Unit used in Straight Line

[Maristela Sayuri Inoue]

　　I'm using Image J software on MR　image to calculate the distance between some structures. I would like to ask, which unit of lengths Image J use to straight line. I didn't enter that distance in the Analyze/Set Scale dialog box, I only
calculated many, and many images and now I don't know what kind of unit (mm, cm, pixel size) the software uses in this case.
    One more problem is because the original size was 128x128 pixels and I resized to 512x512 pixels to calculate the distance using the straight line on tool bar.
    I will appreciate very much your help and also your suggestion.
            Best Regards,
                 Maristela

[Wayne Rasband]

> 　　I'm using Image J software on MR　image to calculate the distance
> between some structures. I would like to ask, which unit of lengths
> Image J use to straight line. I didn't enter that distance in the
> Analyze/Set Scale dialog box, I only
> calculated many, and many images and now I don't know what kind of
> unit (mm, cm, pixel size) the software uses in this case.

The information displayed above every image includes the unit. For
example, this text

      300x300 mm (512x512); 16-bit; 512K

is displayed above one of the CT images in my DICOM collection. The
width of this image is 300 mm (or 512 pixels), the height is 300 mm (or
512 pixels), it uses 16-bits (2 bytes) per pixel, and 512K bytes of
memory.

This text

     2184x1472 pixels; RGB; 12MB

is displayed above the new "M51 Galaxy (116K, RGB)" image added to the
File>Open Samples menu in ImageJ 1.35m. The width is 2184 pixels, the
height is 1472 pixels, it is in RGB format (4 bytes per pixel), and it
uses 12 megabytes of memory (a compression ratio of 116:1).

-wayne