Complement image


IM2 = imcomplement(IM)
gpuarrayIM2 = imcomplement(gpuarrayIM)


IM2 = imcomplement(IM) computes the complement of the image IM. IM can be a binary, grayscale, or RGB image. IM2 has the same class and size as IM.

In the complement of a binary image, zeros become ones and ones become zeros; black and white are reversed. In the complement of an intensity or RGB image, each pixel value is subtracted from the maximum pixel value supported by the class (or 1.0 for double-precision images) and the difference is used as the pixel value in the output image. In the output image, dark areas become lighter and light areas become darker.

gpuarrayIM2 = imcomplement(gpuarrayIM) computes the complement of the image on a GPU. The input image gpuarrayIM and the return values are gpuArrays. gpuarrayIM2 is a gpuArray with the same underlying class and size as gpuarrayIM. This syntax requires the Parallel Computing Toolbox™.

Code Generation support: Yes.

MATLAB Function Block support: Yes.


Create the complement of a uint8 array

X = uint8([ 255 10 75; 44 225 100]);
X2 = imcomplement(X)
X2 =
     0   245   180
   211    30   155

Reverse black and white in a binary image

bw = imread('text.png');
bw2 = imcomplement(bw);

Create the complement of an intensity image

I = imread('glass.png');
J = imcomplement(I);
imshow(I), figure, imshow(J)

Create the complement of an intensity image on a GPU

 I = gpuArray(imread('glass.png'));
 J = imcomplement(I);
 figure, imshow(I), figure, imshow(J)

More About

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Code Generation

This function supports the generation of C code using MATLAB® Coder™. For more information, see Code Generation for Image Processing.

imcomplement does not support int64 and uint64 data types

MATLAB Function Block

You can use this function in the MATLAB Function Block in Simulink.


  • If IM is a grayscale or RGB image of class double, you can use the expression 1-IM instead of this function. If IM is a binary image, you can use the expression ~IM instead of this function.

Introduced before R2006a

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