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Representations automatically evoked by a depicted handTeskey, Morgan 02 September 2022 (has links)
A conflicted and contentious literature has emerged from the proposal that visuospatial information from static images can automatically trigger associated motor representations. Curiously, investigations into this visual-motor relationship have predominantly focused on images of manipulable objects, while relatively little work has made use of images of body parts- whose referents are represented directly in the motor system. Limited work has made use of hand images as task-irrelevant primes, in an effort to determine whether a hand image automatically evokes a motor representation of the viewer’s corresponding limb. The results of these studies have provided diverging evidence and have resulted in competing theoretical accounts. Here, I present results from a series of stimulus-response compatibility experiments that were designed to probe the nature of representations generated by static hand images, while also addressing potential methodological weaknesses of the previous works. The results show that both stimulus properties and task demands influence the way in which an image of a hand is coded. Notably, I provide clear evidence that motor representations can be evoked automatically by depictions of particular hand postures, but that these representations are not an automatic, ineluctable component of the general processing of any hand image. These results not only contribute to a more unified account of hand representations, but also have wider implications for our understanding of the conditions under which static displays can engage motor representations. / Graduate
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Visioning The Nation: Classical Images As Allegory During The French RevolutionReed, Kristopher Guy 01 January 2007 (has links)
In the latter half of the Eighteenth Century, France experienced a seismic shift in the nature of political culture. The king gave way to the nation at the center of political life as the location of sovereignty transferred to the people. While the French Revolution changed the structure of France's government, it also changed the allegorical representations of the nation. At the Revolution's onset, the monarchy embodied both the state and nation as equated ideas. During the Revolutionary Decade and through the reign of Napoleon different governments experienced the need to reorient these symbols away from the person of the king to the national community. Following the king's execution, the Committee government invented connections to the ancient past in order to build legitimacy for their rule in addition to extricating the monarchy's symbols from political life. During the rule of Napoleon, he used classical symbols to associate himself with Roman Emperors to embody the nation in his person. Through an examination of the different types of classical symbols that each government illustrates the different ways that attempted to symbolically document this important shift in the location of sovereignty away from the body of the king to the nation.
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The effects of imposed image movement on visual disappearances /Henderson, A. Steven January 1987 (has links)
No description available.
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Classification images for contrast discriminationMcIlhagga, William H. 03 March 2021 (has links)
Yes / Contrast discrimination measures the smallest difference in contrast (the threshold) needed to successfully tell two stimuli apart. The contrast discrimination threshold typically increases with contrast. However, for low spatial frequency gratings the contrast threshold first increases, but then starts to decrease at contrasts above about 50%. This behaviour was originally observed in contrast discrimination experiments using dark spots as stimuli, suggesting that the contrast discrimination threshold for low spatial frequency gratings may be dominated by responses to the dark parts of the sinusoid. This study measures classification images for contrast discrimination experiments using a 1 cycle per degree sinusoidal grating at contrasts of 0, 25%, 50% and 75%. The classification images obtained clearly show that observers emphasize the darker parts of the sinusoidal grating (i.e. the troughs), and this emphasis increases with contrast. At 75% contrast, observers almost completely ignored the bright parts (peaks) of the sinusoid, and for some observers the emphasis on the troughs is already evident at contrasts as low as 25%. Analysis using a Hammerstein model suggests that the bias towards the dark parts of the stimulus is due to an early nonlinearity, perhaps similar to that proposed by Whittle.
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Automated system design for the efficient processing of solar satellite images. Developing novel techniques and software platform for the robust feature detection and the creation of 3D anaglyphs and super-resolution images for solar satellite images.Zraqou, Jamal Sami January 2011 (has links)
The Sun is of fundamental importance to life on earth and is studied by scientists from many disciplines. It exhibits phenomena on a wide range of observable scales, timescales and wavelengths and due to technological developments there is a continuing increase in the rate at which solar data is becoming available for study which presents both opportunities and challenges. Two satellites recently launched to observe the sun are STEREO (Solar TErrestrial RElations Observatory), providing simultaneous views of the SUN from two different viewpoints and SDO (Solar Dynamics Observatory) which aims to study the solar atmosphere on small scales and times and in many wavelengths. The STEREO and SDO missions are providing huge volumes of data at rates of about 15 GB per day (initially it was 30 GB per day) and 1.5 terabytes per day respectively. Accessing these huge data volumes efficiently at both high spatial and high time resolutions is important to support scientific discovery but requires increasingly efficient tools to browse, locate and process specific data sets.
