Examples with FinderPattern com.google.zxing.qrcode.detector.FinderPattern used on opensource projects

Example 6 with FinderPattern

use of com.google.zxing.qrcode.detector.FinderPattern in project weex-example by KalicyZhou.

the class MultiFinderPatternFinder method selectMutipleBestPatterns.

/**
   * @return the 3 best {@link FinderPattern}s from our list of candidates. The "best" are
   *         those that have been detected at least {@link #CENTER_QUORUM} times, and whose module
   *         size differs from the average among those patterns the least
   * @throws NotFoundException if 3 such finder patterns do not exist
   */
private FinderPattern[][] selectMutipleBestPatterns() throws NotFoundException {
    List<FinderPattern> possibleCenters = getPossibleCenters();
    int size = possibleCenters.size();
    if (size < 3) {
        // Couldn't find enough finder patterns
        throw NotFoundException.getNotFoundInstance();
    }
    /*
     * Begin HE modifications to safely detect multiple codes of equal size
     */
    if (size == 3) {
        return new FinderPattern[][] { new FinderPattern[] { possibleCenters.get(0), possibleCenters.get(1), possibleCenters.get(2) } };
    }
    // Sort by estimated module size to speed up the upcoming checks
    Collections.sort(possibleCenters, new ModuleSizeComparator());
    /*
     * Now lets start: build a list of tuples of three finder locations that
     *  - feature similar module sizes
     *  - are placed in a distance so the estimated module count is within the QR specification
     *  - have similar distance between upper left/right and left top/bottom finder patterns
     *  - form a triangle with 90° angle (checked by comparing top right/bottom left distance
     *    with pythagoras)
     *
     * Note: we allow each point to be used for more than one code region: this might seem
     * counterintuitive at first, but the performance penalty is not that big. At this point,
     * we cannot make a good quality decision whether the three finders actually represent
     * a QR code, or are just by chance layouted so it looks like there might be a QR code there.
     * So, if the layout seems right, lets have the decoder try to decode.     
     */
    // holder for the results
    List<FinderPattern[]> results = new ArrayList<>();
    for (int i1 = 0; i1 < (size - 2); i1++) {
        FinderPattern p1 = possibleCenters.get(i1);
        if (p1 == null) {
            continue;
        }
        for (int i2 = i1 + 1; i2 < (size - 1); i2++) {
            FinderPattern p2 = possibleCenters.get(i2);
            if (p2 == null) {
                continue;
            }
            // Compare the expected module sizes; if they are really off, skip
            float vModSize12 = (p1.getEstimatedModuleSize() - p2.getEstimatedModuleSize()) / Math.min(p1.getEstimatedModuleSize(), p2.getEstimatedModuleSize());
            float vModSize12A = Math.abs(p1.getEstimatedModuleSize() - p2.getEstimatedModuleSize());
            if (vModSize12A > DIFF_MODSIZE_CUTOFF && vModSize12 >= DIFF_MODSIZE_CUTOFF_PERCENT) {
                // any more interesting elements for the given p1.
                break;
            }
            for (int i3 = i2 + 1; i3 < size; i3++) {
                FinderPattern p3 = possibleCenters.get(i3);
                if (p3 == null) {
                    continue;
                }
                // Compare the expected module sizes; if they are really off, skip
                float vModSize23 = (p2.getEstimatedModuleSize() - p3.getEstimatedModuleSize()) / Math.min(p2.getEstimatedModuleSize(), p3.getEstimatedModuleSize());
                float vModSize23A = Math.abs(p2.getEstimatedModuleSize() - p3.getEstimatedModuleSize());
                if (vModSize23A > DIFF_MODSIZE_CUTOFF && vModSize23 >= DIFF_MODSIZE_CUTOFF_PERCENT) {
                    // any more interesting elements for the given p1.
                    break;
                }
                FinderPattern[] test = { p1, p2, p3 };
                ResultPoint.orderBestPatterns(test);
                // Calculate the distances: a = topleft-bottomleft, b=topleft-topright, c = diagonal
                FinderPatternInfo info = new FinderPatternInfo(test);
                float dA = ResultPoint.distance(info.getTopLeft(), info.getBottomLeft());
                float dC = ResultPoint.distance(info.getTopRight(), info.getBottomLeft());
                float dB = ResultPoint.distance(info.getTopLeft(), info.getTopRight());
                // Check the sizes
                float estimatedModuleCount = (dA + dB) / (p1.getEstimatedModuleSize() * 2.0f);
                if (estimatedModuleCount > MAX_MODULE_COUNT_PER_EDGE || estimatedModuleCount < MIN_MODULE_COUNT_PER_EDGE) {
                    continue;
                }
                // Calculate the difference of the edge lengths in percent
                float vABBC = Math.abs((dA - dB) / Math.min(dA, dB));
                if (vABBC >= 0.1f) {
                    continue;
                }
                // Calculate the diagonal length by assuming a 90° angle at topleft
                float dCpy = (float) Math.sqrt(dA * dA + dB * dB);
                // Compare to the real distance in %
                float vPyC = Math.abs((dC - dCpy) / Math.min(dC, dCpy));
                if (vPyC >= 0.1f) {
                    continue;
                }
                // All tests passed!
                results.add(test);
            }
        // end iterate p3
        }
    // end iterate p2
    }
    if (!results.isEmpty()) {
        return results.toArray(new FinderPattern[results.size()][]);
    }
    // Nothing found!
    throw NotFoundException.getNotFoundInstance();
}

