GdPictureImaging.GetPixelArrayByte Method

Stores into an array of byte each Blue, Green, Red and Alpha components of the pixel contained into an area of a GdPicture image.

public GdPictureStatus GetPixelArrayByte(
    int ImageID, 
    ref Byte arPixels, 
    int SrcLeft, 
    int SrcTop, 
    int Width, 
    int Height
);

Visual Basic

Public Function GetPixelArrayByte(
    ByVal ImageID As Integer, 
    ByRef arPixels() As Byte, 
    ByVal SrcLeft As Integer, 
    ByVal SrcTop As Integer, 
    ByVal Width As Integer, 
    ByVal Height As Integer
) As GdPictureStatus

Parameters

Parameters	Description
ImageID	GdPicture Image Identifier.
arPixels	Output parameter. Array of pixel data.
SrcLeft	The left source pixel of the area.
SrcTop	The top source pixel of the area.
Width	The width of the area in pixel.
Height	The height of the area in pixel.

Returns

A member of the GdPictureStatus enumeration.

Related Topics

SetPixelArrayByte

Example

usage of GetPixelArrayByte() and SetPixelArrayByte() functions to apply negative effect on a GdPicture image

Copy Code

Dim oGdPictureImaging As New GdPictureImaging
Dim arPixel() As Byte
Dim X As Integer
Dim Y As Integer
Dim ImageID As Integer
Dim ImageHeight As Integer
Dim ImageWidth As Integer
 
oGdPictureImaging.SetLicenseNumber("XXX") 'Replace XXX by a demo or commercial license key
ImageID = oGdPictureImaging.CreateGdPictureImageFromFile("image.tif")
ImageHeight = oGdPictureImaging.GetHeight(ImageID)
ImageWidth = oGdPictureImaging.GetWidth(ImageID)
 
ReDim arPixel(ImageWidth * ImageHeight * 4)
oGdPictureImaging.GetPixelArrayByte(ImageID, arPixel, 0, 0, ImageWidth, ImageHeight)
 
For X = 0 To ImageWidth - 1
    For Y = 0 To ImageHeight - 1
        arPixel((Y * 4 * ImageWidth) + X * 4) = Not arPixel((Y * 4 * ImageWidth) + X * 4) 'Blue channel
        arPixel((Y * 4 * ImageWidth) + X * 4 + 1) = Not arPixel((Y * 4 * ImageWidth) + X * 4 + 1) 'Green channel
        arPixel((Y * 4 * ImageWidth) + X * 4 + 2) = Not arPixel((Y * 4 * ImageWidth) + X * 4 + 2) 'Red channel
        arPixel((Y * 4 * ImageWidth) + X * 4 + 3) = 255 'Alpha chanel. Set 255 for full opacity
    Next Y
Next X
oGdPictureImaging.SetPixelArrayByte(ImageID, arPixel, 0, 0, ImageWidth, ImageHeight)
oGdPictureImaging.SaveAsTIFF(ImageID, "imageneg.tif", TiffCompression.TiffCompressionAUTO)
oGdPictureImaging.ReleaseGdPictureImage(ImageID)