Interface ReaderOptions

Reader options for reading barcodes.

interface ReaderOptions {
    binarizer?:
        | "LocalAverage"
        | "GlobalHistogram"
        | "FixedThreshold"
        | "BoolCast";
    characterSet?: | "Unknown"
    | "ASCII"
    | "ISO8859_1"
    | "ISO8859_2"
    | "ISO8859_3"
    | "ISO8859_4"
    | "ISO8859_5"
    | "ISO8859_6"
    | "ISO8859_7"
    | "ISO8859_8"
    | "ISO8859_9"
    | "ISO8859_10"
    | "ISO8859_11"
    | "ISO8859_13"
    | "ISO8859_14"
    | "ISO8859_15"
    | "ISO8859_16"
    | "Cp437"
    | "Cp1250"
    | "Cp1251"
    | "Cp1252"
    | "Cp1256"
    | "Shift_JIS"
    | "Big5"
    | "GB2312"
    | "GB18030"
    | "EUC_JP"
    | "EUC_KR"
    | "UTF16BE"
    | "UTF8"
    | "UTF16LE"
    | "UTF32BE"
    | "UTF32LE"
    | "BINARY";
    downscaleFactor?: number;
    downscaleThreshold?: number;
    eanAddOnSymbol?: "Ignore"
    | "Read"
    | "Require";
    formats?: ReadInputBarcodeFormat[];
    isPure?: boolean;
    maxNumberOfSymbols?: number;
    minLineCount?: number;
    returnErrors?: boolean;
    textMode?: "Plain" | "ECI" | "HRI" | "Hex" | "Escaped";
    tryCode39ExtendedMode?: boolean;
    tryDenoise?: boolean;
    tryDownscale?: boolean;
    tryHarder?: boolean;
    tryInvert?: boolean;
    tryRotate?: boolean;
}

Hierarchy

  • Partial<
        Omit<
            ZXingReaderOptions,
            "formats"
            | "binarizer"
            | "eanAddOnSymbol"
            | "textMode"
            | "characterSet",
        >,
    >
    • ReaderOptions

Properties

binarizer? characterSet? downscaleFactor? downscaleThreshold? eanAddOnSymbol? formats? isPure? maxNumberOfSymbols? minLineCount? returnErrors? textMode? tryCode39ExtendedMode? tryDenoise? tryDownscale? tryHarder? tryInvert? tryRotate?

Properties

Optionalbinarizer

binarizer?: "LocalAverage" | "GlobalHistogram" | "FixedThreshold" | "BoolCast"

Algorithm to use for the grayscale to binary transformation. The difference is how to get to a threshold value T which results in a bit value R = L <= T.

  • "LocalAverage"

    T = average of neighboring pixels for matrix and GlobalHistogram for linear (HybridBinarizer)

  • "GlobalHistogram"

    T = valley between the 2 largest peaks in the histogram (per line in linear case)

  • "FixedThreshold"

    T = 127

  • "BoolCast"

    T = 0, fastest possible

Default Value

"LocalAverage"

OptionalcharacterSet

characterSet?:
    | "Unknown"
    | "ASCII"
    | "ISO8859_1"
    | "ISO8859_2"
    | "ISO8859_3"
    | "ISO8859_4"
    | "ISO8859_5"
    | "ISO8859_6"
    | "ISO8859_7"
    | "ISO8859_8"
    | "ISO8859_9"
    | "ISO8859_10"
    | "ISO8859_11"
    | "ISO8859_13"
    | "ISO8859_14"
    | "ISO8859_15"
    | "ISO8859_16"
    | "Cp437"
    | "Cp1250"
    | "Cp1251"
    | "Cp1252"
    | "Cp1256"
    | "Shift_JIS"
    | "Big5"
    | "GB2312"
    | "GB18030"
    | "EUC_JP"
    | "EUC_KR"
    | "UTF16BE"
    | "UTF8"
    | "UTF16LE"
    | "UTF32BE"
    | "UTF32LE"
    | "BINARY"

Character set to use (when applicable). If this is set to "Unknown", auto-detecting will be used.

