/*
* Copyright 2013 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.
*/
using System;
namespace ZXing.PDF417.Internal
{
/// <summary>
/// Represents a Column in the Detection Result
/// </summary>
/// <author>Guenther Grau</author>
public sealed class DetectionResultRowIndicatorColumn : DetectionResultColumn
{
/// <summary>
/// Gets or sets a value indicating whether this instance is the left indicator
/// </summary>
/// <value><c>true if this instance is left; otherwise, false.
public bool IsLeft { get; set; }
/// <summary>
/// Initializes a new instance of the <see cref="ZXing.PDF417.Internal.DetectionResultRowIndicatorColumn"/> class.
/// </summary>
/// <param name="box">Box.</param>
/// <param name="isLeft">If set to <c>true is left.
public DetectionResultRowIndicatorColumn(BoundingBox box, bool isLeft)
: base(box)
{
this.IsLeft = isLeft;
}
/// <summary>
/// Sets the Row Numbers as Inidicator Columns
/// </summary>
private void setRowNumbers()
{
foreach (var cw in Codewords)
{
if (cw != null)
{
cw.setRowNumberAsRowIndicatorColumn();
}
}
}
/// <summary>
/// TODO implement properly
/// TODO maybe we should add missing codewords to store the correct row number to make
/// finding row numbers for other columns easier
/// use row height count to make detection of invalid row numbers more reliable
/// </summary>
/// <returns>The indicator column row numbers.</returns>
/// <param name="metadata">Metadata.</param>
public void adjustCompleteIndicatorColumnRowNumbers(BarcodeMetadata metadata)
{
var codewords = Codewords;
setRowNumbers(); // Assign this as an indicator column
removeIncorrectCodewords(codewords, metadata);
ResultPoint top = IsLeft ? Box.TopLeft : Box.TopRight;
ResultPoint bottom = IsLeft ? Box.BottomLeft : Box.BottomRight;
int firstRow = imageRowToCodewordIndex((int) top.Y);
int lastRow = imageRowToCodewordIndex((int) bottom.Y);
// We need to be careful using the average row height.
// Barcode could be skewed so that we have smaller and taller rows
//float averageRowHeight = (lastRow - firstRow)/(float) metadata.RowCount;
// initialize loop
int barcodeRow = -1;
int maxRowHeight = 1;
int currentRowHeight = 0;
for (int codewordRow = firstRow; codewordRow < lastRow; codewordRow++)
{
var codeword = codewords[codewordRow];
if (codeword == null)
{
continue;
}
// float expectedRowNumber = (codewordsRow - firstRow) / averageRowHeight;
// if (Math.abs(codeword.getRowNumber() - expectedRowNumber) > 2) {
// SimpleLog.log(LEVEL.WARNING,
// "Removing codeword, rowNumberSkew too high, codeword[" + codewordsRow + "]: Expected Row: " +
// expectedRowNumber + ", RealRow: " + codeword.getRowNumber() + ", value: " + codeword.getValue());
// codewords[codewordsRow] = null;
// }
int rowDifference = codeword.RowNumber - barcodeRow;
// TODO improve handling with case where first row indicator doesn't start with 0
if (rowDifference == 0)
{
currentRowHeight++;
}
else if (rowDifference == 1)
{
maxRowHeight = Math.Max(maxRowHeight, currentRowHeight);
currentRowHeight = 1;
barcodeRow = codeword.RowNumber;
}
else if (rowDifference < 0 ||
codeword.RowNumber >= metadata.RowCount ||
rowDifference > codewordRow)
{
codewords[codewordRow] = null;
}
else
{
int checkedRows;
if (maxRowHeight > 2)
{
checkedRows = (maxRowHeight - 2)*rowDifference;
}
else
{
checkedRows = rowDifference;
}
bool closePreviousCodewordFound = checkedRows > codewordRow;
for (int i = 1; i <= checkedRows && !closePreviousCodewordFound; i++)
{
// there must be (height * rowDifference) number of codewords missing. For now we assume height = 1.
// This should hopefully get rid of most problems already.
closePreviousCodewordFound = codewords[codewordRow - i] != null;
}
if (closePreviousCodewordFound)
{
codewords[codewordRow] = null;
}
else
{
barcodeRow = codeword.RowNumber;
currentRowHeight = 1;
}
}
}
//return (int) (averageRowHeight + 0.5);
}
/// <summary>
/// Gets the row heights.
/// </summary>
/// <returns>The row heights.</returns>
public int[] getRowHeights()
{
BarcodeMetadata barcodeMetadata = getBarcodeMetadata();
if (barcodeMetadata == null)
{
return null;
}
adjustIncompleteIndicatorColumnRowNumbers(barcodeMetadata);
int[] result = new int[barcodeMetadata.RowCount];
foreach (var codeword in Codewords)
{
if (codeword != null)
{
int rowNumber = codeword.RowNumber;
if (rowNumber >= result.Length)
{
// We have more rows than the barcode metadata allows for, ignore them.
continue;
}
result[rowNumber]++;
} // else throw exception? (or return null)
}
return result;
}
/// <summary>
/// Adjusts the in omplete indicator column row numbers.
/// </summary>
/// <param name="metadata">Metadata.</param>
private void adjustIncompleteIndicatorColumnRowNumbers(BarcodeMetadata metadata)
{
// TODO maybe we should add missing codewords to store the correct row number to make
// finding row numbers for other columns easier
// use row height count to make detection of invalid row numbers more reliable
ResultPoint top = IsLeft ? Box.TopLeft : Box.TopRight;
ResultPoint bottom = IsLeft ? Box.BottomLeft : Box.BottomRight;
int firstRow = imageRowToCodewordIndex((int) top.Y);
int lastRow = imageRowToCodewordIndex((int) bottom.Y);
// We need to be careful using the average row height.
