Sharpening filter for images with automatic adaptation to image type
    1.
    发明授权
    Sharpening filter for images with automatic adaptation to image type 失效
    用于自动适应图像类型的图像锐化滤镜

    公开(公告)号:US5822467A

    公开(公告)日:1998-10-13

    申请号:US773428

    申请日:1996-12-27

    CPC分类号: H04N1/4092

    摘要: A method of filtering images with a filter that is dependent on image type. For binary images, a fixed Laplacian filter is used for all pixels. For non-binary images, an automatic level-sensitive Laplacian filter is used. For non-binary images, Laplacian filter coefficients and normalization divisors are made a function of intensity on a pixel by pixel basis. Pixels indicating a high intensity may be greatly changed by neighboring pixels. Pixels indicating a low intensity receive relatively little or no filtering. In a specific example embodiment, the intensity range is divided to bands, with a different filter for each band. The resulting images are visually sharpened (edge enhanced) with very little impact in darker areas of the image.

    摘要翻译: 使用依赖于图像类型的过滤器过滤图像的方法。 对于二进制图像,固定的拉普拉斯滤波器用于所有像素。 对于非二进制图像,使用自动电平敏感的拉普拉斯滤波器。 对于非二进制图像,将拉普拉斯滤波器系数和归一化因数作为逐个像素的强度函数。 指示高强度的像素可能被相邻像素极大地改变。 指示低强度的像素接收相对较少或不进行滤波。 在具体的示例性实施例中,强度范围被划分为带,每个频带具有不同的滤波器。 所得到的图像在图像的较暗区域中以非常小的影响被视觉上锐化(边缘增强)。