Web SDK Assembly

Barcode Decoder WebAssembly (datasymbol-sdk.wasm file) provides the low level interface. You can write your own JavaScript code (instead our DSScanner) that works directly with WebAssembly.

InitLib

Initialize WebAssembly library.

Syntax

object.InitLib(pszKey)

Parameters

pszKey Pointer to the null-terminated string with library key. If parameter is NULL then library will work in demo mode.

Return Value

long. Returns the HANDLE of barcode decoder. You should to save this value to use it in future. If returns NULL then SDK cannot be initialized.

Remarks

This method should be called before any else. To free the library you should to call FreeLib

FreeLib

Release WebAssembly library.

Syntax

object.FreeLib(decHandle)

Parameters

decHandle HANDLE of barcode decoder returned by InitLib method.

Return Value

integer. Returns the Error Code.

DecodeRGBA

Decodes the RGBA encoded image.

Syntax

object.DecodeRGBA(decHandle, pRGBA, width, height)

Parameters

decHandle HANDLE of barcode decoder returned by InitLib method.

pRGBA Pointer to the byte array containded RGBA image

width An integer value that defines the width of RGBA image

height An integer value that defines the height of RGBA image

Return Value

integer. Returns the Error Code.

DecodeGraymap

Decodes the gray map.

Syntax

object.DecodeGraymap(decHandle, pImg, width, height)

Parameters

decHandle HANDLE of barcode decoder returned by InitLib method.

pImg Pointer to the byte array containded gray map.

width An integer value that defines the width of the gray map image

height An integer value that defines the height of gray map image

Return Value

integer. Returns the Error Code.

Remarks

A gray map is a byte matrix. Each byte has the value from 0 to 255 and represents one image pixel. 0 means a black pixel, 255 means a white pixel. The matrix is passed to the DecodeGrayMap method as a one-dimensional array. The first upper line of the image is sent first, then comes the second line and so on.

DecodePGM

Decodes the PGM (portable gray map) file.

Syntax

object.DecodePGM(decHandle, pImg, width, height)

Parameters

decHandle HANDLE of barcode decoder returned by InitLib method.

pPGM Pointer to the byte array containded the whole PGM file.

pgmLen An integer value that defines the PGM file length

Return Value

integer. Returns the Error Code.

setProperty

Sets the various properties of Barcode Decoder.

Syntax

object.setProperty(decHandle, pszPropName, pData)

Parameters

decHandle HANDLE of barcode decoder returned by InitLib method.

pszPropName Pointer to the null-terminated string that defines the Propery name.

pData Pointer to byte array that defines the property value. Length of byte array depends from property.

Properties

Name Value

barcodeTypes 4 bytes. what types of barcodes should be decoded.

totalBarcodes 4 bytes. how many barcodes of all types to search for in the entire document.
Default value - 0 (unlimited)

frameTime 4 bytes. Time to decode 1 frame in milliseconds.
Default value - 0 (unlimited).

bCalcBlurring 4 bytes boolean. calculate the blurring value of decoded barcode (default - false).

scanDirection 4 bytes. Scanning direction, horizontaly (1) or verticaly (2). You can use it to reduce the barcode decoding time
Default value - 3 (horizontaly and verticaly).

uiLinearFindBarcodes 4 bytes. how many Linear barcodes to search
Default value - 1

bLinearVerifyCheckDigit 4 bytes boolean. Check the optional Linear check digit
Default value - 0 (false)

bLinearShowCheckDigit 4 bytes boolean. Show Linear check digit
Default value - 1 (true)

bLinearShowStartStop 4 bytes boolean. Show Linear check digit
Default value - 0 (false)

bLinearVerify 4 bytes boolean. Verify linear barcode after decoding. Improves reliability linear barcode reading.
Default value - False (don't verify).

bLinearCode39EnableExtended 4 bytes boolean. Decode Code 39 as Code 39 Extended or not.
Default value - 0 (false)

bLinearUPCE2UPCA 4 bytes boolean. Convert a UPC-E barcode to UPC-A or not.
Default value - 0 (false)

uiLinearInterl25MinLen 4 bytes. minimum length of an Interleaved 2/5 barcode
Default value - 2

uiLinearInterl25MaxLen 4 bytes. miximum length of an Interleaved 2/5 barcode
Default value - 50

uiLinearIndustr25MinLen 4 bytes. minimum length of an Industrial 2/5 barcode
Default value - 1

uiLinearIndustr25MaxLen 4 bytes. miximum length of an Industrial 2/5 barcode
Default value - 50

uiLinearCode11MinLen 4 bytes. minimum length of an Code 11 barcode
Default value - 1

uiLinearCode11MaxLen 4 bytes. miximum length of an Code 11 barcode
Default value - 50

uiLinearCode39MinLen 4 bytes. minimum length of an Code 39 barcode
Default value - 1

uiLinearCode39MaxLen 4 bytes. miximum length of an Code 39 barcode
Default value - 50

uiLinearCode128MinLen 4 bytes. minimum length of an Code 128 barcode
Default value - 1

uiLinearCode128MaxLen 4 bytes. miximum length of an Code 128 barcode
Default value - 50

uiLinearCodabarMinLen 4 bytes. minimum length of an Codabar barcode
Default value - 1

uiLinearCodabarMaxLen 4 bytes. miximum length of an Codabar barcode
Default value - 50

uiLinearCode93MinLen 4 bytes. minimum length of an Code 93 barcode
Default value - 1

uiLinearCode93MaxLen 4 bytes. miximum length of an Code 93 barcode
Default value - 50

