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I want to input some 8 bit images. How?

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Q15. I want to input some 8 bit images. How?
to3d will recognize 8 bit grayscale images stored in the raw PGM format, and assemble them into a byte-value AFNI dataset, or convert them into a short-valued dataset (using the -datum command line option). You can use the netpbm utilities (available at the AFNI distribution sites), or the program xv (available here) to convert images of many different types (e.g., TIFF) to the PGM format. This makes it possible to assemble 3D (or 3D+time) grayscale datasets from modalities other than MRI (e.g., digitized photographs).

The AFNI program mritopgm will read a single 2D image in one of the formats described above and convert it to to the raw PGM format. This can be useful for incorporating 16 bit MR images into other documents that require 8 bit files; for example

  mritopgm im.1.08 | pnmtotiff > im.tif
will produce a TIFF image from a 2D MRI slice.

There is no provision at present for colored 3D datasets in the AFNI package.

This FAQ applies to: Any version.

Created by Robert Cox
Last modified 2005-07-31 10:30

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