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| | High dynamic range imaging - Wikipedia, the free encyclopedia |
 | | The use of high dynamic range imaging in computer graphics has been pioneered by Paul Debevec. | | | Gregory Ward is widely considered to be the founder of the file format for high dynamic range imaging. | | | High dynamic range rendering (rendering virtual scenes using high dynamic range lighting calculation, notably in computer games) |
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http://en.wikipedia.org/wiki/High_dynamic_range_imaging
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| | High dynamic range imaging - Wikipedia, the free encyclopedia |
| | The use of high dynamic range imaging in computer graphics has been pioneered by Paul Debevec. | | | Gregory Ward is widely considered to be the founder of the file format for high dynamic range imaging. | | | High dynamic range rendering (rendering virtual scenes using high dynamic range lighting calculation, notably in computer games) |
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http://en.wikipedia.org/wiki/High_dynamic_range_imaging
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| | High dynamic range rendering - Wikipedia, the free encyclopedia |
| | High dynamic range rendering (HDRR or HDR Rendering) is the rendering of 3D computer graphics scenes by using lighting calculations done with a high dynamic range. | | | The use of high dynamic range imaging (HDRI) in computer graphics has been pioneered by Greg Ward in 1985 with his Radiance rendering and lighting simulation software. | | | Now if there's a computer monitor displaying this web page, the dynamic range would be high. |
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http://en.wikipedia.org/wiki/High_dynamic_range_rendering
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| | Encoding |
| | Its dynamic range of 3.8 orders of magnitude is marginal for HDR work, and it is not well-known to the computer graphics community, as there has never been a publication about it other than the source code sitting in Leffler’s TIFF library. | | | The dynamic range is given as orders of magnitude, or the 10-based logarithm of the maximum representable value over the minimum value. | | | Meanwhile, the low end is impoverished in such a way that the effective dynamic range of this format is only about 3.5 orders of magnitude – not really adequate from human perception standpoint, and too limited for light probes and HDR environment mapping. |
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http://www.anyhere.com/gward/hdrenc/hdr_encodings.html
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| | The GSMT Book: Chapter 4, Section 4.7.6.1 |
| | High dynamic range imagery of bright sources will often be limited by speckle structure in the uncorrected halo of the bright source rather than by its photon noise, particularly if coronagraphy or nulling is employed to reduce the amplitude of the diffracted component. | | | In high dynamic range imaging (HDRI) applications, employing coronagraphy or nulling to suppress the coherent diffraction core results in the detection of the faintest sources usually being limited by speckle structure in the image, rather than by the photon noise. | | | AO support high dynamic range imaging by improving the concentration of flux for an unresolved faint source (proportional to S, the Strehl ratio), and by reducing the amplitude of the noncoherent seeing halo (proportional to (1-S)). |
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http://www.aura-nio.noao.edu/book/ch4/4_7_6_1.html
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| | 79784.001228&ELEMENT_SET=DECL |
| | The computed high dynamic range image in the frame memory 407 is converted to an analog signal by a digital-to-analog converter 408, which provides the analog signal to a video output part 412. | | | The high dynamic range image data, which is stored in the output image memory 7, has radiance values proportional to corresponding radiance values of the scene. | | | and provides corresponding pixel values to an image processor 4, which is coupled to a response function memory 6 and an exposure pattern memory 5 and which provides high dynamic range image data to an output image memory 7. |
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http://www.wipo.int/cgi-pct/guest/getbykey5?KEY=00/79784.001228&ELEMENT_SET=DECL
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| | Talk:High dynamic range imaging - Wikipedia, the free encyclopedia |
| | Eventually, a common parent article on HDRI and HDRR named just HDR may be created to which topics which might concern both HDR photo imaging and virtual scene rendering, which is the basic explanation of highy dynamic range and a deeper discussion about displaying a higher dynamic range. | | | Given High dynamic range imaging refers to broader range of fields, I found it would be more appropriate to merge contents from High dynamic range rendering to this page. | | | Given this case, I think it's appropriate to say that HDRI is a photography related subject while HDRR is a computer graphic related subject. |
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http://en.wikipedia.org/wiki/Talk:High_dynamic_range_imaging
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| | A new approach to dynamic range: Digital Photography Review |
