mirror of
https://github.com/status-im/qzxing.git
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564 lines
20 KiB
C++
564 lines
20 KiB
C++
// -*- mode:c++; tab-width:2; indent-tabs-mode:nil; c-basic-offset:2 -*-
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/*
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* Copyright 2010, 2012 ZXing authors All rights reserved.
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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#include <stdint.h>
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#include <bigint/BigIntegerUtils.hh>
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#include <zxing/FormatException.h>
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#include <zxing/pdf417/decoder/DecodedBitStreamParser.h>
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#include <zxing/common/DecoderResult.h>
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using std::string;
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using zxing::pdf417::DecodedBitStreamParser;
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using zxing::ArrayRef;
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using zxing::Ref;
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using zxing::DecoderResult;
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using zxing::String;
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const int DecodedBitStreamParser::TEXT_COMPACTION_MODE_LATCH = 900;
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const int DecodedBitStreamParser::BYTE_COMPACTION_MODE_LATCH = 901;
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const int DecodedBitStreamParser::NUMERIC_COMPACTION_MODE_LATCH = 902;
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const int DecodedBitStreamParser::BYTE_COMPACTION_MODE_LATCH_6 = 924;
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const int DecodedBitStreamParser::BEGIN_MACRO_PDF417_CONTROL_BLOCK = 928;
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const int DecodedBitStreamParser::BEGIN_MACRO_PDF417_OPTIONAL_FIELD = 923;
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const int DecodedBitStreamParser::MACRO_PDF417_TERMINATOR = 922;
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const int DecodedBitStreamParser::MODE_SHIFT_TO_BYTE_COMPACTION_MODE = 913;
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const int DecodedBitStreamParser::MAX_NUMERIC_CODEWORDS = 15;
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const int DecodedBitStreamParser::PL = 25;
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const int DecodedBitStreamParser::LL = 27;
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const int DecodedBitStreamParser::AS = 27;
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const int DecodedBitStreamParser::ML = 28;
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const int DecodedBitStreamParser::AL = 28;
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const int DecodedBitStreamParser::PS = 29;
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const int DecodedBitStreamParser::PAL = 29;
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const int DecodedBitStreamParser::EXP900_SIZE = 16;
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const char DecodedBitStreamParser::PUNCT_CHARS[] = {
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';', '<', '>', '@', '[', '\\', '}', '_', '`', '~', '!',
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'\r', '\t', ',', ':', '\n', '-', '.', '$', '/', '"', '|', '*',
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'(', ')', '?', '{', '}', '\''};
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const char DecodedBitStreamParser::MIXED_CHARS[] = {
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'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '&',
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'\r', '\t', ',', ':', '#', '-', '.', '$', '/', '+', '%', '*',
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'=', '^'};
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ArrayRef<BigInteger> DecodedBitStreamParser::initEXP900() {
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ArrayRef<BigInteger> EXP900 (16);
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EXP900[0] = BigInteger(1);
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BigInteger nineHundred (900);
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EXP900[1] = nineHundred;
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for (int i = 2; i < EXP900->size(); i++) {
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EXP900[i] = EXP900[i - 1] * nineHundred;
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}
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return EXP900;
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}
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ArrayRef<BigInteger> DecodedBitStreamParser::EXP900 = initEXP900();
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DecodedBitStreamParser::DecodedBitStreamParser(){}
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/**
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* PDF417 main decoder.
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**/
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Ref<DecoderResult> DecodedBitStreamParser::decode(ArrayRef<int> codewords)
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{
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Ref<String> result (new String(100));
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// Get compaction mode
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int codeIndex = 1;
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int code = codewords[codeIndex++];
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while (codeIndex < codewords[0]) {
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switch (code) {
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case TEXT_COMPACTION_MODE_LATCH:
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codeIndex = textCompaction(codewords, codeIndex, result);
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break;
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case BYTE_COMPACTION_MODE_LATCH:
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codeIndex = byteCompaction(code, codewords, codeIndex, result);
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break;
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case NUMERIC_COMPACTION_MODE_LATCH:
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codeIndex = numericCompaction(codewords, codeIndex, result);
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break;
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case MODE_SHIFT_TO_BYTE_COMPACTION_MODE:
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codeIndex = byteCompaction(code, codewords, codeIndex, result);
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break;
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case BYTE_COMPACTION_MODE_LATCH_6:
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codeIndex = byteCompaction(code, codewords, codeIndex, result);
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break;
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default:
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// Default to text compaction. During testing numerous barcodes
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// appeared to be missing the starting mode. In these cases defaulting
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// to text compaction seems to work.
