> 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/global-parameters.md).

# Global Parameters

Global parameters control enhancement algorithms applied to the entire image.

## Enhancement strength

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>brstrength</code></td><td>0.0 – 1.0</td><td>0.5</td><td><a href="/pages/JvqjGnjGdqsk3kQASBze">Brightness correction</a> (most visible on underexposed images)</td></tr><tr><td><code>ccstrength</code></td><td>0.0 – 1.0</td><td>0.5</td><td><a href="/pages/g1xL8FdKDIGU1p5swvLM">Color correction</a> (removes color casts)</td></tr><tr><td><code>shplocalstrength</code></td><td>0.0 – 1.0</td><td>0.5</td><td><a href="/pages/Q5YiJE6x8rqvzavC5OKq">Local sharpening</a> strength (visible in foliage, less in sky regions)</td></tr><tr><td><code>nrmonostrength</code></td><td>0.0 – 1.0</td><td>0.5</td><td><a href="/pages/14aIw2hrFF71b869yDL0">Noise reduction</a> strength for monochrome images</td></tr><tr><td><code>nrstrength</code></td><td>0.0 – 1.0</td><td>0.5</td><td><a href="/pages/14aIw2hrFF71b869yDL0">Noise reduction</a> strength for color images</td></tr><tr><td><code>gastrength</code></td><td>0.0 – 1.0</td><td>0.5</td><td><a href="/pages/4vJbdyKDZNCa8fDdJ0Tk">Grain addition</a> strength (reduces banding/posterisation)</td></tr></tbody></table>

## Specialised enhancement

<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>rerstrength</code></td><td>0.0 – 1.0</td><td>1.0</td><td><a href="/pages/Nt5fpiiAJhxOKjLnl6zV">Red-eye reduction</a> (higher values increase detection — and false positives)</td></tr><tr><td><code>fdstrength</code></td><td>0.0 – 1.0</td><td>0.5</td><td><a href="/pages/zL6tVzIb4U18r0oQBZ2D">Face detection</a> sensitivity. Higher values detect smaller faces at the cost of processing time. Useful for group shots.</td></tr><tr><td><code>eyestrength</code></td><td>0.0 – 1.0</td><td>0.5</td><td><a href="/pages/Nt5fpiiAJhxOKjLnl6zV">Eye detection</a> strictness for red-eye correction</td></tr><tr><td><code>frstrength</code></td><td>0.0 – 1.0</td><td>0.3</td><td><a href="/pages/lIiR838RscSsqGYHEDdn">Face reconstruction</a> strength for smaller faces</td></tr><tr><td><code>blurstrength</code></td><td>0.0 – 1.0</td><td>0.0</td><td><a href="/pages/YihtRB8SqqViYxKr2hDM">Background blur</a> / computational bokeh strength</td></tr><tr><td><code>srstrength</code></td><td>0.0 – 1.0</td><td>0.9</td><td>Super-resolution blending strength with default upscaling</td></tr><tr><td><code>sfstrength</code></td><td>0.0 – 1.0</td><td>0.25</td><td><a href="/pages/lIiR838RscSsqGYHEDdn">Small-face reconstruction</a> importance (0.25 – 0.50 recommended)</td></tr><tr><td><code>dastrength</code></td><td>0.0 – 1.0</td><td>0.5</td><td>Dark scene / night shot brightness correction</td></tr><tr><td><code>arstrength</code></td><td>0.0 – 1.0</td><td>0.5</td><td><a href="/pages/Ns1fAktWQXSySxYvkfKM">AI Artifact Removal</a> activation threshold. Higher = only triggers on more severely degraded images</td></tr><tr><td><code>hdrstrength</code></td><td>0.0 – 1.0</td><td>0.5</td><td><a href="/pages/JHPIX3efhL8sQDBhsChH">HDR tonemapping</a> strength</td></tr><tr><td><code>vscenestrength</code></td><td>0.0 – 1.0</td><td>1.0</td><td>Blends the <a href="/pages/nGGFNJ96jlemzu6AVo7b">detected scene</a>'s parameters with the defaults. <strong>0.0</strong> = full default behavior; <strong>1.0</strong> = full vScene parameters applied</td></tr></tbody></table>

## Manual corrections

{% hint style="warning" %}
Manual corrections are static and applied **at the end** of automatic processing, regardless of the analysis result. Adjust carefully — they can override otherwise correct automatic behavior.
{% endhint %}

<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>brightness</code></td><td>-1.0 – 1.0</td><td>0.0</td><td>Global <a href="/pages/g1xL8FdKDIGU1p5swvLM">brightness adjustment</a></td></tr><tr><td><code>contrast</code></td><td>-1.0 – 1.0</td><td>0.0</td><td>Global <a href="/pages/g1xL8FdKDIGU1p5swvLM">contrast adjustment</a></td></tr><tr><td><code>saturation</code></td><td>-1.0 – 1.0</td><td>0.0</td><td>Global <a href="/pages/g1xL8FdKDIGU1p5swvLM">saturation adjustment</a></td></tr><tr><td><code>r</code></td><td>-1.0 – 1.0</td><td>0.0</td><td><a href="/pages/g1xL8FdKDIGU1p5swvLM">Red channel</a> color balance</td></tr><tr><td><code>g</code></td><td>-1.0 – 1.0</td><td>0.0</td><td><a href="/pages/g1xL8FdKDIGU1p5swvLM">Green channel</a> color balance</td></tr><tr><td><code>b</code></td><td>-1.0 – 1.0</td><td>0.0</td><td><a href="/pages/g1xL8FdKDIGU1p5swvLM">Blue channel</a> color balance</td></tr><tr><td><code>shpglobalstrength</code></td><td>0.0 – 1.0</td><td>0.0</td><td><a href="/pages/Q5YiJE6x8rqvzavC5OKq">Global sharpening</a> strength</td></tr></tbody></table>


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