| | The work of a professor at Columbia University has lead to the invention of a new approach to dynamic range on CCD's. | | | In their work, the scientists produced images comparable to those produced by a 12-bit digital camera, which has a range of 4,096 brightness levels, even though the imaging system they used had a detector that yields only 8-bits, or 256 brightness levels. | | | Nayar explains that in a conventional imaging chip on a digital camera, for example, all of the light-collecting "pixels'' are equal in the way they collect light, while in the new technology neighboring pixels are exposed differently. |
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http://www.dpreview.com/news/0009/00090702columbiadynrange.asp
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| | Directions in High Dynamic Range Imaging |
| | Since this is an analog technology, the dynamic range depends strongly on the input signal and ambient illumination. | | | With the advancement of computer graphics and computer vision, the issue of extended dynamic range has emerged as a research topic in the late 1980s, even though the displays at the time have by far not even reached the capability to show 8 bits per color channel. | | | In discussing image output technologies, the issues of dynamic range, an analog concept, and bit depth, a digital concept, are extremely important. |
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http://www.cs.yorku.ca/~av/HDR_report.htm
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| | 83773.031009&ELEMENT_SET=DECL |
| | An additional approach to high dynamic range imaging is based on a modification of the conventional charge coupled device (CCD) array. | | | The location of the third image portion is typically determined by interpolating or extrapolating the motion of the object of interest based on the locations of the first and second image portions-for example, by computing an optical flow vector based on the locations of the first and second image portions. | | | For example, if the objects of interest appear underexposed or overexposed, the algorithm computes an adjustment factor by dividing the optimum brightness of the imager by the average brightness of the relevant pixels representing the objects of interest. |
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http://www.wipo.int/cgi-pct/guest/getbykey5?KEY=03/83773.031009&ELEMENT_SET=DECL
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| | Director's Pool - High Dynamic Range Images |
| | We propose to develop new display algorithms for high dynamic range scenes based on advanced psychophysical models of visual adaptation. | | | To develop our display algorithms we will need to integrate the experimental results found in the psychophysics literature into a comprehensive, computationally tractable, and practical model of vision that can be applied to the dynamic range problem. | | | Finally because we want these images to be accurate visual simulations, we intend to conduct experimental comparisons between the images and real high dynamic range scenes to assess the visual fidelity of the images both in terms of the quality of their appearance and in terms of quantitative measures of visual performance. |
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http://www.cs.brown.edu/stc/resea/director/research_dp1.html
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| | Photoshop CS2 HDR |
| | In many ways, Photoshop CS2's HDR function is the holy grail of dynamic range. | | | The above window will result, showing you a merged version of the files, along with thumbnails on the left, each one showing the additional dynamic range above and below a mid-point that it is adding to the final 32 bit image. | | | Dynamic range though is one of the limitations that hasn't yielded much over the years to technology's inexorable advances. |
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http://www.luminous-landscape.com/tutorials/hdr.shtml
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| | idw - High Dynamic Range Imaging: Next Generation Digital Photography and Cinema |
| | To overcome this problem, we have developed at the MPI Informatik High Dynamic Range (HDR)video compression algorithm that can store complete color information that is visible to the human eye. | | | Extended dynamic range cameras for professional digital cinamatography, such Dalsa's Origin, have been developed. | | | Though most of the digital cameras and displays can capture or show 2-3 orders of magnitude (dynamic range 1:100 - 1:1000, 40-60 dB), the next generation monitors and cameras start to operate at the sensitivity levels and dynamic range of the human eye. |
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http://www.idw-online.de/pages/de/news149909
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| | AHDRIA and High Dynamic Range Imaging |
| | Gradient Domain High Dynamic Range Compression A "Results" page for Fattal, Lischinski and Werman's paper, Gradient Domain HDR Compression; includes HDRI files, algorithm comparisons, and many of the standard benchmark images. | | | High Dynamic Range (HDR) imaging is the process of taking "photographs" (usually referred to as HDR images) from real-life scenes with a sensitivity and range of light far beyond what normal cameras are capable of capturing. | | | The most common method for producing HDR images is to capture a single scene over a range of exposure levels (say, 3-15) and then mathematically combine this collection of low dynamic range (LDR) images into a single HDR image. |
