{"title":"What does an aberrated photo tell us about the lens and the scene?","authors":"Huixuan Tang, Kiriakos N. Kutulakos","doi":"10.1109/ICCPhot.2013.6528316","DOIUrl":"https://doi.org/10.1109/ICCPhot.2013.6528316","url":null,"abstract":"We investigate the feasibility of recovering lens properties, scene appearance and depth from a single photo containing optical aberrations and defocus blur. Starting from the ray intersection function of a rotationally-symmetric compound lens and the theory of Seidel aberrations, we obtain three basic results. First, we derive a model for the lens PSF that (1) accounts for defocus and primary Seidel aberrations and (2) describes how light rays are bent by the lens. Second, we show that the problem of inferring depth and aberration coefficients from the blur kernel of just one pixel has three degrees of freedom in general. As such it cannot be solved unambiguously. Third, we show that these degrees of freedom can be eliminated by inferring scaled aberration coefficients and depth from the blur kernel at multiple pixels in a single photo (at least three). These theoretical results suggest that single-photo aberration estimation and depth recovery may indeed be possible, given the recent progress on blur kernel estimation and blind deconvolution.","PeriodicalId":289563,"journal":{"name":"IEEE International Conference on Computational Photography (ICCP)","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128713058","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kenichiro Tanaka, Y. Mukaigawa, Y. Matsushita, Y. Yagi
{"title":"Descattering of transmissive observation using Parallel High-Frequency Illumination","authors":"Kenichiro Tanaka, Y. Mukaigawa, Y. Matsushita, Y. Yagi","doi":"10.1109/ICCPhot.2013.6528300","DOIUrl":"https://doi.org/10.1109/ICCPhot.2013.6528300","url":null,"abstract":"The inner structures of an object can be measured by capturing transmissive images. However, the recorded images of a translucent object tend to be unclear due to strong scattering of light inside the object. In this paper, we propose a descattering approach based on Parallel High-frequency Illumination. We show in this paper that the original high-frequency illumination method and the various extended techniques can be uniformly defined as a separation of overlapped and non-overlapped light rays. Also, we show that transmissive light rays do not overlap each other by constructing a parallel projection/measurement system for performing both illumination and observation. We have developed a measurement system that consists of a camera and projector with telecentric lenses and have evaluated descattering effects by extracting transmissive light rays.","PeriodicalId":289563,"journal":{"name":"IEEE International Conference on Computational Photography (ICCP)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121262990","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A generative focus measure with application to omnifocus imaging","authors":"Avinash Kumar, N. Ahuja","doi":"10.1109/ICCPhot.2013.6528295","DOIUrl":"https://doi.org/10.1109/ICCPhot.2013.6528295","url":null,"abstract":"Given a stack of registered images acquired using a range of focus settings (focal stack images), we propose a new focus measure to identify the most focused image. Although, most of the paper is concerned with the new focus measure, for evaluation purposes, we will present it in the context of an application to generating omnifocus images. An omnifocus image is the composite image in which each pixel is selected form the frame in the stack in which it appears to be in best focus. Conventional focus measures usually maximize some measure of image gradient in a window. They tend to fail when one of the edges of the window lies near the boundary of an intensity edge, or the pixel is near other complex edge patterns. This leads to the misidentification of the focused frame and formation of artifacts in omnifocused image. Our proposed measure does not attempt to identify the focused frame by calculating the degree of defocus, like the gradient based methods. Rather, it hypothesizes that a specific frame is in focus and then validates or rejects this hypothesis by recreating the defocused frames in the vicinity, and comparing them with the observed de-focused frames. This forward generative process leads to correct focus frame selection in regions where typical measures fail. This is because the conventional measures try to identify the focused frame from its distorted version which is the result of a complex convolution process. This involves a backward estimation for a many-to-one transformation. On the other hand, the generation of defocused frames from a hypothesized focused frame is more accurate since it involves applying an operator in the forward direction. We analytically show that under ideal imaging conditions, the proposed focus measure is unimodal in nature. This makes the search for the best focused image unambiguous. We evaluate our focus measure by generating omnifocus images from real focal stack images, and show that it performs better than all the existing focus measures.","PeriodicalId":289563,"journal":{"name":"IEEE International Conference on Computational Photography (ICCP)","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123303220","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
