1 // Copyright 2017 The PDFium Authors 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com 6 7 #include "core/fpdfapi/page/cpdf_expintfunc.h" 8 9 #include <math.h> 10 11 #include "core/fpdfapi/parser/cpdf_array.h" 12 #include "core/fpdfapi/parser/cpdf_dictionary.h" 13 #include "core/fpdfapi/parser/cpdf_number.h" 14 #include "core/fxcrt/data_vector.h" 15 #include "core/fxcrt/fx_2d_size.h" 16 #include "core/fxcrt/fx_safe_types.h" 17 #include "core/fxcrt/stl_util.h" 18 CPDF_ExpIntFunc()19CPDF_ExpIntFunc::CPDF_ExpIntFunc() 20 : CPDF_Function(Type::kType2ExponentialInterpolation) {} 21 22 CPDF_ExpIntFunc::~CPDF_ExpIntFunc() = default; 23 v_Init(const CPDF_Object * pObj,VisitedSet * pVisited)24bool CPDF_ExpIntFunc::v_Init(const CPDF_Object* pObj, VisitedSet* pVisited) { 25 CHECK(pObj->IsDictionary() || pObj->IsStream()); 26 RetainPtr<const CPDF_Dictionary> pDict = pObj->GetDict(); 27 RetainPtr<const CPDF_Number> pExponent = pDict->GetNumberFor("N"); 28 if (!pExponent) 29 return false; 30 31 m_Exponent = pExponent->GetNumber(); 32 33 RetainPtr<const CPDF_Array> pArray0 = pDict->GetArrayFor("C0"); 34 if (pArray0 && m_nOutputs == 0) 35 m_nOutputs = fxcrt::CollectionSize<uint32_t>(*pArray0); 36 if (m_nOutputs == 0) 37 m_nOutputs = 1; 38 39 RetainPtr<const CPDF_Array> pArray1 = pDict->GetArrayFor("C1"); 40 m_BeginValues = DataVector<float>(Fx2DSizeOrDie(m_nOutputs, 2)); 41 m_EndValues = DataVector<float>(m_BeginValues.size()); 42 for (uint32_t i = 0; i < m_nOutputs; i++) { 43 m_BeginValues[i] = pArray0 ? pArray0->GetFloatAt(i) : 0.0f; 44 m_EndValues[i] = pArray1 ? pArray1->GetFloatAt(i) : 1.0f; 45 } 46 47 FX_SAFE_UINT32 nOutputs = m_nOutputs; 48 nOutputs *= m_nInputs; 49 if (!nOutputs.IsValid()) 50 return false; 51 52 m_nOrigOutputs = m_nOutputs; 53 m_nOutputs = nOutputs.ValueOrDie(); 54 return true; 55 } 56 v_Call(pdfium::span<const float> inputs,pdfium::span<float> results) const57bool CPDF_ExpIntFunc::v_Call(pdfium::span<const float> inputs, 58 pdfium::span<float> results) const { 59 for (uint32_t i = 0; i < m_nInputs; i++) { 60 for (uint32_t j = 0; j < m_nOrigOutputs; j++) { 61 results[i * m_nOrigOutputs + j] = 62 m_BeginValues[j] + 63 powf(inputs[i], m_Exponent) * (m_EndValues[j] - m_BeginValues[j]); 64 } 65 } 66 return true; 67 } 68