6,334 research outputs found
Digital Image Access & Retrieval
The 33th Annual Clinic on Library Applications of Data Processing, held at the University of Illinois at Urbana-Champaign in March of 1996, addressed the theme of "Digital Image Access & Retrieval." The papers from this conference cover a wide range of topics concerning digital imaging technology for visual resource collections. Papers covered three general areas: (1) systems, planning, and implementation; (2) automatic and semi-automatic indexing; and (3) preservation with the bulk of the conference focusing on indexing and retrieval.published or submitted for publicatio
A proposal for Video Signature Tool and Video Fingerprinting
In this document we present and evaluate a video signature system, proposed by Signals and Communications Laboratory – Department of Electronic for Automation, University of Brescia (Italy)
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Intelligent image cropping and scaling
This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University, 2011.Nowadays, there exist a huge number of end devices with different screen properties for
watching television content, which is either broadcasted or transmitted over the internet.
To allow best viewing conditions on each of these devices, different image formats have
to be provided by the broadcaster. Producing content for every single format is,
however, not applicable by the broadcaster as it is much too laborious and costly.
The most obvious solution for providing multiple image formats is to produce one high resolution format and prepare formats of lower resolution from this. One possibility to do this is to simply scale video images to the resolution of the target image format. Two significant drawbacks are the loss of image details through ownscaling and possibly unused image areas due to letter- or pillarboxes. A preferable solution is to find the contextual most important region in the high-resolution format at first and crop this area with an aspect ratio of the target image format afterwards. On the other hand, defining
the contextual most important region manually is very time consuming. Trying to apply that to live productions would be nearly impossible. Therefore, some approaches exist that automatically define cropping areas. To do so, they extract visual features, like moving reas in a video, and define regions of interest
(ROIs) based on those. ROIs are finally used to define an enclosing cropping area. The
extraction of features is done without any knowledge about the type of content. Hence,
these approaches are not able to distinguish between features that might be important in
a given context and those that are not.
The work presented within this thesis tackles the problem of extracting visual features based on prior knowledge about the content. Such knowledge is fed into the system in form of metadata that is available from TV production environments. Based on the
extracted features, ROIs are then defined and filtered dependent on the analysed
content. As proof-of-concept, this application finally adapts SDTV (Standard Definition Television) sports productions automatically to image formats with lower resolution through intelligent cropping and scaling. If no content information is available, the system can still be applied on any type of content through a default mode. The presented approach is based on the principle of a plug-in system. Each plug-in
represents a method for analysing video content information, either on a low level by
extracting image features or on a higher level by processing extracted ROIs. The
combination of plug-ins is determined by the incoming descriptive production metadata
and hence can be adapted to each type of sport individually. The application has been comprehensively evaluated by comparing the results of the system against alternative cropping methods. This evaluation utilised videos which were manually cropped by a professional video editor, statically cropped videos and simply scaled, non-cropped videos. In addition to and apart from purely subjective evaluations,
the gaze positions of subjects watching sports videos have been measured and compared
to the regions of interest positions extracted by the system
Nonrigid reconstruction of 3D breast surfaces with a low-cost RGBD camera for surgical planning and aesthetic evaluation
Accounting for 26% of all new cancer cases worldwide, breast cancer remains
the most common form of cancer in women. Although early breast cancer has a
favourable long-term prognosis, roughly a third of patients suffer from a
suboptimal aesthetic outcome despite breast conserving cancer treatment.
Clinical-quality 3D modelling of the breast surface therefore assumes an
increasingly important role in advancing treatment planning, prediction and
evaluation of breast cosmesis. Yet, existing 3D torso scanners are expensive
and either infrastructure-heavy or subject to motion artefacts. In this paper
we employ a single consumer-grade RGBD camera with an ICP-based registration
approach to jointly align all points from a sequence of depth images
non-rigidly. Subtle body deformation due to postural sway and respiration is
successfully mitigated leading to a higher geometric accuracy through
regularised locally affine transformations. We present results from 6 clinical
cases where our method compares well with the gold standard and outperforms a
previous approach. We show that our method produces better reconstructions
qualitatively by visual assessment and quantitatively by consistently obtaining
lower landmark error scores and yielding more accurate breast volume estimates
Towards Automatic Blotch Detection for Film Restoration by Comparison of Spatio-Temporal Neighbours
In this paper, a new method of blotch detection for digitised film sequences is proposed. Due to the aging of film stocks, their poor storage and/or repeated viewing, it is estimated that approximately 50% of all films produced prior to 1950 have either been destroyed or rendered unwatchable [1,2]. To prevent their complete destruction, original film reels must be scanned into digital format; however, any defects such as blotches will be retained. By combining a variation of a linear time, contour tracing technique with a simple temporal nearest neighbour algorithm, a preliminary detection system has been created. Using component labelling of dirt and sparkle the overall performance of the completed system, in terms of time and accuracy, will compare favourably to traditional motion compensated detection methods. This small study (based on 13 film sequences) represents a significant first step towards automatic blotch detection
