website/includes/qrcodedecoder/Zxing/Common/DefaultGridSampler.php

<?php
/*
* Copyright 2007 ZXing authors
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
*      http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/

namespace Zxing\Common;

use Zxing\NotFoundException;

/**
 * @author Sean Owen
 */
final class DefaultGridSampler extends GridSampler
{
//@Override
    public function sampleGrid(
        $image,
        $dimensionX,
        $dimensionY,
        $p1ToX, $p1ToY,
        $p2ToX, $p2ToY,
        $p3ToX, $p3ToY,
        $p4ToX, $p4ToY,
        $p1FromX, $p1FromY,
        $p2FromX, $p2FromY,
        $p3FromX, $p3FromY,
        $p4FromX, $p4FromY
    ) {

        $transform = PerspectiveTransform::quadrilateralToQuadrilateral(
            $p1ToX, $p1ToY, $p2ToX, $p2ToY, $p3ToX, $p3ToY, $p4ToX, $p4ToY,
            $p1FromX, $p1FromY, $p2FromX, $p2FromY, $p3FromX, $p3FromY, $p4FromX, $p4FromY);

        return $this->sampleGrid_($image, $dimensionX, $dimensionY, $transform);
    }

//@Override
    public function sampleGrid_(
        $image,
        $dimensionX,
        $dimensionY,
        $transform
    ) {
        if ($dimensionX <= 0 || $dimensionY <= 0) {
            throw NotFoundException::getNotFoundInstance();
        }
        $bits   = new BitMatrix($dimensionX, $dimensionY);
        $points = fill_array(0, 2 * $dimensionX, 0.0);
        for ($y = 0; $y < $dimensionY; $y++) {
            $max    = count($points);
            $iValue = (float)$y + 0.5;
            for ($x = 0; $x < $max; $x += 2) {
                $points[$x]     = (float)($x / 2) + 0.5;
                $points[$x + 1] = $iValue;
            }
            $transform->transformPoints($points);
// Quick check to see if points transformed to something inside the image;
// sufficient to check the endpoints
            $this->checkAndNudgePoints($image, $points);
            try {
                for ($x = 0; $x < $max; $x += 2) {
                    if ($image->get((int)$points[$x], (int)$points[$x + 1])) {
// Black(-ish) pixel
                        $bits->set($x / 2, $y);
                    }
                }
            } catch (\Exception $aioobe) {//ArrayIndexOutOfBoundsException
// This feels wrong, but, sometimes if the finder patterns are misidentified, the resulting
// transform gets "twisted" such that it maps a straight line of points to a set of points
// whose endpoints are in bounds, but others are not. There is probably some mathematical
// way to detect this about the transformation that I don't know yet.
// This results in an ugly runtime exception despite our clever checks above -- can't have
// that. We could check each point's coordinates but that feels duplicative. We settle for
// catching and wrapping ArrayIndexOutOfBoundsException.
                throw NotFoundException::getNotFoundInstance();
            }
        }

        return $bits;
    }
}