simulation is conducted. The performance of proposed scheduling is then evaluated in terms of overall bandwidth utilization, total accomplished user utility, and reservation blocking rate.

Time Delay and Integration (TDI) sensors scan the image in one dimensions using a rectangular sensor array that integrates multiple time-delayed exposures of the same object. Due to physical constraints the TDI sensor element may have a staggered structure, in which the odd and the even sensors are horizontally separated. TDI image acquisition systems are usually employed in low signal to noise situations such as low light conditions or thermal imaging, or when high-speed readout is required. This work deals with analysis and restoration of images acquired by thermal staggered TDI sensors in the presence of mechanical vibrations. Vibrations during such an image acquisition process cause space variant image distortions in the scanning direction. These distortions include geometric warps (such as interlace comb effects) and blur. This situation is different from common case where the image degradation caused by motion is modeled as space invariant and can be treated by de-convolution techniques. The relative motion at each location in the degraded image is identified from the image using a differential technique. This information is then used to reconstruct the image using projection onto convex stes (POCS) technique. A main novelty in this work is the implementation of such methods to scanned images (column-wise). Restorations are performed with simulated images and with real mechanically degraded thermal images.

There are low target-to-background contrast, blurred edge and stronger noise in the infrared images which are always used in precise guidance. When applied to process the images, the traditional methods cannot get better processing result, because it cannot compress the noise effectively. But the soft mathematical morphological filter is non-linear filter and has many merits such as less sensitivity, higher computation speed etc. So it is well adapted to infrared images processing. The main performance of the soft morphological filter depends on different morphological exchange types and structuring elements. Unfortunately, there are no analytical criteria for choosing these structuring parameters. In order to obtain better image processing result, we must choose the most suitable structuring system based on specific task of image processing. In this paper, we take advantage of the profile and IR properties of ship to determine the shape and size of the structuring elements, and use the threshold theory to determine the values of structuring elements. The structuring system is applied to actual IR ship images. Some processing results are also listed in this paper. After the comparing of different results, a suitable structuring system is given at last.

The target detection of IR images is important in imaging precise guidance. The effect of the edge detection determines the accuracy and result of following processing directly. So it is a key step to recognize and segment the targets accurately and quickly. Because of the low target to background contrast, blurred edge and stronger noise in the infrared images, the traditional linear methods cannot get better processing result for they cannot compress the noise effectively. But the soft mathematical morphology can compress the noise effectively, detect the targets better, and complete processing in real time. So it is well adapted to infrared images processing. In this paper, we employed suitable structuring system based on the soft morphology theory and threshold theory to detect the edge of actual ship infrared image. All the images processing were simulated by MATLAB software. We discussed the merits and the shortcomings of the algorithm and listed some processing results. We also compared the algorithm with other traditional edge detection operators such as Robert;Prewitt and Sobel. The simulations results demonstrate that the algorithm is better than the traditional operators and can satisfy the requirements of the IR image edges detection. So the algorithm is of importance in practicality.

Stereo correspondence is a common tool in computer or robot vision, with numerous applications, such as determination of three-dimensional depth information of objects for virtual reality, autonomous vehicle and robot navigation, using a pair of left and right images from a stereo camera system. Computation time is an important factor in estimating dense disparity for the above applications. For of a pixel in the left image, its correspondence has to be searched in the right image based on epipolar line and maximum disparity search range. The intensity of a pixel alone in the left image does not have sufficient discriminatory power to determine its correspondence uniquely from the right image, thus other pixels in its neighborhood comprising a window is used for accurate estimation. In window-based approaches, this correspondence or disparity is conventionally determined based on matching windows of pixels by using sum of square differences, sum of absolute differences, or normalized correlation techniques. With a view to reduce the computation time, we propose a fast algorithm where it is not necessary to compute the window costs for all candidate pixels in the right image within the search range. To determine the correspondence of a pixel in the left image we just compute the window costs for candidate pixels in the right image whose intensities are different within a certain value to the intensity of the pixel in the left image. We applied our proposal to standard stereo images and found that we can easily reduce the computation time of about 30% with almost no degradation of accuracy.

Nonlinear vector median filters (VMF) and their variants represents one of the most popular approaches for color image processing. In this paper a novel effective method for detection and removal impulse noise in highly corrupted color images has been proposed. First, window operator based on an explicit use of spatial relations between color image elements to detect impulse noise is used. Then the spatially connected modification of VMF for removal of previously detected impulsive noise has been employed. The performance of the proposed detector and filter for detecting and suppressing of impulsive noise in test images is compared to conventional vector medium algorithms.

