// Copyright 2014 PDFium Authors. All rights reserved. | |
// Use of this source code is governed by a BSD-style license that can be | |
// found in the LICENSE file. | |
// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com | |
// Original code is licensed as follows: | |
/* | |
* 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. | |
*/ | |
#include "../barcode.h" | |
#include "BC_PDF417Common.h" | |
#include "BC_PDF417CodewordDecoder.h" | |
#define SYMBOL_TABLE_Length 2787 | |
#define Float_MAX_VALUE 2147483647 | |
FX_FLOAT CBC_PDF417CodewordDecoder::RATIOS_TABLE[2787][8] = {0}; | |
CBC_PDF417CodewordDecoder::CBC_PDF417CodewordDecoder() | |
{ | |
} | |
CBC_PDF417CodewordDecoder::~CBC_PDF417CodewordDecoder() | |
{ | |
} | |
void CBC_PDF417CodewordDecoder::Initialize() | |
{ | |
for (FX_INT32 i = 0; i < SYMBOL_TABLE_Length; i++) { | |
FX_INT32 currentSymbol = CBC_PDF417Common::SYMBOL_TABLE[i]; | |
FX_INT32 currentBit = currentSymbol & 0x1; | |
for (FX_INT32 j = 0; j < CBC_PDF417Common::BARS_IN_MODULE; j++) { | |
FX_FLOAT size = 0.0f; | |
while ((currentSymbol & 0x1) == currentBit) { | |
size += 1.0f; | |
currentSymbol >>= 1; | |
} | |
currentBit = currentSymbol & 0x1; | |
RATIOS_TABLE[i][CBC_PDF417Common::BARS_IN_MODULE - j - 1] = size / CBC_PDF417Common::MODULES_IN_CODEWORD; | |
} | |
} | |
} | |
void CBC_PDF417CodewordDecoder::Finalize() | |
{ | |
} | |
FX_INT32 CBC_PDF417CodewordDecoder::getDecodedValue(CFX_Int32Array& moduleBitCount) | |
{ | |
CFX_Int32Array* array = sampleBitCounts(moduleBitCount); | |
FX_INT32 decodedValue = getDecodedCodewordValue(*array); | |
delete array; | |
if (decodedValue != -1) { | |
return decodedValue; | |
} | |
return getClosestDecodedValue(moduleBitCount); | |
} | |
CFX_Int32Array* CBC_PDF417CodewordDecoder::sampleBitCounts(CFX_Int32Array& moduleBitCount) | |
{ | |
FX_FLOAT bitCountSum = (FX_FLOAT)CBC_PDF417Common::getBitCountSum(moduleBitCount); | |
CFX_Int32Array* bitCount = FX_NEW CFX_Int32Array(); | |
bitCount->SetSize(CBC_PDF417Common::BARS_IN_MODULE); | |
FX_INT32 bitCountIndex = 0; | |
FX_INT32 sumPreviousBits = 0; | |
for (FX_INT32 i = 0; i < CBC_PDF417Common::MODULES_IN_CODEWORD; i++) { | |
FX_FLOAT sampleIndex = bitCountSum / (2 * CBC_PDF417Common::MODULES_IN_CODEWORD) + (i * bitCountSum) / CBC_PDF417Common::MODULES_IN_CODEWORD; | |
if (sumPreviousBits + moduleBitCount.GetAt(bitCountIndex) <= sampleIndex) { | |
sumPreviousBits += moduleBitCount.GetAt(bitCountIndex); | |
bitCountIndex++; | |
} | |
bitCount->SetAt(bitCountIndex, bitCount->GetAt(bitCountIndex) + 1); | |
} | |
return bitCount; | |
} | |
FX_INT32 CBC_PDF417CodewordDecoder::getDecodedCodewordValue(CFX_Int32Array& moduleBitCount) | |
{ | |
FX_INT32 decodedValue = getBitValue(moduleBitCount); | |
return CBC_PDF417Common::getCodeword(decodedValue) == -1 ? -1 : decodedValue; | |
} | |
FX_INT32 CBC_PDF417CodewordDecoder::getBitValue(CFX_Int32Array& moduleBitCount) | |
{ | |
FX_INT64 result = 0; | |
for (FX_INT32 i = 0; i < moduleBitCount.GetSize(); i++) { | |
for (FX_INT32 bit = 0; bit < moduleBitCount.GetAt(i); bit++) { | |
result = (result << 1) | (i % 2 == 0 ? 1 : 0); | |
} | |
} | |
return (FX_INT32) result; | |
} | |
FX_INT32 CBC_PDF417CodewordDecoder::getClosestDecodedValue(CFX_Int32Array& moduleBitCount) | |
{ | |
FX_INT32 bitCountSum = CBC_PDF417Common::getBitCountSum(moduleBitCount); | |
CFX_FloatArray bitCountRatios; | |
bitCountRatios.SetSize(CBC_PDF417Common::BARS_IN_MODULE); | |
for (FX_INT32 i = 0; i < bitCountRatios.GetSize(); i++) { | |
bitCountRatios[i] = moduleBitCount.GetAt(i) / (FX_FLOAT) bitCountSum; | |
} | |
FX_FLOAT bestMatchError = (FX_FLOAT)Float_MAX_VALUE; | |
FX_INT32 bestMatch = -1; | |
for (FX_INT32 j = 0; j < SYMBOL_TABLE_Length; j++) { | |
FX_FLOAT error = 0.0f; | |
for (FX_INT32 k = 0; k < CBC_PDF417Common::BARS_IN_MODULE; k++) { | |
FX_FLOAT diff = RATIOS_TABLE[j][k] - bitCountRatios[k]; | |
error += diff * diff; | |
} | |
if (error < bestMatchError) { | |
bestMatchError = error; | |
bestMatch = CBC_PDF417Common::SYMBOL_TABLE[j]; | |
} | |
} | |
return bestMatch; | |
} |