Binocular Stereoscopic Images Research Articles

Adaptive Viewpoint Feature Enhancement-Based Binocular Stereoscopic Image Saliency Detection

Modeling 3D visual saliency has received great attention due to the development of emerging 3D display technologies. Traditional methods relying on low-level features may not be efficient in interpreting 3D visual content from high-level semantic perspective. Despite numerous efforts dedicated to this area, existing 3D visual saliency detection methods do not necessarily excel in exploring the stereoscopic image saliency driven by the intra-view and inter-view dependencies among left and right views. In this paper, we propose a visual saliency detection method for stereoscopic images grounded on adaptive viewpoint feature enhancement via binocular vision. More specifically, the correlation among left and right views is investigated through a delicately designed binocular stereoscopic saliency feature aggregation module, enabling the generation of more representative saliency features towards binocular vision. Subsequently, to further aggregate the saliency features in multiple scales, we design a progressive attention-based saliency feature pyramid extraction module to effectively integrate the features from top-level to down-level based on the network hierarchy mechanism. The saliency maps are ultimately produced for stereoscopic images by evaluating the obtained saliency features. In addition, we create a stereoscopic image saliency dataset (SIS-3D) that includes 1086 stereoscopic image pairs with various content and their corresponding human eye fixation annotations, aiming to further facilitate the research on visual saliency detection for stereoscopic images. Extensive experiments demonstrate that our proposed method improves CC by an average of 4.02% compared to representative counterparts on the newly built saliency dataset and another publicly available dataset.

Ultra-sensitive nanometric flat laser prints for binocular stereoscopic image

Two-dimensional (2D) transition metal dichalcogenides (TMDs) with tantalizing layer-dependent electronic and optical properties have emerged as a paradigm for integrated flat opto-electronic devices, but their widespread applications are hampered by challenges in deterministic fabrication with demanded shapes and thicknesses, as well as light field manipulation in such atomic-thick layers with negligible thicknesses compared to the wavelength. Here we demonstrate ultra-sensitive light field manipulation in full visible ranges based on MoS2 laser prints exfoliated with nanometric precisions. The nontrivial interfacial phase shifts stemming from the unique dispersion of MoS2 layers integrated on the metallic substrate empower an ultra-sensitive resonance manipulation up to 13.95 nm per MoS2 layer across the entire visible bands, which is up to one-order-of-magnitude larger than their counterparts. The interlayer van der Waals interactions and the anisotropic thermal conductivity of layered MoS2 films endow a laser exfoliation method for on-demand patterning MoS2 with atomic thickness precision and subwavelength feature sizes. With this, nanometric flat color prints and further amplitude-modulated diffractive components for binocular stereoscopic images can be realized in a facile and lithography-free fashion. Our results with demonstrated practicality unlock the potentials of, and pave the way for, widespread applications of emerging 2D flat optics.

Subjective and Objective Quality Assessment for Stereoscopic Image Retargeting

Binocular stereoscopic image retargeting (SIR) aims to adjust 3D images into target aspect ratios. In recent years, various SIR methods have been proposed, but there are few researches on visual quality assessment. As a consequence, we construct a benchmark stereoscopic image retargeting quality assessment database (NBU-SIRQA), which contains 720 stereoscopic retargeted images generated by eight representative SIR operators. Subjective test is conducted to obtain the mean opinion score (MOS) for each stereoscopic retargeted image. Additionally, we propose an objective SIRQA metric based on grid deformation and information loss (GDIL). The main idea of GDIL is to decompose the SIR operator into two transformations: monocular image retargeting transformation and viewpoint transformation. In each transformation, grid deformation and information loss are extracted simultaneously to represent image quality and 3D perception quality. Experimental results validated on our established NBU-SIRQA database show the superiority of our metric in measuring the quality of stereoscopic retargeted images over the existing approaches.

Stereoscopic Image Feature Indexing Based on Hybrid Grid Multiple Suffix Tree and Hierarchical Clustering

In order to achieve content-based binocular stereoscopic image or video retrieval efficiently, a feature indexing algorithm based on hybrid grid multiple suffix tree and hierarchical clustering is proposed. With the RGB-D image model, the shape features of depth map obtained from the matching of binocular stereoscopic left image and right image and the color features of left image are extracted respectively. The features are quantified and hashed, and the optimized underlying features are sorted as leaf nodes of hierarchical indexing. Then the shape and color feature values of leaf nodes are mapped to the two-dimensional coordinates, and the 2D feature points are put into different grid hash areas respectively by clustering and labeled with multiple suffix tree. Furthermore, to construct the global index, a pointer to an array of clustering grid center point is defined according to the computation of grid area feature values. The experimental results show that compared to the double grid suffix tree and typical stereoscopic image feature indexing structure, the proposed algorithm can effectively reduce the indexing construction complexity While maintaining high recall, it can also greatly improve the query efficiency, which can better realize the feature indexing of binocular stereoscopic images or videos.