LinearDecSpeed 4 bytes. Speed of Linear barcode decoder
Default value - 0
Possible values:
0 - Normal
1 - Fast
2 - Slow

uiPDF417FindBarcodes 4 bytes. how many PDF417 barcodes to search
Default value - 1

PDF417DecSpeed 4 bytes. Speed of PDF417 barcode decoder
Default value - 0
Possible values:
0 - Normal
1 - Fast
2 - Slow

bPDF417FindMicro 4 bytes boolean. Search PDF417 Micro barcodes
Default value - 0 (false)

bPDF417SupportECI 4 bytes boolean. Support PDF417 ECI
Default value - 0 (false)

bPDF417Robust 4 bytes boolean. Robust PDF417 decoding
Default value - 0 (false)

uiDataMatrixFindBarcodes 4 bytes. how many DataMatrix barcodes to search
Default value - 1

DataMatrixDecSpeed 4 bytes. Speed of DataMatrix barcode decoder
Default value - 0
Possible values:
0 - Normal
1 - Fast
2 - Slow

DataMatrixInverseType 4 bytes. what barcodes should be decoded (darks on light or lights on dark).
Default value - (1) darks on light
2-light on dark, 3-light and dark

bDataMatrixSupportECI 4 bytes boolean. Support DataMatrix ECI
Default value - 0 (false)

DataMatrixDecMirror 4 bytes. Normal/Mirror DataMatrix decoding
Default value - 0
Possible values:
0 - only Normal
1 - only Mirror
2 - Normal and Mirror

uiQRCodeFindBarcodes 4 bytes. how many QRCode barcodes to search
Default value - 1

QRCodeDecSpeed 4 bytes. Speed of QRCode barcode decoder
Default value - 0
Possible values:
0 - Normal
1 - Fast
2 - Slow

bQRCodeFindMicro 4 bytes boolean. Search Micro QRCode
Default value - 0 (false)

QRCodeDecMirror 4 bytes. Normal/Mirror QRCode decoding
Default value - 0
Possible values:
0 - only Normal
1 - only Mirror
2 - Normal and Mirror

uiAztecCodeFindBarcodes 4 bytes. how many AztecCode barcodes to search
Default value - 1

AztecCodeDecSpeed 4 bytes. Speed of AztecCode barcode decoder
Default value - 0
Possible values:
0 - Normal
1 - Fast
2 - Slow

ScanningRectLeft 4 bytes. Left coordinate of scanning area. It works when all ScanningRectX parameters are correct

ScanningRectTop 4 bytes. Top coordinate of scanning area

ScanningRectWidth 4 bytes. Width of scanning area

ScanningRectHeight 4 bytes. Height of scanning area

Return Value

integer. Returns the Error Code.

getResNum

Gets the number of decoded barcodes.

Syntax

object.getResNum(decHandle)

Parameters

decHandle HANDLE of barcode decoder returned by InitLib method.

Return Value

integer. If less than 0 then it returns the Error Code, else the barcode number.

getResBarcodeType

Gets the barcode type.

Syntax

object.getResBarcodeType(decHandle, barcodeNum)

Parameters

decHandle HANDLE of barcode decoder returned by InitLib method.

barcodeNum integer value that defines the barcode number.

Return Value

integer. If less than 0 then it returns the Error Code, else the barcode type.

getResDQ

Gets the decoding quality.

Syntax

object.getResDQ(decHandle, barcodeNum)

Parameters

decHandle HANDLE of barcode decoder returned by InitLib method.

barcodeNum integer value that defines the barcode number.

Return Value

integer. If less than 0 then it returns the Error Code, else the decoding quality (0...100).

getResData

Gets the barcode data.

Syntax

object.getResData(decHandle, pOutBuf, bufLen, barcodeNum)

Parameters

decHandle HANDLE of barcode decoder returned by InitLib method.

pOutBuf pointer to the outer buffer

bufLen outer buffer length

barcodeNum integer value that defines the barcode number.

Return Value

integer. If less than 0 then it returns the Error Code, else the barcode data.

getResPoints

Gets the barcode corners coordinates.

Syntax

object.getResPoints(decHandle, pOutBuf, bufLen, barcodeNum)

Parameters

decHandle HANDLE of barcode decoder returned by InitLib method.

pOutBuf pointer to the outer buffer

bufLen outer buffer length

barcodeNum integer value that defines the barcode number.

Return Value

integer. Returns the Error Code.

Remarks

Method copies in the pOutBuf 8 integer (32 bit) values. 0 value - x1 coordinate, 1 value - y1 coordinate, 2 value - x2 coordinate, 3 value - y2 coordinate, etc.

Error Codes

0 Ok

1 Error

2 invalid decoder handle

3 invalid parameter

4 invalid barcode number

5 not enought memory

6 unknown property

Barcode Types

0x00000001 Code 128

0x00000002 Code 39

0x00000004 Interleaved 2/5

0x00000008 EAN-13

0x00000010 EAN-8

0x00000020 Codabar

0x00000040 Code 11

0x00000080 UPC-A

0x00000100 UPC-E

0x00000200 Industrial 2/5

0x00000400 Code 93

0x00000800 DataBar omnidirectional, DataBar Truncated

0x00001000 DataBar limited

0x00002000 DataBar stacked

0x00004000 DataBar Expanded

0x00008000 DataBar Expanded stacked

0x01000000 unrecognized linear

0x02000000 unrecognized PDF417

0x04000000 unrecognized DataMatrix

0x08000000 unrecognized QRCode

0x00100000 unrecognized AztecCode

0x10000000 DataMatrix

0x20000000 PDF417

0x40000000 QRCode

0x80000000 AztecCode