Hi,

I’m not an expert but since your question hasn’t been answered yet I thought I’d share how I’d do that.

But as I’m not an expert this might be a wrong way. Please verify the following first.

For example to go from [0, 110] to [-1, 1] you’d need a conversion like

target_intensity = (2/110) * source_intensity - 1

I think that can be done by the following procedure.

1. You multiply every voxel (not just WM) of the original mri by 2/110 using mri_concat --mul (MailScanner has detected a possible fraud attempt from "secure-web.cisco.com" claiming to be https://surfer.nmr.mgh.harvard.edu/fswiki/mri_concat)

2. You add -1 to the result of 1 using mri_concat --add

3. You prepare a mask image (=M) of the white matter using mri_binarize (MailScanner has detected a possible fraud attempt from "secure-web.cisco.com" claiming to be https://surfer.nmr.mgh.harvard.edu/fswiki/mri_binarize).

4. You mask the result of 2 with M as the mask using mri_mask (MailScanner has detected a possible fraud attempt from "secure-web.cisco.com" claiming to be https://surfer.nmr.mgh.harvard.edu/fswiki/mri_mask)

Hope this helps.

Best,

Horsng Junn

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2020. 12. 11. 오전 4:15, Hye Min Shin <shinhm91@bu.edu> 작성:

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Hello,

I was wondering if there was a way to scale intensities of normalized T1 images. For instance, I wanted to rescale intensities of white matter from [0,110] to [-1, 1] and intensities gray matter from [0, 80] to [-1, 1].

I wanted to rescale intensities to get consistent normalization levels across all T1 images for neural networks.

Best,
Julia Shin
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