Objective methods for assessing perceptual image quality traditionally attempted to quantify the visibility of errors (differences) between a distorted image and a reference image using a variety of known properties of the human visual system. Under the assumption that human visual perception is highly adapted for extracting structural information from a scene, we introduce an alternative complementary framework for quality assessment based on the degradation of structural information. As a specific example of this concept, we develop a structural similarity index and demonstrate its promise through a set of intuitive examples, as well as comparison to both subjective ratings and state-of-the-art objective methods on a database of images compressed with JPEG and JPEG2000. A MATLAB implementation of the proposed algorithm is available online at http://www.cns.nyu.edu//spl sim/lcv/ssim/.

/pdf/image-quality-assessment-from-error-visibility-to-structural-1rlwcqe34t.pdf

Image quality assessment: from error visibility to structural similarity

Introduction to a Transient World. Fourier Kingdom. Discrete Revolution. Time Meets Frequency. Frames. Wavelet Zoom. Wavelet Bases. Wavelet Packet and Local Cosine Bases. An Approximation Tour. Estimations are Approximations. Transform Coding. Appendix A: Mathematical Complements. Appendix B: Software Toolboxes.

http://ahvazdownload.persiangig.com/document/article/39.pdf

A wavelet tour of signal processing

We investigate conditional adversarial networks as a general-purpose solution to image-to-image translation problems. These networks not only learn the mapping from input image to output image, but also learn a loss function to train this mapping. This makes it possible to apply the same generic approach to problems that traditionally would require very different loss formulations. We demonstrate that this approach is effective at synthesizing photos from label maps, reconstructing objects from edge maps, and colorizing images, among other tasks. Moreover, since the release of the pix2pix software associated with this paper, hundreds of twitter users have posted their own artistic experiments using our system. As a community, we no longer hand-engineer our mapping functions, and this work suggests we can achieve reasonable results without handengineering our loss functions either.

/pdf/image-to-image-translation-with-conditional-adversarial-5058t24et2.pdf

Image-to-Image Translation with Conditional Adversarial Networks

We investigate conditional adversarial networks as a general-purpose solution to image-to-image translation problems. These networks not only learn the mapping from input image to output image, but also learn a loss function to train this mapping. This makes it possible to apply the same generic approach to problems that traditionally would require very different loss formulations. We demonstrate that this approach is effective at synthesizing photos from label maps, reconstructing objects from edge maps, and colorizing images, among other tasks. Indeed, since the release of the pix2pix software associated with this paper, a large number of internet users (many of them artists) have posted their own experiments with our system, further demonstrating its wide applicability and ease of adoption without the need for parameter tweaking. As a community, we no longer hand-engineer our mapping functions, and this work suggests we can achieve reasonable results without hand-engineering our loss functions either.

Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

Phd by thesis

Visual quality assessment of stereoscopic/3D images and videos has become an increasingly important and active field of research with the rapid growth in the quantity of stereoscopic/3D content created by the cinema, television, and entertainment industries. However, due to the diversity of stereoscopic/3D display technology and the complexity of human 3D perception, understanding the quality of experience (QoE) of stereoscopic/3D image and video is a difficult and multidisciplinary problem. Objective visual quality assessment attempts to quantify this subjective perception of visual QoE, utilizing tools from engineering, visual science, and psychology. In this chapter, first we discuss the challenges and difficulties one may face while trying to design and develop an effective objective quality assessment (QA) algorithm for stereoscopic images. This discussion is limited to “quality” where the stimulus being perceived is affected by some kind of distortions. In contrast to the success of a variety of objective QA algorithms for 2D images and videos, the field of stereoscopic image and video QA has been less successful in finding widely adopted quality measures. Most objective stereoscopic QA algorithms can be regarded as extensions of 2D QA algorithms, while few of them consider some aspects of depth perception and utilize either computed or measured depth/disparity information from the stereo pairs. We examine and analyze these stereoscopic QA algorithms, while focusing mainly on advances in exploiting natural scene statistics (NSS) and human visual system models in the design of stereoscopic QA algorithms. We also discuss recent work conducted on evaluating visual discomfort and fatigue when viewing stereoscopic images and videos—the more comprehensive “quality-of-experience” evaluation. Finally, we conclude the chapter with a discussion of possible future directions that the field of stereoscopic image and video QA may take. Our summary focuses on gaining a better understanding of depth/disparity sensation, using accurate and robust statistical models of natural stereo pairs, and performing a thorough analysis of various factors affecting the perception of stereoscopic distortions.

Visual Quality Assessment of Stereoscopic Image and Video: Challenges, Advances, and Future Trends

Microprocessor-based recognition of handprinted characters from a tablet input

An algorithm is presented to automatically detect near surface ice layers in images from the Shallow Subsurface Radar (SHARAD) on NASA's Mars Reconnaissance Orbiter. Mars' ice-rich Northern Polar Layered Deposits (NPLD) represents an extensive geologic record of climate history. Identifying ice layers in cross-sectional images leads to understanding the three-dimensional structure of ice layers. Scientists have manually identified layers in large data volumes, but the automated algorithm will allow studying more images from over a thousand orbital crossings. A unique coordinate transformation, based upon the surface reflection, makes subsequent filtering and detection more effective on near surface layers. Results show promising capabilities for automatically detecting ice layers on Mars.

/pdf/automated-detection-of-near-surface-martian-ice-layers-in-50heyjdqwx.pdf

Automated detection of near surface Martian ice layers in orbital radar data

We describe a study aimed towards increasing our understanding of the perception of distorted stereoscopic 3D images, by analyzing subjects' performance in locating local distortions in stereoscopically viewed images. Nineteen subjects were recruited for this study. The results indicated that contrast and range variations are correlated with the conspicuity of some distortions, but not others.

/pdf/study-on-distortion-conspicuity-in-stereoscopically-viewed-2m2zv6777f.pdf

Study on distortion conspicuity in stereoscopically viewed 3D images

Multicolor fluorescence in situ hybridization (M-FISH) techniques provide color karyotyping that allows simultaneous analysis of numerical and structural abnormalities of whole human chromosomes. Chromosomes are stained combinatorially in M-FISH. By analyzing the intensity combinations of each pixel, all chromosome pixels in an image are classified. Due to the overlap of excitation and emission spectra and the broad sensitivity of image sensors, the obtained images contain crosstalk between the color channels. The crosstalk complicates both visual and automatic image analysis and may eventually affect the classification accuracy in M-FISH. The removal of crosstalk is possible by finding the color compensation matrix, which quantifies the color spillover between channels. However, there exists no simple method of finding the color compensation matrix from multichannel fluorescence images whose specimens are combinatorially hybridized. In this paper, we present a method of calculating the color compensation matrix for multichannel fluorescence images whose specimens are combinatorially stained.

/pdf/color-compensation-of-multicolor-fish-images-4coqkmgxu0.pdf

Alan C. Bovik

Papers

Visual Quality Assessment of Stereoscopic Image and Video: Challenges, Advances, and Future Trends

Microprocessor-based recognition of handprinted characters from a tablet input

Automated detection of near surface Martian ice layers in orbital radar data

Study on distortion conspicuity in stereoscopically viewed 3D images

Color Compensation of Multicolor FISH Images