Summary: | 碩士 === 國立交通大學 === 電機資訊學院碩士在職專班 === 93 === In recent years, progressive scanning output devices have becoming very popular. However, many video sources are still using the conventional interlaced TV format. Therefore, the de-interlacing technique which converts interlaced picture to progressive picture is essential. It has been used widely in various kinds of commercial products. But the conventional simple de-interlacing method does not provide good picture quality particularly in the moving areas.
The main theme of this thesis is an integrated de-interlacing system, which incorporates several known and improved techniques in a nice manner to produce good de-interlaced image quality. We first develop an accurate motion detector that classifies image regions into stationary, low-motion, and high-motion categories. The simple field merging method is applied to the stationary regions. The edge line average interpolation method is applied to the slow-motion regions. Finally, the motion-compensated interpolation is applied to the high-motion regions. In addition, hierarchical motion estimation and motion vector smoothing techniques are employed to enhance the quality of estimated motion vectors. Our computer simulation shows that the subjective image quality is improved by using the proposed scheme. Also, its PSNR measures are better than the conventional spatial or temporal interpolation schemes.
In addition, in real applications, interlaced TV pictures are often derived from the films at different frame rate. To achieve a good picture quality, a film detector and an associated image enhancement scheme are added to our de-interlacing system. In this proposed system architecture, we can recover the 3:2 pull down format. With image enhancement algorithm after de-interlacing, the subjective image quality is generally improved.
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