滤波是一种用于修正或增强图像的技术。例如,您可以对图像进行滤波以强调某些特征或删除其他特征。用滤波实现的图像处理运算包括平滑、锐化和边缘增强。
图像区域分析器 | Browse and filter connected components in an image |
在经过空间滤波的图像中,每个输出像素的值是相邻输入像素的加权和。权重由称为卷积核或滤波器的矩阵提供。
Filter Grayscale and Truecolor (RGB) Images using imfilter Function
This example shows how to filter an image with a 5-by-5 averaging filter containing equal weights.
Filter Images Using Predefined Filter
This example shows how to create a type of special filter called an unsharp masking filter, which makes edges and detail in an image appear sharper.
imfilter Boundary Padding Options
When a portion of the convolution or correlation kernel extends past the edge of an image, you can extrapolate image values by zero-padding the image or by replicating boundary pixels.
噪声是指在图像采集或传输过程中出现的像素值的随机误差。去除噪声可以提高图像质量。
此示例说明如何使用不同强度的高斯平滑滤波器来对图像进行模糊处理。该示例包括各向同性和各向异性高斯滤波。
Reduce Noise in Image Gradients
This example shows how to reduce noise associated with computing image gradients.
What is Guided Image Filtering?
Guided image filtering performs edge-preserving smoothing on an image. It uses the content of a second image, called a guidance image, to influence the filtering.
Perform Flash/No-flash Denoising with Guided Filter
This example shows how to reduce noise from an image while using a guidance image to preserve the sharpness of edges.
Segment Thermographic Image after Edge-Preserving Filtering
This example shows how to segment a hot object from the background in a thermographic image.
Integral images are a quick way to represent images for filtering. In an integral image, the value of each pixel is the summation of the pixels above and to the left of it.
Apply Multiple Filters to Integral Image
This example shows how to smooth an image by different amounts by applying box filters of varying sizes to the integral image.
Design Linear Filters in the Frequency Domain
You can design filters that modify the frequency content of images. Filtering in the frequency domain is often faster than filtering in the spatial domain.