This thesis investigates the development of new technologies for processing information contained in multiple and overlapping images of the same scene to produce images of improved quality. This area in general is titled Super Resolution (SR), and offers a technique for reducing artefacts and increasing the spatial resolution. Another challenge is to generate 3D images such as Anaglyphs from uncalibrated pairs of SR images. An automated method to generate SR images is presented here. The SR technique consists of three stages: image registration, interpolation and filtration. Then a method to produce enhanced, near real-time, 3D solar images from uncalibrated pairs of images is introduced.
Image registration is an essential enabling step in SR and Anaglyph processing. An accurate point-to-point mapping between views is estimated, with multiple images registered using only information contained within the images themselves. The performances of the proposed methods are evaluated using benchmark evaluation techniques. A software application called the SOLARSTUDIO has been developed to integrate and run all the methods introduced in this thesis. SOLARSTUDIO offers a number of useful image processing tools associated with activities highly focused on solar images including: Active Region (AR) segmentation, anaglyph creation, solar limb extraction, solar events tracking and video creation.
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L’effervescence des images : les archives de la Planète d’Albert Kahn (1908-2018) / The Effervescence of Images : the Archives of the Planet by Albert Kahn (1908-2018)Genoudet, Adrien 06 December 2018 (has links)
L’axe principal de ce travail de thèse est de s’intéresser à ce projet visuel dans l’œuvre d’Albert Kahn et d’ouvrir le champ en s’intéressant aux devenirs des films des Archives de la Planète. Pour cela, la thèse s’appuie sur la totalité des archives administratives du Musée Albert Kahn, sur les archives d’Albert Kahn et sur ses nombreux proches, sur les archives départementales et nationales ou encore à travers des enquêtes menés dans les archives de l’INA, des centres d’art et les archives du film. En s’intéressant, dans un premier temps, à la figure kahnienne à travers la construction des discours contemporains ou posthumes de Kahn, la thèse s’oriente dans un deuxième temps vers une analyse du projet visuel kahnien. En s’appuyant sur des penseurs contemporains de Kahn et sur certains de ses écrits, ce deuxième temps tente de comprendre comment les Archives de la Planète sont rendues possibles et en quoi elles s’inscrivent dans une pensée de l’image à la fois globale et spécifique. Enfin, la troisième partie de ce travail explore, premièrement, la « mise en disponibilités » des films des Archives de la Planète en partant de la mort d’Albert Kahn jusqu’au début des années 2000 en s’appuyant sur l’histoire de l’institution muséale et sur ses satellites – comme la « Cinémathèque de Boulogne ». Le deuxième temps de la troisième partie ouvre la réflexion en se concentrant sur les devenirs des Archives de la Planète à travers des études de cas d’appropriations des films kahniens dans des productions extérieures (Chris Marker, Abel Gance, Nicole Vedrès, Frédéric Rossif etc.) et à la télévision. / The main approach of this PhD is to focus on the visual project within Albert Kahn’s work and to broaden the scope by studying what will become of the films from the Archives of the Planet. To achieve this goal, the thesis draws on the whole administrative archives of the Albert Kahn Museum, on the archives of Albert Kahn and his numerous relatives, on the departmental and national archives and through investigations conducted in the archives of the INA (the National Institute for Audio-visual Media), art centres and the film’s archives. By first looking at the kahnian figure through the construction of Kahn’s contemporary and posthumous speeches, the thesis then takes a turn towards an analysis of the kahnian visual project. As it draws on thinkers contemporary to Kahn and on some of his writings, this second part attempts to grasp how the Archives of the Planet have been made possible and how they are embedded in a thinking, both global and specific, on images. Finally, the third part of this work first delves into the period when the films of the Archives of the Planet were “made available” from Albert Kahn’s death to the early 2000s, by drawing on the history of the museal institution and its satellites – such as the “Cinémathèque de Boulogne.” The third part then opens up the reflection by focusing on the futures of the Archives of the Planet and, by studying cases of appropriation of the kahnian films in external productions (Chris Marker, Abel Gance, Nicole Vedrès, Frédéric Rossif etc.) and on television.
