diff options
Diffstat (limited to 'xfa/src/fxbarcode/common/reedsolomon/BC_ReedSolomonDecoder.cpp')
-rw-r--r-- | xfa/src/fxbarcode/common/reedsolomon/BC_ReedSolomonDecoder.cpp | 478 |
1 files changed, 239 insertions, 239 deletions
diff --git a/xfa/src/fxbarcode/common/reedsolomon/BC_ReedSolomonDecoder.cpp b/xfa/src/fxbarcode/common/reedsolomon/BC_ReedSolomonDecoder.cpp index 4ee87a4fa7..b053f2a784 100644 --- a/xfa/src/fxbarcode/common/reedsolomon/BC_ReedSolomonDecoder.cpp +++ b/xfa/src/fxbarcode/common/reedsolomon/BC_ReedSolomonDecoder.cpp @@ -1,239 +1,239 @@ -// 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 2007 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 "xfa/src/fxbarcode/barcode.h"
-#include "BC_ReedSolomonGF256.h"
-#include "BC_ReedSolomonGF256Poly.h"
-#include "BC_ReedSolomonDecoder.h"
-CBC_ReedSolomonDecoder::CBC_ReedSolomonDecoder(CBC_ReedSolomonGF256* field) {
- m_field = field;
-}
-CBC_ReedSolomonDecoder::~CBC_ReedSolomonDecoder() {}
-void CBC_ReedSolomonDecoder::Decode(CFX_Int32Array* received,
- int32_t twoS,
- int32_t& e) {
- CBC_ReedSolomonGF256Poly poly;
- poly.Init(m_field, received, e);
- BC_EXCEPTION_CHECK_ReturnVoid(e);
- CFX_Int32Array syndromeCoefficients;
- syndromeCoefficients.SetSize(twoS);
- FX_BOOL dataMatrix = FALSE;
- FX_BOOL noError = TRUE;
- for (int32_t i = 0; i < twoS; i++) {
- int32_t eval = poly.EvaluateAt(m_field->Exp(dataMatrix ? i + 1 : i));
- syndromeCoefficients[twoS - 1 - i] = eval;
- if (eval != 0) {
- noError = FALSE;
- }
- }
- if (noError) {
- return;
- }
- CBC_ReedSolomonGF256Poly syndrome;
- syndrome.Init(m_field, &syndromeCoefficients, e);
- BC_EXCEPTION_CHECK_ReturnVoid(e);
- CBC_ReedSolomonGF256Poly* rsg = m_field->BuildMonomial(twoS, 1, e);
- BC_EXCEPTION_CHECK_ReturnVoid(e);
- CBC_AutoPtr<CBC_ReedSolomonGF256Poly> temp(rsg);
- CFX_PtrArray* pa = RunEuclideanAlgorithm(temp.get(), &syndrome, twoS, e);
- BC_EXCEPTION_CHECK_ReturnVoid(e);
- CBC_AutoPtr<CFX_PtrArray> sigmaOmega(pa);
- CBC_AutoPtr<CBC_ReedSolomonGF256Poly> sigma(
- (CBC_ReedSolomonGF256Poly*)(*sigmaOmega)[0]);
- CBC_AutoPtr<CBC_ReedSolomonGF256Poly> omega(
- (CBC_ReedSolomonGF256Poly*)(*sigmaOmega)[1]);
- CFX_Int32Array* ia1 = FindErrorLocations(sigma.get(), e);
- BC_EXCEPTION_CHECK_ReturnVoid(e);
- CBC_AutoPtr<CFX_Int32Array> errorLocations(ia1);
- CFX_Int32Array* ia2 =
- FindErrorMagnitudes(omega.get(), errorLocations.get(), dataMatrix, e);
- BC_EXCEPTION_CHECK_ReturnVoid(e);
- CBC_AutoPtr<CFX_Int32Array> errorMagnitudes(ia2);
- for (int32_t k = 0; k < errorLocations->GetSize(); k++) {
- int32_t position =
- received->GetSize() - 1 - m_field->Log((*errorLocations)[k], e);
- BC_EXCEPTION_CHECK_ReturnVoid(e);
- if (position < 0) {
- e = BCExceptionBadErrorLocation;
- BC_EXCEPTION_CHECK_ReturnVoid(e);
- }
- (*received)[position] = CBC_ReedSolomonGF256::AddOrSubtract(
- (*received)[position], (*errorMagnitudes)[k]);
- }
-}
-CFX_PtrArray* CBC_ReedSolomonDecoder::RunEuclideanAlgorithm(
