> 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/background-and-cropping.md).

# Background & Cropping

The Background section (replacement, color substitution, balance) and the AutoCrop section (portrait auto-cropping).

## Background Handling (`Background`)

Background replacement, color substitution, and balance.

<table><thead><tr><th width="125.5999755859375">Parameter</th><th width="91.800048828125">Value</th><th width="95.7999267578125">Default</th><th>Description</th></tr></thead><tbody><tr><td><code>ReplacePath</code></td><td>String</td><td>—</td><td>Path to a <a href="/features/features/background-handling.md">replacement background image</a></td></tr><tr><td><code>backgroundR</code></td><td>0 – 255</td><td>255</td><td><a href="/features/features/background-handling.md">Red component</a> for background color replacement</td></tr><tr><td><code>backgroundG</code></td><td>0 – 255</td><td>255</td><td><a href="/features/features/background-handling.md">Green component</a> for background color replacement</td></tr><tr><td><code>backgroundB</code></td><td>0 – 255</td><td>255</td><td><a href="/features/features/background-handling.md">Blue component</a> for background color replacement</td></tr><tr><td><code>balanceH</code></td><td>-1.0 – 1.0</td><td>0.0</td><td><a href="/features/features/background-handling.md">Hue balance</a> adjustment for background</td></tr><tr><td><code>balanceS</code></td><td>-1.0 – 1.0</td><td>0.0</td><td><a href="/features/features/background-handling.md">Saturation balance</a> adjustment for background</td></tr><tr><td><code>balanceV</code></td><td>-1.0 – 1.0</td><td>0.0</td><td><a href="/features/features/background-handling.md">Value balance</a> adjustment for background</td></tr></tbody></table>

***

## Portrait Auto-Cropping (`AutoCrop`)

Automatic cropping based on facial detection. See [Key Features → Adaptive Auto-Cropping](/discover/key-features.md#adaptive-auto-cropping).

<table><thead><tr><th width="219.2000732421875">Parameter</th><th width="82.2000732421875">Value</th><th width="95">Default</th><th>Description</th></tr></thead><tbody><tr><td><code>HeadYawCoeff</code></td><td>Float</td><td>0.67</td><td>Coefficient for head yaw adjustment</td></tr><tr><td><code>HeadPitchCoeff</code></td><td>Float</td><td>0.75</td><td>Coefficient for head pitch adjustment</td></tr><tr><td><code>HeadroomFixed</code></td><td>0, 1</td><td>1</td><td>Use fixed headroom calculation</td></tr><tr><td><code>HeadroomUnit</code></td><td>Integer</td><td>0</td><td>Headroom unit type</td></tr><tr><td><code>ImageToHeadRatio</code></td><td>Float</td><td>0.48</td><td>Ratio of image to head size</td></tr><tr><td><code>HeadroomLeft</code></td><td>Float</td><td>0.1</td><td><a href="/features/features/portrait-auto-cropping.md">Left side headroom</a></td></tr><tr><td><code>Headroom</code></td><td>Float</td><td>0.1</td><td><a href="/features/features/portrait-auto-cropping.md">General headroom</a></td></tr><tr><td><code>CropModeHeadroom</code></td><td>Float</td><td>0.0</td><td><a href="/features/features/portrait-auto-cropping.md">Headroom for crop mode</a></td></tr><tr><td><code>AspectHeight</code></td><td>Float</td><td>1.0</td><td>Target <a href="/features/features/portrait-auto-cropping.md">aspect ratio height</a></td></tr><tr><td><code>AspectWidth</code></td><td>Float</td><td>1.0</td><td>Target <a href="/features/features/portrait-auto-cropping.md">aspect ratio width</a></td></tr><tr><td><code>PortraitMode</code></td><td>Integer</td><td>2</td><td><a href="/features/features/portrait-auto-cropping.md">Portrait cropping mode</a></td></tr><tr><td><code>AdaptAspectRatioToFace</code></td><td>0, 1</td><td>1</td><td>Adapt aspect ratio based on face detection</td></tr><tr><td><code>AspectRatio</code></td><td>Integer</td><td>0</td><td>Fixed aspect ratio mode</td></tr><tr><td><code>CropMode</code></td><td>0 – 2</td><td>0</td><td><a href="/features/features/portrait-auto-cropping.md">Cropping mode</a> (see <a href="#cropmode-values">CropMode values</a> below)</td></tr></tbody></table>

### `CropMode` values

<table><thead><tr><th width="118">Value</th><th>Description</th></tr></thead><tbody><tr><td><code>0</code></td><td>Manual — uses the configured aspect ratio and headroom values without face-based adjustment</td></tr><tr><td><code>1</code></td><td>Automatic — crops to the dominant detected face using the configured aspect ratio and headroom</td></tr><tr><td><code>2</code></td><td>Group — crops to include all detected faces (for group portraits)</td></tr></tbody></table>


---

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