import LuminanceSource from './LuminanceSource';
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import BitArray from './common/BitArray';
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import BitMatrix from './common/BitMatrix';
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/**
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* This class hierarchy provides a set of methods to convert luminance data to 1 bit data.
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* It allows the algorithm to vary polymorphically, for example allowing a very expensive
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* thresholding technique for servers and a fast one for mobile. It also permits the implementation
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* to vary, e.g. a JNI version for Android and a Java fallback version for other platforms.
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*
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* @author dswitkin@google.com (Daniel Switkin)
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*/
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declare abstract class Binarizer {
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private source;
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protected constructor(source: LuminanceSource);
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getLuminanceSource(): LuminanceSource;
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/**
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* Converts one row of luminance data to 1 bit data. May actually do the conversion, or return
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* cached data. Callers should assume this method is expensive and call it as seldom as possible.
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* This method is intended for decoding 1D barcodes and may choose to apply sharpening.
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* For callers which only examine one row of pixels at a time, the same BitArray should be reused
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* and passed in with each call for performance. However it is legal to keep more than one row
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* at a time if needed.
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*
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* @param y The row to fetch, which must be in [0, bitmap height)
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* @param row An optional preallocated array. If null or too small, it will be ignored.
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* If used, the Binarizer will call BitArray.clear(). Always use the returned object.
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* @return The array of bits for this row (true means black).
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* @throws NotFoundException if row can't be binarized
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*/
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abstract getBlackRow(y: number, row: BitArray): BitArray;
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/**
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* Converts a 2D array of luminance data to 1 bit data. As above, assume this method is expensive
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* and do not call it repeatedly. This method is intended for decoding 2D barcodes and may or
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* may not apply sharpening. Therefore, a row from this matrix may not be identical to one
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* fetched using getBlackRow(), so don't mix and match between them.
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*
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* @return The 2D array of bits for the image (true means black).
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* @throws NotFoundException if image can't be binarized to make a matrix
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*/
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abstract getBlackMatrix(): BitMatrix;
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/**
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* Creates a new object with the same type as this Binarizer implementation, but with pristine
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* state. This is needed because Binarizer implementations may be stateful, e.g. keeping a cache
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* of 1 bit data. See Effective Java for why we can't use Java's clone() method.
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*
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* @param source The LuminanceSource this Binarizer will operate on.
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* @return A new concrete Binarizer implementation object.
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*/
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abstract createBinarizer(source: LuminanceSource): Binarizer;
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getWidth(): number;
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getHeight(): number;
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}
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export default Binarizer;
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