Original tone mapped image by iCAM06 {p=134, ct=0.65}:

Histogram of the tone mapped image:

Image statistics of the tone-mapped image:

Median percentile of the lightness (CIE L*a*b*): 43.6285
Mean of the chroma value (CIE L*a*b*): 36.9336
Image produced by the generic tone mapping operator:
(evalution of the fit via PSNR: PSNR = 29.7764dB)

Fitted tone curve of the generic tone mapping operator,
compared to the luminance compression done by the tone mapping operator:

Fitted parameters of the generic tmo:

Exposure: 2.2969
Contrast: 0.63698
Low midtone range: 2.7139
High midtone range: 0.90366
Saturation: 0.61309
Frequencies: 1.588, 1.241, 1.22, 1.225, 1.196