44 research outputs found
Power LBP: A Novel Texture Operator for Smiling and Neutral Facial Display Classification
AbstractTexture operators are commonly used to describe image content for many purposes. Recently they found its application in the task of emotion recognition, especially using local binary patterns method, LBP. This paper introduces a novel texture operator called power LBP, which defines a new ordering schema based on absolute intensity differences. Its definition as well as interpretation are given.The performance of suggested solution is evaluated on the problem of smiling and neutral facial display recognition. In order to evaluate the power LBP operator accuracy, its discriminative capacity is compared to several members of the LBP family. Moreover, the influence of applied classification approach is also considered, by presenting results for k-nearest neighbour, support vector machine, and template matching classifiers. Furthermore, results for several databases are compared
Robust local similarity filter for the reduction of mixed Gaussian and impulsive noise in color digital images
Adaptive Impulsive Noise Removal in Color Images
In this paper a novel adaptive filtering scheme for impulsive noise removal in color images is presented. The noise detection algorithm is based on the concept of aggregated distances assigned to the pixels belonging to the filtering window. The value of the difference between the accumulated distance assigned to the central sample and to the pixel with the lowest rank serves as an indicator of the presence of impulses injected into the image by the noise process and adaptively influences the filter output which is a weighted mean of the central pixel of the filtering window and the vector median of its samples. The obtained results show that the proposed filter outperforms existing impulse noise removal techniques for low noise contamination and can be used in various applications in which the detail preserving reduction of impulses plays an important role.APSIPA ASC 2009: Asia-Pacific Signal and Information Processing Association, 2009 Annual Summit and Conference. 4-7 October 2009. Sapporo, Japan. Oral session: Low-level Color Image Processing (7 October 2009)
Ranked-Based Vector Median Filter
In this paper a new class of noise attenuating and edge enhancing filters for color image processing is proposed. The new filtering design is based, like the vector median filter, on the minimization of aggregated weighted distances between pixels in a filtering window. The weights which are assigned to the sequence of the sorted distances are decreasing functions of their ranks. In this way, the largest distances are taken to the aggregated distance with smallest weight, which ensures much better noise reduction properties of the described filter. Additionally, the proposed method has a unique ability to strengthen the edges of the noisy image objects. This unique deblurring property can be useful in many applications which require reliable impulse noise reduction and efficient edge sharpening of color images.APSIPA ASC 2009: Asia-Pacific Signal and Information Processing Association, 2009 Annual Summit and Conference. 4-7 October 2009. Sapporo, Japan. Poster session: Image, Video, and Multimedia Signal Processing 1 (5 October 2009)
Colorization of Medical Images
Colorization is a term used to describe a computerized process for adding color to black and white pictures, movies or TV programs. This process can also be used to convert the gray scale medical images to their colorized version, as color increases the visual appeal of an image and it also makes a medical visualization more attractive. Changes in color are more easily perceived than changes in shades of gray and therefore this procedure makes the interpretation and understanding of the image easier. During colorization process a scalar value representing pixel's intensity is being replaced by a vector in a given color space. Since the mapping between intensity and color has no inherently correct solution, human interaction and external information usually plays a large role. In this paper we present a novel colorization method based on the morphological distance transformation which considers the image structures to automatically propagate the color inserted into the image by a user. The effectiveness of the algorithm allows to work interactively and to obtain desired results promptly after providing the color information. In the paper we show that the proposed technique allows for high quality colorization of medical images.APSIPA ASC 2009: Asia-Pacific Signal and Information Processing Association, 2009 Annual Summit and Conference. 4-7 October 2009. Sapporo, Japan. Oral session: Low-level Color Image Processing (7 October 2009)