This command implements two tone mapping operators: contrast
mapping and contrast equalization. Both operators can produce
very sharp images (sometimes non-photorealistic) while minimizing
contrast reversal (halo artifacts). More information on these
operators can be found in:
Rafal Mantiuk, Karol Myszkowski, Hans-Peter Seidel.
A Perceptual Framework for Contrast Processing of High Dynamic Range Images
In: ACM Transactions on Applied Perception 3 (3), pp. 286-308, 2006.
This version contains several performance improvements made by Ed Brambley.
If you find this TMO useful in your research project, please cite the
The result of this TMO requires gamma correction.
--equalize-contrast <val>, -e <val>
Use the contrast equalization algorithm. If this option is not
specified, the contrast mapping algorithm will be used. The
contrast equalization algorithm requires scaling parameter that
controls the amount sharpenning, which can range from 0.1 (very sharp)
to 1 (less sharp).
contrast equalization results in very sharp, but also less
natural images. contrast equalization may also enhance noise in
--factor <val>, -f <val>
Contrast scaling factor (values 0-1) determines how much contrast
magnitudes should be reduced. This option cannot be used with
equalize-contrast. The lower value results in a sharper
image. Default value: 0.3
--saturation <val>, -s <val>
Saturation correction (values 0-1). The lower value results in
stronger desaturation. Default value: 0.8
Print additional information during program execution.
For optimal results you can output the result to pfsview and manually
adjust the dynamic range window. Then save the image in pfsview by
selecting 'Save image...' from the 'Frame' menu or pressing 's'.