Move image.cc fns to same order as in image.h

This commit is contained in:
Stephen Seo 2021-11-27 13:22:23 +09:00
parent a2535ce630
commit 6f0a0219b3

View file

@ -211,457 +211,6 @@ bool Image::SaveAsPPM(const char *filename, bool overwrite, bool packed) {
return SaveAsPPM(std::string(filename), overwrite, packed); return SaveAsPPM(std::string(filename), overwrite, packed);
} }
void Image::DecodePNG(const std::string &filename) {
FILE *file = std::fopen(filename.c_str(), "rb");
// Check header of file to check if it is actually a png file.
{
std::array<unsigned char, 8> buf;
if (std::fread(buf.data(), 1, 8, file) != 8) {
std::fclose(file);
std::cout << "ERROR: File \"" << filename << "\" is smaller than 8 bytes"
<< std::endl;
return;
} else if (png_sig_cmp(reinterpret_cast<png_const_bytep>(buf.data()), 0,
8) != 0) {
// not png file, do nothing
std::fclose(file);
std::cout << "ERROR: File \"" << filename << "\" is not a png file"
<< std::endl;
return;
}
}
// seek to head of file
std::rewind(file);
// init required structs for png decoding
png_structp png_ptr =
png_create_read_struct(PNG_LIBPNG_VER_STRING, nullptr, nullptr, nullptr);
if (!png_ptr) {
std::cout << "ERROR: Failed to initialize libpng (png_ptr) for decoding "
"PNG file \""
<< filename << '"' << std::endl;
std::fclose(file);
return;
}
png_infop png_info_ptr = png_create_info_struct(png_ptr);
if (!png_info_ptr) {
std::cout << "ERROR: Failed to initialize libpng (png_infop) for decoding "
"PNG file \""
<< filename << '"' << std::endl;
png_destroy_read_struct(&png_ptr, nullptr, nullptr);
std::fclose(file);
return;
}
png_infop png_end_info_ptr = png_create_info_struct(png_ptr);
if (!png_end_info_ptr) {
std::cout << "ERROR: Failed to initialize libpng (end png_infop) for "
"decoding PNG file \""
<< filename << '"' << std::endl;
png_destroy_read_struct(&png_ptr, &png_info_ptr, nullptr);
std::fclose(file);
return;
}
// required to handle libpng errors
if (setjmp(png_jmpbuf(png_ptr))) {
png_destroy_read_struct(&png_ptr, &png_info_ptr, &png_end_info_ptr);
std::fclose(file);
return;
}
// pass the FILE pointer to libpng
png_init_io(png_ptr, file);
// have libpng process the png data
png_read_png(png_ptr, png_info_ptr, PNG_TRANSFORM_IDENTITY, nullptr);
// get image width (in pixels)
width_ = png_get_image_width(png_ptr, png_info_ptr);
// get image height (in pixels)
height_ = png_get_image_height(png_ptr, png_info_ptr);
// get channel count of image
unsigned int channels = png_get_channels(png_ptr, png_info_ptr);
if (channels == 1) {
is_grayscale_ = true;
} else {
is_grayscale_ = false;
}
if (height_ > PNG_UINT_32_MAX) {
png_error(png_ptr, "Image is too tall to process in memory");
} else if (width_ > PNG_UINT_32_MAX) {
png_error(png_ptr, "Image is too wide to process in memory");
}
png_byte **row_pointers = png_get_rows(png_ptr, png_info_ptr);
data_.clear();
if (channels == 3 || channels == 4) {
data_.reserve(width_ * 4 * height_);
} else if (channels == 1) {
data_.reserve(width_ * height_);
} else {
std::cout << "ERROR: PNG has invalid channel count == " << channels
<< std::endl;
png_destroy_read_struct(&png_ptr, &png_info_ptr, &png_end_info_ptr);
return;
}
for (unsigned int y = 0; y < height_; ++y) {
for (unsigned int x = 0; x < width_; ++x) {
if (is_grayscale_) {
data_.push_back(row_pointers[y][x]);
} else if (channels == 3) {
for (unsigned int c = 0; c < channels; ++c) {
data_.push_back(row_pointers[y][x * channels + c]);
}
data_.push_back(255);
} else /* if (channels == 4) */ {
for (unsigned int c = 0; c < channels; ++c) {
data_.push_back(row_pointers[y][x * channels + c]);
}
}
}
}
// cleanup
png_destroy_read_struct(&png_ptr, &png_info_ptr, &png_end_info_ptr);
fclose(file);
// verify
if (is_grayscale_) {
if (data_.size() != width_ * height_) {
std::cout << "WARNING: data_.size() doesn't match width_ * height_"
<< std::endl;
}
} else {
if (data_.size() != 4 * width_ * height_) {
std::cout << "WARNING: data_.size() doesn't match 4 * width_ * height_"
<< std::endl;
}
}
}
void Image::DecodePGM(const std::string &filename) {
