imadd (Image Processing Toolbox User's Guide)

Image Processing Toolbox User's Guide

Add two images, or add a constant to an image

Syntax

```
Z = imadd(X,Y)
```

Description

Z = imadd(X,Y) adds each element in array X with the corresponding element in array Y and returns the sum in the corresponding element of the output array Z. X and Y are real, nonsparse numeric arrays with the same size and class, or Y is a scalar double. Z has the same size and class as X, unless X is logical, in which case Z is double.

If X and Y are integer arrays, elements in the output that exceed the range of the integer type are truncated, and fractional values are rounded.

Note On Intel architecture processors, imadd can take advantage of the Intel Performance Primitives Library (IPPL), thus accelerating its execution time. IPPL is activated if arrays X, Y, and Z are of class logical, uint8, or single and are of the same class. IPPL is also activated if Y is a double scalar and arrays X and Z are uint8, int16, or single and are of the same class.

Examples

Add two uint8 arrays. Note the truncation that occurs when the values exceed 255.

X = uint8([ 255 0 75; 44 225 100]);
Y = uint8([ 50 50 50; 50 50 50 ]);
Z = imadd(X,Y)
Z =

   255    50   125
    94   255   150

Add two images together and specify an output class.

I = imread('rice.png');
J = imread('cameraman.tif');
K = imadd(I,J,'uint16');
imshow(K,[])

Add a constant to an image.

I = imread('rice.png');
J = imadd(I,50);
subplot(1,2,1), imshow(I) 
subplot(1,2,2), imshow(J)

imabsdiff imadjust