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Reconstruction of 3D scenes from pairs of uncalibrated images : creation of an interactive system for extracting 3D data points and investigation of automatic techniques for generating dense 3D data maps from pairs of uncalibrated images for remote sensing applicationsAlkhadour, Wissam Mohamad January 2010 (has links)
Much research effort has been devoted to producing algorithms that contribute directly or indirectly to the extraction of 3D information from a wide variety of types of scenes and conditions of image capture. The research work presented in this thesis is aimed at three distinct applications in this area: interactively extracting 3D points from a pair of uncalibrated images in a flexible way; finding corresponding points automatically in high resolution images, particularly those of archaeological scenes captured from a freely moving light aircraft; and improving a correlation approach to dense disparity mapping leading to 3D surface reconstructions. The fundamental concepts required to describe the principles of stereo vision, the camera models, and the epipolar geometry described by the fundamental matrix are introduced, followed by a detailed literature review of existing methods. An interactive system for viewing a scene via a monochrome or colour anaglyph is presented which allows the user to choose the level of compromise between amount of colour and ghosting perceived by controlling colour saturation, and to choose the depth plane of interest. An improved method of extracting 3D coordinates from disparity values when there is significant error is presented. Interactive methods, while very flexible, require significant effort from the user finding and fusing corresponding points and the thesis continues by presenting several variants of existing scale invariant feature transform methods to automatically find correspondences in uncalibrated high resolution aerial images with improved speed and memory requirements. In addition, a contribution to estimating lens distortion correction by a Levenberg Marquard based method is presented; generating data strings for straight lines which are essential input for estimating lens distortion correction. The remainder of the thesis presents correlation based methods for generating dense disparity maps based on single and multiple image rectifications using sets of automatically found correspondences and demonstrates improvements obtained using the latter method. Some example views of point clouds for 3D surfaces produced from pairs of uncalibrated images using the methods presented in the thesis are included.
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Design and analysis of discrete cosine transform-based watermarking algorithms for digital images : development and evaluation of blind discrete cosine transform-based watermarking algorithms for copyright protection of digital images using handwritten signatures and mobile phone numbersAl-Gindy, Ahmed M. N. January 2011 (has links)
This thesis deals with the development and evaluation of blind discrete cosine transform-based watermarking algorithms for copyright protection of digital still images using handwritten signatures and mobile phone numbers. The new algorithms take into account the perceptual capacity of each low frequency coefficients inside the Discrete Cosine Transform (DCT) blocks before embedding the watermark information. They are suitable for grey-scale and colour images. Handwritten signatures are used instead of pseudo random numbers. The watermark is inserted in the green channel of the RGB colour images and the luminance channel of the YCrCb images. Mobile phone numbers are used as watermarks for images captured by mobile phone cameras. The information is embedded multiple-times and a shuffling scheme is applied to ensure that no spatial correlation exists between the original host image and the multiple watermark copies. Multiple embedding will increase the robustness of the watermark against attacks since each watermark will be individually reconstructed and verified before applying an averaging process. The averaging process has managed to reduce the amount of errors of the extracted information. The developed watermarking methods are shown to be robust against JPEG compression, removal attack, additive noise, cropping, scaling, small degrees of rotation, affine, contrast enhancements, low-pass, median filtering and Stirmark attacks. The algorithms have been examined using a library of approximately 40 colour images of size 512 512 with 24 bits per pixel and their grey-scale versions. Several evaluation techniques were used in the experiment with different watermarking strengths and different signature sizes. These include the peak signal to noise ratio, normalized correlation and structural similarity index measurements. The performance of the proposed algorithms has been compared to other algorithms and better invisibility qualities with stronger robustness have been achieved.