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http://www2.cs.uh.edu/~somalley/hdri_images.html
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| | NVIDIA SDK Code Sample Videos |
| | This example demonstrates how to implement simple high-dynamic range rendering in OpenGL on both GeForce FX and GeForce 6 series GPUs. | | | The high dynamic range comes from the lighting passes being accumulated using fp16 blending into a floating point render target, after which tone mapping and a bloom effect are done using fp16 filtering to get the HDR results into the displayable 0..1 range. | | | The cloth vertex positions are computed through several pixel shaders and saved into a texture. |
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http://download.developer.nvidia.com/developer/SDK/Individual_Samples/samples_video.html
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| | Imaging On-Line Store |
| | The absence of a well-calibrated high dynamic range color image database of natural scenes is an impediment to developing such rendering algorithms for digital photography. | | | This suggests that future high dynamic range rendering algorithms need to account jointly for local color adaptation and local illumination level. | | | First, we discuss how the image dynamic range is affected by three main components in the imaging pipeline: the optics, the sensor and the color transformation. |
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http://www.imaging.org/store/epub.cfm?abstrid=8448
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| | Graphics file format summary - Wikipedia, the free encyclopedia |
| | OpenEXR is the Open Source high dynamic-range (HDR) file format developed by Industrial Light and Magic for advanced imaging in movie production. | | | It's commonly considered the actual "state-of-the-art" lossy format for photographic imaging, however its support in modern systems is still weak due to heavy requirements for hardware and many patents for software. | | | Animation format using datastreams similar to those of PNG and JPEG, originally designed to replace the use of animated GIF on the web. |
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http://www.sciencedaily.com/encyclopedia/graphics_file_format
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| | Introduction |
| | Dynamic range, however, is not only limited to file format, it is also dependent upon the output device (e.g. | | | dynamic range of an image is the ratio between the lightest and darkest portions of the image [6]. | | | Test Image 1: ‘nave.hdr’ When we converted the image from a high dynamic range hdr image to a low dynamic range jpg image without using a tone mapping operator, the low dynamic range LCD monitor could not render all of the pixels with any degree of visual fidelity (see Figure 1a). |
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http://www.cs.umd.edu/users/mount/Indep/Chihiro/paper-final.htm
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| | FTPOnline - Digital Design World 2004 - HDR Highs and Lows |
| | High dynamic range (HDR): True HDR image formats support up to 32 bits per channel, usually in "Float" format with an exponent. | | | Medium dynamic range (MDR): These images have between 8 and 16 bits of information per channel. | | | Medium dynamic range images can encode a far greater tonal range than we can produce on paper—up to 16 stops—but they still cannot encode the full tonal range of human vision. |
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http://www.fawcette.com/reports/ddwsf/2004/meyer/default_pf.asp
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| | Stitched HDRI |
| | This is a first attempt using fully automatic Gradient Domain High Dynamic Range Compression to compress the bightness range of the HDRI to the range of a computer monitor. | | | The scene you photograph to create your curve should have a high dynamic range of light, preferably the entire range of your camera, and the stops of your bracket should be taken in small increments. | | | Of course the number would change based on the dynamic range in any given scene but it would be a starting point for estimating the number and increments required. |
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http://www.gregdowning.com/HDRI/stitched
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| | Imaging On-Line Store |
| | The absence of a well-calibrated high dynamic range color image database of natural scenes is an impediment to developing such rendering algorithms for digital photography. | | | This suggests that future high dynamic range rendering algorithms need to account jointly for local color adaptation and local illumination level. | | | First, we discuss how the image dynamic range is affected by three main components in the imaging pipeline: the optics, the sensor and the color transformation. |
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http://www.imaging.org/store/epub.cfm?abstrid=8448
(268 words)
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| | The Future of Digital Imaging - High Dynamic Range Photography (HDR) |
| | There are a range of proprietary formats that offer medium or high dynamic range. | | | Newsflash: Adobe has announced Photoshop CS will support High Dynamic Range imaging in their next version, available in May 2005. | | | Of all imaging tasks, editing is the one that demands the highest dynamic range. |