Example 7 with FinderPattern

use of com.google.zxing.qrcode.detector.FinderPattern in project android-zxing by PearceXu.

the class MultiFinderPatternFinder method selectMutipleBestPatterns.

/**
 * @return the 3 best {@link FinderPattern}s from our list of candidates. The "best" are
 *         those that have been detected at least {@link #CENTER_QUORUM} times, and whose module
 *         size differs from the average among those patterns the least
 * @throws NotFoundException if 3 such finder patterns do not exist
 */
private FinderPattern[][] selectMutipleBestPatterns() throws NotFoundException {
    List<FinderPattern> possibleCenters = getPossibleCenters();
    int size = possibleCenters.size();
    if (size < 3) {
        // Couldn't find enough finder patterns
        throw NotFoundException.getNotFoundInstance();
    }
    /*
     * Begin HE modifications to safely detect multiple codes of equal size
     */
    if (size == 3) {
        return new FinderPattern[][] { new FinderPattern[] { possibleCenters.get(0), possibleCenters.get(1), possibleCenters.get(2) } };
    }
    // Sort by estimated module size to speed up the upcoming checks
    Collections.sort(possibleCenters, new ModuleSizeComparator());
    /*
     * Now lets start: build a list of tuples of three finder locations that
     *  - feature similar module sizes
     *  - are placed in a distance so the estimated module count is within the QR specification
     *  - have similar distance between upper left/right and left top/bottom finder patterns
     *  - form a triangle with 90° angle (checked by comparing top right/bottom left distance
     *    with pythagoras)
     *
     * Note: we allow each point to be used for more than one code region: this might seem
     * counterintuitive at first, but the performance penalty is not that big. At this point,
     * we cannot make a good quality decision whether the three finders actually represent
     * a QR code, or are just by chance layouted so it looks like there might be a QR code there.
     * So, if the layout seems right, lets have the decoder try to decode.     
     */
    // holder for the results
    List<FinderPattern[]> results = new ArrayList<>();
    for (int i1 = 0; i1 < (size - 2); i1++) {
        FinderPattern p1 = possibleCenters.get(i1);
        if (p1 == null) {
            continue;
        }
        for (int i2 = i1 + 1; i2 < (size - 1); i2++) {
            FinderPattern p2 = possibleCenters.get(i2);
            if (p2 == null) {
                continue;
            }
            // Compare the expected module sizes; if they are really off, skip
            float vModSize12 = (p1.getEstimatedModuleSize() - p2.getEstimatedModuleSize()) / Math.min(p1.getEstimatedModuleSize(), p2.getEstimatedModuleSize());
            float vModSize12A = Math.abs(p1.getEstimatedModuleSize() - p2.getEstimatedModuleSize());
            if (vModSize12A > DIFF_MODSIZE_CUTOFF && vModSize12 >= DIFF_MODSIZE_CUTOFF_PERCENT) {
                // any more interesting elements for the given p1.
                break;
            }
            for (int i3 = i2 + 1; i3 < size; i3++) {
                FinderPattern p3 = possibleCenters.get(i3);
                if (p3 == null) {
                    continue;
                }
                // Compare the expected module sizes; if they are really off, skip
                float vModSize23 = (p2.getEstimatedModuleSize() - p3.getEstimatedModuleSize()) / Math.min(p2.getEstimatedModuleSize(), p3.getEstimatedModuleSize());
                float vModSize23A = Math.abs(p2.getEstimatedModuleSize() - p3.getEstimatedModuleSize());
                if (vModSize23A > DIFF_MODSIZE_CUTOFF && vModSize23 >= DIFF_MODSIZE_CUTOFF_PERCENT) {
                    // any more interesting elements for the given p1.
                    break;
                }
                FinderPattern[] test = { p1, p2, p3 };
                ResultPoint.orderBestPatterns(test);
                // Calculate the distances: a = topleft-bottomleft, b=topleft-topright, c = diagonal
                FinderPatternInfo info = new FinderPatternInfo(test);
                float dA = ResultPoint.distance(info.getTopLeft(), info.getBottomLeft());
                float dC = ResultPoint.distance(info.getTopRight(), info.getBottomLeft());
                float dB = ResultPoint.distance(info.getTopLeft(), info.getTopRight());
                // Check the sizes
                float estimatedModuleCount = (dA + dB) / (p1.getEstimatedModuleSize() * 2.0f);
                if (estimatedModuleCount > MAX_MODULE_COUNT_PER_EDGE || estimatedModuleCount < MIN_MODULE_COUNT_PER_EDGE) {
                    continue;
                }
                // Calculate the difference of the edge lengths in percent
                float vABBC = Math.abs((dA - dB) / Math.min(dA, dB));
                if (vABBC >= 0.1f) {
                    continue;
                }
                // Calculate the diagonal length by assuming a 90° angle at topleft
                float dCpy = (float) Math.sqrt(dA * dA + dB * dB);
                // Compare to the real distance in %
                float vPyC = Math.abs((dC - dCpy) / Math.min(dC, dCpy));
                if (vPyC >= 0.1f) {
                    continue;
                }
                // All tests passed!
                results.add(test);
            }
        // end iterate p3
        }
    // end iterate p2
    }
    if (!results.isEmpty()) {
        return results.toArray(new FinderPattern[results.size()][]);
    }
    // Nothing found!
    throw NotFoundException.getNotFoundInstance();
}