- CBC_ReedSolomonGF256Poly* a,
- CBC_ReedSolomonGF256Poly* b,
- int32_t R,
- int32_t& e) {
- if (a->GetDegree() < b->GetDegree()) {
- CBC_ReedSolomonGF256Poly* temp = a;
- a = b;
- b = temp;
- }
- CBC_ReedSolomonGF256Poly* rsg1 = a->Clone(e);
- BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
- CBC_AutoPtr<CBC_ReedSolomonGF256Poly> rLast(rsg1);
- CBC_ReedSolomonGF256Poly* rsg2 = b->Clone(e);
- BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
- CBC_AutoPtr<CBC_ReedSolomonGF256Poly> r(rsg2);
- CBC_ReedSolomonGF256Poly* rsg3 = m_field->GetOne()->Clone(e);
- BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
- CBC_AutoPtr<CBC_ReedSolomonGF256Poly> sLast(rsg3);
- CBC_ReedSolomonGF256Poly* rsg4 = m_field->GetZero()->Clone(e);
- BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
- CBC_AutoPtr<CBC_ReedSolomonGF256Poly> s(rsg4);
- CBC_ReedSolomonGF256Poly* rsg5 = m_field->GetZero()->Clone(e);
- BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
- CBC_AutoPtr<CBC_ReedSolomonGF256Poly> tLast(rsg5);
- CBC_ReedSolomonGF256Poly* rsg6 = m_field->GetOne()->Clone(e);
- BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
- CBC_AutoPtr<CBC_ReedSolomonGF256Poly> t(rsg6);
- while (r->GetDegree() >= R / 2) {
- CBC_AutoPtr<CBC_ReedSolomonGF256Poly> rLastLast = rLast;
- CBC_AutoPtr<CBC_ReedSolomonGF256Poly> sLastLast = sLast;
- CBC_AutoPtr<CBC_ReedSolomonGF256Poly> tLastlast = tLast;
- rLast = r;
- sLast = s;
- tLast = t;
- if (rLast->IsZero()) {
- e = BCExceptionR_I_1IsZero;
- BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
- }
- CBC_ReedSolomonGF256Poly* rsg7 = rLastLast->Clone(e);
- BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
- CBC_AutoPtr<CBC_ReedSolomonGF256Poly> rTemp(rsg7);
- r = rTemp;
- CBC_ReedSolomonGF256Poly* rsg8 = m_field->GetZero()->Clone(e);
- BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
- CBC_AutoPtr<CBC_ReedSolomonGF256Poly> q(rsg8);
- int32_t denominatorLeadingTerm = rLast->GetCoefficients(rLast->GetDegree());
- int32_t dltInverse = m_field->Inverse(denominatorLeadingTerm, e);
- BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
- while (r->GetDegree() >= rLast->GetDegree() && !(r->IsZero())) {
- int32_t degreeDiff = r->GetDegree() - rLast->GetDegree();
- int32_t scale =
- m_field->Multiply(r->GetCoefficients(r->GetDegree()), dltInverse);
- CBC_ReedSolomonGF256Poly* rsgp1 =
- m_field->BuildMonomial(degreeDiff, scale, e);
- BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
- CBC_AutoPtr<CBC_ReedSolomonGF256Poly> build(rsgp1);
- CBC_ReedSolomonGF256Poly* rsgp2 = q->AddOrSubtract(build.get(), e);
- BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
- CBC_AutoPtr<CBC_ReedSolomonGF256Poly> temp(rsgp2);
- q = temp;
- CBC_ReedSolomonGF256Poly* rsgp3 =
- rLast->MultiplyByMonomial(degreeDiff, scale, e);
- BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
- CBC_AutoPtr<CBC_ReedSolomonGF256Poly> multiply(rsgp3);
- CBC_ReedSolomonGF256Poly* rsgp4 = r->AddOrSubtract(multiply.get(), e);
- BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
- CBC_AutoPtr<CBC_ReedSolomonGF256Poly> temp3(rsgp4);
- r = temp3;
- }
- CBC_ReedSolomonGF256Poly* rsg9 = q->Multiply(sLast.get(), e);
- BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
- CBC_AutoPtr<CBC_ReedSolomonGF256Poly> temp1(rsg9);
- CBC_ReedSolomonGF256Poly* rsg10 = temp1->AddOrSubtract(sLastLast.get(), e);
- BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
- CBC_AutoPtr<CBC_ReedSolomonGF256Poly> temp2(rsg10);
- s = temp2;
- CBC_ReedSolomonGF256Poly* rsg11 = q->Multiply(tLast.get(), e);
- BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
- CBC_AutoPtr<CBC_ReedSolomonGF256Poly> temp5(rsg11);
- CBC_ReedSolomonGF256Poly* rsg12 = temp5->AddOrSubtract(tLastlast.get(), e);
- BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
- CBC_AutoPtr<CBC_ReedSolomonGF256Poly> temp6(rsg12);
- t = temp6;
- }
- int32_t sigmaTildeAtZero = t->GetCoefficients(0);
- if (sigmaTildeAtZero == 0) {
- e = BCExceptionIsZero;
- BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
- }
- int32_t inverse = m_field->Inverse(sigmaTildeAtZero, e);
- BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
- CBC_ReedSolomonGF256Poly* rsg13 = t->Multiply(inverse, e);
- BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
- CBC_AutoPtr<CBC_ReedSolomonGF256Poly> sigma(rsg13);
- CBC_ReedSolomonGF256Poly* rsg14 = r->Multiply(inverse, e);
- BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
- CBC_AutoPtr<CBC_ReedSolomonGF256Poly> omega(rsg14);
- CFX_PtrArray* temp = new CFX_PtrArray;
- temp->Add(sigma.release());
- temp->Add(omega.release());
- return temp;
-}
-CFX_Int32Array* CBC_ReedSolomonDecoder::FindErrorLocations(
- CBC_ReedSolomonGF256Poly* errorLocator,
- int32_t& e) {
- int32_t numErrors = errorLocator->GetDegree();
- if (numErrors == 1) {
- CBC_AutoPtr<CFX_Int32Array> temp(new CFX_Int32Array);
- temp->Add(errorLocator->GetCoefficients(1));
- return temp.release();
- }
- CFX_Int32Array* tempT = new CFX_Int32Array;
- tempT->SetSize(numErrors);
- CBC_AutoPtr<CFX_Int32Array> result(tempT);
- int32_t ie = 0;
- for (int32_t i = 1; i < 256 && ie < numErrors; i++) {
- if (errorLocator->EvaluateAt(i) == 0) {
- (*result)[ie] = m_field->Inverse(i, ie);
- BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
- ie++;
- }
- }
- if (ie != numErrors) {
- e = BCExceptionDegreeNotMatchRoots;
- BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
- }
- return result.release();
-}
-CFX_Int32Array* CBC_ReedSolomonDecoder::FindErrorMagnitudes(
- CBC_ReedSolomonGF256Poly* errorEvaluator,
- CFX_Int32Array* errorLocations,
- FX_BOOL dataMatrix,
- int32_t& e) {
- int32_t s = errorLocations->GetSize();
- CFX_Int32Array* temp = new CFX_Int32Array;
- temp->SetSize(s);
- CBC_AutoPtr<CFX_Int32Array> result(temp);
- for (int32_t i = 0; i < s; i++) {
- int32_t xiInverse = m_field->Inverse(errorLocations->operator[](i), e);
- BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