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http://www.cybergrain.com/tech/hdr
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| | Seminari/Rendering High-Dynamic Range Images: Retinex Algorithms that Mimic Human Vision |
| | Rendering High-Dynamic Range Images: Retinex Algorithms that Mimic Human Vision | | | High-dynamic-range Retinex algorithms share a common mechanism with vision, namely they are based on spatial comparison of pixels in all regions of the captured image. | | | As shown by Ansel Adams, and Jones and Condit, outdoor scenes typically have dynamic ranges of 1000 to 1 in radiances. |
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http://www.dsi.unimi.it/seminario.php?z=0;id=275
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| | Recovering High Dynamic Range Radiance Maps from Photographs |
| | "High Dynamic Range Imaging" at the USC Institute for Creative Technologies are available here as | | | software package called mkhdr available for assembling high dynamic range radiance maps from series of photographs. | | | Neither computer screens nor paper can display nearly the dynamic range (ratio between dark and bright regions) as what is present in the real world, and as a result cameras are not designed to capture even close to such a range. |
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http://athens.ict.usc.edu/Research/HDR
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| | GameDev.net - High Dynamic Range Rendering |
| | High Dynamic Range is just a neat term for "storing color values much greater than the usual 0.0f to 1.0f used in graphics". | | | With the advent of powerful graphics hardware over the past few years, thanks to Moore's law of course, the process can now be implemented on graphics hardware in real-time. | | | What I will teach you is how to load a.hdr file and use it to texture a simple quad, which will then be rendered with "natural light". |
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http://www.gamedev.net/reference/articles/article2108.asp
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| | IVRG - Image and Visual Representation Group |
| | We show that our method efficiently renders high dynamic range images and we compare our results with the current state of the art. | | | We propose a new method to render high dynamic range images that models global and local adaptation of the human visual system. | | | Secondly, only the luminance channel is processed, which is defined by the first component of a principal component analysis. |
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http://ivrgwww.epfl.ch/index.php?name=Bio-inspired_Image_Enhancement
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| | HDR |
| | This high dynamic range information is combined and the tonal range is reduced using a means of tonal mapping. | | | Another use for HDR images is to actually capture the full dynamic range of a scene for scientific or industrial uses. | | | While 24-bit color is often sufficient for common computer graphics and print work this limited range of levels can lead to some problems with photography. |
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http://www.panoscan.com/HDR.html
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| | Programmable Imaging Using a Digital Micromirror Array |
| | Although the mirrors of this device can only be positioned in one of two states, we show that our system can be used to implement a wide variety of imaging functions, including, high dynamic range imaging, feature detection, and object recognition. | | | In this paper, we introduce the notion of a programmable imaging system. | | | We conclude with a discussion on how a micro-mirror array can be used to efficiently control field of view without the use of moving parts. |
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http://csdl2.computer.org/persagen/DLAbsToc.jsp?resourcePath=/dl/proceedings/&toc=comp/proceedings/cvpr/2004/2158/01/2158toc.xml&DOI=10.1109/CVPR.2004.193
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| | High Dynamic Range Imaging with SpheronVR and SpheroCam HDR |
| | High Dynamic Range imaging is, first of all, about not losing information when capturing an image: If an object in an image is a million times brighter than another object, then its pixel values should be a million times higher, and not just 255. | | | Today, most rendering software implements image-based lighting by using full spherical and High Dynamic Range images as lighting sources. | | | High Dyanmic Range imaging means measuring the real world luminosity as it is, without clipping of pixels or bleaching of regions within the image. |
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http://www.spheron.com/www.spheron.com-verio/products/SpheroCamHDR/spherocam_hdr.html
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| | WebHDR Home |
| | High dynamic range (HDR) images store the information in a format that has a range of many orders of magnitude. | | | Not only is computer display technology still very far from delivering images that have a luminous range even close to what the human eye can process. | | | Once adapted, the eye can cope with a luminance range of 1:1000, but for a part of the scene, this can be as high as 1:10000. |
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http://luminance.londonmet.ac.uk/webhdr/index.shtml
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