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Background: The issue of medial image resolution enhancement is one of the most important topics for medical imaging that helps improve the performance of many post-processing aspects like classification and segmentation towards medical diagnosis. Objective: Our aim in this paper is to evaluate different types of pixel selection models in terms of pixel originality in medical image reconstruction problems. A previous investigation showed that selecting far original pixels has highly better performance than using near unoriginal/estimated pixels while magnifying some benchmarks in digital image processing. Material and Methods: In our technical study, we apply two classical inter-polators,... 

Covert exchange of information has been long a significant and highlighted affair. Numerous methods have been devised for the matter of which steganography is a popular one. Already applied in the past, the method has been massive used following the invention of computer. This paper discusses a new application of steganography in textiles in which information is hidden in the images on the clothes. In this way, information is first hidden by computer in images by a special method. Then the provided images are printed on clothes. The related information is extracted after scanning the images by relevant programs. © 2008 IEEE  

Determining the capacity of image for data hiding is a complex task. This capacity may be influenced by many factors such as the content of image and also Human Visual System (HVS). A few works on this topic are reported. In this paper we propose a new method for calculating capacity in gray scale images. Our method is based on measuring Smoothness and Connectivity of neighbors of a specific pixel in image bitplanes. This method can produce a signed integer for each pixel capacity such that the sign shows the modification in pixel value must be increasing or decreasing. Comparison with the existing methods showed that the proposed method gave better estimation for capacity of data hiding in... 

A novel burst correction coding for correction of bulk errors in block-based image coding is developed. The algorithm makes artificial correlation between image pixels that distorts the image. By choosing appropriate parameters, one can control this distortion to lie in acceptable ranges. Our method can exactly correct an erroneously decoded block when using lossless codecs. In the presence of lossy codecs, the algorithm encounters a processing error which makes a noisy image after correction. The Wiener filter is used to reduce this noise. Experimental results show that our method can correct corrupted large blocks in images; the ability that other previously reported approaches have not... 

In this paper a multi-scale image enhancement strategy using wavelets as applied to digital mammograms is presented. For multiresolution wavelet analysis redundant dyadic discrete wavelet transform is utilized to allow translation invariance and low resolution enhancement capability. Two alternative nonlinear gain adjustments, piecewise linear and Gaussian form of gain adjustment are used for coefficient modification for the enhancement of subtle details such as microcalcification and low resolution edges of different lesion types. The results of comparing these methods of gain adjustment are presented. This comparing has done by defining new parameters for measuring quality of image based... 

This paper presents a fuzzy approach for contrast enhancement, based on two multi-scale transforms, namely wavelet and contourlet transforms. Separability and nondirectionality of conventional 2D wavelet transform, makes it unsuitable for sparsely representation of curve or line shaped image objects. On the other hand, the contourlet transform is a good alternative for this purpose. In this paper, coefficient enhancement, both in wavelet and contourlet spaces, is carried out by making use of simple fuzzy rules. These rules make the enhancement procedure more understandable and flexible. With this method, the knowledge and experience of the expert from the distribution of the coefficients can... 

Radiographic inspection is the most appreciated technique among the other non-destructive testing methods due to producing unique finger print record as the film. Converting of radiographs to a digital format and further digital image processing is the best method of enhancing the image quality and assisting the interpreter on his evaluation. In this research, different algorithms were used for image enhancement and radiograph interpretation in MATLAB environment. A graphical user interface (GUI) was created for implementation of different algorithms. Both spatial and frequency (wavelet) domains techniques were used for image enhancement. Results showed that the defect recognition... 

An efficient multi-static millimetre-wave (MMW) imaging system is proposed with the aim of obtaining the information of an axially tilted object. It is known that a multi-static structure performs better than a mono-static array in detecting the reflected signal from axially tilted surfaces due to the specular reflection. Still, no efficient multi-static structure for the purpose of imaging tilted objects in view of the computational time, cost and image quality is proposed till now. The authors propose an efficient multi-static MMW imaging system tackle this issue with the minimum number of antennae. Furthermore, the small number of antennae in the proposed design and the proposed fast... 

