Fleming Lampi

An automatic cameraman in a lecture recording system

We describe the design and implementation of an automatic cameraman for lecture recording. A major problem with traditional lecture recordings is that they tend to be boring for the students, especially if only the slides and the audio of the lecturer are pre-sented. In a first step, we determine the tasks a real cameraman would have, in particular with respect to liveliness of the video. We then adapt these tasks to a computer system and show in detail how they can be implemented. In a second step, we describe how our algorithms support the virtual director system into which the automatic cameraman is integrated. We conclude that lecture re-cordings can be much more lively and interesting using our approach.

A Virtual Camera Team for Lecture Recording

We present the design and implementation of a virtual camera team for recording classroom lectures. Our approach to lecture recording, with well-defined tasks for each module, has two significant advantages. First, the workload is distributed; for example, the camera-operator modules and not the director module produce the images. Second, its easier to implement complex cinematographic rules using the well-defined roles of the virtual team members and the communication between them. In this way, the virtual camera teams behavior mimics the behavior of a human camera team and thus leads to more lively recordings than earlier approaches.

Automatic scaling and cropping of videos for devices with limited screen resolution

A large number of previously recorded videos cannot be directly visualized on mobile devices like PDAs or mobile phones due to an inappropriate screen resolution of their displays. Transcoding can be used to change the resolution, however, the usual transcoding algorithms have problems preserving the semantic content. For instance, superimposed text is unreadable if the character size drops below a certain value. In this paper, we present a novel adaptation algorithm to scale and crop videos while preserving their semantic content. Semantic features in a shot are combined to select a suitable region to be resented in the adapted video.

Spontaneous Virtual Networks: On the road towards the Internet's Next Generation

Abstract Novel Internet applications demand global availability of complex services that can adapt dynamically to application requirements. At the same time, pervasive Internet usage and heterogeneous access technologies impose new challenges for service deployment. We present Spontaneous Virtual Networks (SpoVNet), a methodology that enables easy development of new services with transparent support for mobility, multi-homing, and heterogeneous environments. This article presents the overlay-based architecture of SpoVNet that supports the spontaneous deployment of new services as well as a seamless transition towards future networks. SpoVNet´s architecture offers support for the underlay aware adaptation of overlays by the use of cross-layer information. In the context of two exemplary services like a group communication service and an event service as well as two demanding applications – a realtime online game and a video streaming application – we illustrate how SpoVNet is of value in establishing services and applications for the Next Generation Internet.

Automatic lecture recording

We present our system for automatic lecture recording. In contrast to traditional lecture recording systems our approach aims to imitate a real camera team, consisting of multiple cameramen and a director, in order to make the recording more vivid. At first, we introduce the environment. Then, we present our approach, beginning with the director module, followed by the cameraman module and the sensor tools module, referring to the jobs of the respective human originals. The director is based on an Extended Finite State Machine, with transition conditions depending on input from sensor tools. The cameraman automatically controls iris, focus, etc., and also takes basic cinematographic rules into account. The video concludes with an example result of our virtual camera team of a real lecture. A video demo of our approach is available at [4].

Video color adaptation for mobile devices

A large number of videos cannot be visualized on mobile devices (e.g.,PDAs or mobile phones)due to an inappropriate color depth of the displays. Important details are lost if the color depth is reduced. A major challenge is the preservation of the semantic content in spite of this fact. In this paper, we present a novel adaptation algorithm to enable the playback of videos on color-limited mobile devices. Dithering algorithms diffuse the error to neighbor pixels and do not work very well for videos. We propose a non-linear transformation of luminance values and use textures in combination with edges to reduce the color depth in videos.

A Question Managing Suite for Automatic Lecture Recording.

Purpose – The purpose of this paper is describing the seamless integration of the question‐answer interaction into automatic lecture recordings (ALRs). This includes the design and implementation of the question management (QM) software for a virtual camera team.Design/methodology/approach – Coming from the human role model the interaction and its management to the virtual world is transferred and integrated it into a virtual camera team. All events are translated into sensor inputs which get processed by the virtual director and are used for the collaboration of the team in order to implement more complex cinematographic rules.Findings – It is found that it is possible to record the whole interaction, to record the original voice of the questioner out of an audience without handing out a microphone or forcing him/her to walk to one, and to record a video of the questioner while asking. So, it is easier to follow a lecture recording as more details are recorded automatically.Practical implications – First...