Difference between revisions of "Image Calculator: OR"

Latest revision as of 19:14, 22 February 2012

OR

If the pixel value from a chosen pixel in Image A equals zero, then the result pixel value is set equal to the corresponding Image B pixel value. Otherwise, the result pixel value is the same as for the Image A (i.e. stays unchanged).

Result=Image B, if Image A=0;
otherwise, Result=Image A.

XOR

It overlays two images together, but then clears the area that is overlapped back to transparency. If both Image A and Image B pixel values are nonzero, then the result image is set to zero. If both Image A and Image B pixel values are zero, then the result image remains zero. If only one of Image A and Image B is nonzero, then the result retains or assumes the nonzero value.

Subtract

Subtracts the pixel values of Image B from the corresponding pixel values of Image A.

Advanced math options

Abs

Generates the absolute value of the active image or selection.

Exp

Applies the function f(p) = exp(p) to each pixel (p) in the image or selection. For RGB images, this function is applied to all three color channels.

Ln

Applies the function f(p) = ln(p) to each pixel (p) of the image or selection. For RGB images, this function is applied to all three color channels.

Log

Applies the function f(p) = log(p) to each pixel (p) in the image or selection. For RGB images, this function is applied to all three color channels.

Pow

The function pow (x,y) produces a value of x raised to the power of y, e.g., pow(2,3) gives 8. For RGB images, this function is applied to all three color channels. In clip mode, for RGB images with byte values, results greater than 255 are set to 255. In promote destination image mode, the image will be promoted to ARGB_USHORT and capable of storing color values of up to 65535.

Sin, cos, tan

Apply the functions sin(p), cos(p), and tan(p) to each pixel (p) of the image or selection. For RGB images, the chosen function is applied to all three color channels.

Applying the Image Calculator to images

To run this algorithm, complete the following steps:

1 Open at least two images. The images must have the same dimensions.
2 Select Utilities >Image Calculator. The dialog box opens. See Figure 35.
3 Use the Operator list box to select the math operator (Add, AND, Average, etc.).
4 Use the Image B list box to select Image B.
5 Check the Clip option if you want to clamp result data to the bounds of the input image type. Check the Promote option to promote image type so that the range of the result fits into the new image type. Refer to "clip mode" and "promotion mode" .
6 Click OK. The algorithm begins to run.
7 Depending on whether you selected New Image or Replace Image A, the result appears in a new window or replaces the image to which the algorithm was applied.

Image Calculator: Advanced image calculator options