49 template<typename Real>
65   Real* MutablePixel(int x, int y);
66   Real  Pixel(int x, int y) const;
67   Real* MutablePixelFromLinearIndex(int index);
68   Real  PixelFromLinearIndex(int index) const;
74   void operator+=(Real a);
76   void operator*=(Real a);
83   bool SetData(const std::vector<Real>& new_data);
84   const std::vector<Real>& data() const;
88   std::vector<Real> data_;
93 template<typename Real>
94 PGMImage<Real>::PGMImage(int width, int height)  in PGMImage()
98 template<typename Real>
99 PGMImage<Real>::PGMImage(std::string filename) {  in PGMImage()
106 template<typename Real>
107 void PGMImage<Real>::Set(double constant) {  in Set()
113 template<typename Real>
114 int PGMImage<Real>::width() const {  in width()
118 template<typename Real>
119 int PGMImage<Real>::height() const {  in height()
123 template<typename Real>
124 int PGMImage<Real>::NumPixels() const {  in NumPixels()
128 template<typename Real>
129 Real* PGMImage<Real>::MutablePixel(int x, int y) {  in MutablePixel()
133 template<typename Real>
134 Real PGMImage<Real>::Pixel(int x, int y) const {  in Pixel()
138 template<typename Real>
139 Real* PGMImage<Real>::MutablePixelFromLinearIndex(int index) {  in MutablePixelFromLinearIndex()
146 template<typename Real>
147 Real  PGMImage<Real>::PixelFromLinearIndex(int index) const {  in PixelFromLinearIndex()
154 template<typename Real>
155 int PGMImage<Real>::LinearIndex(int x, int y) const {  in LinearIndex()
160 template<typename Real>
161 void PGMImage<Real>::operator+= (const PGMImage<Real>& image) {
169 template<typename Real>
170 void PGMImage<Real>::operator+= (Real a) {
177 template<typename Real>
178 void PGMImage<Real>::operator*= (Real a) {
184 template<typename Real>
185 bool PGMImage<Real>::WriteToFile(std::string filename) const {  in WriteToFile()
232 template<typename Real>
233 bool PGMImage<Real>::ReadFromFile(std::string filename) {  in ReadFromFile()
300 template<typename Real>
301 bool PGMImage<Real>::SetData(const std::vector<Real>& new_data) {  in SetData()
310 template<typename Real>
311 const std::vector<Real>& PGMImage<Real>::data() const {  in data()