A PACS Scheme Based on High-speed Ethernet

Picture archiving and communication system(PACS) is the key way to realize the medical images modernized management, the main work of which is to ensure the medical image information can be transmited and applied with high efficient. The Ether net is a popular local net. The author has described a PACS scheme based on high speed Ether net, with which, many modular functions (medical image sampling, medical image processing, medical image storage, medical image management, medical image review, medical image transmission, medical image edit, et al) can be realized. Also, the PACS can be fused with HIS.     

Multi-yesolution Encoding of Medical Image in PACS

It is necessary to transmit and review medical images effectively in PACS (Picture Archive & Communication System, PACS) , and multi -resolution encoding can improve image compression efficiency. The progressive property of 2D image wavelet transform is studied, and a multi - resolution medical image encoding method is described. This encoding method means that, the lower frequency subimage in wavelet domain should be encoded prior to those higher frequency subimage. Also, in the medical image process of transmission and reviewing, the same order will be followed. The experiment has improved that the proposed method can speedup the medical image transmission and reviewing in PACS effectively.     

A Vector Quantification Image Coding Scheme Based on Wavelet Transform

The paper proposes an image compression and coding scheme based on discrete wavelet transform (DWT), which makes the best of the relativities among original image and coefficients of wavelet, the relativities among pixels of subimages, the relativities among directions of subimages. Human visual specialities were considered, so the compression scheme leads up to make full use of the statistical redundancy and visual redundancy of image. To get high compression ratio and good quality of image, the coefficients of image working on the quality of image greatly were reserved accurately, but the coefficients of image working on the quality of image slightly were quantified roughly. Also, the regrouping and coding of the coefficients could be used universally. The experimental results show that the compression method is provided with simply calculating, little time for coding and decoding and satisfying quality companied with high compression ratio.     

A Context Model of Wavelet Coefficients for Image Compression

Through the combination of the idea of the linear prediction used in the GlicBawls coding scheme and the idea of the quantization taken in the CALIC coding scheme to reduce the number of contexts, a new context model of wavelet coefficients for image compression is proposed. Wavelet coefficients are encoded by the arithmetic encoder, with the contexts formed by quantizing linear prediction values. Experimental results show that the model achieves higher lossless compression rate of image than lossless SPIHT and lossless EBCOT used in JPEG2000. In addition, by exploiting the multiresolution property of wavelet, the model can compress the transformed image for progressive resolution and earn higher compression rate for each scale of the image than EBCOT.     

Filter Design of Wavelet Transform for 2-D Image

The filter design is the key to 2-D image wavelet transform. Based on the studying of image properties and 1-D wavelet theory,the authors describe a parasymmetry boundary extension method and realize 2-D discrete wavelet transform by means of 1-D wavelet transform according to correlation of adjacent pixels. Also,it is proved that the discrete wavelet transform of inverse data stream in row and the sign of discrete detail signal will be inversed,and that a filter of wavelet transform based on symmetry of bi_orthogonal filter is constructed. The test has proved the fine reconstruction and perfect SNR.     

Framework of M-channel Systems and the Best Symmetric Extension

In image compression based on wavelet transform, the borders of images have to be processed in advance so as to reduce the distortions around the borders. An efficient way for this problem is symmetric extension. There are different types of symmetric extension methods. The paper presents the best symmetric extension and gives a design algorithm. Using the algorithm, we obtain the scheme of extending and windowing the signals in general best M-channel analysis/synthesis system.     

Practical Method of High-Speed Access for Medical Digital Image Sequences

The high-speed access for medical digital image sequences was restricted to special device and complicated system in the past. The authors present a new method of high-speed access for medical digital image sequences which can be performed on general computer by means of the combination of Serial ATA(SATA) and Redundant Array of Independent Disk(RAID).Then they introduce the scheme of system configuration and software program. Lastly the testing result is given and the speediness,cheapness and conveniency of this method are elucidated.     

An algorithm of image processing based on discrete wavelet transform compression and chaotic scrambling

An algorithm was proposed in view of the combination of image compression and encryption. We got the approximate part and three detail parts after transforming the image with discrete wavelet transform (DWT), and compressed the image by modifying the detail parts by a given threshold value based on human visual systems. And then, we encrypted the image by scrambling the approximate part because this part held mostly of the energy. Last, a compressed and encrypted image can be achieved after DWT. Simulation result shows a good effect on the combination of compression and encryption.     

Embedded Image Coding on Wavelet Coefficients

The modeling of wavelet coefficient for still image compression is studied.Firstly,through simulation experiments on three classical wavelet coefficient models(i.e.,EZW model,SPIHT model/and EBCOT model),it is shown that SPIHT is superior to EZW in terms of compression performance(0.6 dB higher)and the compression performance of EBCOT is significantly better than that of SPIHT on average. Then the cause for such performance differences is explained through the analysis of models.Finally a new wavelet coefficients model is proposed which combines the advantages of the three classical models.Experimental results show that our model is better than the above mentioned three models with respect to compression ratio.     