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codeIndex--;
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codeIndex = textCompaction(codewords, codeIndex, result);
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break;
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}
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if (codeIndex < codewords->size()) {
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code = codewords[codeIndex++];
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} else {
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throw FormatException();
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}
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}
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return Ref<DecoderResult>(new DecoderResult(ArrayRef<char>(), result));
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}
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/**
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* Text Compaction mode (see 5.4.1.5) permits all printable ASCII characters to be
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* encoded, i.e. values 32 - 126 inclusive in accordance with ISO/IEC 646 (IRV), as
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* well as selected control characters.
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*
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* @param codewords The array of codewords (data + error)
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* @param codeIndex The current index into the codeword array.
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* @param result The decoded data is appended to the result.
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* @return The next index into the codeword array.
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*/
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int DecodedBitStreamParser::textCompaction(ArrayRef<int> codewords,
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int codeIndex,
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Ref<String> result) {
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// 2 character per codeword
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ArrayRef<int> textCompactionData (codewords[0] << 1);
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// Used to hold the byte compaction value if there is a mode shift
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ArrayRef<int> byteCompactionData (codewords[0] << 1);
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int index = 0;
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bool end = false;
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while ((codeIndex < codewords[0]) && !end) {
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int code = codewords[codeIndex++];
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if (code < TEXT_COMPACTION_MODE_LATCH) {
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textCompactionData[index] = code / 30;
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textCompactionData[index + 1] = code % 30;
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index += 2;
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} else {
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switch (code) {
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case TEXT_COMPACTION_MODE_LATCH:
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textCompactionData[index++] = TEXT_COMPACTION_MODE_LATCH;
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break;
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case BYTE_COMPACTION_MODE_LATCH:
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codeIndex--;
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end = true;
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break;
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case NUMERIC_COMPACTION_MODE_LATCH:
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codeIndex--;
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end = true;
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break;
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case MODE_SHIFT_TO_BYTE_COMPACTION_MODE:
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// The Mode Shift codeword 913 shall cause a temporary
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// switch from Text Compaction mode to Byte Compaction mode.
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// This switch shall be in effect for only the next codeword,
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// after which the mode shall revert to the prevailing sub-mode
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// of the Text Compaction mode. Codeword 913 is only available
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// in Text Compaction mode; its use is described in 5.4.2.4.
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textCompactionData[index] = MODE_SHIFT_TO_BYTE_COMPACTION_MODE;
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code = codewords[codeIndex++];
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byteCompactionData[index] = code; //Integer.toHexString(code);
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index++;
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break;
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case BYTE_COMPACTION_MODE_LATCH_6:
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codeIndex--;
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end = true;
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break;
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}
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}
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}
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decodeTextCompaction(textCompactionData, byteCompactionData, index, result);
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return codeIndex;
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}
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/**
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* The Text Compaction mode includes all the printable ASCII characters
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* (i.e. values from 32 to 126) and three ASCII control characters: HT or tab
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* (ASCII value 9), LF or line feed (ASCII value 10), and CR or carriage
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* return (ASCII value 13). The Text Compaction mode also includes various latch
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* and shift characters which are used exclusively within the mode. The Text
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* Compaction mode encodes up to 2 characters per codeword. The compaction rules
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* for converting data into PDF417 codewords are defined in 5.4.2.2. The sub-mode
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* switches are defined in 5.4.2.3.
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*
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* @param textCompactionData The text compaction data.
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* @param byteCompactionData The byte compaction data if there
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* was a mode shift.
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* @param length The size of the text compaction and byte compaction data.
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* @param result The decoded data is appended to the result.
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*/
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void DecodedBitStreamParser::decodeTextCompaction(ArrayRef<int> textCompactionData,
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ArrayRef<int> byteCompactionData,
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int length,
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Ref<String> result)
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{
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// Beginning from an initial state of the Alpha sub-mode
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// The default compaction mode for PDF417 in effect at the start of each symbol shall always be Text
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// Compaction mode Alpha sub-mode (uppercase alphabetic). A latch codeword from another mode to the Text
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// Compaction mode shall always switch to the Text Compaction Alpha sub-mode.
