| 123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354 |
- 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;
|