78 lines
3.3 KiB
C++
78 lines
3.3 KiB
C++
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/**********************************************************************
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* File: mod128.cpp (Formerly dir128.c)
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* Description: Code to convert a DIR128 to an ICOORD.
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* Author: Ray Smith
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*
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* (C) Copyright 1991, Hewlett-Packard Ltd.
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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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** http://www.apache.org/licenses/LICENSE-2.0
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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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**********************************************************************/
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#include "mod128.h"
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namespace tesseract {
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static const int16_t idirtab[] = {
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1000, 0, 998, 49, 995, 98, 989, 146, 980, 195, 970, 242, 956, 290, 941,
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336, 923, 382, 903, 427, 881, 471, 857, 514, 831, 555, 803, 595, 773, 634,
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740, 671, 707, 707, 671, 740, 634, 773, 595, 803, 555, 831, 514, 857, 471,
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881, 427, 903, 382, 923, 336, 941, 290, 956, 242, 970, 195, 980, 146, 989,
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98, 995, 49, 998, 0, 1000, -49, 998, -98, 995, -146, 989, -195, 980, -242,
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970, -290, 956, -336, 941, -382, 923, -427, 903, -471, 881, -514, 857, -555, 831,
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-595, 803, -634, 773, -671, 740, -707, 707, -740, 671, -773, 634, -803, 595, -831,
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555, -857, 514, -881, 471, -903, 427, -923, 382, -941, 336, -956, 290, -970, 242,
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-980, 195, -989, 146, -995, 98, -998, 49, -1000, 0, -998, -49, -995, -98, -989,
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-146, -980, -195, -970, -242, -956, -290, -941, -336, -923, -382, -903, -427, -881, -471,
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-857, -514, -831, -555, -803, -595, -773, -634, -740, -671, -707, -707, -671, -740, -634,
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-773, -595, -803, -555, -831, -514, -857, -471, -881, -427, -903, -382, -923, -336, -941,
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-290, -956, -242, -970, -195, -980, -146, -989, -98, -995, -49, -998, 0, -1000, 49,
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-998, 98, -995, 146, -989, 195, -980, 242, -970, 290, -956, 336, -941, 382, -923,
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427, -903, 471, -881, 514, -857, 555, -831, 595, -803, 634, -773, 671, -740, 707,
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-707, 740, -671, 773, -634, 803, -595, 831, -555, 857, -514, 881, -471, 903, -427,
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923, -382, 941, -336, 956, -290, 970, -242, 980, -195, 989, -146, 995, -98, 998,
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-49};
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static const ICOORD *dirtab = reinterpret_cast<const ICOORD *>(idirtab);
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/**********************************************************************
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* DIR128::DIR128
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*
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* Quantize the direction of an FCOORD to make a DIR128.
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**********************************************************************/
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DIR128::DIR128( // from fcoord
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const FCOORD fc // vector to quantize
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) {
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int high, low, current; // binary search
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low = 0;
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if (fc.y() == 0) {
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if (fc.x() >= 0) {
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dir = 0;
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} else {
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dir = MODULUS / 2;
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}
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return;
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}
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high = MODULUS;
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do {
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current = (high + low) / 2;
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if (dirtab[current] * fc >= 0) {
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low = current;
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} else {
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high = current;
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}
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} while (high - low > 1);
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dir = low;
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}
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} // namespace tesseract
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