Blend(ImGearRasterPage,Int32,Int32,ImGearRasterPage,Double) Method

Blends two images based on the weight (in percents) of the secondary image.

Syntax

Visual Basic
C#
Managed Extensions for C++
C++/CLI

'Declaration
 
Public Overloads Shared Sub Blend( _
   ByVal page As ImGearRasterPage, _
   ByVal left As Integer, _
   ByVal top As Integer, _
   ByVal pageToBlendWith As ImGearRasterPage, _
   ByVal weight As Double _
)

'Usage
 
Dim page As ImGearRasterPage
Dim left As Integer
Dim top As Integer
Dim pageToBlendWith As ImGearRasterPage
Dim weight As Double
 
ImGearRasterProcessing.Blend(page, left, top, pageToBlendWith, weight)

public static void Blend( 
   ImGearRasterPage page,
   int left,
   int top,
   ImGearRasterPage pageToBlendWith,
   double weight
)

public: static void Blend( 
   ImGearRasterPage* page,
   int left,
   int top,
   ImGearRasterPage* pageToBlendWith,
   double weight
)

public:
static void Blend( 
   ImGearRasterPage^ page,
   int left,
   int top,
   ImGearRasterPage^ pageToBlendWith,
   double weight
)

Parameters

page: Page to process.
left: Left margin of blended image.
top: Top margin of blended image.
pageToBlendWith: Image to blend with page.
weight: A value from 0 to 100 defining the % weight of the pageToBlendWith image to be blended.

Remarks

This method blends all channels of page with corresponding channels of pageToBlendWith, using the following formula:

pagePixel = (pagePixel * (100.0 - weight) + pageToBlendPixel * weight) / 100.0

The method validates input pages for further processing according to following logics:

This method is applicable to any colorspace, but both images must have the same base colorspace (i.e. upon validation of input images will be considered color channels only - Alpha or Extra channels will be ignored. So, for example, any combination of pages with RGB(A/Ex) colorspaces (e.g. RGB and RGBA) are valid input parameters).
This method is applicable to any supported by ImageGear channel depth for given colorspace, but channel depths of both images must be the same.

The method processes the input pages according to following logics:

This method processes all channels of input pages. In order to process a specific group of image channels, e.g. color channels only, use another overload Blend(ImGearRasterPage,Int32,Int32,ImGearRasterPage,Double,ImGearChannelRange).
If page and pageToBlendWith have different number of channels, the method blends the minimal number of channels between the images. For example, for images with RGB and RGBEx colorspaces will be processed 3 channels. The remaining redundant channels will be handled as following:
- If page has more channels than pageToBlendWith (an Alpha or Extras), they will remain intact.
- If pageToBlendWith has more channels than page (an Alpha or Extras), they will be ignored.
This method does not not provide any special handling for the Alpha channel (i.e. it processes it as ordinary color channel), please use BlendWithAlpha method to blend images using the Alpha channel.

Example

// Opens an image and blends it into an already open image.
using (FileStream file = new FileStream("photo.jpg",
                   FileMode.Open, FileAccess.Read, FileShare.Read))
{
    ImGearRasterPage igPageToBlend = (ImGearRasterPage)
        ImGearFileFormats.LoadPage(file, 0);

    // Blend the page with a weight of 25% starting from the point 100,100.
    ImGearRasterProcessing.Blend(igRasterPage, 100, 100, igPageToBlend, 25.0);
}

Visual Basic

' Opens an image and blends it into an already open image.
Using file As New FileStream("photo.jpg", FileMode.Open, FileAccess.Read, FileShare.Read)
    Dim igPageToBlend As ImGearRasterPage = DirectCast(ImGearFileFormats.LoadPage(file, 0), ImGearRasterPage)

    ' Blend the page with a weight of 25% starting from the point 100,100.
    ImGearRasterProcessing.Blend(igRasterPage, 100, 100, igPageToBlend, 25)
End Using

Reference

ImGearRasterProcessing Class
ImGearRasterProcessing Members
Overload List
BlendWithAlpha Method
ImGearRasterPage Class