zhusenlin/aistudio-wpf-diagram
1
0
Fork 0
mirror of https://gitee.com/akwkevin/aistudio.-wpf.-diagram synced 2026-04-11 11:46:37 +08:00
Code Issues Packages Projects Releases Wiki Activity

添加项目文件。

Browse Source
This commit is contained in:
akwkevin
2021-07-23 09:42:22 +08:00
commit f25a958797
2798 changed files with 352360 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

170
zxing.core/xx/pdf417/decoder/PDF417CodewordDecoder.cs Normal file
View File

@@ -0,0 +1,170 @@
/*
* 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.
*/
namespace ZXing.PDF417.Internal
{
/// <summary>
///
/// </summary>
/// <author>Guenther Grau</author>
/// <author>creatale GmbH (christoph.schulz@creatale.de)</author>
public static class PDF417CodewordDecoder
{
/// <summary>
/// The ratios table
/// </summary>
private static readonly float[][] RATIOS_TABLE; // = new float[PDF417Common.SYMBOL_TABLE.Length][PDF417Common.BARS_IN_MODULE];
/// <summary>
/// Initializes the <see cref="ZXing.PDF417.Internal.PDF417CodewordDecoder"/> class & Pre-computes the symbol ratio table.
/// </summary>
static PDF417CodewordDecoder()
{
// Jagged arrays in Java assign the memory automatically, but C# has no equivalent. (Jon Skeet says so!)
// http://stackoverflow.com/a/5313879/266252
RATIOS_TABLE = new float[PDF417Common.SYMBOL_TABLE.Length][];
for (int s = 0; s < RATIOS_TABLE.Length; s++)
{
RATIOS_TABLE[s] = new float[PDF417Common.BARS_IN_MODULE];
}
// Pre-computes the symbol ratio table.
for (int i = 0; i < PDF417Common.SYMBOL_TABLE.Length; i++)
{
int currentSymbol = PDF417Common.SYMBOL_TABLE[i];
int currentBit = currentSymbol & 0x1;
for (int j = 0; j < PDF417Common.BARS_IN_MODULE; j++)
{
float size = 0.0f;
while ((currentSymbol & 0x1) == currentBit)
{
size += 1.0f;
currentSymbol >>= 1;
}
currentBit = currentSymbol & 0x1;
RATIOS_TABLE[i][PDF417Common.BARS_IN_MODULE - j - 1] = size/PDF417Common.MODULES_IN_CODEWORD;
}
}
}
/// <summary>
/// Gets the decoded value.
/// </summary>
/// <returns>The decoded value.</returns>
/// <param name="moduleBitCount">Module bit count.</param>
public static int getDecodedValue(int[] moduleBitCount)
{
int decodedValue = getDecodedCodewordValue(sampleBitCounts(moduleBitCount));
if (decodedValue != PDF417Common.INVALID_CODEWORD)
{
return decodedValue;
}
return getClosestDecodedValue(moduleBitCount);
}
/// <summary>
/// Samples the bit counts.
/// </summary>
/// <returns>The bit counts.</returns>
/// <param name="moduleBitCount">Module bit count.</param>
private static int[] sampleBitCounts(int[] moduleBitCount)
{
float bitCountSum = PDF417Common.getBitCountSum(moduleBitCount);
int[] result = new int[PDF417Common.BARS_IN_MODULE];
int bitCountIndex = 0;
int sumPreviousBits = 0;
for (int i = 0; i < PDF417Common.MODULES_IN_CODEWORD; i++)
{
float sampleIndex =
bitCountSum/(2*PDF417Common.MODULES_IN_CODEWORD) +
(i*bitCountSum)/PDF417Common.MODULES_IN_CODEWORD;
if (sumPreviousBits + moduleBitCount[bitCountIndex] <= sampleIndex)
{
sumPreviousBits += moduleBitCount[bitCountIndex];
bitCountIndex++;
}
result[bitCountIndex]++;
}
return result;
}
/// <summary>
/// Gets the decoded codeword value.
/// </summary>
/// <returns>The decoded codeword value.</returns>
/// <param name="moduleBitCount">Module bit count.</param>
private static int getDecodedCodewordValue(int[] moduleBitCount)
{
int decodedValue = getBitValue(moduleBitCount);
return PDF417Common.getCodeword(decodedValue) == PDF417Common.INVALID_CODEWORD ? PDF417Common.INVALID_CODEWORD : decodedValue;
}
/// <summary>
/// Gets the bit value.
/// </summary>
/// <returns>The bit value.</returns>
/// <param name="moduleBitCount">Module bit count.</param>
private static int getBitValue(int[] moduleBitCount)
{
ulong result = 0;
for (ulong i = 0; i < (ulong) moduleBitCount.Length; i++)
{
for (int bit = 0; bit < moduleBitCount[i]; bit++)
{
result = (result << 1) | (i%2ul == 0ul ? 1ul : 0ul); // C# was warning about using the bit-wise 'OR' here with a mix of int/longs.
}
}
return (int) result;
}
/// <summary>
/// Gets the closest decoded value.
/// </summary>
/// <returns>The closest decoded value.</returns>
/// <param name="moduleBitCount">Module bit count.</param>
private static int getClosestDecodedValue(int[] moduleBitCount)
{
int bitCountSum = PDF417Common.getBitCountSum(moduleBitCount);
float[] bitCountRatios = new float[PDF417Common.BARS_IN_MODULE];
for (int i = 0; i < bitCountRatios.Length; i++)
{
bitCountRatios[i] = moduleBitCount[i]/(float) bitCountSum;
}
float bestMatchError = float.MaxValue;
int bestMatch = PDF417Common.INVALID_CODEWORD;
for (int j = 0; j < RATIOS_TABLE.Length; j++)
{
float error = 0.0f;
float[] ratioTableRow = RATIOS_TABLE[j];
for (int k = 0; k < PDF417Common.BARS_IN_MODULE; k++)
{
float diff = ratioTableRow[k] - bitCountRatios[k];
error += diff*diff;
if (error >= bestMatchError)
{
break;
}
}
if (error < bestMatchError)
{
bestMatchError = error;
bestMatch = PDF417Common.SYMBOL_TABLE[j];
}
}
return bestMatch;
}
}
}