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Mode subMode = ALPHA;
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Mode priorToShiftMode = ALPHA;
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int i = 0;
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while (i < length) {
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int subModeCh = textCompactionData[i];
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char ch = 0;
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switch (subMode) {
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case ALPHA:
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// Alpha (uppercase alphabetic)
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if (subModeCh < 26) {
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// Upper case Alpha Character
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ch = (char) ('A' + subModeCh);
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} else {
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if (subModeCh == 26) {
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ch = ' ';
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} else if (subModeCh == LL) {
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subMode = LOWER;
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} else if (subModeCh == ML) {
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subMode = MIXED;
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} else if (subModeCh == PS) {
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// Shift to punctuation
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priorToShiftMode = subMode;
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subMode = PUNCT_SHIFT;
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} else if (subModeCh == MODE_SHIFT_TO_BYTE_COMPACTION_MODE) {
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result->append((char) byteCompactionData[i]);
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} else if (subModeCh == TEXT_COMPACTION_MODE_LATCH) {
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subMode = ALPHA;
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}
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}
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break;
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case LOWER:
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// Lower (lowercase alphabetic)
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if (subModeCh < 26) {
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ch = (char) ('a' + subModeCh);
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} else {
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if (subModeCh == 26) {
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ch = ' ';
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} else if (subModeCh == AS) {
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// Shift to alpha
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priorToShiftMode = subMode;
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subMode = ALPHA_SHIFT;
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} else if (subModeCh == ML) {
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subMode = MIXED;
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} else if (subModeCh == PS) {
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// Shift to punctuation
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priorToShiftMode = subMode;
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subMode = PUNCT_SHIFT;
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} else if (subModeCh == MODE_SHIFT_TO_BYTE_COMPACTION_MODE) {
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result->append((char) byteCompactionData[i]);
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} else if (subModeCh == TEXT_COMPACTION_MODE_LATCH) {
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subMode = ALPHA;
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}
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}
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break;
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case MIXED:
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// Mixed (numeric and some punctuation)
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if (subModeCh < PL) {
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ch = MIXED_CHARS[subModeCh];
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} else {
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if (subModeCh == PL) {
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subMode = PUNCT;
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} else if (subModeCh == 26) {
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ch = ' ';
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} else if (subModeCh == LL) {
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subMode = LOWER;
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} else if (subModeCh == AL) {
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subMode = ALPHA;
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} else if (subModeCh == PS) {
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// Shift to punctuation
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priorToShiftMode = subMode;
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subMode = PUNCT_SHIFT;
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} else if (subModeCh == MODE_SHIFT_TO_BYTE_COMPACTION_MODE) {
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result->append((char) byteCompactionData[i]);
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} else if (subModeCh == TEXT_COMPACTION_MODE_LATCH) {
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subMode = ALPHA;
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}
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}
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break;
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case PUNCT:
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// Punctuation
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if (subModeCh < PAL) {
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ch = PUNCT_CHARS[subModeCh];
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} else {
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if (subModeCh == PAL) {
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subMode = ALPHA;
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} else if (subModeCh == MODE_SHIFT_TO_BYTE_COMPACTION_MODE) {
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result->append((char) byteCompactionData[i]);
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} else if (subModeCh == TEXT_COMPACTION_MODE_LATCH) {
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subMode = ALPHA;
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}
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}
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break;
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case ALPHA_SHIFT:
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// Restore sub-mode
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subMode = priorToShiftMode;
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if (subModeCh < 26) {
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ch = (char) ('A' + subModeCh);
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} else {
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if (subModeCh == 26) {
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ch = ' ';
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} else {
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if (subModeCh == 26) {
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ch = ' ';
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} else if (subModeCh == TEXT_COMPACTION_MODE_LATCH) {
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subMode = ALPHA;
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}
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}
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}
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break;
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case PUNCT_SHIFT:
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// Restore sub-mode
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subMode = priorToShiftMode;
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if (subModeCh < PAL) {
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ch = PUNCT_CHARS[subModeCh];
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} else {
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if (subModeCh == PAL) {
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subMode = ALPHA;
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// 2012-11-27 added from recent java code:
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} else if (subModeCh == MODE_SHIFT_TO_BYTE_COMPACTION_MODE) {
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// PS before Shift-to-Byte is used as a padding character,
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// see 5.4.2.4 of the specification
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result->append((char) byteCompactionData[i]);
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} else if (subModeCh == TEXT_COMPACTION_MODE_LATCH) {
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subMode = ALPHA;
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}
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}
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break;
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}
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if (ch != 0) {
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// Append decoded character to result
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result->append(ch);
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}
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i++;
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}
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}
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/**
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* Byte Compaction mode (see 5.4.3) permits all 256 possible 8-bit byte values to be encoded.
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* This includes all ASCII characters value 0 to 127 inclusive and provides for international
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* character set support.