is_grayscale_ = true;
std::ifstream ifs(filename);
if (!ifs.is_open()) {
std::cout << "ERROR: Failed to open file \"" << filename << '"'
<< std::endl;
return;
}
std::string str_input;
int int_input;
ifs >> str_input;
if (!ifs.good()) {
std::cout << "ERROR: Failed to parse file (PGM first identifier) \""
<< filename << '"' << std::endl;
return;
}
if (str_input.compare("P2") == 0) {
// data stored in ascii format
// get width
ifs >> int_input;
if (!ifs.good() || int_input <= 0) {
std::cout << "ERROR: Failed to parse file (PGM width) \"" << filename
<< '"' << std::endl;
return;
}
width_ = int_input;
// get height
ifs >> int_input;
if (!ifs.good() || int_input <= 0) {
std::cout << "ERROR: Failed to parse file (PGM height) \"" << filename
<< '"' << std::endl;
return;
}
height_ = int_input;
// get max_value
ifs >> int_input;
if (!ifs.good() || int_input <= 0) {
std::cout << "ERROR: Failed to parse file (PGM max) \"" << filename << '"'
<< std::endl;
return;
}
float max_value = int_input;
// parse data
data_.clear();
data_.reserve(width_ * height_);
float value;
for (unsigned int i = 0; i < width_ * height_; ++i) {
ifs >> int_input;
if (!ifs.good()) {
std::cout << "ERROR: Failed to parse file (PGM data) \"" << filename
<< '"' << std::endl;
return;
}
value = static_cast<float>(int_input) / max_value;
data_.push_back(std::round(value * 255.0F));
}
} else if (str_input.compare("P5") == 0) {
// data stored in raw format
// get width
ifs >> int_input;
if (!ifs.good() || int_input <= 0) {
std::cout << "ERROR: Failed to parse file (PGM width) \"" << filename
<< '"' << std::endl;
return;
}
width_ = int_input;
// get height
ifs >> int_input;
if (!ifs.good() || int_input <= 0) {
std::cout << "ERROR: Failed to parse file (PGM height) \"" << filename
<< '"' << std::endl;
return;
}
height_ = int_input;
// get max_value
ifs >> int_input;
if (!ifs.good() || int_input <= 0) {
std::cout << "ERROR: Failed to parse file (PGM max) \"" << filename << '"'
<< std::endl;
return;
}
int max_value_int = int_input;
float max_value = int_input;
// validate max_value
if (max_value_int != 255 && max_value_int != 65535) {
std::cout << "ERROR: Invalid max value for PGM (should be 255 or 65535) "
"(filename \""
<< filename << "\")" << std::endl;
return;
}
// extract whitespace before data
{
int c = ifs.get();
if (c != '\n' && c != ' ') {
std::cout << "WARNING: File data after PGM max is not whitespace "
"(filename \""
<< filename << "\")"
<< " value is " << c << std::endl;
}
if (!ifs.good()) {
std::cout << "ERROR: Failed to parse file (PGM after whitespace) \""
<< filename << '"' << std::endl;
return;
}
}
// parse raw data
data_.clear();
data_.reserve(width_ * height_);
float value;
for (unsigned int i = 0; i < width_ * height_; ++i) {
if (max_value_int == 255) {
value = ifs.get() / max_value;
data_.push_back(std::round(value * 255.0F));
if (!ifs.good()) {
std::cout << "ERROR: Failed to parse file (PGM data) \"" << filename
<< '"' << std::endl;
return;
}
} else /* if (max_value_int == 65535) */ {
value = (ifs.get() & 0xFF) | ((ifs.get() << 8) & 0xFF00);
value /= max_value;
data_.push_back(std::round(value * 255.0F));
if (!ifs.good()) {
std::cout << "ERROR: Failed to parse file (PGM data 16-bit) \""
<< filename << '"' << std::endl;
return;
}
}
}
if (ifs.get() != decltype(ifs)::traits_type::eof()) {
std::cout << "WARNING: Trailing data in PGM file \"" << filename << '"'
<< std::endl;
}
} else {
std::cout << "ERROR: Invalid \"magic number\" in header of file \""
<< filename << '"' << std::endl;
}
}
void Image::DecodePPM(const std::string &filename) {
is_grayscale_ = false;
std::ifstream ifs(filename);
if (!ifs.is_open()) {
std::cout << "ERROR: Failed to open file \"" << filename << '"'
<< std::endl;
return;
}
std::string str_input;
int int_input;
ifs >> str_input;
if (!ifs.good()) {
std::cout << "ERROR: Failed to parse file (PPM first identifier) \""
<< filename << '"' << std::endl;
return;
}
if (str_input.compare("P3") == 0) {
// data stored in ascii format
// get width
ifs >> int_input;