Default Value

"Unknown"

Optional ExperimentaldownscaleFactor

downscaleFactor?: number

Scale factor to use during downscaling, meaningful values are 2, 3 and 4.

WARNING: this API is experimental and may change / disappear

Default Value

3

See

tryDownscale downscaleThreshold

Optional ExperimentaldownscaleThreshold

downscaleThreshold?: number

Image size min(width, height) threshold at which to start downscaled scanning.

WARNING: this API is experimental and may change / disappear

Default Value

500

See

tryDownscale downscaleFactor

OptionaleanAddOnSymbol

eanAddOnSymbol?: "Ignore" | "Read" | "Require"

Specify whether to ignore, read or require EAN-2 / 5 add-on symbols while scanning EAN / UPC codes.

  • "Ignore"

    Ignore any Add-On symbol during read / scan

  • "Read"

    Read EAN-2 / EAN-5 Add-On symbol if found

  • "Require"

    Require EAN-2 / EAN-5 Add-On symbol to be present

Default Value

"Ignore"

Optionalformats

formats?: ReadInputBarcodeFormat[]

A set of ReadInputBarcodeFormats that should be searched for. An empty list [] indicates all supported formats.

Supported values in this list are: "Aztec", "Codabar", "Code39", "Code93", "Code128", "DataBar", "DataBarExpanded", "DataBarLimited", "DataMatrix", "DXFilmEdge", "EAN-8", "EAN-13", "ITF", "MaxiCode", "MicroQRCode", "PDF417", "QRCode", "rMQRCode", "UPC-A", "UPC-E", "Linear-Codes", "Matrix-Codes", Any

Default Value

[]

OptionalisPure

isPure?: boolean

Set to true if the input contains nothing but a single perfectly aligned barcode (usually generated images).

Default Value

false

OptionalmaxNumberOfSymbols

maxNumberOfSymbols?: number

The maximum number of symbols / barcodes to detect / look for in the image. The upper limit of this number is 255.

Default Value

255

OptionalminLineCount

minLineCount?: number

The number of scan lines in a linear barcode that have to be equal to accept the result.

Default Value

2

OptionalreturnErrors

returnErrors?: boolean

If true, return the barcodes with errors as well (e.g. checksum errors).

Default Value

false

See

ReadResult.error

OptionaltextMode

textMode?: "Plain" | "ECI" | "HRI" | "Hex" | "Escaped"

Specifies the TextMode that controls the result of ReadResult.text.

  • "Plain"

    ReadResult.bytes transcoded to unicode based on ECI info or guessed character set

  • "ECI"

    Standard content following the ECI protocol with every character set ECI segment transcoded to unicode

  • "HRI"

    Human Readable Interpretation (dependent on the ContentType)

  • "Hex"

    ReadResult.bytes transcoded to ASCII string of HEX values

  • "Escaped"

    Escape non-graphical characters in angle brackets (e.g. ASCII 29 will be transcoded to "<GS>")

Default Value

"HRI"

OptionaltryCode39ExtendedMode

tryCode39ExtendedMode?: boolean

Enable the heuristic to detect and decode "full ASCII" / extended Code39 symbols.

Default Value

true

Optional ExperimentaltryDenoise

tryDenoise?: boolean

Try detecting code after denoising (currently morphological closing filter for 2D symbologies only).

Default Value

false

OptionaltryDownscale

tryDownscale?: boolean

Try detecting code in downscaled images (depending on image size).

Default Value

true

See

downscaleFactor downscaleThreshold

OptionaltryHarder

tryHarder?: boolean

Spend more time to try to find a barcode. Optimize for accuracy, not speed.

Default Value

true

OptionaltryInvert

tryInvert?: boolean

Try detecting inverted (reversed reflectance) codes if the format allows for those.

Default Value

true

OptionaltryRotate

tryRotate?: boolean

Try detecting code in 90, 180 and 270 degree rotated images.

Default Value

true

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