Channel (digital image)

About: Channel (digital image) is a research topic. Over the lifetime, 7211 publications have been published within this topic receiving 69974 citations.

Chromatic aberration correction

Abstract: A chromatic aberration (CA) correction technique is presented that substantially removes CA from an image captured by a digital camera. In general, the effects of any in-camera sharpening are reversed by applying a blurring kernel. The image is then super-sampled to approximate its state prior to the application of in-camera sampling. One of the color channels is designated as a reference channel, and an objective function is established for each of the non-reference channels. The reference color channel is assumed to be CA-free, while the objective functions are used to compute the unknown CA parameters for each non-reference channel. These sets are used in a CA removal function to substantially remove the CA associated with each of the non-reference channels. The image is then sampled to return it to its original resolution, and a sharpening filter is applied if needed to undo the effects of the previously applied blurring kernel.

Stereo Picture Quality Estimation Based on a Multiple Channel HVS Model

Abstract: The understanding and estimation of stereo images are very important. There are many models of human visual system for planar image. It is blank for stereo image. An estimation of stereo image quality is proposed based on a multiple channel human visual system (HVS) for use in image compression .The model is based on a plane model, but has some modifications that make it is more suitable to stereo image pair. Difference as the important characteristic of stereo images is used to evaluate the quality of stereo image.

Underwater image restoration via depth map and illumination estimation based on a single image

Abstract: For the enhancement process of underwater images taken in various water types, previous methods employ the simple image formation model, thus obtaining poor restoration results. Recently, a revised underwater image formation model (i.e., the Akkaynak-Treibitz model) has shown better robustness in underwater image restoration, but has drawn little attention due to its complexity. Herein, we develop a dehazing method utilizing the revised model, which depends on the scene depth map and a color correction method to eliminate color distortion. Specifically, we first design an underwater image depth estimation method to create the depth map. Subsequently, according to the depth value of each pixel, the backscatter is estimated and removed by the channel based on the revised model. Furthermore, we propose a color correction approach to adjust the global color distribution of the image automatically. Our method only uses a single underwater image as input to eliminate lightwave absorption and scattering influence. Compared with state-of-the-art methods, both subjective and objective experimental results show that our approach can be applied to various real-world underwater scenes and has better contrast and color.

Acquisition of multiple image stacks with a confocal laser scanning microscope

Abstract: Image acquisition at high magnification is inevitably correlated with a limited view over the entire tissue section. To overcome this limitation we designed software for multiple image-stack acquisition (3D-MISA) in confocal laser scanning microscopy (CLSM). The system consists of a 4 channel Leica CLSM equipped with a high resolution z- scanning stage mounted on a xy-monitorized stage. The 3D- MISA software is implemented into the microscope scanning software and uses the microscope settings for the movements of the xy-stage. It allows storage and recall of 70 xyz- positions and the automatic 3D-scanning of image arrays between selected xyz-coordinates. The number of images within one array is limited only by the amount of disk space or memory available. Although for most applications the accuracy of the xy-scanning stage is sufficient for a precise alignment of tiled views, the software provides the possibility of an adjustable overlap between two image stacks by shifting the moving steps of the xy-scanning stage. After scanning a tiled image gallery of the extended focus-images of each channel will be displayed on a graphic monitor. In addition, a tiled image gallery of individual focal planes can be created. In summary, the 3D-MISA allows 3D-image acquisition of coherent regions in combination with high resolution of single images.

Apparatus based on image for detecting heart rate activity and method thereof

Abstract: An apparatus and method based on image for detecting heart rate activity is provided. The method includes: obtaining a plurality of color images; based on a complexion target condition, defining a target region; performing color composition analysis on the target region to obtain red channel signal, green channel signal and blue channel signal, respectively; performing independent component analysis on separate red, green and blue channel signals to obtain separate first independent component signal, second independent component signal and third independent component signal; performing frequency domain transform, signal energy computation and signal optimization processes on separate first, second and third independent component signals to obtain a filter signal, comparing filter signal based on a pre-set condition to determine if target region belonging to a human, and performing a physiological information analysis.