- int32_t denominator = 1;
- for (int32_t j = 0; j < s; j++) {
- if (i != j) {
- denominator = m_field->Multiply(
- denominator, CBC_ReedSolomonGF256::AddOrSubtract(
- 1, m_field->Multiply(errorLocations->operator[](j),
- xiInverse)));
- }
- }
- int32_t temp = m_field->Inverse(denominator, temp);
- BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
- (*result)[i] =
- m_field->Multiply(errorEvaluator->EvaluateAt(xiInverse), temp);
- }
- return result.release();
-}
+// 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 2007 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 "xfa/src/fxbarcode/barcode.h" +#include "BC_ReedSolomonGF256.h" +#include "BC_ReedSolomonGF256Poly.h" +#include "BC_ReedSolomonDecoder.h" +CBC_ReedSolomonDecoder::CBC_ReedSolomonDecoder(CBC_ReedSolomonGF256* field) { + m_field = field; +} +CBC_ReedSolomonDecoder::~CBC_ReedSolomonDecoder() {} +void CBC_ReedSolomonDecoder::Decode(CFX_Int32Array* received, + int32_t twoS, + int32_t& e) { + CBC_ReedSolomonGF256Poly poly; + poly.Init(m_field, received, e); + BC_EXCEPTION_CHECK_ReturnVoid(e); + CFX_Int32Array syndromeCoefficients; + syndromeCoefficients.SetSize(twoS); + FX_BOOL dataMatrix = FALSE; + FX_BOOL noError = TRUE; + for (int32_t i = 0; i < twoS; i++) { + int32_t eval = poly.EvaluateAt(m_field->Exp(dataMatrix ? i + 1 : i)); + syndromeCoefficients[twoS - 1 - i] = eval; + if (eval != 0) { + noError = FALSE; + } + } + if (noError) { + return; + } + CBC_ReedSolomonGF256Poly syndrome; + syndrome.Init(m_field, &syndromeCoefficients, e); + BC_EXCEPTION_CHECK_ReturnVoid(e); + CBC_ReedSolomonGF256Poly* rsg = m_field->BuildMonomial(twoS, 1, e); + BC_EXCEPTION_CHECK_ReturnVoid(e); + CBC_AutoPtr<CBC_ReedSolomonGF256Poly> temp(rsg); + CFX_PtrArray* pa = RunEuclideanAlgorithm(temp.get(), &syndrome, twoS, e); + BC_EXCEPTION_CHECK_ReturnVoid(e); + CBC_AutoPtr<CFX_PtrArray> sigmaOmega(pa); + CBC_AutoPtr<CBC_ReedSolomonGF256Poly> sigma( + (CBC_ReedSolomonGF256Poly*)(*sigmaOmega)[0]); + CBC_AutoPtr<CBC_ReedSolomonGF256Poly> omega( + (CBC_ReedSolomonGF256Poly*)(*sigmaOmega)[1]); + CFX_Int32Array* ia1 = FindErrorLocations(sigma.get(), e); + BC_EXCEPTION_CHECK_ReturnVoid(e); + CBC_AutoPtr<CFX_Int32Array> errorLocations(ia1); + CFX_Int32Array* ia2 = + FindErrorMagnitudes(omega.get(), errorLocations.get(), dataMatrix, e); + BC_EXCEPTION_CHECK_ReturnVoid(e); + CBC_AutoPtr<CFX_Int32Array> errorMagnitudes(ia2); + for (int32_t k = 0; k < errorLocations->GetSize(); k++) { + int32_t position = + received->GetSize() - 1 - m_field->Log((*errorLocations)[k], e); + BC_EXCEPTION_CHECK_ReturnVoid(e); + if (position < 0) { + e = BCExceptionBadErrorLocation; + BC_EXCEPTION_CHECK_ReturnVoid(e); + } + (*received)[position] = CBC_ReedSolomonGF256::AddOrSubtract( + (*received)[position], (*errorMagnitudes)[k]); + } +} +CFX_PtrArray* CBC_ReedSolomonDecoder::RunEuclideanAlgorithm( + CBC_ReedSolomonGF256Poly* a, + CBC_ReedSolomonGF256Poly* b, + int32_t R, + int32_t& e) { + if (a->GetDegree() < b->GetDegree()) { + CBC_ReedSolomonGF256Poly* temp = a; + a = b; + b = temp; + } + CBC_ReedSolomonGF256Poly* rsg1 = a->Clone(e); + BC_EXCEPTION_CHECK_ReturnValue(e, NULL); + CBC_AutoPtr<CBC_ReedSolomonGF256Poly> rLast(rsg1); + CBC_ReedSolomonGF256Poly* rsg2 = b->Clone(e); + BC_EXCEPTION_CHECK_ReturnValue(e, NULL); + CBC_AutoPtr<CBC_ReedSolomonGF256Poly> r(rsg2); + CBC_ReedSolomonGF256Poly* rsg3 = m_field->GetOne()->Clone(e); + BC_EXCEPTION_CHECK_ReturnValue(e, NULL); + CBC_AutoPtr<CBC_ReedSolomonGF256Poly> sLast(rsg3); + CBC_ReedSolomonGF256Poly* rsg4 = m_field->GetZero()->Clone(e); + BC_EXCEPTION_CHECK_ReturnValue(e, NULL); + CBC_AutoPtr<CBC_ReedSolomonGF256Poly> s(rsg4); + CBC_ReedSolomonGF256Poly* rsg5 = m_field->GetZero()->Clone(e); + BC_EXCEPTION_CHECK_ReturnValue(e, NULL); + CBC_AutoPtr<CBC_ReedSolomonGF256Poly> tLast(rsg5); + CBC_ReedSolomonGF256Poly* rsg6 = m_field->GetOne()->Clone(e); + BC_EXCEPTION_CHECK_ReturnValue(e, NULL); + CBC_AutoPtr<CBC_ReedSolomonGF256Poly> t(rsg6); + while (r->GetDegree() >= R / 2) { + CBC_AutoPtr<CBC_ReedSolomonGF256Poly> rLastLast = rLast; + CBC_AutoPtr<CBC_ReedSolomonGF256Poly> sLastLast = sLast; + CBC_AutoPtr<CBC_ReedSolomonGF256Poly> tLastlast = tLast; + rLast = r; + sLast = s; + tLast = t; + if (rLast->IsZero()) { + e = BCExceptionR_I_1IsZero; + BC_EXCEPTION_CHECK_ReturnValue(e, NULL); + } + CBC_ReedSolomonGF256Poly* rsg7 = rLastLast->Clone(e); + BC_EXCEPTION_CHECK_ReturnValue(e, NULL); + CBC_AutoPtr<CBC_ReedSolomonGF256Poly> rTemp(rsg7); + r = rTemp; + CBC_ReedSolomonGF256Poly* rsg8 = m_field->GetZero()->Clone(e); + BC_EXCEPTION_CHECK_ReturnValue(e, NULL); + CBC_AutoPtr<CBC_ReedSolomonGF256Poly> q(rsg8); + int32_t denominatorLeadingTerm = rLast->GetCoefficients(rLast->GetDegree()); + int32_t dltInverse = m_field->Inverse(denominatorLeadingTerm, e); + BC_EXCEPTION_CHECK_ReturnValue(e, NULL); + while (r->GetDegree() >= rLast->GetDegree() && !(r->IsZero())) { + int32_t degreeDiff = r->GetDegree() - rLast->GetDegree(); + int32_t scale = + m_field->Multiply(r->GetCoefficients(r->GetDegree()), dltInverse); + CBC_ReedSolomonGF256Poly* rsgp1 = + m_field->BuildMonomial(degreeDiff, scale, e); + BC_EXCEPTION_CHECK_ReturnValue(e, NULL); + CBC_AutoPtr<CBC_ReedSolomonGF256Poly> build(rsgp1); + CBC_ReedSolomonGF256Poly* rsgp2 = q->AddOrSubtract(build.get(), e); + BC_EXCEPTION_CHECK_ReturnValue(e, NULL); + CBC_AutoPtr<CBC_ReedSolomonGF256Poly> temp(rsgp2); + q = temp; + CBC_ReedSolomonGF256Poly* rsgp3 = + rLast->MultiplyByMonomial(degreeDiff, scale, e); + BC_EXCEPTION_CHECK_ReturnValue(e, NULL); + CBC_AutoPtr<CBC_ReedSolomonGF256Poly> multiply(rsgp3); + CBC_ReedSolomonGF256Poly* rsgp4 = r->AddOrSubtract(multiply.get(), e); + BC_EXCEPTION_CHECK_ReturnValue(e, NULL); + CBC_AutoPtr<CBC_ReedSolomonGF256Poly> temp3(rsgp4); + r = temp3; + } + CBC_ReedSolomonGF256Poly* rsg9 = q->Multiply(sLast.get(), e); + BC_EXCEPTION_CHECK_ReturnValue(e, NULL); + CBC_AutoPtr<CBC_ReedSolomonGF256Poly> temp1(rsg9); + CBC_ReedSolomonGF256Poly* rsg10 = temp1->AddOrSubtract(sLastLast.get(), e); + BC_EXCEPTION_CHECK_ReturnValue(e, NULL); + CBC_AutoPtr<CBC_ReedSolomonGF256Poly> temp2(rsg10); + s = temp2; + CBC_ReedSolomonGF256Poly* rsg11 = q->Multiply(tLast.get(), e); + BC_EXCEPTION_CHECK_ReturnValue(e, NULL); + CBC_AutoPtr<CBC_ReedSolomonGF256Poly> temp5(rsg11); + CBC_ReedSolomonGF256Poly* rsg12 = temp5->AddOrSubtract(tLastlast.get(), e); + BC_EXCEPTION_CHECK_ReturnValue(e, NULL); + CBC_AutoPtr<CBC_ReedSolomonGF256Poly> temp6(rsg12); + t = temp6; + } + int32_t sigmaTildeAtZero = t->GetCoefficients(0); + if (sigmaTildeAtZero == 0) { + e = BCExceptionIsZero; + BC_EXCEPTION_CHECK_ReturnValue(e, NULL); + } + int32_t inverse = m_field->Inverse(sigmaTildeAtZero, e); + BC_EXCEPTION_CHECK_ReturnValue(e, NULL); + CBC_ReedSolomonGF256Poly* rsg13 = t->Multiply(inverse, e); + BC_EXCEPTION_CHECK_ReturnValue(e, NULL); + CBC_AutoPtr<CBC_ReedSolomonGF256Poly> sigma(rsg13); + CBC_ReedSolomonGF256Poly* rsg14 = r->Multiply(inverse, e); + BC_EXCEPTION_CHECK_ReturnValue(e, NULL); + CBC_AutoPtr<CBC_ReedSolomonGF256Poly> omega(rsg14); + CFX_PtrArray* temp = new CFX_PtrArray; + temp->Add(sigma.release()); + temp->Add(omega.release()); + return temp; +} +CFX_Int32Array* CBC_ReedSolomonDecoder::FindErrorLocations( + CBC_ReedSolomonGF256Poly* errorLocator, + int32_t& e) { + int32_t numErrors = errorLocator->GetDegree(); + if (numErrors == 1) { + CBC_AutoPtr<CFX_Int32Array> temp(new CFX_Int32Array); + temp->Add(errorLocator->GetCoefficients(1)); + return temp.release(); + } + CFX_Int32Array* tempT = new CFX_Int32Array; + tempT->SetSize(numErrors); + CBC_AutoPtr<CFX_Int32Array> result(tempT); + int32_t ie = 0; + for (int32_t i = 1; i < 256 && ie < numErrors; i++) { + if (errorLocator->EvaluateAt(i) == 0) { + (*result)[ie] = m_field->Inverse(i, ie); + BC_EXCEPTION_CHECK_ReturnValue(e, NULL); + ie++; + } + } + if (ie != numErrors) { + e = BCExceptionDegreeNotMatchRoots; + BC_EXCEPTION_CHECK_ReturnValue(e, NULL); + } + return result.release(); +} +CFX_Int32Array* CBC_ReedSolomonDecoder::FindErrorMagnitudes( + CBC_ReedSolomonGF256Poly* errorEvaluator, + CFX_Int32Array* errorLocations, + FX_BOOL dataMatrix, + int32_t& e) { + int32_t s = errorLocations->GetSize(); + CFX_Int32Array* temp = new CFX_Int32Array; + temp->SetSize(s); + CBC_AutoPtr<CFX_Int32Array> result(temp); + for (int32_t i = 0; i < s; i++) { + int32_t xiInverse = m_field->Inverse(errorLocations->operator[](i), e); + BC_EXCEPTION_CHECK_ReturnValue(e, NULL); + int32_t denominator = 1; + for (int32_t j = 0; j < s; j++) { + if (i != j) { + denominator = m_field->Multiply( + denominator, CBC_ReedSolomonGF256::AddOrSubtract( + 1, m_field->Multiply(errorLocations->operator[](j), + xiInverse))); + } + } + int32_t temp = m_field->Inverse(denominator, temp); + BC_EXCEPTION_CHECK_ReturnValue(e, NULL); + (*result)[i] = + m_field->Multiply(errorEvaluator->EvaluateAt(xiInverse), temp); + } + return result.release(); +} |