June 3, 2004

Lab Contents

Differences between NIH Image on the Mac and Scion Image on the PC

Differences between Scion Image 1.61 and NIH Image 1.61 as of 10/02 are shown in magenta.  The current version (5/04) of NIH Image is 1.62, and of Scion Image is 1.63 for Mac and Beta 4.02 for Windows 95 to XP. Some differences are due to differences in the operating systems of the Mac and PC. Other differences are due to bugs or intensional implementation differences in Scion Image.

Differences between NIH (Scion) Image and ImageJ are shown in green.The current version (6/04) of ImageJ is 1.33a.

 


Loading Images

On both computers, images are loaded using the File -> Open..., or File -> Import... commands.

NIH Image, Scion Image

Mac

PC

  File types

 .tiff, .pict

.tiff, .bmp

(Windows uses three letter extensions.  Photoshop in Windows recognizes .tif.  Scion Image doesn't care, so here we use .tif .)

 Drag and Drop

 May not work unless Image is already running.  Will not work on my PC (running NT and 1.61- get an 'error getting handle to NT driver).
ImageJ reads  TIFF, GIF, JPEG, BMP, DICOM, FITS and "raw".  For TIFF files at least, ImageJ will recognize tif and tiff extensions, and read tiff files with no extension.

TIFF files are common to both platforms, so we will use .tiff files almost exclusively. (The byte order in the TIFF header is different, but the TIFF 6.0 specification requires that applications read either, and NIH Image and Scion Image both conform.


Convolution Kernels

The Process / Convolve... menu uses small arrays of numbers known as Kernels, which are stored as text files. AS THEY ARE DOWNLOADED, the Mac kernel files are not recognized by the PC and the PC files can cause the Mac to hang. The kernel files have the same names on each type of computer, but are in different locations.

 Mac

 PC

 Sample Images / Kernels  ... / Scion Image / Kernels

There is a kernels folder in the Sample Images folder for this course, that has the Mac text files with a '.txt' subscript added to the file names. These work both on the Mac and PC.