Automatic image annotation (AIA) is an image retrieval mechanism to extract relative semantic tags from visual content. So far, the improvement of accuracy in newly developed such methods have been about 1 or 2% in the F1-score and the architectures seem to have room for improvement. Therefore, the authors designed a more detailed architecture for AIA and suggested new algorithms for its main parts. The proposed architecture has three main parts: feature extraction, learning, and annotation. They designed a novel learning method using machine learning and probability bases. In the annotation part, they suggest a novel method that gains the maximum benefit from the learning part. The... 

After expanding the use of computer and its affect on different aspect of life, the copyright issue has gained many attractions. For this purpose watermarking methods are proposed. In these methods a code is embedded into digital material that can be used to approve ownership, it can be visible or invisible to the user. On the other hand with the rapid growth of mobile phones, mobile telecommunication companies starting to add additional features to their mobile phones such as MMS (Multimedia Messaging Service) in order to attract more customers. MMS is a technology that allows mobile phones sending messages that includes multimedia objects esp. images. For copyright protection of images... 

In this paper we make use of M-band discrete wavelet transform (MDWT) and Wiener filter for speckle noise suppression of ultrasound images. Assuming multiplicative model for speckle noise, by applying logarithmic transform to noisy observation we convert multiplicative noise to additive one. Then, speckle noise can be reduced by taking the M-band wavelet transform of log-transformed observation and employing an adaptive thresholding technique. In order to improve the performance of this denosing approach, we propose a preprocessing stage which exploits Wiener filtering. Through this stage logtransformed observation is separated into two images and then each of these two images is denoised... 

A matrix pseudo inversion based method is developed for coding of images in real field in a way that at the receiver, one can restore the lost portions of the images. The proposed solution is similar to channel coding techniques, but it is done before source coding at the transmitter and after decoding of the compressed data at the receiver. Experiments show the effectiveness of the proposed solution in recove ring missed portions of the images and video frames. ©2007 IEEE  

In this paper we will address two major problems in mammogram analysis for breast cancer in MR-images. The first is classification between normal and abnormal cases and then, discrimination between benign and malignant in cancerous cases. Our proposed method extracts textural and statistical descriptive features that are fed to a learning engine based on the use of Support Vector Machine learning framework to categorize them. The obtained results show excellent accuracy in both classification problems, that proves the appropriate combination of our features and selecting powerful classifier i.e. Support Vector Machine leads us to a brilliant outcome  

An extended version of Lagrange interpolation is developed for coding of images in real field in a way that at the receiver, one can restore the lost portions of the images. The proposed solution is similar to channel coding techniques, but it is done before source coding at the transmitter and after decoding of the compressed data at the receiver. Our proposed solution is faster than the other one reported in the literature when the size of damaged blocks is large  

In this paper we propose a new method for image noise reduction based on wavelet transform. In this method we: introduce an improved version of thresholding neural networks. (TNN) by utilizing a new class of smooth nonlinear thresholding functions as the activation function. Using this approach we will find the best thresholds in the sense of minimum mean square error (MMSE). Then using, TNN with obtained thresholds, we employ a cycle-spinningbased technique to reduce image artifacts. Experimental results indicate that the proposed method outperforms several other established wavelet denoising techniques, in terms of Peak-Signal-to-Noise-Ratio (PSNR) and visual quality. © 2007 IEEE  

One of the main issues in colour image processing is changing objects' colour due to colour of illumination source. Colour constancy methods tend to modify overall image colour as if it was captured under natural light illumination. Without colour constancy, the colour would be an unreliable cue to object identity. Till now, many methods in colour constancy domain are presented. They are in two categories; statistical methods and learning-based methods. This paper presents a new statistical weighted algorithm for illuminant estimation. Weights are adjusted to highlight two key factors in the image for illuminant estimation, that is contrast and brightness. The focus was on the convex part of... 

One of the main issues in colour image processing is changing objects' colour due to colour of illumination source. Colour constancy methods tend to modify overall image colour as if it was captured under natural light illumination. Without colour constancy, the colour would be an unreliable cue to object identity. Till now, many methods in colour constancy domain are presented. They are in two categories; statistical methods and learning-based methods. This paper presents a new statistical weighted algorithm for illuminant estimation. Weights are adjusted to highlight two key factors in the image for illuminant estimation, that is contrast and brightness. The focus was on the convex part of...