Public Function Read( _
   ByVal image As RasterImage, _
   ByVal searchRectangle As Rectangle, _
   ByVal searchType As BarcodeSearchTypeFlags, _
   ByVal units As BarcodeUnit, _
   ByVal flags As BarcodeReadFlags, _
   ByVal multipleMaxCount As Integer, _
   ByVal code1d As Barcode1d, _
   ByVal codePdf As BarcodeReadPdf, _
   ByVal codeColor As BarcodeColor _
) As RasterCollection(Of BarcodeData)

Visual Basic (Usage)

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Dim instance As BarcodeEngine Dim image As RasterImage Dim searchRectangle As Rectangle Dim searchType As BarcodeSearchTypeFlags Dim units As BarcodeUnit Dim flags As BarcodeReadFlags Dim multipleMaxCount As Integer Dim code1d As Barcode1d Dim codePdf As BarcodeReadPdf Dim codeColor As BarcodeColor Dim value As RasterCollection(Of BarcodeData)   value = instance.Read(image, searchRectangle, searchType, units, flags, multipleMaxCount, code1d, codePdf, codeColor)

public RasterCollection<BarcodeData> Read( 
   RasterImage image,
   Rectangle searchRectangle,
   BarcodeSearchTypeFlags searchType,
   BarcodeUnit units,
   BarcodeReadFlags flags,
   int multipleMaxCount,
   Barcode1d code1d,
   BarcodeReadPdf codePdf,
   BarcodeColor codeColor
)

public:
RasterCollection<BarcodeData> Read( 
   RasterImage image,
   Rectangle searchRectangle,
   BarcodeSearchTypeFlags searchType,
   BarcodeUnit units,
   BarcodeReadFlags flags,
   int multipleMaxCount,
   Barcode1d^ code1d,
   BarcodeReadPdf^ codePdf,
   BarcodeColor^ codeColor
) 

Parameters

image

RasterImage referencing the bitmap that holds the image data.

searchRectangle

Rectangle that contains the search area for the barcodes. Pass Rectangle.Empty to search the whole image. If this parameter is Rectangle.Empty and the image does not have a region, the entire image will be searched. If this parameter is Rectangle.Empty and the image does have a region, only the region will be searched.

searchType

Type of barcode for which to search. You can combine values when appropriate, by using a bitwise OR (|).

units

Unit of measurement.

flags

Processing options. values can be combined when appropriate, by using a bitwise OR (|). Pass BarcodeReadFlags.None to get the default.

multipleMaxCount

Specifies the maximum number of barcodes to search. Pass 0 to read all barcodes in a specified search area.

code1d

Barcode1d class containing linear barcode options to be read.

codePdf

BarcodeReadPdf class containing PDF417 and MicroPDF417 barcode options to be read.

codeColor

BarcodeColor class containing bar and space colors to be read.

Return Value

This method supports all images currently supported by LEADTOOLS.

Use this method to recognize barcode data.

To determine whether a barcode element is duplicated or not, use BarcodeData.IsDuplicated property.

If the barcode is duplicated, you can get it by calling the BarcodeData.DuplicatedIndex method and to get the next duplicated barcode call the BarcodeData.GetNextDuplicated method.

If you know the index of a duplicated barcode, you can get the first duplicate of that barcode by calling the GetFirstDuplicatedIndex method.

When the flags parameter is set to BarcodeReadFlags.UseColors, then this method will use the codeColor parameter, otherwise the method will ignore it and use the default colors of black for bars and white for spaces.

Using colors does not apply for 1 bit per pixel images.

The BarcodeReadFlags.UseColors flag is used with all barcode types.

The BarcodeReadFlags.ReturnCheck flag is used only with reading linear barcodes.

The smallest Data Matrix symbol size is 40 pixels by 40 pixels.

It can be read using BarcodeSearchTypeFlags.DatamatrixReadSmall since this enables the reading of Data Matrix symbols that are between 20 to 40 pixels in size.

The Linear barcodes are not supported in UNICODE text.

Point p1, p2, p3, p4;
int nStartX = barData.Location.Left;
int nStartY = barData.Location.Top;
int nWidth  = barData.Location.Right - nStartX;
int nHeight = barData.Location.Bottom - nStartY;
p1.X = (nStartX And 0xffff);
p1.Y = (nStartX >> 16);
p2.X = (nStartY And 0xffff);
p2.Y = (nStartY >> 16);
p3.X = (nWidth And 0xffff);
p3.Y = (nWidth >> 16);
p4.X = (nHeight And 0xffff);
p4.Y = (nHeight >> 16);

Reading Linear Barcodes (1D):

A barcode is composed of a start mark, data, and the end mark. Reading barcodes from left to right (setting the Direction property to BarcodeDirectionFlags.LeftToRight value) or from right to left (setting the Direction property to BarcodeDirectionFlags.RightToLeft value) will produce the same result in most cases, because the barcode reader engine recognizes the start and end marks, and handles the data accordingly. For example, if BarcodeDirectionFlags.LeftToRight is used and the user reads barcodes from left to right (the barcode is not rotated), the engine will recognize the start mark first, then the data, and finally the end mark. But if the user reads barcodes from right to left (the barcode is rotated 180 degrees), the engine will first recognize the end mark, then read the (reverse-order) data, and then recognize the start mark. In this case, the engine will flip the data to normal (start/data/end) order.

Target Platforms: Microsoft .NET Framework 2.0, Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family

Reference