@zxing/library/es2015/core/common/GridSampler.d.ts

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

import BitMatrix from './BitMatrix';
import PerspectiveTransform from './PerspectiveTransform';
/**
 * Implementations of this class can, given locations of finder patterns for a QR code in an
 * image, sample the right points in the image to reconstruct the QR code, accounting for
 * perspective distortion. It is abstracted since it is relatively expensive and should be allowed
 * to take advantage of platform-specific optimized implementations, like Sun's Java Advanced
 * Imaging library, but which may not be available in other environments such as J2ME, and vice
 * versa.
 *
 * The implementation used can be controlled by calling {@link #setGridSampler(GridSampler)}
 * with an instance of a class which implements this interface.
 *
 * @author Sean Owen
 */
declare abstract class GridSampler {
    /**
     * Samples an image for a rectangular matrix of bits of the given dimension. The sampling
     * transformation is determined by the coordinates of 4 points, in the original and transformed
     * image space.
     *
     * @param image image to sample
     * @param dimensionX width of {@link BitMatrix} to sample from image
     * @param dimensionY height of {@link BitMatrix} to sample from image
     * @param p1ToX point 1 preimage X
     * @param p1ToY point 1 preimage Y
     * @param p2ToX point 2 preimage X
     * @param p2ToY point 2 preimage Y
     * @param p3ToX point 3 preimage X
     * @param p3ToY point 3 preimage Y
     * @param p4ToX point 4 preimage X
     * @param p4ToY point 4 preimage Y
     * @param p1FromX point 1 image X
     * @param p1FromY point 1 image Y
     * @param p2FromX point 2 image X
     * @param p2FromY point 2 image Y
     * @param p3FromX point 3 image X
     * @param p3FromY point 3 image Y
     * @param p4FromX point 4 image X
     * @param p4FromY point 4 image Y
     *
     * @return {@link BitMatrix} representing a grid of points sampled from the image within a region
     *   defined by the "from" parameters
     *
     * @throws NotFoundException if image can't be sampled, for example, if the transformation defined
     *   by the given points is invalid or results in sampling outside the image boundaries
     */
    abstract sampleGrid(image: BitMatrix, dimensionX: number, dimensionY: number, p1ToX: number, p1ToY: number, p2ToX: number, p2ToY: number, p3ToX: number, p3ToY: number, p4ToX: number, p4ToY: number, p1FromX: number, p1FromY: number, p2FromX: number, p2FromY: number, p3FromX: number, p3FromY: number, p4FromX: number, p4FromY: number): BitMatrix;
    abstract sampleGridWithTransform(image: BitMatrix, dimensionX: number, dimensionY: number, transform: PerspectiveTransform): BitMatrix;
    /**
     * <p>Checks a set of points that have been transformed to sample points on an image against
     * the image's dimensions to see if the point are even within the image.</p>
     *
     * <p>This method will actually "nudge" the endpoints back onto the image if they are found to be
     * barely (less than 1 pixel) off the image. This accounts for imperfect detection of finder
     * patterns in an image where the QR Code runs all the way to the image border.</p>
     *
     * <p>For efficiency, the method will check points from either end of the line until one is found
     * to be within the image. Because the set of points are assumed to be linear, this is valid.</p>
     *
     * @param image image into which the points should map
     * @param points actual points in x1,y1,...,xn,yn form
     * @throws NotFoundException if an endpoint is lies outside the image boundaries
     */
    protected static checkAndNudgePoints(image: BitMatrix, points: Float32Array): void;
}
export default GridSampler;