Drago Adaptive Log Mapping

Implement Drago's adaptive logarithmic tone mapping, a technique used in tone mapping to preserve details in high dynamic range images. This method extends traditional logarithmic tone mapping by adapting the base of the logarithm based on local luminance.

The goal is to map high dynamic range images to lower dynamic ranges while preserving details, which is crucial in computational photography. The logarithmic tone mapping approach is based on the idea that human perception of light is logarithmic, and can be represented by the equation $L_d = \frac{\log_{b}(1 + L)}{\log_{b}(1 + L_{max})}$, where $L$ is the luminance and $b$ is the adaptive base.

Here are the key steps:

1. Compute the luminance $L$ from the input image.
2. Determine the maximum luminance $L_{max}$.
3. Calculate the adaptive base $b$ based on local luminance.
4. Apply the logarithmic tone mapping using the calculated $b$.

This technique is widely used in high dynamic range imaging applications.