> 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/features/features/red-eye-removal.md).

# Red-Eye Removal

Detects and removes red-eyes caused by flash photography.

{% hint style="info" %}
**Requires:** [Face Detection](/features/features/face-detection.md) — enabled automatically when this feature is active.
{% endhint %}

## Example

{% columns %}
{% column %}
**Before**

<figure><img src="https://919968377-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FG3eQlcnlDKtn9yl3mxsx%2Fuploads%2Fgit-blob-2aac38d3a6989f640b75c2aeecf11934ec13a3c3%2Fplaceholder.svg?alt=media" alt="Before — Red-Eye Removal"><figcaption></figcaption></figure>
{% endcolumn %}

{% column %}
**After**

<figure><img src="https://919968377-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FG3eQlcnlDKtn9yl3mxsx%2Fuploads%2Fgit-blob-2aac38d3a6989f640b75c2aeecf11934ec13a3c3%2Fplaceholder.svg?alt=media" alt="After — Red-Eye Removal"><figcaption></figcaption></figure>
{% endcolumn %}
{% endcolumns %}

## Parameters

<table><thead><tr><th width="131.199951171875">Parameter</th><th width="100">Section</th><th width="95">Value</th><th width="95">Default</th><th>Description</th></tr></thead><tbody><tr><td><code>RERmode</code></td><td><code>Config</code></td><td>0 – 2</td><td>0</td><td>Mode selection (see below)</td></tr><tr><td><code>rerstrength</code></td><td><code>Gpars</code></td><td>0.0 – 1.0</td><td>1.0</td><td>Detection strictness — higher values increase detection (and false positives)</td></tr><tr><td><code>eyestrength</code></td><td><code>Gpars</code></td><td>0.0 – 1.0</td><td>0.5</td><td>Eye detection strictness</td></tr></tbody></table>

## Modes

<table><thead><tr><th width="138.7999267578125">Value</th><th>Description</th></tr></thead><tbody><tr><td><strong>0</strong> — Off</td><td>No red-eye removal</td></tr><tr><td><strong>1</strong> — Safe</td><td>Standard detection — minimises false positives</td></tr><tr><td><strong>2</strong> — Extended</td><td>More aggressive detection — catches more red-eye but more false positives</td></tr></tbody></table>

{% hint style="success" %}
**Recommended:** Use Mode 1 (Safe) for flash photography — it minimises false positives. Switch to Mode 2 only if red-eye is being missed.
{% endhint %}


---

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