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We describe a method for defect detection and classification for collections of digital images of historical book documents. Undistorted text images from various books characterized by strong variation of language, font and layout properties are discriminated from typical errors in digitization processes such as occlusion by an operator's hand, visible book edge or image warping artifacts. A bag of...
Recently, handwritten digit recognition using higher level features has got more promising results than conventional ones using intensity values, where the higher level features are considered as features of simple strokes in images. Although the state-of-the-art performance is very impressive, there is still room to improve better in both accuracy and computation complexity. In this paper, we propose...
In this paper, we present a promising method for binarization of historical and degraded document images, based on texture features. The proposed method is an adaptive threshold-based. This latter is computed by using a descriptor based on a co-occurrence matrix. The proposed method is tested objectively, using DIBCO dataset degraded documents and subjectively, using a set of ancient degraded documents...
In this paper we propose a system for word spotting in Arabic historical document using Ridgelet transform and Dynamic Time Warping (DTW). First, a preprocessing and segmentation processes are applied to all document pages to create a word image dataset. Keeping each word into its original size, Ridgelet descriptor is generated without applying the normalization criteria for Radon transform, where...
A new methodology is presented which enables the use of optical free-forms instead of classical beamers for fringe projection based optical 3D surface measurements. Although optical free-forms allow the generation of approximately sinusoidal fringes for phase shifting profilometry, they cannot produce Gray code like pattern for robust phase unwrapping. The principal idea of this work is the consideration...
A new methodology for parameter free lens distortion determination is introduced providing high precision capacity and low effort by omission of subsequent camera calibration. It uses a plane grid pattern with precise geometry. The method is based on the iterative estimation of the distortion using several views from different observation positions by fitting a projective transform of the known grid...
The detection of salient regions is an important preprocessing step for the analysis of mesh surfaces. The detected salient region is a reflection of perception-based regional importance for surfaces. It finds many 3D applications, such as mesh simplification, registration, segmentation and compression. In this paper we propose a novel method for the detection of saliency in a 3D surface. Our method...
The domain of image processing for cell microscopy presents non-trivial challenges that must be addressed for consistent image quality. One such challenge concerns the loss of focus as a result of cellular processes, where cell objects may move or change their morphology and, as a result, lie outside of the depth-of-view of the lens. This paper presents two approaches to addressing this problem; namely,...
In this paper a novel method for computing parallax maps from monocular and uncalibrated video sequences is described. Acquired frames are processed pairwise, starting from a first reference and progressively integrating information coming from subsequent frames in temporal order using a Kalman filter. In this way, temporal stabilization of the generated maps is obtained as well as more consistency...
A sparse coding based approach for background subtraction is proposed in this paper. The background model is composed from a K-SVD dictionary and a set of mean coefficients associated to each image location. Due to the use of sparse coding, our approach has a regional character. The recovered value of a pixel is obtained by reconstructing the surrounding image patch. In order to avoid problems introduced...
In this paper a real-time simulcast multi-view video coding based on three-dimensional discrete wavelet transform (3D DWT) is considered. An efficient rate-distortion criterion of skipping spatial subbands is proposed. A processing of subbands is done in a group of frames from low frequency to high-frequency temporal subbands and from low frequency to high-frequency spatial subbands. If for the processed...
Video compression and encryption became very essential in secured real time video transmission. Applying both techniques simultaneously is one of the challenges where the size and the quality are important. In this paper we propose a new technique for video compression and encryption. The compression bases on hybridizing DWT, DCT and vector quantization. The compression algorithm includes two major...
This paper presents a new generic algorithm for image interpolation as well as lossless image coding. Main motivation behind the work is to reduce computational complexity involved in using Least Square Error Minimization (LS). The proposed method down samples the given image to its quarter size and then to its (1/16)th size. For each downsampled image, the least Square predictors are then obtained...
In this paper, we show how the DCT blocks can be transcoded to wavelet subbands for image deblocking in the wavelet domain. The approach is based on the transcoding of DCT blocks to wavelet coefficient subbands directly in the transform domain. The transcoding uses filtering (wavelet analysis) along with re-sampling (down) operation in the block DCT space. To perform transcoding, linear filtering...
We propose an automatic method to quantitatively describe the spatial organization governing populations of biological objects, such as cells, which exist in stationary histology images. This quantification is of prime importance when striving to compare different tumoral models in order to evaluate potential therapies. We compare two animal models of colorectal cancer. Our approach is based on the...
We present an object-oriented simulator for 3D digital breast tomosynthesis (DBT) system using C++ programming language. The simulator is capable of implementing different iterative reconstruction and total variation (TV) regularization methods on the real world phantom models. A user friendly graphical user interface (GUI) helps users to select and run the desired methods on the designed phantom...
This paper presents a study on the role of shape in the detection of melanomas in dermoscopy images. The contribution of shape-related features was assessed by developing a Computer-Aided Diagnosis (CAD) system whose classification is solely based on this type of features. Four shape descriptors were used, first separately and then simultaneously, to describe the images. Image segmentation was performed...
The classification of skin lesions in dermoscopy images depends on three critical steps: i) lesion segmentation, ii) feature extraction and iii) feature classification. Lesion segmentation plays an important role since segmentation errors may jeopardize the other two steps, leading to erroneous decisions. This paper studies the robustness of a skin lesion classifier based on a Bag-of-features approach...
The Hough transform is a classical pattern recognition algorithm used to detect straight lines, circles and ellipses in images. Recently, algebraic geometry arguments have been applied to generalize this approach to special classes of curves. Here we provide preliminary results showing that this method can be utilized for the recognition of compact bone profiles in clinical X-ray tomography images...
High Dynamic Range (HDR) imaging is rapidly emerging as an innovative approach for digitally representing and reproducing real scenes with a wide range of intensity levels, which can be hardly managed by current standard methods for image capture and display. In order to protect the intellectual property of HDR images, a novel blind multi-bit watermarking method exploiting both their peculiar characteristics...
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