Stereoscopic color transfer and disparity remapping based on selected object

Color transfer has been a hot research issue in the field of image processing and computer vision in recent years. The main purpose is to transfer the color of a target image to source image so that the source image has the same or similar color features with the target image. In practical applications for the color transfer of binocular stereoscopic images, the user may only need to transfer the color of the selected object while keeping the background color unchanged. For this purpose, a color transfer method based on the selected object is proposed in this paper. In the method, by assigning the object of the image by user, the accurate object is segmented via graph cut, and the probability density curves of color distribution between the selected object and the target image are matched to accomplish the color transfer. In order to enhance the viewing experience provided for the user, a non-linear disparity optimization is performed after the color transfer operation. According to the histogram feature of disparity map, the disparity mapping function is calculated, and the target disparity is obtained to enhance the depth sensation of the selected object. The experimental results demonstrate that the combination of stereoscopic color transfer and disparity remapping effectively enhances the stereoscopic viewing experience.

Experimental verification of accommodation-convergence conflict in viewing integral photography

We experimentally verified the depth perception and accommodation-convergence conflict in viewing integral photography. For comparison, the same measurements were performed with binocular stereoscopic images and real objects. First, the depth perception in viewing an integral three-dimensional (3D) target was measured at three display resolutions: 153, 229, and 458 ppi. The results showed that the depth perception was dependent on the display resolution. The results were also evaluated in a statistical test at a significance level of 5%. The results showed that the recognized depth perception ranges were 180, 240, and 330 mm when the display resolutions were 153, 229, and 458 ppi, respectively. The results were also analyzed in terms of image resolution. This suggested that depth perception occurred at over 1.0 cpd. The accommodation and convergence responses in viewing an integral 3D target displayed on a 3D display with 458 ppi were measured using PowerRef 3. The experimental results were evaluated with a multiple comparison test. It was found that 6 of the 10 observers did not have an accommodation-convergence conflict when viewing the integral 3D target inside and outside the depth of field. In conclusion, integral photography can provide a natural 3D image that looks like a real object.

Measurement of static convergence and accommodation responses to images of integral photography and binocular stereoscopy.

Static convergence and accommodation responses were measured by comparing integral photography images, binocular stereoscopic images, and real objects in a measurement range from 450 to 900 mm. The experimental results were evaluated with a multiple comparison test. It was found that six of the ten observers did not have an accommodation-convergence conflict in viewing integral photography in the range. Moreover, the required resolution was found to be 0.7 or more and less than 1.4 cycles per degree for inducing accommodation. In conclusion, integral photography can provide a natural 3D image that looks like a real object.

Content-aware disparity adjustment for different stereo displays

In this paper, we present an effective disparity mapping method for binocular stereoscopic image. It is inspired by the observation that its displayed depth would change, when a stereoscopic image is displayed on different size screens. The phenomenon may bring an uncomfortable experience for viewers. To make a comfortable stereoscopic image for viewers, moreover to adapt a stereoscopic image to a target display screen, we propose a content-aware disparity adjustment method. Firstly, the disparity mapping is established to control and retarget the depth of a stereoscopic scene. Then, the relationship between the disparity editing and image content editing is established to guide the proposed warping model. At last, to implement the disparity mapping operator, we propose a content-aware stereoscopic mesh warping model, which can simultaneously avoid the salient region distortion and adjust disparity to a target range by establishing the relationship. Experimental results show that the proposed method can effectively adjust disparity of stereoscopic image, which not only avoids the salient region distortion and adjusts disparity to a target range.

11-16 両眼融合立体画像の解像度低下に伴う調節応答特性(第11部門 ヒューマンインフォメーション(視覚特性および映像・画像評価))

11-16 両眼融合立体画像の解像度低下に伴う調節応答特性(第11部門 ヒューマンインフォメーション(視覚特性および映像・画像評価))

Perceived depth change by decreasing visual acuity in a dominant eye on binocular stereoscopic imaging

Perceived depth change by decreasing visual acuity in a dominant eye on binocular stereoscopic imaging

Stereoscopic imaging using folded lineardual-energy x-ray detectors

A binocular stereoscopic x-ray imaging technique basedon a theory specifically developed for a single x-ray source anda pair of folded linear dual-energy x-ray detector arrays ispresented. The theoretical analysis is discussed in terms of anideal x-ray source and x-ray detectors, and has formed the basisfor the development of an experimental system. The resultantimages may be used for both visual inspection and for theextraction of three-dimensional coordinate information.

