Spelling suggestions: "subject:"digital cameras"" "subject:"digital kameras""
31 |
CMOS Active Pixel Sensors for Digital Cameras: Current State-of-the-ArtPalakodety, Atmaram 05 1900 (has links)
Image sensors play a vital role in many image sensing and capture applications. Among the various types of image sensors, complementary metal oxide semiconductor (CMOS) based active pixel sensors (APS), which are characterized by reduced pixel size, give fast readouts and reduced noise. APS are used in many applications such as mobile cameras, digital cameras, Webcams, and many consumer, commercial and scientific applications. With these developments and applications, CMOS APS designs are challenging the old and mature technology of charged couple device (CCD) sensors. With the continuous improvements of APS architecture, pixel designs, along with the development of nanometer CMOS fabrications technologies, APS are optimized for optical sensing. In addition, APS offers very low-power and low-voltage operations and is suitable for monolithic integration, thus allowing manufacturers to integrate more functionality on the array and building low-cost camera-on-a-chip. In this thesis, I explore the current state-of-the-art of CMOS APS by examining various types of APS. I show design and simulation results of one of the most commonly used APS in consumer applications, i.e. photodiode based APS. We also present an approach for technology scaling of the devices in photodiode APS to present CMOS technologies. Finally, I present the most modern CMOS APS technologies by reviewing different design models. The design of the photodiode APS is implemented using commercial CAD tools.
|
32 |
A color filter array interpolation method for digital cameras using alias cancellationAppia, Vikram V. 31 March 2008 (has links)
To reduce cost, many digital cameras use a single sensor array instead of using
three arrays for the red, green and blue. Thus at each pixel location only the red,
green or blue intensity value is available. And to generate a complete color image,
the camera must estimate the missing two values at each pixel location .Color filter
arrays are used to capture only one portion of the spectrum (Red, Green or Blue) at
each location. Various arrangements of the Color Filter Array (CFA) are possible, but
the Bayer array is the most commonly used arrangement and we will deal exclusively
with the Bayer array in this thesis.
Since each of the three colors channels are effectively downsampled, it leads to
aliasing artifacts. This thesis will analyze the effects of aliasing in the frequency-
domain and present a method to reduce the deterioration in image quality due to
aliasing artifacts.
Two reference algorithms, AH-POCS (Adams and Hamilton - Projection Onto
Convex Sets) and Adaptive Homogeneity-Directed interpolation, are discussed in de-
tail. Both algorithms use the assumption that there is high correlation in the high-
frequency regions to reduce aliasing. AH-POCS uses alias cancellation technique to
reduce aliasing in the red and blue images, while the Adaptive Homogeneity-Directed
interpolation algorithm is an edge-directed algorithm. We present here an algorithm
that combines these two techniques and provides a better result on average when
compared to the reference algorithms.
|
33 |
Digital high school photography curriculumWolin, Martin Michael 01 January 2003 (has links)
The purpose of this thesis is to create a high school digital photography curriculum that is relevant to real world application and would enable high school students to enter the work force with marketable skills or go on to post secondary education with advanced knowledge in the field of digital imaging.
