Posted by
Divya Rathore on
Oct 16, 2006; 1:48am
URL: http://imagej.273.s1.nabble.com/measurements-using-MRI-jpg-images-tp3701304p3701310.html
> On Sunday 15 October 2006 06:43, John Dufton wrote:
>> I have a question regarding measurements on mri images.
>> I have saved a number of images as jpg images. The measurements on
>> these
>> jpg images do not seem to correspond to measurements on the workstation.
>
> Hi,
> Jpeg compressed images should not be used for serious imaging purposes.
> The compression in the jpegs is lossy, so I guess that you may be
> measuring some amount of artifacts rather than the data.
>
> Gabriel
>
I completely second Gabriel. Jpeg is not the format for serious
quantitations in MRI.
In case you are using Windows, you can try 'HeaderCorrection.exe' program
that I have made to chop off the header data in DICOMs and save image data
as separate files. Later use ImageJ to read them as Raw files.
The link is:
http://home.iitk.ac.in/~rksr/softwares/Step 1: choose single/multiple file(s)
Step 2: choose output folder where you want the data to be saved.
Step 3: You would be knowing the width and height of the data. Feed it.
DICOM is normally 2 byte data. So 'Bytes per pixel' remain 2.
Step 4: Optional. Can be zero. Default is 8432.
Press Process button and you are through.
Later use ImageJ to open the generated files.
File >> Import >> Raw >> Selelct the output folder as in Step 2.
In the Dialog that shows up use following params:
Image Type: 16 Bit Unsigned.
Offset to first image: As in step 4 above.
rest of the parameters depends on the data.
hope that helps..
cheers,
- Divya Rathore
Research Engineer,
Deptt of Mathematics and Statistics,
IIT Kanpur,
INDIA.