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*
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* @param mode The byte compaction mode i.e. 901 or 924
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* @param codewords The array of codewords (data + error)
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* @param codeIndex The current index into the codeword array.
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* @param result The decoded data is appended to the result.
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* @return The next index into the codeword array.
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*/
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int DecodedBitStreamParser::byteCompaction(int mode,
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ArrayRef<int> codewords,
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int codeIndex, Ref<String> result) {
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if (mode == BYTE_COMPACTION_MODE_LATCH) {
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// Total number of Byte Compaction characters to be encoded
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// is not a multiple of 6
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int count = 0;
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int64_t value = 0;
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ArrayRef<char> decodedData = new Array<char>(6);
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ArrayRef<int> byteCompactedCodewords = new Array<int>(6);
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bool end = false;
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int nextCode = codewords[codeIndex++];
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while ((codeIndex < codewords[0]) && !end) {
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byteCompactedCodewords[count++] = nextCode;
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// Base 900
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value = 900 * value + nextCode;
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nextCode = codewords[codeIndex++];
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// perhaps it should be ok to check only nextCode >= TEXT_COMPACTION_MODE_LATCH
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if (nextCode == TEXT_COMPACTION_MODE_LATCH ||
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nextCode == BYTE_COMPACTION_MODE_LATCH ||
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nextCode == NUMERIC_COMPACTION_MODE_LATCH ||
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nextCode == BYTE_COMPACTION_MODE_LATCH_6 ||
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nextCode == BEGIN_MACRO_PDF417_CONTROL_BLOCK ||
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nextCode == BEGIN_MACRO_PDF417_OPTIONAL_FIELD ||
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nextCode == MACRO_PDF417_TERMINATOR)
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{
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end = true;
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}
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else
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{
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if ((count%5 == 0) && (count > 0))
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{
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// Decode every 5 codewords
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// Convert to Base 256
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for (int j = 0; j < 6; ++j)
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{
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decodedData[5 - j] = (char) (value%256);
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value >>= 8;
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}
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result->append(string(&(decodedData->values()[0]), decodedData->values().size()));
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count = 0;
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}
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}
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}
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// if the end of all codewords is reached the last codeword needs to be added
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if (codeIndex == codewords[0] && nextCode < TEXT_COMPACTION_MODE_LATCH)
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byteCompactedCodewords[count++] = nextCode;
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// If Byte Compaction mode is invoked with codeword 901,
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// the last group of codewords is interpreted directly
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// as one byte per codeword, without compaction.
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for (int i = 0; i < count; i++)
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{
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result->append((char)byteCompactedCodewords[i]);
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}
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} else if (mode == BYTE_COMPACTION_MODE_LATCH_6) {
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// Total number of Byte Compaction characters to be encoded
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// is an integer multiple of 6
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int count = 0;
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int64_t value = 0;
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bool end = false;
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while (codeIndex < codewords[0] && !end) {
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int code = codewords[codeIndex++];
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if (code < TEXT_COMPACTION_MODE_LATCH) {
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count++;
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// Base 900
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value = 900 * value + code;
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} else {
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if (code == TEXT_COMPACTION_MODE_LATCH ||
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code == BYTE_COMPACTION_MODE_LATCH ||
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code == NUMERIC_COMPACTION_MODE_LATCH ||
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code == BYTE_COMPACTION_MODE_LATCH_6 ||
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code == BEGIN_MACRO_PDF417_CONTROL_BLOCK ||
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code == BEGIN_MACRO_PDF417_OPTIONAL_FIELD ||
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code == MACRO_PDF417_TERMINATOR) {
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codeIndex--;
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end = true;
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}
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}
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if ((count % 5 == 0) && (count > 0)) {
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// Decode every 5 codewords
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// Convert to Base 256
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ArrayRef<char> decodedData = new Array<char>(6);
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for (int j = 0; j < 6; ++j) {
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decodedData[5 - j] = (char) (value & 0xFF);
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value >>= 8;
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}
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result->append(string(&decodedData[0],6));
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// 2012-11-27 hfn after recent java code/fix by srowen
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count = 0;
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}
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}
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}
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return codeIndex;
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}
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/**
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* Numeric Compaction mode (see 5.4.4) permits efficient encoding of numeric data strings.
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*
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* @param codewords The array of codewords (data + error)
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* @param codeIndex The current index into the codeword array.
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* @param result The decoded data is appended to the result.
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* @return The next index into the codeword array.
