NAME

imfunction -- Apply a function to the image pixel values

USAGE

imfunction input output function

PARAMETERS

input

The input image list.

output

Output image list. The number of output images must match the number of input images. If the output image list equals the input image list the input images are overwritten.

function

Function to be applied to the input pixels. The options are:

log10

Take the logarithm to base 10 of an image. Negative and zero-valued pixels will be asigned the value -MAX_EXPONENT.

alog10

Taken the antilogarithm to base 10 of the image. Positive out-of-bounds pixel values will be assigned the value MAX_REAL, negative out-of-bounds pixel values will be assigned the value 0.0.

ln

Take the natural logarithm of an image. Negative and zero-valued pixels will be assigned the value - ln (10.) * MAX_EXPONENT.

aln

Take the antilogarithm to base e of an image. Positive out-of-bounds pixel values will be assigned the value MAX_REAL, negative out-of-bounds pixel values will be assigned the value 0.0

sqrt

Take the square root of an image. Negative pixel values will be assigned the value 0.0.

square

Take the square of an image.

cbrt

Take the cube root of an image.

cube

Take the cube of an image.

abs

Take the absolute value of an image.

neg

Take the negative of an image.

cos

Take the cosine of an image.

sin

Take the sine of an image.

tan

Take the tangent of an image.

acos

Take the arc-cosine of an image. The output pixels will lie between 0.0 and PI.

asin

Take the arc-sine of an image. The output pixels will lie between -PI/2 and +PI/2.

atan

Take the arc-tangent of an image. The output pixels will lie between -PI/2 and +PI/2.

hcos

Take the hyperbolic cosine of an image. Positive or negative out-of-bounds pixels will be assigned the value MAX_REAL.

hsin

Take the hyberbolic sine of an image. Positive and negative out-of-bounds pixel values will be assigned the values MAX_REAL and -MAX_REAL respectively.

htan

Take the hyperbolic tangent of an image.

reciprocal

Take the reciprocal of an image. Zero-valued pixels will be assigned the output value 0.0

verbose = yes

Print messages about actions taken by the task?

DESCRIPTION

The selected function function is applied to the pixel values of all the input images input to create the pixel values of the output images output . The number of output images must equal the number of input images. If the output image name is the same as the input image name the input image will be overwritten.

If the input image is type real or double the output image will be of type real or double respectively. If the input image is type ushort then the output image will be type real. If the input image is one of the remaining integer data types, then the output image will be type real, unless function is "abs" or "neg", in which case the output data type will be the same as the input data type.

Values of the machine dependent constants MAX_REAL and MAX_EXPONENT can be found in the file "hlib$mach.h".

EXAMPLES

1. Take the logarithm of the pixel values of images in1 and in2 and write the results to out1 and out2.

    cl> imfunction in1,in2 out1,out2 log10

SEE ALSO

imarith,imreplace