Posicionamiento visual con resolución subpixel de objetos marcados que se desplazan en un plano: conceptos básicos y aplicaciones
Vision is a convenient tool for position measurements. In this paper, we present several applications in which a reference pattern can be defined on the target for a priori knowledge of image features and further optimization by software. Selecting pseudoperiodic patterns leads to high resolution in absolute phase measurements. This method is adapted to position encoding of live cell culture boxes. Our goal is to capture each biological image along with its absolute highly accurate position regarding the culture box itself. Thus, it becomes straightforward to find again an already observed region of interest when a culture box is brought back to the microscope stage from the cell incubator where it was temporarily placed for cell culture. In order to evaluate the performance of this method, we tested it during a wound healing assay of human liver tumor-derived cells. In this case, the procedure enabled more accurate measurements of the wound healing rate than the usual method. It was also applied to the characterization of the in-plane vibration amplitude from a tapered probe of a shear force microscope. The amplitude was interpolated by a quartz tuning fork with an attached pseudo-periodic pattern. Nanometer vibration amplitude resolution is achieved by processing the pattern images. Such pictures were recorded by using a common 20x magnification lens.La visión es una herramienta conveniente para mediciones de posición. En este artículo, presentamos aplicaciones en las que un patrón de referencia puede ser adherido al objeto de interés. Ésto permite tener un conocimiento a priori de las características de la imagen y así poder optimizar el software. Como patrón de referencia se usan patrones pseudo-periódicos, los cuales permiten una alta resolución en las mediciones de fase absoluta. El método es adaptado para codificar la posición de soportes de cultivos celulares, con el fin de documentar cada imagen biológica registrada con su posición absoluta. Por lo tanto, resulta sencillo encontrar de nuevo una región de interés, observada previamente, cuando una caja de cultivo es traída de nuevo al microscopio luego de estar en una incubadora. Para evaluar el método, éste se utilizó durante un ensayo de “cicatrización de herida” de un cultivo celular derivado de tumores hepáticos. En este caso, el método permite obtener mediciones más precisas de la tasa de “cicatrización”, comparado a los resultados obtenidos con el método usual. El método propuesto también se aplica a la caracterización de la amplitud de vibración en el plano de una sonda de un microscopio de fuerza atómica. La amplitud fue interpolada por medio de un diapasón de cuarzo al cual se la adhirió un patrón pseudo-periódico. A partir del procesamiento de las imágenes del patrón, se logra obtener resolución nanométrica en la medida de la amplitud de la vibración. Estas imágenes fueron obtenidas con un microscopio óptico con magnificación 20x
Posicionamiento visual con resolución subpixel de objetos marcados que se desplazan en un plano: conceptos básicos y aplicaciones
Vision is a convenient tool for position measurements. In this paper, we present several applications in which a reference pattern can be defined on the target for a priori knowledge of image features and further optimization by software. Selecting pseudoperiodic patterns leads to high resolution in absolute phase measurements. This method is adapted to position encoding of live cell culture boxes. Our goal is to capture each biological image along with its absolute highly accurate position regarding the culture box itself. Thus, it becomes straightforward to find again an already observed region of interest when a culture box is brought back to the microscope stage from the cell incubator where it was temporarily placed for cell culture. In order to evaluate the performance of this method, we tested it during a wound healing assay of human liver tumor-derived cells. In this case, the procedure enabled more accurate measurements of the wound healing rate than the usual method. It was also applied to the characterization of the in-plane vibration amplitude from a tapered probe of a shear force microscope. The amplitude was interpolated by a quartz tuning fork with an attached pseudo-periodic pattern. Nanometer vibration amplitude resolution is achieved by processing the pattern images. Such pictures were recorded by using a common 20x magnification lens.La visión es una herramienta conveniente para mediciones de posición. En este artículo, presentamos aplicaciones en las que un patrón de referencia puede ser adherido al objeto de interés. Ésto permite tener un conocimiento a priori de las características de la imagen y así poder optimizar el software. Como patrón de referencia se usan patrones pseudo-periódicos, los cuales permiten una alta resolución en las mediciones de fase absoluta. El método es adaptado para codificar la posición de soportes de cultivos celulares, con el fin de documentar cada imagen biológica registrada con su posición absoluta. Por lo tanto, resulta sencillo encontrar de nuevo una región de interés, observada previamente, cuando una caja de cultivo es traída de nuevo al microscopio luego de estar en una incubadora. Para evaluar el método, éste se utilizó durante un ensayo de “cicatrización de herida” de un cultivo celular derivado de tumores hepáticos. En este caso, el método permite obtener mediciones más precisas de la tasa de “cicatrización”, comparado a los resultados obtenidos con el método usual. El método propuesto también se aplica a la caracterización de la amplitud de vibración en el plano de una sonda de un microscopio de fuerza atómica. La amplitud fue interpolada por medio de un diapasón de cuarzo al cual se la adhirió un patrón pseudo-periódico. A partir del procesamiento de las imágenes del patrón, se logra obtener resolución nanométrica en la medida de la amplitud de la vibración. Estas imágenes fueron obtenidas con un microscopio óptico con magnificación 20x
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