> 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

The Gpars section — global enhancement strengths, specialised AI strengths, and manual corrections applied to the whole image.

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="/features/features/base-enhancement.md">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="/features/features/global-color-correction.md">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="/features/features/sharpening.md">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="/features/features/noise-reduction.md">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="/features/features/noise-reduction.md">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="/features/features/grain-addition.md">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="/features/features/red-eye-removal.md">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="/features/features/face-detection.md">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="/features/features/red-eye-removal.md">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="/features/features/face-reconstruction.md">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="/features/features/background-blur.md">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="/features/features/face-reconstruction.md">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="/features/features/ai-artifact-removal.md">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="/features/hdr-support.md">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="/features/scene-based-enhancement.md">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="/features/features/global-color-correction.md">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="/features/features/global-color-correction.md">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="/features/features/global-color-correction.md">saturation adjustment</a></td></tr><tr><td><code>r</code></td><td>-1.0 – 1.0</td><td>0.0</td><td><a href="/features/features/global-color-correction.md">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="/features/features/global-color-correction.md">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="/features/features/global-color-correction.md">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="/features/features/sharpening.md">Global sharpening</a> strength</td></tr></tbody></table>


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