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ICT Project 3D VIVANT– Deliverable 2.3 Contract no.: 248420 User Acceptance Validation Plan 4 END-USER ACCEPTANCE The aim of the user validation with end-users is to determine if they can use and enjoy the 3D holoscopic service scenarios envisaged in the project. These service scenarios, as described in the Use Cases Document (see Deliverable D2.1), have two main components for the end-user: 1) Broadcast TV, and 2) Online Hyperlinking. The validation of the Broadcast TV component will concentrate on the audiovisual aspects, while the validation of the Online Hyperlinking component will additionally address the interaction and scalability aspects of the service scenarios. The validation will address the general acceptability and perception of the service scenarios developed and also covers specific issues derived from the end-user requirements in Deliverable D2.1 The focus of the tests is not to validate 3D Television (TV) per se, but to concentrate on the benefits and characteristics of 3D holoscopic TV and object-based hyperlinked videos. 4.1 BROADCAST EXPERIENCE 4.1.1 Viewing Specific test criteria for validation by the end-user are based primarily on the end-user requirements. This will involve real 3D holoscopic images captured with the holoscopic camera and computer generated 3D holoscopic content, or a combination of both. To gain a broad user acceptance some basic requirements concerning the picture quality can be defined as follows: • Spatial resolution – As broadcasters tend to distribute their programmes in HDTV format and 2D, and first stereoscopic 3D movies are available on blu-ray discs that use full HD resolution (1920×1080 pixels), the users would expect the holoscopic image to deliver similar resolutions. It has to be investigated if the new viewing experience of the holoscopic image can legitimate resolutions lower than HD (at least 1280×720). • Colour – Certainly, colour is a very important parameter to reproduce a realistic image of the world and users will expect pictures which show colours in a most natural way. In order to investigate to what extent colour representation is a camera or a display issue, computer generated content could be used for comparison. To gain a better 3D viewing experience than with existing 3D technologies, the user would expect the shortcomings of stereoscopic and auto-stereoscopic technologies to be solved. Basic acceptance factors will be: • Free viewing – Like on 2D displays it should be possible for multiple persons to view the 3D holoscopic content without the need to wear special glasses and independent of the individual position in front of the screen. • Continuous parallax without distortions – Since current 3D technologies can only provide horizontal parallax, 3D VIVANT’s holoscopic 3D should deliver full horizontal and vertical parallax throughout the viewing zone without flipping or shear distortion. • Distinguish between 2D and 3D content – Because for some use cases a combination of 2D and 3D holoscopic content is needed, users should be able to distinguish between 2D and 3D content without optical or mental irritations and be able to watch 2D content on a holoscopic 3D display without distortion. During the user perception testing of the Broadcast TV viewing part, users will be asked to view the same computer generated 3D holoscopic content that is displayed on different display mediums. The 01.09.11 18
ICT Project 3D VIVANT– Deliverable 2.3 Contract no.: 248420 User Acceptance Validation Plan first one will be stereoscopic content generated from the 3D holoscopic content (through the 3D holoscopic software plug-in tool that will be developed in M18 under the scope of Deliverable D3.9) that will be displayed on a commercial 2D monitor with users wearing special 3D glasses. The second one will be 3D holoscopic content that is displayed on three different types of displays. User acceptance tests will largely depend on the viewing conditions during the test. ITU-R Recommendation BT.500, clause 2.1.2, viewing conditions are considered “slightly more critical than the optimal home viewing conditions” and optimal conditions are described. This lighting environment is suggested for evaluating the “quality at the consumer side of the TV chain” and could be adopted as a basis for the tests envisaged in the project just like the Preferred Viewing Distance (PVD) recommended in ITU-R BT.500. It should be taken into account that the main purpose of the ITU-R BT.500 is to define a standard viewing environment in order to obtain comparable results with different assessment sessions. However, the definition of optimal, or preferred, viewing conditions for a 3D display is still an open issue. Consequently, for the tests to be carried out in the frame of the project, the viewing environment suggested in ITU-R BT.500 will be implemented, whereas the parameters related to the display will be chosen so that the resulting viewing conditions will be felt optimal by the viewers. 4.1.2 Hearing Spatial audio generation and playback will also be an integral part of the 3D VIVANT system. The main goal is to provide a consistent spatial audio experience accompanying the holoscopic video content. Thus, at least the same degrees of freedom as possible with the holoscopic display and content should be provided to one or more end-users. The key objectives are to allow plausible localisation of objects in respect to the visual experience, perception of spatiality and depth, and an overall coherent immersive listening experience. For audio generation a new spherical surface microphone has been designed. Accordingly an interpolation algorithm has been developed, to simulate microphone positions on the spherical surface between the six existing microphones. This algorithm (and the spherical surface microphone itself) have to be assessed through listening tests to find out the quality level of sound with following criteria: • Sound colouration – A correct interpolation of microphone positions with as less as possible sound colouration in comparison to a real microphone at this position is very significant. This criterion will be tested with the MUSHRA (#2.4.1) method (without low anchor). Three variations of the developed algorithm and two known will be compared. • Quality of localisation – The spherical surface microphone can also be used for binaural hearing. Therefore the perceived localisation of a sound source has to match the real position as well as possible. To test the quality of localisation with the spherical surface microphone a listening test with pointing (#2.4.2) on a scale to indicate the perceived sound sources will be conducted. This test will also evaluate the quality of localisation using interpolated microphones with different algorithms. A dummy head Neumann KU-100 will also to be rated for comparing with the spherical surface microphone and the interpolation algorithms. Both tests will be conducted with headphone listening and a head-tracker for dynamic tracking of the (binaural) signal. The reference is an artificially created (computer simulated) spherical surface microphone with 360 microphones on the equatorial plane. Only expert listener will be consulted in case of the small differences between the stimuli. A training session preceding the listening test will familiarize the test persons with the rating procedure (especially for the pointing method) and the possible artefacts or differences. The spatial audio playback system will also be tested using the following criteria: 01.09.11 19
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