imfilter函数是一种计算机函数，也叫做实现线性空间滤波函数，功能是对任意类型数组或多维图像进行滤波，函数形式是B = imfilter(速半地调省首攻够A,H)。

• 中文名称 imfilter函数
• 外文名称 imfilter
• 函数形式 B = IMFILTER()
• 注意事项 To disable IPPL
• 函数功能 对数组或多维图像进行滤波

imfilter函数解释

　　用法:B = imfilter(A,H)

　　B = i何领mfilter(来自A,H,option1,option2,...)

　　或写作g = imfilter(f, w, fil消调有剂统解tering_mode, 360百科boundary_options, size_options)其中，f为输入图像，w为滤波掩模，g为滤波后图像。fil绍也苏tering_mode用于指定在滤波过程雨例殖中是使用"相关"还是"卷积"。利牛配曲织族击析boundary_options用于处理边界抓物事联曾输国针课充零问题，边界的大小由滤波器的大小确定。具体参数选项见下表:

　　举例:originalRGB = imread('peppers.png');

　　imshow(伤二甲异序胞织originalRGB)

　　h = fspecia办白l('motion', 50, 45);%创建一个滤波器

　　filteredRGB = imfilter(originalRGB, h);

　　figure, imshow(filteredRGB)

函数形式

　　B = IMFILTER(A,H,OPTION1,OPTION2,...) performs multidimensional

李百教名官特感控乐　　filtering according to the specified options. Option arguments can

　　have the following values:

　　- Boundary options

　　X Input array values ou起础怀香tside the bou倒物反回陈看呀赶nds of the array

　办　are impl节儿前口火题触以但去icitly assum吸司是新球推ed to have the value X. When no

　　boundary option is specified, IMFILTER uses X = 0.

　　'symmetric' Input array values outside the bounds of the array

　　are computed by mirror-reflecting the array across

　　the array border.

　　'replicate' Input array values outside the bounds of the array

　　are assumed to equal the nearest array border

　　value.

　　'circular' Input array values outside the bounds of the array

　　are computed by implicitly assuming the input array

　　is periodic.

　　- Output size options

　　(Output size options for IMFILTER are analogous to the SHAPE option

　　in the functions CONV2 and FILTER2.)

　　'same' The output array is the same size as the input

　　array. This is the default behavior when no output

　　size options are specified.

　　'full' The output array is the full filtered result, and so

　　is larger than the input array.

　　- Correlation and convolution

　　'corr' IMFILTER performs multidimensional filtering using

　　correlation, which is the same way that FILTER2

　　performs filtering. When no correlation or

　　convolution option is specified, IMFILTER uses

　　correlation.

　　'conv' IMFILTER performs multidimensional filtering using

　　convolution.

注意事项

　　Notes

　　-----

　　On some Intel Architecture processors, IMFILTER can take advantage of the

　　Intel Performance Primitives Library (IPPL), thus accelerating its execution

　　time. IPPL is activated only if A and H are both two dimensional and A is

　　uint8, int16 or single.

　　When IPPL is used, imfilter has different rounding behavior on some

　　processors. Normally, when A is an integer class, filter outputs such as

　　1.5, 4.5, etc., are rounded away from zero. However, when IPPL is used,

　　these values are rounded toward zero. This behavior may change in a future

　　release.

　　To disable IPPL, use this command:

　　iptsetpref('UseIPPL',false)

举例

　　Example

　　-------------

　　originalRGB = imread('peppers.png');

　　h = fspecial('motion',50,45);

　　filteredRGB = imfilter(originalRGB,h);

　　figure, imshow(originalRGB), figure, imshow(filteredRGB)

　　boundaryReplicateRGB = imfilter(originalRGB,h,'replicate');

　　figure, imshow(boundaryReplicateRGB)