Search results for "Photograph"
showing 10 items of 364 documents
Unmanned aerial system imagery and photogrammetric canopy height data in area-based estimation of forest variables
2015
In this paper we examine the feasibility of data from unmanned aerial vehicle (UAV)-borne aerial imagery in stand-level forest inventory. As airborne sensor platforms, UAVs offer advantages cost and flexibility over traditional manned aircraft in forest remote sensing applications in small areas, but they lack range and endurance in larger areas. On the other hand, advances in the processing of digital stereo photography make it possible to produce three-dimensional (3D) forest canopy data on the basis of images acquired using simple lightweight digital camera sensors. In this study, an aerial image orthomosaic and 3D photogrammetric canopy height data were derived from the images acquired …
Multitemporal Monitoring of Plant Area Index in the Valencia Rice District with PocketLAI
2016
Leaf area index (LAI) is a key biophysical parameter used to determine foliage cover and crop growth in environmental studies in order to assess crop yield. Frequently, plant canopy analyzers (LAI-2000) and digital cameras for hemispherical photography (DHP) are used for indirect effective plant area index (PAI(eff)) estimates. Nevertheless, these instruments are expensive and have the disadvantages of low portability and maintenance. Recently, a smartphone app called PocketLAI was presented and tested for acquiring PAI(eff) measurements. It was used during an entire rice season for indirect PAI(eff) estimations and for deriving reference high-resolution PAI(eff) maps. Ground PAI(eff) value…
Photography, Production Design, and Editing
2012
The formal features that have made Spanish cinema what it is and the technical processes behind them (camerawork, production design, editing) have passed through the same stages of trial and error, hurdles, crises, and conflicts as has been the case with other national cinemas. The notion of the exceptionalism of Spanish cinema is not supported by evidence, unless by “anomaly” we just mean “cultural specificity.” Cultural specificities there have been, as there are today: the highly idiosyncratic set designs of popular adaptations (of zarzuelas, of literary texts) in the 1920s; the enforced experimentation of the Civil War; the claustrophobic atmosphere of the postwar years; the prolongatio…
Determination of hydroquinone and metal in photographic developer by reversed-phase ion-pair chromatography with amperometric detection
1988
Abstract Sodium 1-heptanesulphonate is used as an ion-pair reagent for the chromatographic separation of the two developing agents on a phenylsilica micro-column, with amperometric detection at an applied potential of + 0.75 V (vs. Ag/AgCl). No pretreatment of the developer is necessary. Linear calibration graphs were obtained in the range 10 −5 -1.5 × 10 −4 M.
Semi-automated evaluation tool for retinal vasculopathy.
2009
The ocular fundus is the only area of human body where vascular system is visible using relatively simple instrumentation. Furthermore, there is medical suggestive evidence of a direct relationship between certain measures of vascular characteristics in the ocular fundus (arteriolar and venular calibers and focal arteriolar narrowing) and cardiovascular diseases. In order to establish such relationship on sound statistical basis a method must be provided to measure the needed values in an easy, yet precise and repeatable way. This paper presents a system to assist physicians in signaling and storing the data associated to signs of vascular deterioration and vascular calibers in non-mydriati…
Improved Statistically Based Retrievals via Spatial-Spectral Data Compression for IASI Data
2019
In this paper, we analyze the effect of spatial and spectral compression on the performance of statistically based retrieval. Although the quality of the information is not com- pletely preserved during the coding process, experiments reveal that a certain amount of compression may yield a positive impact on the accuracy of retrievals. We unveil two strategies, both with interesting benefits: either to apply a very high compression, which still maintains the same retrieval performance as that obtained for uncompressed data; or to apply a moderate to high compression, which improves the performance. As a second contribution of this paper, we focus on the origins of these benefits. On the one…
High-resolution far-field integral-imaging camera by double snapshot
2012
In multi-view three-dimensional imaging, to capture the elemental images of distant objects, the use of a field-like lens that projects the reference plane onto the microlens array is necessary. In this case, the spatial resolution of reconstructed images is equal to the spatial density of microlenses in the array. In this paper we report a simple method, based on the realization of double snapshots, to double the 2D pixel density of reconstructed scenes. Experiments are reported to support the proposed approach.
A Dual Taxonomy for Defects in Digitized Historical Photos
2009
Old photos may be affected by several types of defects. Manual restorers use their own taxonomy to classify damages by which a photo is affected, in order to apply the proper restoration techniques for a specific defect. Once a photo is digitally acquired, defects become part of the image, and their aspect change. This paper wants to be a first attempt to correlate real defects of printed photos, and digital defects of their digitized versions. A dual taxonomy is proposed, for real and digital defects, and used to classify an image dataset, for a posteriori comparative study. Furthermore, a set of digital features is analyzed for digitized images, to identify which of them could be useful f…
Guest Editorial Three-Dimensional Displays and Visualization
2010
THREE-DIMENSIONAL (3D) imaging and display is a natural concept for humans as it is a common vision attribute of our binocular vision, perception, and brain processing. However, until recently, our experiences have been mainly limited to the technologically inferior two-dimensional (2D) as evidenced from widespread use of 2D photography, cinema, and liquid crystal or LED-display for television, computer displays, etc.
The Multimodality of Digital Longform Journalism
2016
Digital longform journalism has recently attracted increased attention among both academics and professionals. This study contributes to the growing body of research by dissecting the multimodal structure of digital longform journalism, that is, how the emerging genre combines written language, photography, short videos, maps and other graphical elements, and joins them together into a seamless narrative using subtle transitions. The data consist of 12 longform articles published in 2012–2013, which have been annotated for their visual and verbal content, their underlying principle of organization and the transitions that hold between them. The annotation is stored into a digital corpus, wh…