Example 8 with FinderPattern

use of com.google.zxing.qrcode.detector.FinderPattern in project android-zxing by PearceXu.

the class MultiFinderPatternFinder method findMulti.

public FinderPatternInfo[] findMulti(Map<DecodeHintType, ?> hints) throws NotFoundException {
    boolean tryHarder = hints != null && hints.containsKey(DecodeHintType.TRY_HARDER);
    boolean pureBarcode = hints != null && hints.containsKey(DecodeHintType.PURE_BARCODE);
    BitMatrix image = getImage();
    int maxI = image.getHeight();
    int maxJ = image.getWidth();
    // We are looking for black/white/black/white/black modules in
    // 1:1:3:1:1 ratio; this tracks the number of such modules seen so far
    // Let's assume that the maximum version QR Code we support takes up 1/4 the height of the
    // image, and then account for the center being 3 modules in size. This gives the smallest
    // number of pixels the center could be, so skip this often. When trying harder, look for all
    // QR versions regardless of how dense they are.
    int iSkip = (int) (maxI / (MAX_MODULES * 4.0f) * 3);
    if (iSkip < MIN_SKIP || tryHarder) {
        iSkip = MIN_SKIP;
    }
    int[] stateCount = new int[5];
    for (int i = iSkip - 1; i < maxI; i += iSkip) {
        // Get a row of black/white values
        stateCount[0] = 0;
        stateCount[1] = 0;
        stateCount[2] = 0;
        stateCount[3] = 0;
        stateCount[4] = 0;
        int currentState = 0;
        for (int j = 0; j < maxJ; j++) {
            if (image.get(j, i)) {
                // Black pixel
                if ((currentState & 1) == 1) {
                    // Counting white pixels
                    currentState++;
                }
                stateCount[currentState]++;
            } else {
                // White pixel
                if ((currentState & 1) == 0) {
                    // Counting black pixels
                    if (currentState == 4) {
                        // A winner?
                        if (foundPatternCross(stateCount) && handlePossibleCenter(stateCount, i, j, pureBarcode)) {
                            // Yes
                            // Clear state to start looking again
                            currentState = 0;
                            stateCount[0] = 0;
                            stateCount[1] = 0;
                            stateCount[2] = 0;
                            stateCount[3] = 0;
                            stateCount[4] = 0;
                        } else {
                            // No, shift counts back by two
                            stateCount[0] = stateCount[2];
                            stateCount[1] = stateCount[3];
                            stateCount[2] = stateCount[4];
                            stateCount[3] = 1;
                            stateCount[4] = 0;
                            currentState = 3;
                        }
                    } else {
                        stateCount[++currentState]++;
                    }
                } else {
                    // Counting white pixels
                    stateCount[currentState]++;
                }
            }
        }
        if (foundPatternCross(stateCount)) {
            handlePossibleCenter(stateCount, i, maxJ, pureBarcode);
        }
    // end if foundPatternCross
    }
    // for i=iSkip-1 ...
    FinderPattern[][] patternInfo = selectMutipleBestPatterns();
    List<FinderPatternInfo> result = new ArrayList<>();
    for (FinderPattern[] pattern : patternInfo) {
        ResultPoint.orderBestPatterns(pattern);
        result.add(new FinderPatternInfo(pattern));
    }
    if (result.isEmpty()) {
        return EMPTY_RESULT_ARRAY;
    } else {
        return result.toArray(new FinderPatternInfo[result.size()]);
    }
}