|
34 |
Detecting near-UV and near-IR wavelengths with the FOVEON image sensorCheak, Seck Fai 12 1900 (has links)
Approved for public release; distribution in unlimited. / Traditionally, digital imaging systems rely on the use of dedicated photodetectors to capture specific wavelengths in the visible spectrum. These photodetectors, which are commonly made of silicon, are arranged as arrays to capture the red, green and blue wavelengths. The signal captured by the individual photodetectors must then be interpolated and integrated to obtain the closest color match and the finest possible resolution with reference to the actual object. The use of spatially separated detectors to sense primary colors reduces the resolution by a factor of three compared to black and white imaging. The FOVEON detector technology greatly improves the color and resolution of the image through its vertically arranged, triple well photodetector. This is achieved by exploiting the variation of absorption coefficient of silicon with wavelength in the visible spectrum. Hence, in a silicon detector, the shorter wavelength (e.g. blue) would be mainly absorbed at a shallow depth. A longer wavelength (e.g. red) would penetrate the material deeper than the shorter wavelengths and be primarily absorbed at a greater depth. By producing a layered silicon detector, all three primary colour wavelengths of red, green and blue can be captured simultaneously. This thesis aims to study the FOVEON camera's ability to image light from the near Infrared (NIR) to the Ultra-Violet (UV) range of the electromagnetic spectrum. The imaged obtained using a set of bandpass filters show that the camera has response both in the UV as well as NIR regions. / Major, Singapore Armed Forces
|
35 |
Dokumentace historických artefaktů s využitím blízké fotogrammetrie / Use of Close Range Photogrammetry for Documentation of Historical Artefacts.Naništa, Jiří January 2013 (has links)
This diploma thesis deals with the design and implementation of appropriate procedure photogrammetry processing of technical documentation of selected historical artifacts gauges. During processing was calibrated camera, historical gauges were photographed and metrological documented and model viualization was created.
|
36 |
La nueva corriente cinematográfica que propone Emmanuel Lubezki en sus películas de la última década / The new cinematographic current that Emmanuel Lubezki proposes in his filmsSosa Suarez, Ruben Enrique 04 May 2020 (has links)
En este estudio se examinan los recursos de la cinematografía de Emmanuel Lubezki en relación a las nuevas corrientes que se han generado debido al tratamiento que este le ha dado a sus películas de la última década, por medio de la investigación de papers anteriores que tratan el tema del cine de Lubezki y porque lo hace reconocido y único en su estilo, también, la visualización de variedad de entrevistas en las que Lubezki explica el sentido que el toma y lo que aprendió durante su crecimiento como cineasta en el cine de actual. La información recogida nos muestra los aspectos básicos en los que se fija un cinematógrafo, como la iluminación, la composición, las cámaras, objetivos, etc. Se realiza un estudio de todos estos elementos basados en el respectivo uso que hacia Lubezki de estos como estrategia para reconocer el estilo del cineasta. / This study examines the resources of Emmanuel Lubezki's cinematography in relation to the new currents that have been generated due to the treatment that he has given to his films of the last decade, through the investigation of previous papers that deal with the Lubezki's film theme and because it makes him recognized and unique in his style, also, the visualization of a variety of interviews in which Lubezki explains the meaning he takes and what he learned during his growth as a filmmaker in current cinema. The information collected shows us the basic aspects in which a cinematograph is fixed, such as lighting, composition, cameras, lenses, etc. A study is made of all these elements based on Lubezki's respective use of these as a strategy to recognize the filmmaker's style. / Trabajo de investigación
|
37 |
Video anatomy : spatial-temporal video profileCai, Hongyuan 31 July 2014 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / A massive amount of videos are uploaded on video websites, smooth video browsing, editing, retrieval, and summarization are demanded. Most of the videos employ several types of camera operations for expanding field of view, emphasizing events, and expressing cinematic effect. To digest heterogeneous videos in video websites and databases, video clips are profiled to 2D image scroll containing both spatial and temporal information for video preview. The video profile is visually continuous, compact, scalable, and indexing to each frame. This work analyzes the camera kinematics including zoom, translation, and rotation, and categorize camera actions as their combinations. An automatic video summarization framework is proposed and developed. After conventional video clip segmentation and video segmentation for smooth camera operations, the global flow field under all camera actions has been investigated for profiling various types of video. A new algorithm has been designed to extract the major flow direction and convergence factor using condensed images. Then this work proposes a uniform scheme to segment video clips and sections, sample video volume across the major flow, compute flow convergence factor, in order to obtain an intrinsic scene space less influenced by the camera ego-motion. The motion blur technique has also been used to render dynamic targets in the profile. The resulting profile of video can be displayed in a video track to guide the access to video frames, help video editing, and facilitate the applications such as surveillance, visual archiving of environment, video retrieval, and online video preview.
|
Page generated in 0.0583 seconds