@zxing/library/es2015/core/Binarizer.d.ts

TypeScript port of ZXing multi-format 1D/2D barcode image processing library.

import LuminanceSource from './LuminanceSource';
import BitArray from './common/BitArray';
import BitMatrix from './common/BitMatrix';
/**
 * This class hierarchy provides a set of methods to convert luminance data to 1 bit data.
 * It allows the algorithm to vary polymorphically, for example allowing a very expensive
 * thresholding technique for servers and a fast one for mobile. It also permits the implementation
 * to vary, e.g. a JNI version for Android and a Java fallback version for other platforms.
 *
 * @author dswitkin@google.com (Daniel Switkin)
 */
declare abstract class Binarizer {
    private source;
    protected constructor(source: LuminanceSource);
    getLuminanceSource(): LuminanceSource;
    /**
     * 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.
     *
     * @param y The row to fetch, which must be in [0, bitmap height)
     * @param row An optional preallocated array. If null or too small, it will be ignored.
     *            If used, the Binarizer will call BitArray.clear(). Always use the returned object.
     * @return The array of bits for this row (true means black).
     * @throws NotFoundException if row can't be binarized
     */
    abstract getBlackRow(y: number, row: BitArray): BitArray;
    /**
     * 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.
     *
     * @return The 2D array of bits for the image (true means black).
     * @throws NotFoundException if image can't be binarized to make a matrix
     */
    abstract getBlackMatrix(): BitMatrix;
    /**
     * 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.
     *
     * @param source The LuminanceSource this Binarizer will operate on.
     * @return A new concrete Binarizer implementation object.
     */
    abstract createBinarizer(source: LuminanceSource): Binarizer;
    getWidth(): number;
    getHeight(): number;
}
export default Binarizer;