L. Yu, Sai-Kit Yeung, Yu-Wing Tai, Demetri Terzopoulos, T. Chan
{"title":"Outdoor photometric stereo","authors":"L. Yu, Sai-Kit Yeung, Yu-Wing Tai, Demetri Terzopoulos, T. Chan","doi":"10.1109/ICCPHOT.2013.6528306","DOIUrl":"https://doi.org/10.1109/ICCPHOT.2013.6528306","url":null,"abstract":"We introduce a framework for outdoor photometric stereo utilizing natural environmental illumination. Our framework extends beyond existing photometric stereo methods intended for laboratory environments to encompass robust outdoor operation in the real world. In this paper, we motivate our framework, describe the components of its processing pipeline, and assess its performance in synthetic experiments as well as in natural experiments including objects in outdoor environments with complex real-world illuminations.","PeriodicalId":289563,"journal":{"name":"IEEE International Conference on Computational Photography (ICCP)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122074277","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Focal sweep videography with deformable optics","authors":"Daniel Miau, O. Cossairt, S. Nayar","doi":"10.1109/ICCPhot.2013.6528302","DOIUrl":"https://doi.org/10.1109/ICCPhot.2013.6528302","url":null,"abstract":"A number of cameras have been introduced that sweep the focal plane using mechanical motion. However, mechanical motion makes video capture impractical and is unsuitable for long focal length cameras. In this paper, we present a focal sweep telephoto camera that uses a variable focus lens to sweep the focal plane. Our camera requires no mechanical motion and is capable of sweeping the focal plane periodically at high speeds. We use our prototype camera to capture EDOF videos at 20fps, and demonstrate space-time refocusing for scenes with a wide depth range. In addition, we capture periodic focal stacks, and show how they can be used for several interesting applications such as video refocusing and trajectory estimation of moving objects.","PeriodicalId":289563,"journal":{"name":"IEEE International Conference on Computational Photography (ICCP)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123530964","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Transformation guided image completion","authors":"Jia-Bin Huang, J. Kopf, N. Ahuja, S. B. Kang","doi":"10.1109/ICCPhot.2013.6528313","DOIUrl":"https://doi.org/10.1109/ICCPhot.2013.6528313","url":null,"abstract":"In this paper, we describe a new interactive image completion system that allows users to easily specify various forms of mid-level structures in the image. Our system supports the specification of four basic symmetric types: reflection, translation, rotation, and glide. The user inputs are automatically converted into guidance maps that encode possible candidate shifts and, indirectly, local transformations of rotation and scale. These guidance maps are used in conjunction with a color matching cost for image completion. We show that our system is capable of handling a variety of challenging examples.","PeriodicalId":289563,"journal":{"name":"IEEE International Conference on Computational Photography (ICCP)","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121397755","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Unified HDR reconstruction from raw CFA data","authors":"J. Kronander, S. Gustavson, G. Bonnet, J. Unger","doi":"10.1109/ICCPhot.2013.6528315","DOIUrl":"https://doi.org/10.1109/ICCPhot.2013.6528315","url":null,"abstract":"HDR reconstruction from multiple exposures poses several challenges. Previous HDR reconstruction techniques have considered debayering, denoising, resampling (alignment) and exposure fusion in several steps. We instead present a unifying approach, performing HDR assembly directly from raw sensor data in a single processing operation. Our algorithm includes a spatially adaptive HDR reconstruction based on fitting local polynomial approximations to observed sensor data, using a localized likelihood approach incorporating spatially varying sensor noise. We also present a realistic camera noise model adapted to HDR video. The method allows reconstruction to an arbitrary resolution and output mapping. We present an implementation in CUDA and show real-time performance for an experimental 4 Mpixel