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Automated system design for the efficient processing of solar satellite images : developing novel techniques and software platform for the robust feature detection and the creation of 3D anaglyphs and super-resolution images for solar satellite imagesZraqou, Jamal Sami January 2011 (has links)
The Sun is of fundamental importance to life on earth and is studied by scientists from many disciplines. It exhibits phenomena on a wide range of observable scales, timescales and wavelengths and due to technological developments there is a continuing increase in the rate at which solar data is becoming available for study which presents both opportunities and challenges. Two satellites recently launched to observe the sun are STEREO (Solar TErrestrial RElations Observatory), providing simultaneous views of the SUN from two different viewpoints and SDO (Solar Dynamics Observatory) which aims to study the solar atmosphere on small scales and times and in many wavelengths. The STEREO and SDO missions are providing huge volumes of data at rates of about 15 GB per day (initially it was 30 GB per day) and 1.5 terabytes per day respectively. Accessing these huge data volumes efficiently at both high spatial and high time resolutions is important to support scientific discovery but requires increasingly efficient tools to browse, locate and process specific data sets. This thesis investigates the development of new technologies for processing information contained in multiple and overlapping images of the same scene to produce images of improved quality. This area in general is titled Super Resolution (SR), and offers a technique for reducing artefacts and increasing the spatial resolution. Another challenge is to generate 3D images such as Anaglyphs from uncalibrated pairs of SR images. An automated method to generate SR images is presented here. The SR technique consists of three stages: image registration, interpolation and filtration. Then a method to produce enhanced, near real-time, 3D solar images from uncalibrated pairs of images is introduced. Image registration is an essential enabling step in SR and Anaglyph processing. An accurate point-to-point mapping between views is estimated, with multiple images registered using only information contained within the images themselves. The performances of the proposed methods are evaluated using benchmark evaluation techniques. A software application called the SOLARSTUDIO has been developed to integrate and run all the methods introduced in this thesis. SOLARSTUDIO offers a number of useful image processing tools associated with activities highly focused on solar images including: Active Region (AR) segmentation, anaglyph creation, solar limb extraction, solar events tracking and video creation.
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Reconstruction of 3D scenes from pairs of uncalibrated images. Creation of an interactive system for extracting 3D data points and investigation of automatic techniques for generating dense 3D data maps from pairs of uncalibrated images for remote sensing applications.Alkhadour, Wissam M. January 2010 (has links)
Much research effort has been devoted to producing algorithms that contribute directly or indirectly to the extraction of 3D information from a wide variety of types of scenes and conditions of image capture. The research work presented in this thesis is aimed at three distinct applications in this area: interactively extracting 3D points from a pair of uncalibrated images in a flexible way; finding corresponding points automatically in high resolution images, particularly those of archaeological scenes captured from a freely moving light aircraft; and improving a correlation approach to dense disparity mapping leading to 3D surface reconstructions.
The fundamental concepts required to describe the principles of stereo vision, the camera models, and the epipolar geometry described by the fundamental matrix are introduced, followed by a detailed literature review of existing methods.
An interactive system for viewing a scene via a monochrome or colour anaglyph is presented which allows the user to choose the level of compromise between amount of colour and ghosting perceived by controlling colour saturation, and to choose the depth plane of interest. An improved method of extracting 3D coordinates from disparity values when there is significant error is presented.
Interactive methods, while very flexible, require significant effort from the user finding and fusing corresponding points and the thesis continues by presenting several variants of existing scale invariant feature transform methods to automatically find correspondences in uncalibrated high resolution aerial images with improved speed and memory requirements. In addition, a contribution to estimating lens distortion correction by a Levenberg Marquard based method is presented; generating data strings for straight lines which are essential input for estimating lens distortion correction.
The remainder of the thesis presents correlation based methods for generating dense disparity maps based on single and multiple image rectifications using sets of automatically found correspondences and demonstrates improvements obtained using the latter method. Some example views of point clouds for 3D surfaces produced from pairs of uncalibrated images using the methods presented in the thesis are included. / Al-Baath University / The appendices files and images are not available online.
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