> For the complete documentation index, see [llms.txt](https://docs.viesus.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.viesus.com/configuration/parameter-reference/local-parameters.md).

# Local Parameters

Local parameters control corrections applied to specific image regions.

VIESUS automatically calculates the appropriate correction for each image. The strength parameters scale how much of the calculated correction is actually applied.

<table><thead><tr><th width="200">Parameter</th><th width="95">Range</th><th width="95">Default</th><th>Description</th></tr></thead><tbody><tr><td><code>highlightfac</code></td><td>0.0 – 1.0</td><td>0.5</td><td><a href="/pages/PBvD9YH1VU9jKKYWr3Pn">Highlight region</a> correction factor</td></tr><tr><td><code>shadowfac</code></td><td>0.0 – 1.0</td><td>0.5</td><td><a href="/pages/PBvD9YH1VU9jKKYWr3Pn">Shadow region</a> correction factor</td></tr><tr><td><code>colorfac</code></td><td>0.0 – 1.0</td><td>0.5</td><td>Region-specific color correction factor</td></tr><tr><td><code>skinToneAdjFac</code></td><td>0.0 – 1.0</td><td>0.2</td><td>Saturation reduction in <a href="/pages/XgfZXDGQPgao20OFp9iu">face regions</a> (prevents "glowing" faces)</td></tr><tr><td><code>addflashfac</code></td><td>0.0 – 1.0</td><td>0.5</td><td><a href="/pages/6x3AsIljrmM8rTWn4UEl">Adaptive shadow highlighting</a> for faces (0.3 recommended)</td></tr></tbody></table>

## Color-specific adjustments

VIESUS applies dedicated adjustments to three color regions important for image quality: **skin**, **sky**, and **vegetation**. Each lives in its own sub-section (`Lpars.skin`, `Lpars.sky`, `Lpars.veg`) and uses the same parameter set:

<table><thead><tr><th width="200">Parameter</th><th width="118.2000732421875">Range</th><th width="95">Default</th><th>Description</th></tr></thead><tbody><tr><td><code>huerotation</code></td><td>-10.0 – 10.0</td><td>0.0</td><td><a href="/pages/ZTiMdZuJ6uJsG2Um9ga3">Hue rotation</a> for the specific color region</td></tr><tr><td><code>saturation</code></td><td>-1.0 – 1.0</td><td>0.0</td><td><a href="/pages/ZTiMdZuJ6uJsG2Um9ga3">Saturation adjustment</a> for the region</td></tr><tr><td><code>brightness</code></td><td>-1.0 – 1.0</td><td>0.0</td><td><a href="/pages/ZTiMdZuJ6uJsG2Um9ga3">Brightness adjustment</a> for the region</td></tr><tr><td><code>contrast</code></td><td>-1.0 – 1.0</td><td>0.0</td><td><a href="/pages/ZTiMdZuJ6uJsG2Um9ga3">Contrast adjustment</a> for the region</td></tr><tr><td><code>strength</code></td><td>0.0 – 1.0</td><td>1.0</td><td><a href="/pages/ZTiMdZuJ6uJsG2Um9ga3">Overall strength</a> of adjustments for the region</td></tr></tbody></table>


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