How are the channel_mult for different resolutions determined

[SvenGroen]

Hi, in script_util.py when you create the model/classifier (line 148, 238 & 353) you support the image sizes of 512, 256, 128 and 64 by specifying the channel_mult.

How have you determined the channel_mult numbers for the different image sizes? have you figured them out by experimenting, or is there some underlying logic?

If I would like to try out a resolution of 32x32 or 16x16, how would I have to define the channel_mult?

Cheers, Sven