This paper addresses the task of automating the visual inspection of a strip of plastic by a vision system based on a line scan camera. The defects on the strip are characterized by a local variation in the reflectanc...
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This paper addresses the task of automating the visual inspection of a strip of plastic by a vision system based on a line scan camera. The defects on the strip are characterized by a local variation in the reflectance properties of the surface to be inspected. There are efficient methods, even with variations in illumination, to highlight the defects. Usually these methods used high-pass filters, to enhance the edges of the defects. In the presence of noise the performance of these filters tends to decrease. Also, before the use of a high-pass filter it is necessary to apply a low-pass filter to smooth the noise in the line image. But in the case of poor contrast defects these methods are inefficient. We propose to take advantage of a new filter which has been developed in our laboratory and which optimizes the edge detection of the defect in any case. The performance of this new filter are demonstrated with real images and with different kind of defects.
In late 1996, the Federal communications Commission ruled the United States would migrate to a digital television broadcasting system. The Commission chose the Grand Alliance transmission scheme and left the picture s...
In late 1996, the Federal communications Commission ruled the United States would migrate to a digital television broadcasting system. The Commission chose the Grand Alliance transmission scheme and left the picture scanning format to the marketplace. High Definition video, at 1920 times 1080 pixels, interlaced scanning, at a nominal 60 Hertz field rate is one format in the infamous Table 3 of the ATSC document and FCC ruling. This picture format is also well on the way to becoming a universal format. — A new series of digital systems, conforming to the interlaced scanning format of SMPTE 274M- 1995 were recently introduced by Sony. This paper deals with the architecture, enabling technologies, and capabilities of a live and post production vision mixer from this family of equipment. — A modern, digital, high definition vision mixer, and associated digital effects and editing equipment, must provide producers, directors, and the artistic and technical staff employing them with similar capabilities as existing standard definition equipment—the visual effects expected by a sophisticated audience. These requirements are detailed in this paper and the vision mixer described is compared to similar standard definition devices. — The capabilities of the switcher resulted in an architecture for crosspoints, mix effects systems, key and video processing, control and external interfaces. Operational and maintenance aspects are also key factors in an architecture and include considerations for size, mass, power consumption and heat loads. Picture size and shape may change but control room and remote broadcast vehicle designs dictate limitations on these specifications. Trade-offs in capability and architecture are enumerated. — The data rates employed in HDTV (more than 5 times the rate of SMPTE 125M and SMPTE 259M) required additional new technologies, including the development of a series of Application Specific Integrated Circuits which perform the same functions employed i
We utilize speech information to improve the quality of audio-visualcommunications such as video telephony and videoconferencing. We show that the marriage of speech analysis and imageprocessing can solve problems r...
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We utilize speech information to improve the quality of audio-visualcommunications such as video telephony and videoconferencing. We show that the marriage of speech analysis and imageprocessing can solve problems related to lip synchronization. We present a technique called speech-assisted frame-rate conversion, and apply it to coding of talking head video. Demonstration sequences are presented. Extensions and other applications are outlined.
We introduce in the present paper a fast 3D fractal encoding method based on tree compression and achieving good compression ratio at very low bit rate. The algorithm is also open to transposition on the space of wave...
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ISBN:
(纸本)0819421030
We introduce in the present paper a fast 3D fractal encoding method based on tree compression and achieving good compression ratio at very low bit rate. The algorithm is also open to transposition on the space of wavelet coefficients.
In most IFS based image coding schemes, the domain blocks codebook searched is independent from the input image, identical for all range blocks of the same size, and non optimized. In order to get a good match between...
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ISBN:
(纸本)0819421030
In most IFS based image coding schemes, the domain blocks codebook searched is independent from the input image, identical for all range blocks of the same size, and non optimized. In order to get a good match between range and domain blocks, a huge codebook is used, which is both inefficient in terms of computational complexity and output bit rate. We propose to design an optimal reduced codebook for the whole image thanks to a geometrical analysis of the basic scheme. We then compare this method with a 'local' codebook method, which leads us to some conclusions about the differences between IFS and vectorial quantization (VQ) based coding schemes.
The reconstruction of 3D road centerlines becomes a physical problem of solving an energy- minimizing 3D B-splines shape model. The reconstruction is described as a process whereby a 3D road centerline shape model is ...
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ISBN:
(纸本)0819421030
The reconstruction of 3D road centerlines becomes a physical problem of solving an energy- minimizing 3D B-splines shape model. The reconstruction is described as a process whereby a 3D road centerline shape model is deformed gradually, driven by forces arising from object space (internal energy) and image sequences (external energy). Recent test results demonstrate that this approach functions reliably even in situations where navigation errors exist and the road condition is far from ideal.
In motion-compensated processing of image sequences, e.g. in frame interpolation, frame rate conversion, deinterlacing, motion blur correction, image sequence restoration, slow-motion replay, etc., the knowledge of mo...
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ISBN:
(纸本)0819421030
In motion-compensated processing of image sequences, e.g. in frame interpolation, frame rate conversion, deinterlacing, motion blur correction, image sequence restoration, slow-motion replay, etc., the knowledge of motion is essential. In these applications motion information has to be determined from the image sequence. Most motion estimation algorithms use only a simple motion model, and assume linear constant speed motion. The contribution of our paper is the development of an algorithm for modeling and estimation of accelerated motion trajectories, based on a second order motion model. This model is more general and much closer to the real motion present in natural image sequences. The parameters of the accelerated motion are determined from two consecutive motion fields, that has been estimated from three consecutive image frames using a multiresolution pel-recursive Wiener-based motion estimation algorithm. The proposed algorithm was successfully tested on artificial image sequences with synthetic motion as well as on natural real-file videophone and videoconferencing sequences in a frame interpolation environment.
A problem of motion segmentation in RGB image sequence is addressed. An algorithm proposed is based on local motion modeling and pixel labeling approach. An information vector used for labeling consists of six compone...
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ISBN:
(纸本)0819421030
A problem of motion segmentation in RGB image sequence is addressed. An algorithm proposed is based on local motion modeling and pixel labeling approach. An information vector used for labeling consists of six components; three color components and three differences of colors. To develop the labeling algorithm a statistical model of motion sequence, which uses a six-variate Gaussian distribution, is chosen. Moreover, the use of a hidden Markov random field (MRF) framework is proposed in order to carry out the segmentation more accurately. The experimental results of the application of the method to an RGB sequence showing a woman's turning head are included and discussed.
An image compression method based on wavelet transforms and the human visual system (HVS) is presented in this paper. In the proposed method, we emphasize on the issue of designing a quantizer for wavelet transform co...
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A postprocessing algorithm is proposed to reduce the blocking artifacts of joint photographic experts group (JPEG) decompressed images. The reconstructed images from JPEG compression produce noticeable image degradati...
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ISBN:
(纸本)0780332598
A postprocessing algorithm is proposed to reduce the blocking artifacts of joint photographic experts group (JPEG) decompressed images. The reconstructed images from JPEG compression produce noticeable image degradation near the block boundaries, in particular, for highly compressed images because each block is transformed and quantized independently. The reduction of these blocking effects has been an essential issue for high quality visualcommunications. The proposed postprocessing algorithm reduces these blocking artifacts efficiently. A comparison study between the proposed algorithm and other postprocessing algorithms is made by computer simulation with several JPEG images. These simulation results show that the proposed algorithm reduces the blocking artifacts significantly in the subjective and objective views.
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