toasty transform fx3-to-rgb

The transform fx3-to-rgb command transform a pyramid in an “Fx3” format — three planes of floating-point data — and converts them to RGB(A) image files.


toasty transform fx3-to-rgb
   [--parallelism FACTOR]
   [--start DEPTH]
   [--clip NUMBER]

See the Standard image-loading options section for documentation on those options.

The PYRAMID-DIR argument gives the name of a tile pyramid. It should contain Numpy data files in one of the supported Toasty “Fx3” formats. One potential source of such data is tiling an OpenEXR file.

The --clip NUMBER argument specifies the point at which the floating-point values will be clipped. By default, the input floating-point data are expected to range between 0 and 1, which will be mapped to the range 0–255 in the standard 8-bit RGB color scheme. If, for example, you specify --clip=0.1, then floating-point values of 0.1 will be mapped to 255 (i.e. full brightness). Values greater than this cutoff will be clipped and appear equally bright in the output RGB images.

The --parallelism FACTOR argument specifies the level of parallism to use. On operating systems that support parallel processing, the default is to use all CPUs. To disable parallel processing, explicitly specify a factor of 1.


After the clip is applied, the floating-point data have a square-root transform applied before being mapped to RGB values. This could/should be made configurable, but this hasn’t yet been done.