Fusion method for infrared and visible light images based on image segmentation and stationary wavelet transform

A novel image fusion method based on image segmentation and stationary wavelet transform (SWT) is proposed to improve the visual effect of fused infrared and visible light images. Infrared image is firstly separated into object and background region utilizing Otsu combined with edge detection. Then a multiresolution decomposition using SWT is made to the background region of the infrared image and the visible light image. Neighborhood spatial frequency and absolute value are adopted as fusion rules in low-frequency and high-frequency coefficients. The background fused image is reconstructed by inverse SWT. The final infrared and visible light fused image is obtained by fusing the background fused image and the object region of infrared image base on weighted fusion rule. The experimental results show that the object information of the infrared image is obviously highlighted and the scene information of the visible light image is well represented. The visual effect of fused image is improved efficiently by utilizing the proposed method. The proposed method works better than the traditional Laplacian Pyramid and wavelet transform fusion algorithms in terms of standard deviation, comentropy and mutual information. Experimental results verify its effectiveness.     

A New Still Picture Compression Coding Algorithm

A new still picture compression coding algorithm,WH JPEG algorithm have been proposed due to JPEG baseline system having problem.Advantages of the algorithm include:remove blocking effect,higher compression rate,satisfactory multiform demand by contorlling number of layer.     

A Method for Getting Directional Image from Fingerprint Based on Directional Elemental Pixel Sets

By the definition and interpretation of directional elemental pixel sets, a method for getting the directional image from the binary fingerprint image using the statistic characteristics of DEPS is presented in this paper. This method is better than traditional methods in processing speed, computing complexity and resisting noises. The directional image got by this method is used to the matching of ridges frame in a fingerprint verification system, and the testing result shows that the method is effective.     

Detection Method for R-Wave of ECG Signal With Wavelet Transform

The R-wave of ECG signal represents the electrical activation of the ventricles, which initiates ventricle contraction, and the typical peak value singular signal, so the R-wave of ECG signal is localized precisely and analyzed accurately using the wavelet transform. The principium of the precise detection method for R-wave in ECG signal is researched. The special properties of Mexican hat wavelet in time-domain are analyzed, too. This wavelet has every order continuity, symmetry, exponential attenuation and one vanishing moment. For this reason, the mexican hat wavelet basis has the excellent localization and analyzing precision. Using the MIT/BIH (Massachusetts Institute of Technology / Boston's Beth Israel Hospital) Arrhythmia Database and the applications in clinic, the precise detection method can detect accurately and localize precisely to the R-wave in ECG signal in the serious noise signal. This method has the quite high locating precision (its error is not more than one sampling point and the points of the R-wave in ECG signal about 80 percent are localized precisely) and analyzing accuracy (no accumulative error). The real-time of the method is excellent, and the real-time detection to the R-wave of ECG signal can achieve using this method.     

Expressing Method of the Edge of Image Region

A Expressing method of the edge of image region is important in the studing and applying of image. It will influence the veracity of expressing and recognizing of region. A free curve of created method which discussed by the author have been used to approach the edge of image region. Since the free curve pass through the given points and need not converse compute, the speed of creating curve is very quickly. Also the curve are smoothness and fairness, the curve is close to edge of image region. The experiment presents the efficiency of the method.     

A New Method of Diesel Engine Fuel System Fault Diagnosis

A method of diesel engine fuel system fault diagnosis based on wavelet transform and fuzzy C-means clustering is presented. Five characteristic parameters of reflecting fault state are distilled with wavelet transform of pressure wave of high-pressure oil pipe of diesel. The theory and generic approach of fuzzy C-means clustering algorithm (FCM) is given, and the validity of evaluating fuzzy clustering making use of partition coefficient, partition entropy and parting coefficient is pointed out. Identification of fault mode can be completed utilizing standard fault character modes established by FCM algorithm, and calculating and comparing the similarity degree between this standard mode and sample. The arithmetic is applied to all kinds of typical faults diagnose in the diesel engine fuel system. Measuring results indicate that the precision of fault diagnosis is increased with the analysis of wavelet and FCM.     

A Kind of Hardware Realization Method of Solid State Image Sensor Signal Equidistance Subdivision

Basing on the sampling and recovery theorem, this paper investigates the principle of equidistance subdivision for image sensor export signal by hardware circuit.The mechanism of the hardware equidistant subdivision and the function of the image sensor are analyzed, and the circuit diagram of the hardware equidistant subdivision is given with the export signal of the image sensor. Based this, the simulated experiment is a testing of the laser diffraction pattern by electronic CAD PSpice software. This simulated experiment shows that the method with the hardware equidistant subdivision can improve highly its measured accuracy (especially the device of low bit and big central distance), in Laser diffraction measure fine wire diameters, so this experiment can prove its true of the theoretical analysis. This method also eliminates nonuniformity of the device, to large extent, by low pass filter.