| // Copyright 2017 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 |
| |
| #include "core/fpdfapi/page/cpdf_function.h" |
| |
| #include <vector> |
| |
| #include "core/fpdfapi/page/cpdf_expintfunc.h" |
| #include "core/fpdfapi/page/cpdf_psfunc.h" |
| #include "core/fpdfapi/page/cpdf_sampledfunc.h" |
| #include "core/fpdfapi/page/cpdf_stitchfunc.h" |
| #include "core/fpdfapi/parser/cpdf_array.h" |
| #include "core/fpdfapi/parser/cpdf_dictionary.h" |
| #include "core/fpdfapi/parser/cpdf_stream.h" |
| #include "core/fpdfapi/parser/fpdf_parser_utility.h" |
| #include "core/fxcrt/fx_safe_types.h" |
| #include "third_party/base/stl_util.h" |
| |
| namespace { |
| |
| CPDF_Function::Type IntegerToFunctionType(int iType) { |
| switch (iType) { |
| case 0: |
| case 2: |
| case 3: |
| case 4: |
| return static_cast<CPDF_Function::Type>(iType); |
| default: |
| return CPDF_Function::Type::kTypeInvalid; |
| } |
| } |
| |
| } // namespace |
| |
| // static |
| std::unique_ptr<CPDF_Function> CPDF_Function::Load( |
| const CPDF_Object* pFuncObj) { |
| std::set<const CPDF_Object*> visited; |
| return Load(pFuncObj, &visited); |
| } |
| |
| // static |
| std::unique_ptr<CPDF_Function> CPDF_Function::Load( |
| const CPDF_Object* pFuncObj, |
| std::set<const CPDF_Object*>* pVisited) { |
| if (!pFuncObj) |
| return nullptr; |
| |
| if (pdfium::Contains(*pVisited, pFuncObj)) |
| return nullptr; |
| pdfium::ScopedSetInsertion<const CPDF_Object*> insertion(pVisited, pFuncObj); |
| |
| int iType = -1; |
| if (const CPDF_Stream* pStream = pFuncObj->AsStream()) |
| iType = pStream->GetDict()->GetIntegerFor("FunctionType"); |
| else if (const CPDF_Dictionary* pDict = pFuncObj->AsDictionary()) |
| iType = pDict->GetIntegerFor("FunctionType"); |
| |
| std::unique_ptr<CPDF_Function> pFunc; |
| Type type = IntegerToFunctionType(iType); |
| if (type == Type::kType0Sampled) |
| pFunc = std::make_unique<CPDF_SampledFunc>(); |
| else if (type == Type::kType2ExponentialInterpolation) |
| pFunc = std::make_unique<CPDF_ExpIntFunc>(); |
| else if (type == Type::kType3Stitching) |
| pFunc = std::make_unique<CPDF_StitchFunc>(); |
| else if (type == Type::kType4PostScript) |
| pFunc = std::make_unique<CPDF_PSFunc>(); |
| |
| if (!pFunc || !pFunc->Init(pFuncObj, pVisited)) |
| return nullptr; |
| |
| return pFunc; |
| } |
| |
| CPDF_Function::CPDF_Function(Type type) : m_Type(type) {} |
| |
| CPDF_Function::~CPDF_Function() = default; |
| |
| bool CPDF_Function::Init(const CPDF_Object* pObj, |
| std::set<const CPDF_Object*>* pVisited) { |
| const CPDF_Stream* pStream = pObj->AsStream(); |
| const CPDF_Dictionary* pDict = |
| pStream ? pStream->GetDict() : pObj->AsDictionary(); |
| |
| const CPDF_Array* pDomains = pDict->GetArrayFor("Domain"); |
| if (!pDomains) |
| return false; |
| |
| m_nInputs = pDomains->size() / 2; |
| if (m_nInputs == 0) |
| return false; |
| |
| size_t nInputs = m_nInputs * 2; |
| m_Domains = ReadArrayElementsToVector(pDomains, nInputs); |
| |
| const CPDF_Array* pRanges = pDict->GetArrayFor("Range"); |
| m_nOutputs = pRanges ? pRanges->size() / 2 : 0; |
| |
| // Ranges are required for type 0 and type 4 functions. A non-zero |
| // |m_nOutputs| here implied Ranges meets the requirements. |
| bool bRangeRequired = |
| m_Type == Type::kType0Sampled || m_Type == Type::kType4PostScript; |
| if (bRangeRequired && m_nOutputs == 0) |
| return false; |
| |
| if (m_nOutputs > 0) { |
| size_t nOutputs = m_nOutputs * 2; |
| m_Ranges = ReadArrayElementsToVector(pRanges, nOutputs); |
| } |
| |
| uint32_t old_outputs = m_nOutputs; |
| if (!v_Init(pObj, pVisited)) |
| return false; |
| |
| if (!m_Ranges.empty() && m_nOutputs > old_outputs) { |
| FX_SAFE_SIZE_T nOutputs = m_nOutputs; |
| nOutputs *= 2; |
| m_Ranges.resize(nOutputs.ValueOrDie()); |
| } |
| return true; |
| } |
| |
| bool CPDF_Function::Call(const float* inputs, |
| uint32_t ninputs, |
| float* results, |
| int* nresults) const { |
| if (m_nInputs != ninputs) |
| return false; |
| |
| *nresults = m_nOutputs; |
| std::vector<float> clamped_inputs(m_nInputs); |
| for (uint32_t i = 0; i < m_nInputs; i++) { |
| clamped_inputs[i] = |
| pdfium::clamp(inputs[i], m_Domains[i * 2], m_Domains[i * 2 + 1]); |
| } |
| if (!v_Call(clamped_inputs.data(), results)) |
| return false; |
| |
| if (m_Ranges.empty()) |
| return true; |
| |
| for (uint32_t i = 0; i < m_nOutputs; i++) { |
| results[i] = |
| pdfium::clamp(results[i], m_Ranges[i * 2], m_Ranges[i * 2 + 1]); |
| } |
| return true; |
| } |
| |
| // See PDF Reference 1.7, page 170. |
| float CPDF_Function::Interpolate(float x, |
| float xmin, |
| float xmax, |
| float ymin, |
| float ymax) const { |
| float divisor = xmax - xmin; |
| return ymin + (divisor ? (x - xmin) * (ymax - ymin) / divisor : 0); |
| } |
| |
| const CPDF_SampledFunc* CPDF_Function::ToSampledFunc() const { |
| return m_Type == Type::kType0Sampled |
| ? static_cast<const CPDF_SampledFunc*>(this) |
| : nullptr; |
| } |
| |
| const CPDF_ExpIntFunc* CPDF_Function::ToExpIntFunc() const { |
| return m_Type == Type::kType2ExponentialInterpolation |
| ? static_cast<const CPDF_ExpIntFunc*>(this) |
| : nullptr; |
| } |
| |
| const CPDF_StitchFunc* CPDF_Function::ToStitchFunc() const { |
| return m_Type == Type::kType3Stitching |
| ? static_cast<const CPDF_StitchFunc*>(this) |
| : nullptr; |
| } |