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Evaluation function is an important item to measure the quality of images in auto-focusing systems. This paper introduces four categories of evaluation functions which are respectively based on gradient, correlation, statistics and transform. These functions formally differ from each other and their performances are not consistent when dealing with different images. The same function also performs...
This paper presents a new extended Chan-Vese level set method for ultrasound image segmentation. The proposed method introduces wavelet multiresolution analysis to create an edge representing mask to spot edge information of the image. While the evolution of the level set function, average edge energy of zero level set curve is calculated from the edge representing mask to control the evolving speed...
A new image fusion algorithm based on lifting wavelet transform is presented in this paper. The source images are decomposed using lifting wavelet transform respectively. Aiming at the coefficients of low frequency and high frequency, this algorithm choose a different rule to fuse the image. To the low frequency, the spatial frequency based on the neighborhood add consistency check is elected as the...
Based on the research on the existing SAR image compression technologies, this paper proposes a wavelet-based SAR image compression algorithm. The algorithm reduces the speckle noise impact on SAR images, improves the SAR image compression performance to some extent, so is an effective SAR image compression algorithm, and has some practical value.
As one of the most important human physiological signals, pulse signal contains a wealth of information which can reflect the change of emotions. In this paper, time-domain features and wavelet coefficient features through wavelet transform are extracted respectively from raw pulse signals. Then the improved Max-Min Ant System (IMMAS) combined with Fisher classifier is used for feature selection and...
The key point in the de-noising of Event-Related Potentials (ERP) is to give a clear visualization of ERP between different trials representing different types of emotions (Anger, Surprise, Fear, Sadness, Happiness, Neutral).We used 6 pictures representing each emotion as a stimulus to a male actor and recorded a total of 60ERP trials 10 for each emotion. A Mexican hat wavelet was used to de-noise...
Image fusion is one of the important techniques to enhance image information. A novel pixel-level image fusion scheme is presented based on multiscale decomposition. The wavelet transform is used to construct the wavelet coefficients of fused image using multiple operators according to different fusion rules. Comparison of fusion results of visible image and infrared image is given. It shows that...
Discrete digital image can achieve exact histogram specification through the strict ordering algorithm in. However, some edge information will be weakened. In this paper, a nonlinear filter algorithm in wavelet domain is proposed, which can solve the problem significantly. Firstly, the proposed approach utilizes wavelet transform to decompose the image and extract the wavelet coefficients. Secondly,...
Because of its multi-resolution analysis performance and great flexibility, wavelet packet transform is suitable for the narrowband interference. It can be realized by quadrate mirror filters, which decomposes the received signal into the n level to obtain a complete binary tree. According to received signal characteristic, we select an appropriate threshold. Compared with the threshold, the value...
During the course of noise reduction, wavelet threshold filtering algorithm can inhibite noise effectively, however Donoho threshold function hasn't self-adaption between dimensions and results in signal details' losing. Based on output signal of the thin-film thickness wideband monitoring system, it is processed by the improved Donoho threshold function whose threshold is added by micro-alignment...
Based on the characteristic of striping noise in remote sensing images, a new destriping technique for the improved threshold function using lifting wavelet transform is presented in this letter. It can overcome the shortcoming of the hard threshold function and soft threshold function. The lifting wavelet transform is easily realized. Also it is inexpensive in computer time and storage space compared...
In order to effectively extract the detail of the image characteristics so as to obtain a better identification effect, the paper proposes a texture analysis method for handwriting image based on integral wavelet transform. This method not only can extract the detail features of the texture image, but also is not sensitive to brightness, this characteristic is difficult to achieve for the traditional...
In this paper, a new multi-focus image fusion algorithm based on the Nonsubsampled Contourlet Transform (NSCT) is proposed. As a more effective multi-resolution analysis method, NSCT can give a better performance in image processing than the existing methods. Because Human Visual system(HVS) can only be sensitivity to regional characteristic rather than single pixel characteristic, region variance...
We consider the problem of blind audio source separation. A method to solve this problem is blind source separation (BSS) using independent component analysis (ICA). ICA exploits the non-Gaussianity of source in the mixtures. In this paper we propose a new wavelet based ICA method using Kurtosis for blind audio source separation. In this method, the observations are transformed into an adequate representation...
In this paper, an algorithm of position related channel character extraction and match localization based on ray-tracing is presented. Firstly the radio propagation of beacons is simulated and the time series for location is produced by using ray-tracing, and then wavelet transform and singular value decomposition are used for getting the character of location from the time series and build the character-location...
In the operation of substation, judgment of isolator's status is very important. But there are potential safety problems by the current method, such as electric shock accidents and outage accidents. This paper proposes a isolator's status image recognition technique based on Gabor wavelet and SVM(support vector machine). The isolator's status video images are preprocessed before an analysis of the...
In this paper, a novel face representation approach, Haar Local Binary Pattern histogram (HLBPH), is proposed to represent the face images. First, the face image is decomposed into four-channel subimages in frequency domain by Haar wavelet transform, and then the LBP operator is applied on each subimage to extract the face features. After that, a novel Haar LBP representation method (HLBPH) based...
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