// Barcode could be skewed so that we have smaller and taller rows
//float averageRowHeight = (lastRow - firstRow)/(float) metadata.RowCount;
var codewords = Codewords;
// initialize loop
int barcodeRow = -1;
int maxRowHeight = 1;
int currentRowHeight = 0;
for (int codewordRow = firstRow; codewordRow < lastRow; codewordRow++)
{
var codeword = codewords[codewordRow];
if (codeword == null)
{
continue;
}
codeword.setRowNumberAsRowIndicatorColumn();
int rowDifference = codeword.RowNumber - barcodeRow;
// TODO improve handling with case where first row indicator doesn't start with 0
if (rowDifference == 0)
{
currentRowHeight++;
}
else if (rowDifference == 1)
{
maxRowHeight = Math.Max(maxRowHeight, currentRowHeight);
currentRowHeight = 1;
barcodeRow = codeword.RowNumber;
}
else if (codeword.RowNumber > metadata.RowCount)
{
Codewords[codewordRow] = null;
}
else
{
barcodeRow = codeword.RowNumber;
currentRowHeight = 1;
}
}
// return (int) (averageRowHeight + 0.5);
}
/// <summary>
/// Gets the barcode metadata.
/// </summary>
/// <returns>The barcode metadata.</returns>
public BarcodeMetadata getBarcodeMetadata()
{
var codewords = Codewords;
BarcodeValue barcodeColumnCount = new BarcodeValue();
BarcodeValue barcodeRowCountUpperPart = new BarcodeValue();
BarcodeValue barcodeRowCountLowerPart = new BarcodeValue();
BarcodeValue barcodeECLevel = new BarcodeValue();
foreach (Codeword codeword in codewords)
{
if (codeword == null)
{
continue;
}
codeword.setRowNumberAsRowIndicatorColumn();
int rowIndicatorValue = codeword.Value%30;
int codewordRowNumber = codeword.RowNumber;
if (!IsLeft)
{
codewordRowNumber += 2;
}
switch (codewordRowNumber%3)
{
case 0:
barcodeRowCountUpperPart.setValue(rowIndicatorValue*3 + 1);
break;
case 1:
barcodeECLevel.setValue(rowIndicatorValue/3);
barcodeRowCountLowerPart.setValue(rowIndicatorValue%3);
break;
case 2:
barcodeColumnCount.setValue(rowIndicatorValue + 1);
break;
}
}
// Maybe we should check if we have ambiguous values?
var barcodeColumnCountValues = barcodeColumnCount.getValue();
var barcodeRowCountUpperPartValues = barcodeRowCountUpperPart.getValue();
var barcodeRowCountLowerPartValues = barcodeRowCountLowerPart.getValue();
var barcodeECLevelValues = barcodeECLevel.getValue();
if ((barcodeColumnCountValues.Length == 0) ||
(barcodeRowCountUpperPartValues.Length == 0) ||
(barcodeRowCountLowerPartValues.Length == 0) ||
(barcodeECLevelValues.Length == 0) ||
barcodeColumnCountValues[0] < 1 ||
barcodeRowCountUpperPartValues[0] + barcodeRowCountLowerPartValues[0] < PDF417Common.MIN_ROWS_IN_BARCODE ||
barcodeRowCountUpperPartValues[0] + barcodeRowCountLowerPartValues[0] > PDF417Common.MAX_ROWS_IN_BARCODE)
{
return null;
}
var barcodeMetadata = new BarcodeMetadata(barcodeColumnCountValues[0],
barcodeRowCountUpperPartValues[0],
barcodeRowCountLowerPartValues[0],
barcodeECLevelValues[0]);
removeIncorrectCodewords(codewords, barcodeMetadata);
return barcodeMetadata;
}
/// <summary>
/// Prune the codewords which do not match the metadata
/// TODO Maybe we should keep the incorrect codewords for the start and end positions?
/// </summary>
/// <param name="codewords">Codewords.</param>
/// <param name="metadata">Metadata.</param>
private void removeIncorrectCodewords(Codeword[] codewords, BarcodeMetadata metadata)
{
for (int row = 0; row < codewords.Length; row++)
{
var codeword = codewords[row];
if (codeword == null)
continue;
int indicatorValue = codeword.Value%30;
int rowNumber = codeword.RowNumber;
// Row does not exist in the metadata
if (rowNumber >= metadata.RowCount) // different to java rowNumber > metadata.RowCount
{
codewords[row] = null; // remove this.
continue;
}
if (!IsLeft)
{
rowNumber += 2;
}
switch (rowNumber%3)
{
default:
case 0:
if (indicatorValue*3 + 1 != metadata.RowCountUpper)
{
codewords[row] = null;
}
break;
case 1:
if (indicatorValue%3 != metadata.RowCountLower ||
indicatorValue/3 != metadata.ErrorCorrectionLevel)
{
codewords[row] = null;
}
break;
case 2:
if (indicatorValue + 1 != metadata.ColumnCount)
{
codewords[row] = null;
}
break;
}
}
}
/// <summary>
/// Returns a <see cref="System.String"/> that represents the current <see cref="ZXing.PDF417.Internal.DetectionResultRowIndicatorColumn"/>.
/// </summary>
/// <returns>A <see cref="System.String"/> that represents the current .
public override string ToString()
{
return "Is Left: " + IsLeft + " \n" + base.ToString();
}
}
}
