ImageDev

BlendAlphaChannelWithValue

Blends an RGBA input image with a padding color into an RGB output image.

Access to parameter description

For an introduction to color image filters: section Color Transforms.

BlendAlphaChannelWithValue combines an image with a background, defined by a single color, taking into account the alpha channel. Considering all $\alpha$ values between 0 and 1, the resulting intensity of each color component is computed with the following formula:
$O=I_i*\alpha + I_p*\left (1-\alpha \right )$ where

See also

Function Syntax

This function returns outputRgbImage. 
// Function prototype
std::shared_ptr< iolink::ImageView >
blendAlphaChannelWithValue( std::shared_ptr< iolink::ImageView > inputRgbaImage,
                            const iolink::Vector3i32& paddingColor,
                            std::shared_ptr< iolink::ImageView > outputRgbImage = nullptr );
This function returns outputRgbImage. 
// Function prototype.
blend_alpha_channel_with_value(input_rgba_image: idt.ImageType,
                               padding_color: Iterable[int] = [0, 0, 0],
                               output_rgb_image: idt.ImageType = None) -> idt.ImageType
This function returns outputRgbImage. 
// Function prototype.
public static IOLink.ImageView
BlendAlphaChannelWithValue( IOLink.ImageView inputRgbaImage,
                            int[] paddingColor = null,
                            IOLink.ImageView outputRgbImage = null );

Class Syntax

Parameters

Parameter Name Description Type Supported Values Default Value
input
inputRgbaImage
The RGBA input image. Image Multispectral nullptr
input
paddingColor
The padding color. Vector3i32 Any value {0, 0, 0}
output
outputRgbImage
The RGB output image. Its spatial dimensions and type are forced to the same values as the inputs. Image nullptr
Parameter Name Description Type Supported Values Default Value
input
input_rgba_image
The RGBA input image. image Multispectral None
input
padding_color
The padding color. vector3i32 Any value [0, 0, 0]
output
output_rgb_image
The RGB output image. Its spatial dimensions and type are forced to the same values as the inputs. image None
Parameter Name Description Type Supported Values Default Value
input
inputRgbaImage
The RGBA input image. Image Multispectral null
input
paddingColor
The padding color. Vector3i32 Any value {0, 0, 0}
output
outputRgbImage
The RGB output image. Its spatial dimensions and type are forced to the same values as the inputs. Image null

Object Examples

auto icon = ioformat::readImage( std::string( IMAGEDEVDATA_IMAGES_FOLDER ) + "icon.png" );

BlendAlphaChannelWithValue blendAlphaChannelWithValueAlgo;
blendAlphaChannelWithValueAlgo.setInputRgbaImage( icon );
blendAlphaChannelWithValueAlgo.setPaddingColor( {255, 255, 255} );
blendAlphaChannelWithValueAlgo.execute();

std::cout << "outputRgbImage:" << blendAlphaChannelWithValueAlgo.outputRgbImage()->toString();

icon = ioformat.read_image(imagedev_data.get_image_path("icon.png"))

blend_alpha_channel_with_value_algo = imagedev.BlendAlphaChannelWithValue()
blend_alpha_channel_with_value_algo.input_rgba_image = icon
blend_alpha_channel_with_value_algo.padding_color = [255, 255, 255]
blend_alpha_channel_with_value_algo.execute()

print("output_rgb_image:", str(blend_alpha_channel_with_value_algo.output_rgb_image))

ImageView icon = ViewIO.ReadImage( @"Data/images/icon.png" );

BlendAlphaChannelWithValue blendAlphaChannelWithValueAlgo = new BlendAlphaChannelWithValue
{
    inputRgbaImage = icon,
    paddingColor = new int[]{255, 255, 255}
};
blendAlphaChannelWithValueAlgo.Execute();

Console.WriteLine( "outputRgbImage:" + blendAlphaChannelWithValueAlgo.outputRgbImage.ToString() );

Function Examples

auto icon = ioformat::readImage( std::string( IMAGEDEVDATA_IMAGES_FOLDER ) + "icon.png" );

auto result = blendAlphaChannelWithValue( icon, {255, 255, 255} );

std::cout << "outputRgbImage:" << result->toString();

icon = ioformat.read_image(imagedev_data.get_image_path("icon.png"))

result = imagedev.blend_alpha_channel_with_value(icon, [255, 255, 255])

print("output_rgb_image:", str(result))

ImageView icon = ViewIO.ReadImage( @"Data/images/icon.png" );

IOLink.ImageView result = Processing.BlendAlphaChannelWithValue( icon, new int[]{255, 255, 255} );

Console.WriteLine( "outputRgbImage:" + result.ToString() );





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