Public Overloads Function GetPixelData( _
   ByVal row As Integer, _
   ByVal column As Integer _
) As Byte()

Visual Basic (Usage)	Copy Code
Dim instance As RasterImage Dim row As Integer Dim column As Integer Dim value() As Byte   value = instance.GetPixelData(row, column)

public byte[] GetPixelData( 
   int row,
   int column
)

public:
array<byte>^ GetPixelData( 
   int row,
   int column
) 

Parameters

row

The zero-based row number of the pixel.

column

The zero-based column number of the pixel

Return Value

This example uses GetPixelData and SetPixelData methods to swap the R and G values for a particular pixel.

Visual Basic

Copy Code

Public Sub GetPixelDataExample()    RasterCodecs.Startup()    Dim codecs As RasterCodecs = New RasterCodecs()    ' Load the image    Dim image As RasterImage = codecs.Load(LeadtoolsExamples.Common.ImagesPath.Path + "IMAGE1.CMP")    If image.BitsPerPixel = 24 Then       Dim Data As Byte()       Dim Value As Byte       Dim Row As Integer = 10, Column As Integer = 20       Data = image.GetPixelData(Row, Column)       ' swap the R and B values       Value = Data(0)       Data(0) = Data(2)       Data(2) = Value       ' put back the transformed pixel       image.SetPixelData(Row, Column, Data)    End If    codecs.Save(image, LeadtoolsExamples.Common.ImagesPath.Path + "IMAGE1_GetPixelData.BMP", RasterImageFormat.Bmp, 0)    image.Dispose()    codecs.Dispose()    RasterCodecs.Shutdown() End Sub

C#

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public void GetPixelDataExample()  {     RasterCodecs.Startup();     RasterCodecs codecs = new RasterCodecs();     // Load the image     RasterImage image = codecs.Load(LeadtoolsExamples.Common.ImagesPath.Path + "IMAGE1.CMP");       if(image.BitsPerPixel == 24)     {        byte[] Data;        byte Value;        int Row = 10, Column = 20;          Data = image.GetPixelData(Row, Column);        // swap the R and B values        Value = Data[0]; Data[0] = Data[2]; Data[2] = Value;          // put back the transformed pixel        image.SetPixelData(Row, Column, Data);     }       codecs.Save(image, LeadtoolsExamples.Common.ImagesPath.Path + "IMAGE1_GetPixelData.BMP", RasterImageFormat.Bmp, 0);       image.Dispose();     codecs.Dispose();     RasterCodecs.Shutdown();  }

No transformations are performed on the pixel data.

This method should be called only for 8, 16, 24, 32, 48 and 64-bit images. It works as follows:

• For 8-bit images, this method will retrieve the palette index for the specified pixel.
• For 16-bit images, this method will retrieve the 2-byte value that forms the pixel.
  • For grayscale 16-bit images, the data will contain the gray value. RasterImage.LowBit and RasterImage.HighBit properties indicate the valid pixel data.
  • For color 16-bit images, the data contains packed 5-bit R, G and B values. The high bit contains the alpha information. The Order determines whether the data is RGB or BGR.
• For 24-bit images, this method will retrieve the 3 bytes containing the pixel color. The Order determines whether the data is RGB or BGR.
• For 32-bit images, this method will retrieve the 4 bytes containing the pixel color and alpha information. The first 3 bytes contain the pixel color. The The Order determines whether the data in the first 3 bytes is RGB or BGR. The 4th byte is the alpha channel information.
• For 48-bit images, this method will retrieve the 6 bytes containing the pixel color. The Order determines whether the data is RGB or BGR. Each color component is stored as a 16-bit value, where 0 corresponds to black and 0xFFFF corresponds to full white.
• For 64-bit images, this method will retrieve the 8 bytes containing the pixel color and alpha information. The Order determines whether the data in the first 6 bytes is RGB or BGR. Each color component is stored as a 16-bit value, where 0 corresponds to black and 0xFFFF corresponds to full white. The last two bytes contain the alpha information (also stored as a short value).

The minimum size of the returned byte array is calculated:

( + 7) / 8

You can use the SetPixelData method to assign the returned value to another pixel.

This method uses image coordinates to specify the pixel. Therefore, you must account for the view perspective of the image. If you specify a pixel that is outside the image or outside the region (if the image has one), this method throws an exception.

The SetPixelData method changes the data of the specified pixel.

For more information, refer to Introduction to Image Processing With LEADTOOLS.

For more information refer to Accounting for View Perspective.

Target Platforms: Microsoft .NET Framework 3.0, Windows XP, Windows Server 2003 family, Windows Server 2008 family

Reference