Dynamic stereoscopic X-ray imaging

Abstract A multiple view binocular stereoscopic X-ray imaging technique developed as a part of a feasibility study for a security screening application is presented. The experimental system utilises a single X-ray source and a multiple view line-scan camera incorporating an X-ray image intensifier. This set up is used to simulate coplanar configurations of discrete linear X-ray detector arrays. A number of perspective images (typically 6–16) are produced during a single linear translation of the object under inspection. A sequential display of the images produces linear motion parallax in the display. Further work enabled motion parallax to be combined with binocular parallax [NDT&E Int 29 (1996) 27] to produce dynamic binocular stereoscopic images. The perspective images may also be used for the extraction of three-dimensional coordinate information. The results produced by an experimental system are presented together with a theoretical discussion.

Design of a stereoscopic X-ray imaging system using a single X-ray source

The design of a prototype binocular stereoscopic X-ray imaging system for a security screening application is presented. This is based on an innovative technique [Evans JPO, Robinson M, Godber SX. A new stereoscopic imaging technique using a single X-ray source: theoretical analysis. NDT&E International 1996;29(1):27–35] utilising a single X-ray source and a pair of linear X-ray detector arrays. The image data is collected whilst the object under inspection is linearly translated past the X-ray detectors. The machine constructed enables approximately one cubic metre of object space to be imaged in five seconds. The resultant images may also be used for the extraction of three-dimensional coordinate information.

Evaluation of stereoscopic picture quality with CFF.

The method of binocular stereoscopic imaging has attracted attention as a simple and technically feasible means of three-dimensional (3-D) display. It has been said, however, that the binocular picture system is more fatiguing to view than a conventional two-dimensional picture, much as the current television picture. The main objective of this paper is to evaluate quantitatively fatigue caused by binocular stereoscopic picture viewing, to clarify the basic characteristics of this type of picture. Various measurement methods of fatigue have been proposed, and that using the critical flicker frequency (CFF) has found wide use in measurement of mental fatigue and is easy to make. Actual measurement in this study used the CFF value obtained in a descending series of the method of limits, normalized to the value at the start of measurement for each observer, and the CFFs of all observers then averaged. It was found that the measurements produced stable and highly accurate results. CFFs of the observers of a current television picture and a binocular stereoscopic television picture were measured. It was found that the conventional television did not cause a statistically significant decrease in CFF--even over 1 h of viewing--but that the stereoscopic television did cause a significant CFF decrease within 30 min. It was also found that the CFF decreases are related to a subjective feeling of fatigue. From these results, it was concluded that CFF is an effective measure for objectively measuring the fatigue of television observers, including observers of binocular stereoscopic television. Also, the binocular stereoscopic television produced higher fatigue in observers than did the conventional television picture, but it was found that with respect to CFF viewing of around 30 min was allowable.

A new stereoscopic X-ray imaging technique using a single X-ray source: theoretical analysis

A binocular stereoscopic X-ray imaging technique is presented which can be used for both visual inspection by human observers and also for the extraction of three-dimensional coordinate information. The concept of implementing a stereoscopic X-ray imaging system to solve the problem of image interpretation is not new in itself. However, what is innovative in this research is the stereoscopic imaging technique developed. This is based on a rigorous design theory specifically developed for a single X-ray source and a pair of linear X-ray detector arrays.

特集 次世代画像技術 立体画像における大きさの歪みと撮像条件の関係

In the perception of binocular stereoscopic images, the Pupper Theater Effect has been pointed out as a problem of size distortion. In this paper, we discuss the effect of pick-up conditions on this problem, especially the effect of a background.(1) Subjective evaluation tests indicate that a beckground (hallway image) largely affects the perceived size of an object (a manneqin standing in the hallway). They also show that the closer an object is perceived, the smaller the object is perceived.(2) The effect caused by variation both of focal length of lenses and of interaxial distance between the lenses is examined. The Puppet Theater Effect is more enhanced when the sensation of background depth caused by binocular disparity is dominant rather than when that caused the perspective of a lens used in shooting is dominant.

Accommodation Response to Binocular Stereoscopic TV Images and Their Viewing Conditions

The accommodation response of subjects viewing binocular stereoscopic TV images was measured with an objective infrared optometer. It was found that the subjects' eyes showed clear response corresponding to variation of the left-right (L-R) image separation when this was relatively small, and it saturated when the separation was larger The amplitude of the response change depended mainly on the amount of L-R image separation. From these results suitable viewing conditions were determined and are discussed in this article

Synthesis of an autostereoscopic 3-D image from binocular stereoscopic images

Three-dimensional displays can be classified into binocular displays and autostereoscopic displays. In this paper, techniques for synthesizing an autostereoscopic image from binocular ones are presented. Intermediate- viewing-angle images are first synthesized from binocular pictures by linear interpolation between corresponding points upon those pictures. The autostereoscopic spatial image is then obtained by integrating many intermediate-viewing-angle images. An optical system for performing the interpolation all at once is proposed. Experiments and computer simulations are performed for line drawings and continuous-tone pictures.