GlobalHistogramBinarizer class

This Binarizer implementation uses the old ZXing global histogram approach. It is suitable for low-end mobile devices which don't have enough CPU or memory to use a local thresholding algorithm. However, because it picks a global black point, it cannot handle difficult shadows and gradients.

Faster mobile devices and all desktop applications should probably use HybridBinarizer instead.

@author [e-mail] (Daniel Switkin) @author Sean Owen

Inheritance

• Object
• Binarizer
• GlobalHistogramBinarizer

Implementers

• HybridBinarizer

Constructors

GlobalHistogramBinarizer(LuminanceSource source)

Properties

hashCode → int

The hash code for this object.

no setter, inherited

height → int

no setter, inherited

luminanceSource → LuminanceSource

final, inherited

runtimeType → Type

A representation of the runtime type of the object.

no setter, inherited

width → int

no setter, inherited

Methods

createBinarizer(LuminanceSource source) → Binarizer

Creates a new object with the same type as this Binarizer implementation, but with pristine state. This is needed because Binarizer implementations may be stateful, e.g. keeping a cache of 1 bit data. See Effective Java for why we can't use Java's clone() method.

override

getBlackMatrix() → BitMatrix

Converts a 2D array of luminance data to 1 bit data. As above, assume this method is expensive and do not call it repeatedly. This method is intended for decoding 2D barcodes and may or may not apply sharpening. Therefore, a row from this matrix may not be identical to one fetched using getBlackRow(), so don't mix and match between them.

override

getBlackRow(int y, BitArray? row) → BitArray

Converts one row of luminance data to 1 bit data. May actually do the conversion, or return cached data. Callers should assume this method is expensive and call it as seldom as possible. This method is intended for decoding 1D barcodes and may choose to apply sharpening. For callers which only examine one row of pixels at a time, the same BitArray should be reused and passed in with each call for performance. However it is legal to keep more than one row at a time if needed.

override

noSuchMethod(Invocation invocation) → dynamic

Invoked when a nonexistent method or property is accessed.

inherited

toString() → String

A string representation of this object.

inherited

Operators

operator ==(Object other) → bool

The equality operator.

inherited