Regarding to big black speckle and cell like stripes in the IR images of a IR observation system introduced by the assembly precision, environment, the nonuniformity correction method and etc. after correction of the images for nonuniformity, an adaptive algorithm of nonuniformity correction based on neural network is introduced in this paper. And a real-time video signal processing system based on DSP and programmable devices is described in this paper in detail. Experimented with the IR observation system, the algorithm is able to despeckle images adaptively and the real-time realized in the hardware system proposed in this paper.

This paper presents new opportunities for applying linguistic description of the picture merit content and AI methods to undertake tasks of the automatic understanding of images semantics in intelligent medical information systems. A successful obtaining of the crucial semantic content of the medical image may contribute considerably to the creation of new intelligent multimedia cognitive medical systems. Thanks to the new idea of cognitive resonance between stream of the data extracted from the image using linguistic methods and expectations taken from the representaion of the medical knowledge, it is possible to understand the merit content of the image even if teh form of the image is very different from any known pattern. This article proves that structural techniques of artificial intelligence may be applied in the case of tasks related to automatic classification and machine perception based on semantic pattern content in order to determine the semantic meaning of the patterns. In the paper are described some examples presenting ways of applying such techniques in the creation of cognitive vision systems for selected classes of medical images. On the base of scientific research described in the paper we try to build some new systems for collecting, storing, retrieving and intelligent interpreting selected medical images especially obtained in radiological and MRI examinations.

A new algorithm of locally adaptive wavelet transform is presented. The algorithm implements the integer-to-integer lifting scheme. It performs an adaptation of the wavelet function at the prediction stage to the local image data activity. The proposed algorithm is based on the generalized framework for the lifting scheme that permits to obtain easily different wavelet coefficients in the case of the (N~,N) lifting. It is proposed to perform the hard switching between (2, 4) and (4, 4) lifting filter outputs according to an estimate of the local data activity. When the data activity is high, i.e., in the vicinity of edges, the (4, 4) lifting is performed. Otherwise, in the plain areas, the (2,4) decomposition coefficients are calculated. The calculations are rather simples that permit the implementation of the designed algorithm in fixed point DSP processors. The proposed adaptive transform possesses the perfect restoration of the processed data and possesses good energy compactation. The designed algorithm was tested on different images. The proposed adaptive transform algorithm can be used for image/signal lossless compression.

This paper presents a novel wavelet comrpession technique to increase compression of images. Based on extension of zerotree entoropy coding method, this method initially uses only two symbols (significant and zerotree) to compress image data for each level. Additionally, sign bit is used for newly significant coefficients to indicate them being positive or negative. Contrary to isolated-zero symbols used in conventional zerotree algorithms, the proposed algorithm changes them to significant coefficients and saves its location, they are then treated just like other significant coefficients. This is done to decrease the number of symbols and hence decrease number of bits to represent the symbols used. In the end, algorithm indicates isolated-zero coordinates that are used to change the value back to original during reconstruction. Noticeably high compression ratio is achieved with no change in image quality.

In this paper, a method tha combines maximal overlapped discrete wavelet transforms (MODWT) and dynamic time warping (DTW) is presented as a solution for dynamically detecting the hemodynamic response (HR). The MODWT is very effective in extracting only hemodynamic response portions from original signal without any shape distortion. The DTW is desirable for finding various shapes of hemodynamic responses dynamically. The DTW finds the optimal path with minimum cost between the reference signal and the reconstructed input signals by warping the signals in time domain to try to fit the reference. The MODWT-DTW method was evaluated using both simulated and experimental fMRI data. Simulations required identification of 500 synthetically generated hemodynamic responses and 500 randomly generated signals. To access the performance, receiver operating characteristic (ROC) curves were produced. The results indicate better performance for the MODWT-DWT approach compared to the more standard simple correlation methods. Finally, the MODWT-DWT procedure was used to characterize an fMRI data set with good correspondences between solutions derived from statistical parametric mapping techniques.

In this paper, the cubic spline interpolation (CSI) is shown to be performed by a direct computation for the encoding and decoding processes of image coding. A pipeline structure can be used to implement this new CSI. Such a new CSI algorithm can be used along with the JPEG standard to obtain the new CSI-JPEG codec and while still maintaining good quality of the reconstructed image for higher compression ratios. In this paper, it is shown that this new CSI-JPEG codec makes possible a pipeline compression algorithm that is naturally suitable for hardware implementation.

Iterative reconstruction methods, such as the expectation maximization (EM) algorithm and its extended approaches, have played a prominent role in emission computed tomography due to their remarkable advantages over the conventional filtered backprojection method. However, since iterative reconstructions typically are comprised of repeatedly projecting and backprojecting the data, the computational load required for reconstructing an image highly depends on the performance of the projector-backprojector pair used in the algorithm. In this work we compare quantitative performance of representative methods for implementing projector-backprojector pairs-ray-tracing methods, rotation-based methods, and pixel-driven methods. To reduce the overall cost for the projection-backprojection operations for each method, we investigate how previously computed results can be reused so that the number of redundant calculations can be minimized. Our experimental results demonstrate that, while the rotation based methods can be useful for simplifying the correction of important physical factors, the computational cost to achieve good accuracy is considerably higher than that of the ray-tracing methods.