multi-sensor HDR video system. We further show that our algorithm has clear advantages over state-of-the-art methods, both in terms of flexibility and reconstruction quality.","PeriodicalId":289563,"journal":{"name":"IEEE International Conference on Computational Photography (ICCP)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130008839","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The omnipolar camera: A new approach to stereo immersive capture","authors":"V. Chapdelaine-Couture, S. Roy","doi":"10.1109/ICCPhot.2013.6528311","DOIUrl":"https://doi.org/10.1109/ICCPhot.2013.6528311","url":null,"abstract":"We introduce in this paper a camera setup for stereo immersive (omnistereo) capture. An omnistereo pair of images gives stereo information up to 360 degrees around a central observer. Previous methods to produce omnistereo images assume a static scene in order to stitch together multiple images captured by a stereo camera rotating on a fixed tripod. Our omnipolar camera setup uses a minimum of 3 cameras with fisheye lenses. The multiple epipoles are used as locations to stitch the images together and produce omnistereo images with no horizontal misalignments due to parallax. We show results of using 3 cameras to capture an unconstrained dynamic scene while the camera is travelling. The produced omnistereo videos are formatted to be displayed on a cylindrical screen or dome.","PeriodicalId":289563,"journal":{"name":"IEEE International Conference on Computational Photography (ICCP)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115673501","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Combining the power of Internal and External denoising","authors":"Inbar Mosseri, Maria Zontak, M. Irani","doi":"10.1109/ICCPhot.2013.6528298","DOIUrl":"https://doi.org/10.1109/ICCPhot.2013.6528298","url":null,"abstract":"Image denoising methods can broadly be classified into two types: “Internal Denoising” (denoising an image patch using other noisy patches within the noisy image), and “External Denoising” (denoising a patch using external clean natural image patches). Any such method, whether Internal or External, is typically applied to all image patches. In this paper we show that different image patches inherently have different preferences for Internal or External de-noising. Moreover, and surprisingly, the higher the noise in the image, the stronger the preference for Internal De-noising. We identify and explain the source of this behavior, and show that Internal/External preference of a patch is directly related to its individual Signal-to-Noise-Ratio (“PatchSNR”). Patches with high PatchSNR (e.g., patches on strong edges) benefit much from External Denoising, whereas patches with low PatchSNR (e.g., patches in noisy uniform regions) benefit much more from Internal Denoising. Combining the power of Internal or External denoising selectively for each patch based on its estimated PatchSNR leads to improvement in denoising performance.","PeriodicalId":289563,"journal":{"name":"IEEE International Conference on Computational Photography (ICCP)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132771916","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Simultaneous HDR image reconstruction and denoising for dynamic scenes","authors":"C. Aguerrebere, J. Delon, Y. Gousseau, P. Musé","doi":"10.1109/ICCPhot.2013.6528309","DOIUrl":"https://doi.org/10.1109/ICCPhot.2013.6528309","url":null,"abstract":"High dynamic range (HDR) images are usually generated by combining multiple photographs acquired with different exposure times. This approach, while effective, suffers from various drawbacks. The irradiance estimation is performed by combining, for each pixel, different exposure values at the same spatial position. This estimation scheme does not take advantage of the redundancy present in most images. Moreover, images must be perfectly aligned and objects must be in the exact same position in all frames in order to combine the different exposures. In this work, we propose a new HDR image generation approach that simultaneously copes with these problems and exploits image redundancy to produce a denoised result. A reference image is chosen and a patch-based approach is used to find similar pixels that are then combined for the irradiance estimation. This patch-based approach permits to obtain a denoised result and is robust to image misalignments and object motions. Results show significant improvements in terms of noise reduction over previous HDR image generation techniques, while being robust to motion and changes between the exposures.","PeriodicalId":289563,"journal":{"name":"IEEE International Conference on Computational Photography (ICCP)","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126939471","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}