Tckmap stuck when computing super resolution color coded TDI

Dear Mrtrix communnity,

I tried to run tckmap to generate a super resolved color coded TDI map from a whole-brain track file with 6 million streamlines. I chose an isotropic voxel size of 0.225 mm.

However after writing the resulting TDI file to disk, the process gets stuck and does not finish. Could this be an insuficient RAM issue?

I have a Windows 10 machine with 12 GB RAM and the latest version of MRtrix run from MSYS2.

Thank you very much.

Best regards


Most likely. At this resolution, and assuming this is standard adult human whole-brain data, you’ll be talking about a matrix size of around 1,000 voxels across, which means about a billion voxels in total, each requiring 3×32-bit floats (12 bytes). So you’ll looking at an output file size in the region of 12GB, which won’t all fit in your system’s RAM. That means the system will most likely rely on the virtual memory subsystem (page file on Windows) to swap memory pages from RAM to disk and vice-versa. At this point, the system typically grinds to a halt…

It’s just too big an image, I think. You’ll probably also find you can’t display it unless you have a very high-end graphics card capable of rendering such massive images…

Ok, thank you very much for the reply. I tried half the original resolution and it worked this time

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