Posted by
R. C. on
URL: http://imagej.273.s1.nabble.com/Calibrating-density-and-creating-calibrated-image-tp3692091p3692093.html
You can use something like this: (first convert to 32bit image)
// Radiochromic film calibration
// A. Perez Rozos - Enero 2009
// H. Virgen de la Victoria. Malaga. spain
// -------------------------------------------------------
macro "Calibration" {
// a0...a3 are the coeficients of the calibration 3th degree polyn.
a0=2191.9
a1=-0.1411
a2=0.000003206
a3=-0.0000000000252
w1 = getWidth(); h1 = getHeight();
for (i=0; i<w1; i++) {
for (j=0;j<h1; j++) {
vpixel=getPixel(i,j);
cpixel=a0 + a1 * vpixel + a2 *vpixel*vpixel +a3 *vpixel*vpixel*vpixel;
// Negative values are equaled to 0
if (cpixel<0) cpixel=0;
setPixel(i,j,cpixel);
};
showProgress((i/w1));
};
print("Calibration curve applied - EBT Junio de 2008");
};
Alberto Perez
Medical Physicist
Hospital Universitario Virgen de la Victoria
Malaga. Spain
[hidden email]
2009/6/17 Michael A. Miller <
[hidden email]>
- Mostrar texto citado -
>>>>> "Diana" == Diana <
[hidden email]> writes:
> I am working with autoradiography images - these are grey
> scale and need to be calibrated to uCi using images of
> radioactive standards. I know how to make and apply
> calibrations using the calibrate function and a rodbard
> curve.
> My question: is it possible to CONVERT the original image
> (grey scale) into a calibrated image where each pixel is
> converted into the new (calibrated) value. In other words,
> i want to create and save this new calibrated image as a
> map of uCi.
You can apply your calibration with the image math functions
available in the Process-Math->... menu. If the original image
is integer data, make sure to convert the image to 32 bit
floating point values first (using Image->Type->32 bit).
If you save the image as raw values (or tiff), it can be loaded
into another program.
Mike
--
Michael A. Miller
[hidden email]
Department of Radiology, Indiana University School of Medicine