8.44. Fattal et al. 2002

8.44. Fattal et al. 2002
	8. The “Colors” Menu

8.44.1. Overview

Figure 16.230. “Fattal et al. 2002” tone mapping example

Original image

Filter applied with default settings, after changing image precision in GIMP to 32-bit floating point linear light.

This filter can be used to adapt an image, which may have a high dynamic range (HDR), for presentation using a low dynamic range. This operation reduces the magnitudes of local image gradients, producing luminance within the range 0.0-1.0.

This tonemapping approach was originally presented by Raanan Fattal, in the 2002 SIGGRAPH paper: Gradient Domain High Dynamic Range Compression.

	Note
	This filter is slow on larger images. For finding the best settings for your image you could make a small relevant selection first and save that as a preset before using that for the whole image.

8.44.2. Activating the filter

This filter is found in the image window menu under Colors → Tone Mapping → Fattal et al. 2002.

8.44.3. Options

Figure 16.231. The “Fattal et al. 2002” filter Dialog

Presets: “Presets” are a common feature for several Colors commands. You can find its description in Section 8.1.1, “Colors Common Features”.
Alpha: Gradient threshold for detail enhancement.
Beta: Strength of local detail enhancement.
Saturation: Global color saturation factor.
Noise: Gradient threshold for lowering detail enhancement.
Input Type, Clipping, Blending Options, Preview and Split view: These are common features described in Section 8.1.1, “Colors Common Features”.