In this paper the new two-dimensional (TD) adaptive filter algorithms are introduced. the presented algorithms are TD variable step-size (VSS) normalized least mean squares (TD-VSS-NLMS) and TD-VSS affine projection a...
详细信息
In this paper the new two-dimensional (TD) adaptive filter algorithms are introduced. the presented algorithms are TD variable step-size (VSS) normalized least mean squares (TD-VSS-NLMS) and TD-VSS affine projection algorithms (TD-VSS-APA). In these algorithms, the step-size changes during the adaptation which leads to the low steady-state mean square error (MSE), and fast convergence speed. We demonstrate the good performance of the derived algorithms in TD system identification and adaptive noise cancellation in digital images for image restoration.
this paper focuses on shape description for machine printed Farsi/Arabic subwords retrieval. Fourier descriptor (FD) has been used frequently for shape retrieval applications. In this paper we proposed a simple and ef...
详细信息
this paper focuses on shape description for machine printed Farsi/Arabic subwords retrieval. Fourier descriptor (FD) has been used frequently for shape retrieval applications. In this paper we proposed a simple and effective FD based technique for subwords retrieval. In this method, the small number of global parameters is used to eliminate dissimilar subwords. To investigate the efficiency of the proposed method, it is compared with six common FD signatures on a database including Farsi subwords of 4 fonts and 3 sizes. Experimental results show that the proposed method outperforms the others.
Immuonohistochemically images of meningioma which are stained by ki67 marker contain positive and negative cells. Accurate counting the number of positive and negative cells in such images play a critical role in diag...
详细信息
Immuonohistochemically images of meningioma which are stained by ki67 marker contain positive and negative cells. Accurate counting the number of positive and negative cells in such images play a critical role in diagnosing different type of meningioma cancer. Since pathological images of meningioma contain complex cell cluster accurate cell counting methodology is a major challenge for pathologist physicians. In this paper we provide a computer aided algorithm for detecting proliferative cells and mitosis index in immunohistochemically images of meningioma. In the first stage of the algorithm fuzzy c-means clustering was used to extract positive and negative cells based on CIElab color space. In the second stage, ultraerosion operation was applied to count the number of individual and overlapped cells. Experimental result show that the proposed algorithm is able to overcome some disadvantage of traditional approaches with acceptable accuracy by pathologist physicians.
We present a modified Temporal Conditional Random Fields framework for modeling and predicting object motion. To facilitate such a powerful graphical model with prediction and come up with a CRF-based predictor, we pr...
详细信息
We present a modified Temporal Conditional Random Fields framework for modeling and predicting object motion. To facilitate such a powerful graphical model with prediction and come up with a CRF-based predictor, we propose a set of new temporal relations for object tracking, with feature functions such as optical flow (calculated among consequent frames). We evaluate our proposed Temporal Conditional Random Field method with real and synthetic data sequences and will show that the TCRF prediction is nearly equivalent with result of template matching. Experimental results show that our proposed method estimates future target state with zero error until target dynamic changes. Our proposed modified CRF method with simple and easy to implement feature functions, can learn any target dynamic, thus, it can predict next state of target with zero error.
In this paper a novel logarithmic edge detection algorithm is presented. the algorithm is an extended and modified version of PLIP Sobel edge detection algorithm. Six new kernels are suggested to achieve a higher leve...
详细信息
In this paper a novel logarithmic edge detection algorithm is presented. the algorithm is an extended and modified version of PLIP Sobel edge detection algorithm. Six new kernels are suggested to achieve a higher level of independence from scene illumination and provide obvious distinction between edge and non-edge pixels. We present experimental results for this method, and compare results of the algorithm against several leading edge detection methods such as Sobel, Canny and conventional logarithmic edge detection. To compare results objectively, we computed edginess judging index (EJI) for edge detection algorithms. the proposed technique is effective, as demonstrated by computer simulations, conceptually straight forward, and easy to use.
In this paper, a novel algorithm for image encryption based on SHA-512 is proposed. the main idea of the algorithm is to use one half of image data for encryption of the other half of the image reciprocally. Distinct ...
详细信息
In this paper, a novel algorithm for image encryption based on SHA-512 is proposed. the main idea of the algorithm is to use one half of image data for encryption of the other half of the image reciprocally. Distinct characteristics of the algorithm are high security, high sensitivity and high speed that can be applied for encryption of gray-level and color images. the algorithm consists of two main sections: the first does preprocessing operation to shuffle one half of image. the second uses hash function to generate a random number mask. the mask is then XORed withthe other part of the image which is going to be encrypted. the aim of this work is to increase the image entropy. Both security and performance aspects of the proposed algorithm are analyzed and satisfactory results are achieved in various rounds.
this paper presents a real-time algorithm of accurately identifying helipad and estimating the state information for landing an unmanned aerial helicopter autonomously via computervision. the algorithm estimates the ...
详细信息
this paper presents a real-time algorithm of accurately identifying helipad and estimating the state information for landing an unmanned aerial helicopter autonomously via computervision. the algorithm estimates the instantaneous attitude and position parameters of the helicopter relative to the helipad from continuously tracked points using the optical flow method. the vision system, consisting of a calibrated monocular camera, a helipad and an experiment platform, can perform imageprocessing, helipad recognition, feature extraction, target tracking and motion estimation. the experimental results show that the algorithm is accuracy, robust and fast.
the transmission of block-coded images over wireless channels results in lost blocks. In this paper, we propose a new error concealment method for covering up the high packet losses of an original image after its tran...
详细信息
the transmission of block-coded images over wireless channels results in lost blocks. In this paper, we propose a new error concealment method for covering up the high packet losses of an original image after its transmission through an error-prone channel. In this scheme, Discrete Wavelet Transform (DWT) is applied to each block of the original image in order to produce a lower resolution copy of the each block. then, we choose approximation coefficients of each block as replica of the block and embed it into a remote block of the image in the spatial domain. It is shown that the proposed scheme provides significant improvement over existing algorithms in terms of both subjective and objective evaluations. this technique can be implemented for wireless channels to combat degradations in a backward-compatible scheme.
there are several studies in the literature comparing different approaches. Most of these comparisons are based on objective tests (i.e.; efficiency and effectiveness of the approaches are obtained and compared). In t...
详细信息
there are several studies in the literature comparing different approaches. Most of these comparisons are based on objective tests (i.e.; efficiency and effectiveness of the approaches are obtained and compared). In this paper we conducted a novel subjective test, where human perception is incorporated to the evaluation process. Five known methods in the image retrieval literature are implemented and compared for closeness to human perception and also for their search time. Here, 1) similarity, 2) symmetry, and 3) area of trademarks retrieved by five different methods are evaluated and scored by humans. Experimental results illustrate that the correlation method is the nearest to human's perception in all fields. Experiments also show that the EPNH method is more efficient (much more shorter time) than the correlation method, while the semantic powers of these two are close together.
Defects on the Pipeline surface such as cracks cause main problems for governments, specifically when the pipeline is covered under the ground. Manual examination for surface defects in the pipeline has several disadv...
详细信息
Defects on the Pipeline surface such as cracks cause main problems for governments, specifically when the pipeline is covered under the ground. Manual examination for surface defects in the pipeline has several disadvantages, including varying standards, and high cost. In this paper, a combination of two algorithms based on mathematical morphology and curvature evaluation for segmentation of defects is proposed. then, we use fuzzy k-means clustering to classify pipe defects. the proposed method can be completely automated and has been tested on more than 250 scanned images of petroleum pipelines of Iran.
暂无评论