共查询到16条相似文献,搜索用时 140 毫秒
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针对高斯模板用于图像旋转时,使图像产生模糊的问题,提出细粒度动态单像素模板算法.根据图像小邻域局部相关性原理,将当前像素分割为5×5的子像素,对每一个子像素求得一个模板.用当前像素的这25个模板之一代替高斯模板进行图像旋转,消除了高斯模板旋转图像时产生模糊的问题.该算法旋转图像的质量与双线性插值算法相近,且具有更高的计算性能. 相似文献
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为提高旋转图像的质量和性能,提出了一种亚像素圆模板算法。在假设图像是连续的前提下进行逆向旋转变换;通过像素网格状分割选取亚像素圆模板的圆心;用亚像素圆模板(直径等于像素边长)进行离散化。邻域像素被圆模板覆盖的面积与圆面积的比值Rs,相应像素的颜色值Cs,旋转后像素的颜色值等于Rs和Cs的卷积。实验表明该算法图像旋转效果好于最近邻点插值和高斯模板算法,连续性接近双线性插值,计算性能明显高于双线性插值和高斯模板。 相似文献
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旋转图像的质量和性能是需要权衡的一个问题,提出一种细粒度亚像素圆模板算法.通过像素网格状5x5分割选取圆模板的圆心.邻域像素被圆模板覆盖的面积与圆面积的比值Rs,相应像素的颜色值Cs,旋转后像素的颜色值等于Rs和Cs的卷积.实验表明该算法图像旋转质量好于最近邻点插值和高斯模板算法,清晰度和连续性接近双线性插值,计算性能明显优于双线性插值. 相似文献
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快速离散化双线性插值算法 总被引:5,自引:0,他引:5
双线性插值算法在数字图像处理中有广泛的应用.它具有比最近邻点法更好的连续性,但计算速度慢.为提高其计算速度,提出了离散化双线性插值算法.把像素分割成子像素,用双线性插值函数计算子像素中心坐标处的像素值,可以得到每一个子像素的卷积函数C,用C来代替双线性插值函数.理论分析表明离散化算法减少了加法和乘法的浮点运算次数.通过图像旋转实验表明该算法与双线性插值算法相比计算速度有较大的提高,连续性略有损失,图像质量基本相同. 相似文献
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基于高斯模板的图象旋转算法 总被引:3,自引:2,他引:3
图象旋转是图象处理中的一个基本操作,根据图象在邻近区域内连续的特点,该文提出一种基于高斯模板的图象旋转算法。实验结果表明,该算法能较好地消除图象旋转所产生的锯齿现象,图象多次旋转后失真较少,与最近插值和双线性插值相比具有较好的性能。 相似文献
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针对现有图像插值算法只考虑原始图像像素的问题,提出了一种兼顾原始图像与插值图像的红外图像插值算法。该算法将原始图像中的像素映射至插值图像中,然后使用双线性插值算法从原始图像中恢复插值像素,最后通过插值图像中已有的像素对插值像素进行加权修复。实验结果表明,所提算法的插值效果优于经典的图像插值算法,能有效避免锯齿和模糊现象的发生。 相似文献
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为了在滤除椒盐噪声的同时尽可能地保留图像细节,提出了一种基于曲率的双线性插值滤波算法。该算法鉴于双线性插值的低通滤波固有特性,引入像素值的变化以构造类双线性插值模型;为了获得相邻像素的方向趋势,引入曲率信息;以曲率信息为参考,选择最接近原始图像变化规律的方向进行双线性插值滤波。实验结果表明,该方法在滤除噪声的同时有效地保留了图像的细节,且滤波效果优于传统的滤波算法。 相似文献
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A motion deblurring algorithm is proposed to enhance the quality of restoration based on the point spread function (PSF) identification in frequency spectrum. An improved blur angle identification algorithm characterized by bilateral-piecewise estimation strategy and the membership function method is presented by formulating the edges of the central bright stripe. Subsequently, the subpixel level image generated with bilinear interpolation is employed in the blur length estimation by calculating the distance between two adjacent dark strips. Through comparison with the existing algorithms, experimental results demonstrate that the proposed PSF estimation scheme could not only achieve higher accuracy for the blur angle and the blur length, but also produce more impressive restoration results. Furthermore, the robustness of our method is also validated in different noisy situations. 相似文献
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Sub-pixel precision image matching for measuring surface displacements on mass movements using normalized cross-correlation 总被引:1,自引:0,他引:1
This study evaluates the performance of two fundamentally different approaches to achieve sub-pixel precision of normalised cross-correlation when measuring surface displacements on mass movements from repeat optical images. In the first approach, image intensities are interpolated to a desired sub-pixel resolution using a bi-cubic interpolation scheme prior to the actual displacement matching. In the second approach, the image pairs are correlated at the original image resolution and the peaks of the correlation coefficient surface are then located at the desired sub-pixel resolution using three techniques, namely bi-cubic interpolation, parabola fitting and Gaussian fitting. Both principal approaches are applied to three typical mass movement types: rockglacier creep, glacier flow and land sliding. In addition, the influence of pixel resolution on the accuracies of displacement measurement using image matching is evaluated using repeat images resampled to different spatial resolutions. Our results show that bi-cubic interpolation of image intensity performs best followed by bi-cubic interpolation of the correlation surface. Both Gaussian and parabolic peak locating turn out less accurate. By increasing the spatial resolution (i.e. reducing the ground pixel size) of the matched images by 2 to 16 times using intensity interpolation, 40% to 80% reduction in mean error in reference to the same resolution original image could be achieved. The study also quantifies how the mean error, the random error, the proportion of mismatches and the proportion of undetected movements increase with increasing pixel size (i.e. decreasing spatial resolution) for all of the three mass movement examples investigated. 相似文献
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