Subjective assessment of super multiview video with coding artifacts

The subjective assessment of super multiview (SMV) video considers two main perceptual factors: image quality and visual comfort at the viewpoint transition. While previous works only covered raw content with high levels of visual comfort, this work supersedes them by targeting the subjective assessment of SMV content with coding artifacts. The outcome of this analysis yields important conclusions regarding the relationship between these two factors, indicating that 1) the perceived image quality is independent from the view point change speed, and 2) the perceived visual comfort at the view point transition is independent from the image quality. These conclusions facilitate the extension of the scope of existing subjective perception models, designed for raw SMV content, to coded content

Exploracion de los Mercados de Boston y Washington D.C. para flores de corte, Clavales y Liliums

96 p.Esta investigación tiene como finalidad generar información valiosa acerca de los mercados de Boston y Washington D.C. para flores de corte producidas en Chile, específicamente Claveles y Liliums, de modo, que sea aprovechado por la Agricultura Familiar Campesina en su programa de iniciación exportadora, la cual es una institución apoyada por algunos organismos de gobierno como el Ministerio de Agricultura, INDAP y ProChile, a través de su programa Interpac 2004. Dichos mercados se analizaron mediante cinco objetivos específicos, que dicen relación con: caracterizar los mercados de Boston y Washington D.C. en término de las variables macroeconómicas, describir estándares de calidad básicos y normas fitosanitarias de las flores de corte, analizar la logística de exportación óptima para la inserción del producto, proponer una estrategia de mix comercial para los mercados seleccionados y realizar un análisis de precios, de modo de determinar la conveniencia de exportación. Metodológicamente, este estudio se formuló con una investigación exploratoria, en una primera instancia, debido a la escasa información de los nichos de mercado seleccionados; sin embargo, en una segunda instancia se tornó descriptiva de modo de otorgar la información requerida por dicho estudio. A su vez, se cuenta con información primaria que se sustenta principalmente en entrevistas y contactos vía e-mail con la Dirección de Promoción de Exportaciones (ProChile) y con el tutor del Proyecto Flores para la Agricultura Familiar Campesina; también se presenta información secundaria principalmente obtenida desde Internet. Al finalizar este estudio, se concluye que la vía de ingreso más apropiada para las flores que llegan a los mercados seleccionados es el Aeropuerto John F. Kennedy, ubicado en la ciudad de Nueva York, por su cercanía a estos mercados. Por otro lado, a raíz del marketing mix realizado se obtiene que los Claveles tienen poca oportunidad para competir con Colombia, principal exportador de esta flor a Estados Unidos, debido a su alta calidad y experiencia en estos mercados, lo que hace que tengan un margen de ganancia bastante pequeño en comparación con los Liliums, el cual corresponde a US $0,13 para el mercado de Boston y de US$0,03 para el mercado de Washington D.C.. En cuanto al Lilium se visualizan condiciones favorables par

Validation of a novel approach to subjective quality evaluation of conventional and 3D broadcasted video services

Transmission errors are the main cause of degradation of the quality of real broadcasted video services. Therefore, knowing their impact on the quality of experience of the end users is a crucial issue. For instance, it would help to improve the performance of the distribution systems, and to develop monitoring tools to automatically estimate the quality perceived by the end users. In this paper we validate a subjective evaluation approach specifically designed to obtain meaningful results of the effects of degradations caused by transmission errors. This methodology has been already used in our previous works with monoscopic and stereoscopic videos. The validation is done by comparing the subjective ratings obtained for typical transmission errors with the proposed methodology and with the standard method Absolute Category Rating. The results show that the proposed approach could provide more representative evaluations of the quality of experience perceived by end users of conventional and 3D broadcasted video services

Perceptual distortion modeling for side-by-side 3D video delivery

A frame-level distortion model based on perceptual features of the human visual system is proposed to improve the performance of unequal error protection strategies and provide better quality of experience to users in Side-by-Side 3D video delivery systems

Subjective study of adaptive streaming strategies for 3DTV

Although the delivery of 3D video services to households is nowadays a reality thanks to frame-compatible formats, many efforts are being made to obtain efficient methods to transmit 3D content offering a high quality of experience to the end users. In this paper, a stereoscopic video streaming scenario is considered and the perceptual impact of various strategies applicable to adaptive streaming situations are compared. Specifically, the mechanisms are based on switching between copies of the content with different coding qualities, on discarding frames of the sequence, on switching from 3D to 2D and on using asymmetric coding of the stereo views. In addition, when video freezes happen, the possibility of keeping the end-to-end latency or maintaining the continuity of the video are considered. These aspects were evaluated carrying out a subjective assessment test considering also visual discomfort issues using a methodology designed to keep as far as possible domestic viewing conditions

Monitoring packet loss impact in IPTV and 3DTV receivers

Considering a scalable video quality monitoring architecture to detect transmission errors at households, we propose a technique to detect packet losses in IPTV and Side-by-Side 3DTV and evaluate their impact on the perceived quality

ViCoCoS-3D: Videoconferencing common scenes

This paper presents a 3D video dataset containing sequences with typical content from videoconferencing scenarios. The objective of this dataset is to provide freely-available sequences for the research community to support the develop-ment and evaluation of processing techniques applicable to 3D videoconferencing systems. Therefore, a detailed description of the generation process and the content characteristics is provided, together with insights of possible applications of the datase

Assessing Creativity In Engineering Students: A Comparative Between Degrees and Sudents In First And Last Year

An online open access test (CREAX self-assessment) has been used in this work so that students from degrees in engineering in the Universidad Polite¿cnica of Madrid (UPM) could self-assess their creative competence after several classroom activities. Different groups from the first year course have been statistically compared using data from their assessment. These first year students had different professors in the subject ?Technical Drawing? and belonged to several degrees in the UPM. They were as well compared regarding sex and a group of first year students was also compared to another last year group of the degree so as to observe possible differences in the achievement of this competence. Only one difference was detected concerning sex in one of the degrees. Among degrees, the higher marks obtained by students who had done specific exercises for the development of creativity in class is highlighted. Finally, a significantly high mark was observed in students during their last year of degree with respect to first year students. The tool CREAX has become very useful in the assessment of this competence in the UPM degrees in which it has been implemented

Subjective Evaluation of Transmission Errors in IPTV and 3DTV

The increase of multimedia services delivered over packet-based networks has entailed greater quality expectations of the end-users. This has led to an intensive research on techniques for evaluating the quality of experience perceived by the viewers of audiovisual content, considering the different degradations that it could suffer along the broadcasting system. In this paper, a comprehensive study of the impact of transmission errors affecting video and audio in IPTV is presented. With this aim, subjective assessment tests were carried out proposing a novel methodology trying to keep as close as possible home environment viewing conditions. Also 3DTV content in side-by-side format has been used in the experiments to compare the impact of the degradations. The results provide a better understanding of the effects of transmission errors, and show that the QoE related to the first approach of 3DTV is acceptable, but the visual discomfort that it causes should be reduced

Work on PETS Developed at CIEMAT

CIEMAT has been working on the RF power extractor so-called PETS (Power Extraction and Transfer Structure) for the CLIC Test Facility 3 (CTF3) since 2007. The first contribution has been installed at the Test Beam Line (TBL). Additionally, a new PETS configuration is presently under fabrication at CIEMAT and will be installed in the Test Module at CTF3. This paper describes the PETS prototypes design, fabrication and assembly techniques. The characterization of the devices with low RF power is also described.Comment: 9 pages, 9 figures, 3 tables, 10 references. Work presented in the LCWS1