This component is obsolete and its use in filters is not recommended. Use the recent version of the component.
The Blend 1.005 component blends together layers (colors or images) provided by the Foreground and Background inputs, taking into account their alpha channels, the Opacity value and the specified blending mode. This is a map component.
Foreground: Map Input
Provides the foreground layer which is 'placed' over the background layer.
Background: Map Input
Provides the background layer which is 'placed' underneath the foreground layer.
Opacity: Map Input
Defines the opacity of the foreground layer. The value of 0 makes the foreground layer completely invisible. The value of 100 makes the foreground layer fully visible. The actual visibility and look of the foreground layer in the output image are also affected by the selected Mode and the alpha channel of the foreground layer.
Since Opacity is a map input, its value can be controlled separately for different image areas by connecting a map component. In this case, its output image serves as a mask, where the brightness level defines the opacity: black areas correspond to Opacity of 0, white areas to Opacity of 100, and the opacity values in-between are represented by intermediate brightness levels.
Defines the way the foreground layer is combined with the background layer. The descriptions of the blending modes below assume that Opacity is set to 100 and the alpha channel values for both layers are set to 255 (no transparency):
Normal
This is the default mode. The background layer is completely covered with the foreground layer.
Darken
Compares the values of R, G and B channels for both the foreground and background layers and selects the smaller value for each channel. The three selected values are combined into a color to produce the result.
Multiply
Multiplies the values of R, G and B channels for both the foreground and background layers. The channel values are considered to be in the range of 0 to 1, so the result is darker than both original images. Multiplying any source with black color always produces black, and multiplying with white color produces no effect.
Color Burn
The foreground layer serves as a channelwise contrast modifier for the background layer: darker foreground colors increase the contrast in the background layer, making it darker. A completely black foreground results in maximum effect, while a completely white foreground produces no effect. Technically, this blending mode is equivalent to a channelwise Levels operation on the R, G and B channels of the Background layer, where the Black Point input for each channel is mapped with the inverted corresponding channel taken from Foreground.
Linear Burn
The foreground layer serves as a channelwise brightness modifier for the background layer: darker foreground colors decrease the brightness in the background layer. A completely black foreground results in black, while a completely white foreground produces no effect. Technically, the output image is produced by summing the R, G and B channels of the Background and Foreground layers and subtracting the white color from the result.
Lighten
Compares the values of R, G and B channels for both the foreground and background layers and selects the greater value for each channel. The three selected values are combined into a color to produce the result.
Screen
Lightens the background layer based on the lightness of the foreground layer. The result is lighter than both original images. Screening any source with black color produces no effect, and screening with white color produces white. Technically, the output image is produced by inverting the R, G and B channels of the Background and Foreground layers, multiplying them as described in the Multiply mode above, and inverting the result.
Color Dodge
The foreground layer serves as a channelwise contrast modifier for the background layer: brighter foreground colors increase the contrast in the background layer, making it brighter. A completely white foreground results in maximum effect, while a completely black foreground produces no effect. Technically, this blending mode is equivalent to a channelwise Levels operation on the R, G and B channels of the Background layer, where the White Point input for each channel is mapped with the inverted corresponding channel taken from Foreground.
Linear Dodge
Sums the values of R, G and B channels for both the foreground and background layers. The result is brighter than both original images. Combining any source with black color produces no effect, and combining with white color produces white.
Overlay
Combines the Multiply and Screen modes. The mode is selected depending on the RGB channel levels of the background layer: if a channel level is lower than 50%, the Multiply mode is selected, if it is greater than 50%, the Screen mode is selected.
Soft Light
Darkens or lightens the background layer depending on the foreground layer, imitating the effect of a diffused light source. The result is similar to a channelwise Gamma adjustment of the background layer where the gamma values are determined by the channel levels of the foreground layer. If the foreground color (light source) is lighter than 50% gray, the image is lightened, if the foreground color is darker than 50% gray, the image is darkened. The foreground of 50% gray produces no effect.
Hard Light
Combines the Multiply and Screen modes. Unlike Overlay, the mode is selected depending on the RGB channel levels of the foreground layer (Overlay uses the background). If a channel level is lower than 50%, the Multiply mode is selected, if it is greater than 50%, the Screen mode is selected.
Vivid Light
Combines the Color Burn and Color Dodge modes. The mode is selected depending on the RGB channel levels of the foreground layer: if a channel level is lower than 50%, the Color Burn mode is selected, if it is greater than 50%, the Color Dodge mode is selected.
Linear Light
Combines the Linear Dodge and Linear Burn modes. The mode is selected depending on the RGB channel levels of the foreground layer: if a channel level is lower than 50%, the Linear Burn mode is selected, if it is greater than 50%, the Linear Dodge mode is selected.
Difference
Shows the difference between the foreground and background layers. If both layers are identical, the result will be completely black. Combining any source with black color produces no effect, and combining with white color inverts the color values of the source. Technically, the result is an absolute value of a channelwise difference between the RGB channel values of both layers.
Hue
Assembles the result from the lightness and saturation of the background layer and the hue of the foreground layer according to the HSY color model.
Saturation
Assembles the result from the lightness and hue of the background layer and the saturation of the foreground layer according to the HSY color model.
Color
Assembles the result from the lightness of the background layer and the hue and saturation of the foreground layer according to the HSY color model.
Luminosity
Assembles the result from the hue and saturation of the background layer and the lightness of the foreground layer according to the HSY color model.