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*/
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int DecodedBitStreamParser::numericCompaction(ArrayRef<int> codewords,
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int codeIndex,
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Ref<String> result) {
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int count = 0;
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bool end = false;
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ArrayRef<int> numericCodewords = new Array<int>(MAX_NUMERIC_CODEWORDS);
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while (codeIndex < codewords[0] && !end) {
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int code = codewords[codeIndex++];
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if (codeIndex == codewords[0]) {
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end = true;
|
|
}
|
|
if (code < TEXT_COMPACTION_MODE_LATCH) {
|
|
numericCodewords[count] = code;
|
|
count++;
|
|
} else {
|
|
if (code == TEXT_COMPACTION_MODE_LATCH ||
|
|
code == BYTE_COMPACTION_MODE_LATCH ||
|
|
code == BYTE_COMPACTION_MODE_LATCH_6 ||
|
|
code == BEGIN_MACRO_PDF417_CONTROL_BLOCK ||
|
|
code == BEGIN_MACRO_PDF417_OPTIONAL_FIELD ||
|
|
code == MACRO_PDF417_TERMINATOR) {
|
|
codeIndex--;
|
|
end = true;
|
|
}
|
|
}
|
|
if (count % MAX_NUMERIC_CODEWORDS == 0 ||
|
|
code == NUMERIC_COMPACTION_MODE_LATCH ||
|
|
end) {
|
|
// Re-invoking Numeric Compaction mode (by using codeword 902
|
|
// while in Numeric Compaction mode) serves to terminate the
|
|
// current Numeric Compaction mode grouping as described in 5.4.4.2,
|
|
// and then to start a new one grouping.
|
|
Ref<String> s = decodeBase900toBase10(numericCodewords, count);
|
|
result->append(s->getText());
|
|
count = 0;
|
|
}
|
|
}
|
|
return codeIndex;
|
|
}
|
|
|
|
/**
|
|
* Convert a list of Numeric Compacted codewords from Base 900 to Base 10.
|
|
*
|
|
* @param codewords The array of codewords
|
|
* @param count The number of codewords
|
|
* @return The decoded string representing the Numeric data.
|
|
*/
|
|
/*
|
|
EXAMPLE
|
|
Encode the fifteen digit numeric string 000213298174000
|
|
Prefix the numeric string with a 1 and set the initial value of
|
|
t = 1 000 213 298 174 000
|
|
Calculate codeword 0
|
|
d0 = 1 000 213 298 174 000 mod 900 = 200
|
|
|
|
t = 1 000 213 298 174 000 div 900 = 1 111 348 109 082
|
|
Calculate codeword 1
|
|
d1 = 1 111 348 109 082 mod 900 = 282
|
|
|
|
t = 1 111 348 109 082 div 900 = 1 234 831 232
|
|
Calculate codeword 2
|
|
d2 = 1 234 831 232 mod 900 = 632
|
|
|
|
t = 1 234 831 232 div 900 = 1 372 034
|
|
Calculate codeword 3
|
|
d3 = 1 372 034 mod 900 = 434
|
|
|
|
t = 1 372 034 div 900 = 1 524
|
|
Calculate codeword 4
|
|
d4 = 1 524 mod 900 = 624
|
|
|
|
t = 1 524 div 900 = 1
|
|
Calculate codeword 5
|
|
d5 = 1 mod 900 = 1
|
|
t = 1 div 900 = 0
|
|
Codeword sequence is: 1, 624, 434, 632, 282, 200
|
|
|
|
Decode the above codewords involves
|
|
1 x 900 power of 5 + 624 x 900 power of 4 + 434 x 900 power of 3 +
|
|
632 x 900 power of 2 + 282 x 900 power of 1 + 200 x 900 power of 0 = 1000213298174000
|
|
|
|
Remove leading 1 => Result is 000213298174000
|
|
*/
|
|
Ref<String> DecodedBitStreamParser::decodeBase900toBase10(ArrayRef<int> codewords, int count)
|
|
{
|
|
BigInteger result = BigInteger(0);
|
|
for (int i = 0; i < count; i++) {
|
|
result = result + (EXP900[count - i - 1] * BigInteger(codewords[i]));
|
|
}
|
|
string resultString = bigIntegerToString(result);
|
|
if (resultString[0] != '1') {
|
|
throw FormatException("DecodedBitStreamParser::decodeBase900toBase10: String does not begin with 1");
|
|
}
|
|
string resultString2;
|
|
resultString2.assign(resultString.begin()+1,resultString.end());
|
|
Ref<String> res (new String(resultString2));
|
|
return res;
|
|
}
|