Bilateral filter

About: Bilateral filter is a research topic. Over the lifetime, 3500 publications have been published within this topic receiving 75582 citations.

System and process for repairing a binary image containing discontinuous segments of a character

Abstract: A system is provided for repairing a binary image image containing discontinuous segments of a character. The binary image comprises a two-dimensional array of pixels, and the system comprises a device for storing the binary image, and a processor for performing various steps, including (1) creating a morphological filter, (2) mapping the morphological filter onto a selected region of the binary image, wherein each element of the morphological filter corresponds to a pixel of the binary image, (3) for each of the elements of the morphological filter of the first filter type, determining whether the corresponding pixel of the binary image is set and any of the pixels of the binary image corresponding to the elements of the morphological filter of the second filter type are set, and (4) setting the pixel of the binary image corresponding to the center element of the morphological filter, responsive to the previous step.

Apparatus and method for foreground detection

Abstract: An apparatus and a method for fast foreground detection are provided. A foreground characteristic value calculation module calculates a foreground characteristic value by using an image intensity of each pixel in a target image and a background intensity of a corresponding pixel in a background model. A first filter determines a first threshold and a second threshold according to at least one scenic factor for capturing the target image and filters out non-foreground pixels having their foreground characteristic value between the first threshold and the second threshold from pixels in the target image. A second filter determines an image difference condition and a chroma similarity condition according to the scenic factor and filters out non-foreground pixels having their foreground characteristic value satisfying the image difference condition and the chroma similarity condition from pixels left by the first filter. Pixels left by the second filter are served as foreground pixels.

Ultrasound Image Denoising Using Wavelet Thresholding Methods in Association with the Bilateral Filter

Abstract: Ultrasound imaging has been widely used in medical diagnosis in modern medicine. Although widespread, it presents low-resolution images, typically degraded by speckle noise, which requires the use of image-processing techniques aiming at improving the image quality and allowing a proper medical diagnosis use. This paper presents a new association based on S-median thresholding and the fast bilateral filter for speckle noise reduction. In order to validate the results, the proposed method was analyzed and compared with two others thresholding methods. The image quality improvement is evidenced by an increase of 14.13% in PSNR while the structural features and contour preservation have increased 4.96% in MSSIM and 0.70% in β, respectively. As the obtained results shown, the proposed method is able to reduce the speckle noise, to preserve the spatial characteristics and the contour information of the images and it is indicated for noise reduction at noise levels commonly found in ultrasound equipment.

Image Noise Reduction Method Based on Local Correlation

Abstract: A method for reducing image noise includes calculating a first pixel amount of pixels that are similar to each other in a first number neighbor of a center pixel in a motion window, determining whether the first pixel amount of pixels that are similar to each other in the first number neighbor is greater than a first predetermined value, and using a mean of those pixels of the first pixel amount of pixels that are similar to each other in the first number neighbor to restore the center pixel of the motion window if the first pixel amount of pixels is greater than the first predetermined value. The method includes determining whether a second pixel amount of pixels that are similar to the center pixel is greater than a second predetermined value if the first pixel amount of pixels is not greater than the first predetermined value.

A New Image Denoising Framework Based on Bilateral Filter

Abstract: The bilateral filter is a nonlinear filter that does spatial averaging without smoothing edges; it has shown to be an effective image denoising technique in addition to some other applications. There are two main contributions of this paper. First, we provide an empirical study of the optimal parameter selection for the bilateral filter in image denoising applications. Second, we present an extension of the bilateral filter: multi-resolution bilateral filter, where bilateral filtering is applied to low-frequency subbands of a signal decomposed using an orthogonal wavelet transform. Combined with wavelet thresholding, this new image denoising framework turns out to be very effective in eliminating noise in real noisy images. We provide experimental results with both simulated data and real data.