In this paper, we propose an effective boundary matching based error detection algorithm using causal neighbor blocks in H.263 coded video to improve video quality degraded from channel error. The proposed algorithm first calculates boundary mismatch powers between a current block and one of its causal neighbor blocks. It then decides that a current block should be normal if all the mismatch powers are less than an adaptive threshold, which is adaptively determined using the statistics of the two adjacent blocks. In some expeirments under the environment of 16 bits burst error at bit error rates (BERs) of 10^-4~10^-3, it is shown that the proposed algorithm yields the improvements of maximum 20% in error detection rate and of maximum 3.5 dB in PSNR of concealed frames, compared with Zeng's error detection algorithm.

The infrared video image pseudo-color processing system, emphasizing on the algorithm and its implementation for measured object’s 2D temperature distribution using pseudo-color technology, is introduced in the paper. The data of measured object’s thermal image is the objective presentation of its surface temperature distribution, but the color has a close relationship with people’s subjective cognition. The so-called pseudo-color technology cross the bridge between subjectivity and objectivity, and represents the measured object’s temperature distribution in reason and at first hand. The algorithm of pseudo-color is based on the distance of IHS space. Thereby the definition of pseudo-color visual resolution is put forward. Both the software (which realize the map from the sample data to the color space) and the hardware (which carry out the conversion from the color space to palette by HDL) co-operate. Therefore the two levels map which is logic map and physical map respectively is presented. The system has been used abroad in failure diagnose of electric power devices, fire protection for lifesaving and even SARS detection in CHINA lately.

In the field of medical application, it is of great importance to adopt digital image processing technique. Based on the characteristics of medical image, we introduced the digital image processing method to the X-ray imaging system, and developed a high resolution x-ray medical sequential image acquisition and processing system that employs image enhancer and CCD. This system consists of three basic modules, namely sequential image acquisition, data transfer and system control, and image processing. Under the control of FPGA (Field Programmable Gate Array), images acquired by the front-end circuit are transmitted to a PC through high speed PCI bus, and then optimized by the image processing program. The software kits, which include PCI Device Driver and Image Processing Package, are developed with Visual C++ Language based on Windows OS. In this paper, we present a general introduction to the principle and the operating procedure of X-ray Sequential Image Acquisition and Processing System, with special emphasis on the key issues of the hardware design. In addition, the context, principle, status quo and the digitizing trend of X-ray Imaging are explained succinctly. Finally, the preliminary experimental results are shown to demonstrate that the system is capable of achieving high quality X-ray sequential images.

In this paper, we propose a real-time video watermarking algorithm for MPAG streams. Watermarking Technique has been studied as a method to hide secret information into the signals so as to discourage unauthorized copy or attest the origin of the media. In the proposed algorithm, we take advantage of compression information of MPEG bistreams to embed the watermark into I-, P-, and B-Picture. The experimental results show that the proposed watermarking technique results almost invisible difference between watermarked MPEG video and original MPEG video, and reduces the processing time. Moreover, it shows robustness against a variety of attacks as well.

Three-dimensional medical reconstruction has been a powerful technique in medical diagnosis, especially by using volume visualization of medical datasets such as those obtained from computed tomography (CT), magnetic resonance imaging (MRI) in recent years. A new medical volume reconstruction algorithm is presented in this paper. By examining the relations among three eigenvalues of local block based moment (LBBM) inertia matrix, the method defines transfer function in the domain of these eigenvalues. The eigenvalues and eigenvectors of the LBBM inertia matrix form a local coordinate system, which measures the local features such as flat, round, and elongated shapes of the object. The optimal window size of local voxel block is determined by experiments, and then two popular volume visualization algorithms are implemented to test the proposed transfer function design method. The proposed method can efficiently depict trivial features in medical datasets, especially useful in the rendering of structures with obvious shapes, such as round, flat, and elongated shapes. The new algorithm can not only result informative rendering results to the doctors, but also can efficiently reduce the time previously spent in trial-and-error process.

Full search block matching motion estimation requires a very large amount of computing power. To overcome this problem, many fast search algorithms have been proposed. But, all these algorithms do not satisfy both matching error performance and real time property at the same time. This paper proposes a novel fast block matching algorithm using temporal correlation and center biased behavior of motion vector. In proposed algorithm, we modify new three-step search algorithm to combine technique for temporal correlation of motion vectors and center biased assumption. In real video sequences, there are many overlapped motion vectors between adjacent frames. Thus, by finding these duplicated motion vectors with a simple search rule, the proposed algorithm dramatically reduces the computational amount with low quality degradation.

