# Virtual Background (/en/realtime-media/video/build/apply-video-effects/virtual-background/unreal)

> For AI agents: see the complete documentation index at [llms.txt](/llms.txt).

Virtual Background enables users to blur their background, or replace it with a solid color or an image. This feature is applicable to use-cases such as online conferences, online classes, and live streaming. It helps protect personal privacy and reduces audience distraction.

      
  
      
  
      
  
      
  
      
  
      
  
      
  
      
  
      
  
      
  
      
    ## Understand the tech [#understand-the-tech-10]

    Virtual Background offers the following options:

    | Feature                                 | Example                                                                                                                                                                                                                                                                                                               |
    | --------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
    | Blurred background and image background | ![image](https://assets-docs.agora.io/images/extensions-marketplace/blurred-background.jpg)                                                                                                                                                                                                                           |
    | Video/Animated background               | <video src="https://assets-docs.agora.io/images/extensions-marketplace/virtual-background.mp4" poster="https://web-cdn.agora.io/docs-files/1654571689670" width="100%" height="auto">Your browser does not support the `video` element.</video>                                                                       |
    | Portrait-in-picture                     | ![portrait-in-picture](https://assets-docs.agora.io/images/extensions-marketplace/portrait-in-picture.jpg) Allows the presenter to use slides as the virtual background while superimposing their video. The effect is similar to a weather news cast on television, preventing interruptions during a layout toggle. |

    Want to test Virtual Background? Try the <a href="https://webdemo.agora.io/virtualBackground/index.html">online demo</a>.

    ## Prerequisites [#prerequisites-10]

    Ensure that you have implemented the [SDK quickstart](/en/realtime-media/video/get-started-sdk) in your project.

    ## Implement virtual background [#implement-virtual-background-10]

    This section shows you how to add a virtual background to the local video.

    ### Set a blurred background [#set-a-blurred-background-9]

    To blur the video background, use the following code:

    ```cpp
    void UMyUserWidget::SetBackgroundBlur(VirtualBackgroundSource& virtualBackgroundSource)
    {
        VirtualBackgroundSource virtualBackgroundSource;
        SegmentationProperty segmentationProperty;

        // Set background blur
        virtualBackgroundSource.background_source_type = VirtualBackgroundSource::BACKGROUND_BLUR;
        virtualBackgroundSource.blur_degree = VirtualBackgroundSource::BACKGROUND_BLUR_DEGREE::BLUR_DEGREE_HIGH;

        // Set processing properties for background
        segmentationProperty.modelType = SegmentationProperty::SEG_MODEL_AI;
        segmentationProperty.greenCapacity = 0.5F;

        // Enable virtual background
        agoraEngine->enableVirtualBackground(true, virtualBackgroundSource, segmentationProperty);
        UE_LOG(LogTemp, Log, TEXT("Blur background enabled"));
    }
    ```

    ### Set a color background [#set-a-color-background-9]

    To apply a solid color as the virtual background, use a hexadecimal color code. For example, `0x0000FF` for blue:

    ```cpp
    void UMyUserWidget::SetBackgroundColor(VirtualBackgroundSource& virtualBackgroundSource)
    {
        VirtualBackgroundSource virtualBackgroundSource;
        SegmentationProperty segmentationProperty;

        // Set a solid background color
        virtualBackgroundSource.background_source_type = VirtualBackgroundSource::BACKGROUND_COLOR;
        virtualBackgroundSource.color = 0x0000FF;

        // Set processing properties for background
        segmentationProperty.modelType = SegmentationProperty::SEG_MODEL_AI;
        segmentationProperty.greenCapacity = 0.5F;

        // Enable virtual background
        agoraEngine->enableVirtualBackground(true, virtualBackgroundSource, segmentationProperty);
        UE_LOG(LogTemp, Log, TEXT("Color background enabled"));
    }
    ```

    ### Set an image background [#set-an-image-background-9]

    To set a custom image as the virtual background, specify the absolute path to the image file.

    ```cpp
    void UMyUserWidget::SetBackgroundImage(VirtualBackgroundSource& virtualBackgroundSource)
    {
        VirtualBackgroundSource virtualBackgroundSource;
        SegmentationProperty segmentationProperty;

        // Set a background image
        virtualBackgroundSource.background_source_type = VirtualBackgroundSource::BACKGROUND_IMG;
        virtualBackgroundSource.source = "<absolute path to an image file>";

        // Set processing properties for background
        segmentationProperty.modelType = SegmentationProperty::SEG_MODEL_AI;
        segmentationProperty.greenCapacity = 0.5F;

        // Enable virtual background
        agoraEngine->enableVirtualBackground(true, virtualBackgroundSource, segmentationProperty);
        UE_LOG(LogTemp, Log, TEXT("Image background enabled"));
    }
    ```

    ### Reset the background [#reset-the-background-8]

    To disable the virtual background and revert to the original video state, use the following code:

    ```cpp
    void UMyUserWidget::ResetVirtualBackground()
    {
        VirtualBackgroundSource virtualBackgroundSource;
        SegmentationProperty segmentationProperty;

        // Reset the background state
        virtualBackgroundSource.background_source_type = VirtualBackgroundSource::BACKGROUND_COLOR;
        virtualBackgroundSource.color = 0xFFFFFF;

        // Set processing properties for background
        segmentationProperty.modelType = SegmentationProperty::SEG_MODEL_AI;
        segmentationProperty.greenCapacity = 0.5F;

        // Disable virtual background
        agoraEngine->enableVirtualBackground(false, virtualBackgroundSource, segmentationProperty);
    }
    ```

    ## Reference [#reference-10]

    This section contains content that completes the information in this page, or points you to documentation that explains other aspects of this product.

    ### API reference [#api-reference-9]

    * [`enableVirtualBackground`](https://api-ref.agora.io/en/video-sdk/unreal/4.x/API/class_irtcengine.html#api_irtcengine_enablevirtualbackground)
    * [`VirtualBackgroundSource`](https://api-ref.agora.io/en/video-sdk/unreal/4.x/API/class_virtualbackgroundsource.html)
    * [`SegmentationProperty`](https://api-ref.agora.io/en/video-sdk/unreal/4.x/API/class_segmentationproperty.html)