Publikationen

Zusammenfassung: The invention relates to a method for generating image information of an image of an image sequence using the image information of a first image. The object of providing a method for generating image information of an image of an image sequence so that a stroboscopic effect is avoided even in the case of varyingly fast movements of the image information and so that a clear display is still possible in the case of low speeds of the image information, is achieved in that the number of intermediate images is determined as a function of the value of the first movement measure and a weighting factor is calculated for each intermediate image.

Schlüsselwörter: active safety car project, automobiles, driver assistance systems, image processing, image segmentation, multisensor data fusion, object detection, object segmentation, sensor fusion, series production vehicles, traffic engineering computing

Zusammenfassung: Driver assistance systems support overstrained and affected drivers and become more and more essential for series-production vehicles. Object detection and segmentation is one of the most challenging research topics in this field. In order to warn the driver or automatically break before a potential collision, objects intersecting the path of the host vehicle have to be detected and classified. Most recently developed approaches are based on two dimensional image processing, sometimes in combination with a tracking algorithm associating detections in consecutive frames to one and the same object. Further robustness is achieved by multisensor data fusion, i.e. information by two or more different sensors (e.g. camera and radar data) are fused in order to get a much more reliable result. Another aspect for safety applications is communication between cars, which provides additional sensor locations and thus also requires data fusion technology. Two different approaches for data fusion are proposed and first results are presented.

Schlüsselwörter: channel bank filters, image motion analysis, image sequences, inverse perspective mapping, linear multidimensional filter theory, multidimensional velocity filter banks, parameterized filter bank, time invariant transfer function, video based motion analysis, video signal processing, world coordinate objects

Zusammenfassung: Linear multidimensional filter theory provides an elegant way to analyse movement within image sequences, i.e. to separate objects moving in different directions or at different speeds. Due to its time-invariant transfer function a single filter is restricted to specific motions, for which reason a consecutively parameterized filter bank is needed to differentiate a broader set of movement. In this paper, an introduction to velocity filtering is given and unwanted side-effects are discussed, i.e. spatio-temporal ringing and perspective distortion. As a practical example a traffic scene is analysed by means of inverse perspective mapping followed by a velocity filter bank.

Schlüsselwörter: Explicit discretization, Iterative learning control, nD linear systems, PDEs

Schlüsselwörter: 1D filter, 1D signal processing, antialiasing, antialiasing method, eye, human eye, image sampling, image sequence, image sequences, sampling theorem, video signal generation, video signal processing, visual perception, wagon-wheel effect

Zusammenfassung: In this paper a new method of avoiding aliasing effects in synthetically generated video is presented. In other words, aim is to remove aliasing effects that disturb visual perception of the synthetically generated image sequence by the human eye. In general, aliasing occurs if the widely known sampling theorem is not met. In the field of video applications, more often than not the limiting factor leading to these disturbing effects is the temporal sampling rate (a.k.a. "frame rate"). The standard approach known from 1-D signal processing applications, i.e. increasing the sampling rate, is effective but very hardware-expensive as it introduces additional frames that have to be processed by the underlying system. In contrast, the proposed method uses a cheap 1-D filter in space-direction to achieve the same aliasing-free result.

Schlüsselwörter: antialiasing, antialiasing approach, blind spot warning systems, camera signal, cameras, computational power, driver assistance systems, driver information systems, improved motion based object detection, linear filter, linear shift invariant, low temporal resolution, object detection

Zusammenfassung: In this paper a new anti-aliasing approach for motion-based object detection using linear shift invariant (LSI) filters is presented. Mainly originating from the field of signal processing, LSI-filter-based motion detection has been topic of research for a long time, though due to low computational power of contemporary computers the developed systems have been unfeasible for application in mass products like driver assistance systems. However, recent progress in hardware in conjunction with decreasing costs makes using linear filters a very interesting alternative of increasing performance of common approaches. One of the most important factors falsifying object detection results obtained using linear shift invariant (LSI) is aliasing. This is mostly caused by the low temporal resolution of the camera signal which leads to the fact that the sampling theorem does not hold for objects moving at high speed in the image plane. In general, aliasing errors cannot be removed after sampling. Under certain conditions, however, their impact on the filter result can be successfully decreased using the approach presented in this paper. The applicability of the new approach is demonstrated using scenes recorded by a camera installed in a blind spot warning system.