This paper presents new efficient method for motion estimation algorithm based on variable block size. The schemes allow the sizes of blocks to adapt to local activity within the block, and the number of blocks in any frame can be varied while still accurately representing true motion. This permits adaptive bit allocation between the representation of displacement and residual data, and also the variation of overall bit rate on a frame-by-frame basis. Especially, this paper approachs in direction of supplementing drawback of previous representative quad tree block matching algorithm and adds new method in order to improve the performance. Instead of the usual quad-tree segmentation, frame difference is computed for quad section and then homogeneity test is carried out for the largest block. Also, putting together of segmentation and re-merging strategy is employed which provides large computation reduction with little transmission overhead and raise higher image quality. Naturally, results are come into view as image quality is improved largely and computation load is decreased to 50-70 percent approximately.

In this paper, a novel image enhancement technique suitable for infrared image, dualistic sub-image enhancement based on two-dimensional histogram analysis and histogram equalization, is put forward. Firstly, the infrared image is segmented to two sub-images according to the correlation between the neighboring pixels, which is based on the two-dimensional histogram analysis. Then each sub-image is enhanced based on histogram equalization. At last, we get the result after the processed sub-images are composed into one image. The experiment result indicates that the algorithm can not only enhance image information effectively but also keep the fine part of original infrared image well. And this algorithm eliminates the drawback of traditional histogram equalization that the fine part is not easy to control and protect.

This paper presents a robust and efficient scene-based video watermarking method using visual rhythm in compressed domain. A visual rhythm is a two dimensional abstraction of the entire three dimensional video contents obtained by cutting through the video sequence across the time axis or by sampling a certain group of pixels in consecutive video frames. Knowing that scene changes can be easily detected using visual rhythm and video sequences are conveniently edited at the scene boundaries, such scene-based watermark embedding process is a logical choice for video watermarking. Temporal spread spectrum can be achieved by applying spread spectrum methods to visual rhythm. Additive Gaussian noise, low-pass filtering, median filtering and histogram equalization attacks are simulated for all frames. Frame sub-sampling is also simulated as a typical video attack. Simulation results show that proposed algorithm is robust and efficient against these attacks.

In this paper, object-based disparity estimation scheme using adaptive disparity-based segmentation is proposed and its performance is analyzed in terms of PSNR through comparison to that of the conventional disparity estimation algorithms. In the proposed algorithm, firstly we can get segmented objects by region growing from input stereoscopic image pair, which is region growing is a procedure that groups pixels or sub-region into larger regions, and then, the feature-based disparity estimation method in which Canny mask operator is used for detecting the edge information from the input stereo pair are used for extracting the feature value. And, the matching window size for reconstruction of stereoscopic image is adaptively selected depending on the magnitude of the feature value of the input stereo pair by comparing with the predetermined threshold value. That is, coarse matching is carried out in the region having a small feature value while dense matching is carried out in the region having a large feature value. Accordingly, in this paper, this new approach can not only reduce mismatching possibility of the disparity vector mostly happened in the conventional dense disparity estimation with a small matching window size, but also reduce the blocking effect occurred in the disparity estimation with a large matching window size and region growing methods often give very good segmentations that correspond well to the observed edges. From some experimental results, it is found that the proposed algorithm improves PSNR of the reconstructed image about 2.36~3.74 dB on the average than that of the conventional algorithms.

This paper proposes a novel fast intra prediction method to optimize H.264/MPEG-4 AVC video coding. In H.264, coding performance is enhanced through spatial prediction besides temporal prediction. In its luminance intra prediction, 4 modes for 16×16 block-size and 9 directional modes for 4×4 block-size are utilized, and the optimal intra mode is selected by R-D optimization, so the intra mode selection results in high coding complexity. To reduce the complexity of intra prediction, the fast hierarchical mode selection method is proposed with fewer modes to be examined, and intermediate computing results are reused. Therefore the intra prediction mode decision process is accelerated greatly. With the proposed fast intra prediction mode selection method, the intra prediction time can be reduced above 30% with less than 2% increase of bitrate, and up to 0.04dB loss in performance compared to the brute intra prediction mode selection method in H.264 reference software. The results are obtained by encoding with all I-frames, and even less performance loss can be achieved with the same time saving if encoding in I, P and B frames. So the complexity of computation can reduce constantly.

Demands for scalable delivery systems are increasing for Internet applications. Users want to receive content from a single source regardless of the consumer devices they are using PC, TV, PDA and mobile phone. To realize this type of application, we have developed a scalable delivery system based on a RTP JPEG2000 video stream format that we have proposed to IETF. This system can provide video delivery and Quality of Service from a single layered content for users who require different image quality/resolution/color depending on the device they are using. This system could be a next generation communication platform, allowing us to realize a ubiquitous value network by combining network and codec technologies.