Keyframe Extraction in Endoscopic Video

In medical endoscopy more and more surgeons archive the recorded video streams in a long-term storage. One reason for this development, which is enforced by law in some countries, is to have evidence in case of lawsuits from patients. Another more practical reason is to allow later inspection of previous procedures and also to use parts of such videos for research and for training. However, due to the dramatic amount of video data recorded in a hospital on a daily basis, it is very important to have good preview images for these videos in order to allow for quick filtering of undesired content and for easier browsing through such a video archive. Unfortunately, common shot detection and keyframe extraction methods cannot be used for that video data, because these videos contain unedited and highly similar content, especially in terms of color and texture, and no shot boundaries at all. We propose a new keyframe extraction approach for this special video domain and show that our method is signi�cantly better than a previously proposed approach

Context-Aware UPnP-AV Services for Adaptive Home Multimedia Systems

Recommended by Harald Kosch One possibility to provide mobile multimedia in domestic multimedia systems is the use of Universal Plug and Play Audio Visual (UPnP-AV) devices. In a standard UPnP-AV scenario, multimedia content provided by a Media Server device is streamed to Media Renderer devices by the initiation of a Control Point. However, there is no provisioning of context-aware multimedia content customization. This paper presents an enhancement of standard UPnP-AV services for home multimedia environments regarding context awareness. It comes up with context profile definitions, shows how this context information can be queried from the Media Renderers, and illustrates how a Control Point can use this information to tailor a media stream from the Media Server to one or more Media Renderers. Moreover, since a standard Control Point implementation only queries one Media Server at a time, there is no global view on the content of all Media Servers in the UPnP-AV network. This paper also presents an approach of multimedia content integration on the Media Server side that provides fast search for content on the network. Finally, a number of performance measurements show the overhead costs of our enhancements to UPnP-AV in order to achieve the benefits

Fast and Flexible Video Content Browsing based on H.264/AVC Features [Demonstration]

ABSTRACT We present a video content browsing tool which is supposed to be used for two purposes: (1) efficiently searching a certain scene within a long video sequence and (2) quickly identifying videos out of interest. Instead of a complex user interface with many features we rather use a simple but flexible player-like interface which can, however, support the user on taking advantage of his/her knowledge about the content semantics. The content analysis is based on some simple features which can be extracted from compressed data of H264/AVC and, thus, allow very fast analysis. An early user study has shown encouraging results

Fast Segmentation of H.264/AVC Bitstreams for On-Demand Video Summarization.

Abstract. Video summarization methods need fast segmentation of a video into smaller units as a first step, especially if used in an on-demand fashion. We propose an efficient segmentation algorithm for H.264/AVC bitstreams that is able to segment a video in appr. 10% of the time required to decode the video. This is possible because our approach uses features available after entropy-decoding (which is the very first stage of the decoding process) only. More precisely, we use a combination of two features, especially appropriate to H.264/AVC, with different characteristics in order to decide if a new segment starts or not: (1) L1-Distance based partition histograms and (2) ratio of intra-coded macroblocks on a per-frame basis. Our results show that this approach performs well and works for several different encoders used in practice today