if (!ifs.good() || int_input <= 0) {
std::cout << "ERROR: Failed to parse file (PPM width) \"" << filename
<< '"' << std::endl;
return;
}
width_ = int_input;
// get height
ifs >> int_input;
if (!ifs.good() || int_input <= 0) {
std::cout << "ERROR: Failed to parse file (PPM height) \"" << filename
<< '"' << std::endl;
return;
}
height_ = int_input;
// get max_value
ifs >> int_input;
if (!ifs.good() || int_input <= 0) {
std::cout << "ERROR: Failed to parse file (PPM max) \"" << filename << '"'
<< std::endl;
return;
}
float max_value = int_input;
// parse data
data_.clear();
data_.reserve(width_ * height_ * 4);
float value;
for (unsigned int i = 0; i < width_ * height_ * 3; ++i) {
ifs >> int_input;
if (!ifs.good()) {
std::cout << "ERROR: Failed to parse file (PPM data) \"" << filename
<< '"' << std::endl;
return;
}
value = static_cast<float>(int_input) / max_value;
data_.push_back(std::round(value * 255.0F));
if (i % 3 == 2) {
// PPM is RGB but Image stores as RGBA
data_.push_back(255);
}
}
} else if (str_input.compare("P6") == 0) {
// data stored in raw format
// get width
ifs >> int_input;
if (!ifs.good() || int_input <= 0) {
std::cout << "ERROR: Failed to parse file (PPM width) \"" << filename
<< '"' << std::endl;
return;
}
width_ = int_input;
// get height
ifs >> int_input;
if (!ifs.good() || int_input <= 0) {
std::cout << "ERROR: Failed to parse file (PPM height) \"" << filename
<< '"' << std::endl;
return;
}
height_ = int_input;
// get max_value
ifs >> int_input;
if (!ifs.good() || int_input <= 0) {
std::cout << "ERROR: Failed to parse file (PPM max) \"" << filename << '"'
<< std::endl;
return;
}
int max_value_int = int_input;
float max_value = int_input;
// validate max_value
if (max_value_int != 255 && max_value_int != 65535) {
std::cout << "ERROR: Invalid max value for PPM (should be 255 or 65535) "
"(filename \""
<< filename << "\")" << std::endl;
return;
}
// extract whitespace before data
{
int c = ifs.get();
if (c != '\n' && c != ' ') {
std::cout
<< "WARNING: File data after PPM max is not whitespace (filename \""
<< filename << "\") value is " << c << std::endl;
}
if (!ifs.good()) {
std::cout << "ERROR: Failed to parse file (PPM after whitespace) \""
<< filename << '"' << std::endl;
return;
}
}
// parse raw data
data_.clear();
data_.reserve(width_ * height_ * 4);
float value;
for (unsigned int i = 0; i < width_ * height_ * 3; ++i) {
if (max_value_int == 255) {
value = ifs.get() / max_value;
data_.push_back(std::round(value * 255.0F));
if (!ifs.good()) {
std::cout << "ERROR: Failed to parse file (PPM data) \"" << filename
<< '"' << std::endl;
return;
}
} else /* if (max_value_int == 65535) */ {
value = (ifs.get() & 0xFF) | ((ifs.get() << 8) & 0xFF00);
value /= max_value;
data_.push_back(std::round(value * 255.0F));
if (!ifs.good()) {
std::cout << "ERROR: Failed to parse file (PPM data 16-bit) \""
<< filename << '"' << std::endl;
return;
}
}
if (i % 3 == 2) {
// PPM is RGB but Image stores as RGBA
data_.push_back(255);
}
}
if (ifs.get() != decltype(ifs)::traits_type::eof()) {
std::cout << "WARNING: Trailing data in PPM file \"" << filename << '"'
<< std::endl;
}
} else {
std::cout << "ERROR: Invalid \"magic number\" in header of file \""
<< filename << '"' << std::endl;
}
}
uint8_t Image::ColorToGray(uint8_t red, uint8_t green, uint8_t blue) { uint8_t Image::ColorToGray(uint8_t red, uint8_t green, uint8_t blue) {
// values taken from Wikipedia article about conversion of color to grayscale // values taken from Wikipedia article about conversion of color to grayscale
double y_linear = 0.2126 * (red / 255.0) + 0.7152 * (green / 255.0) + double y_linear = 0.2126 * (red / 255.0) + 0.7152 * (green / 255.0) +
@ -1152,3 +701,454 @@ OpenCLHandle::Ptr Image::GetOpenCLHandle() {
return opencl_handle_; return opencl_handle_;
} }
void Image::DecodePNG(const std::string &filename) {
FILE *file = std::fopen(filename.c_str(), "rb");
// Check header of file to check if it is actually a png file.
{
std::array<unsigned char, 8> buf;
if (std::fread(buf.data(), 1, 8, file) != 8) {
std::fclose(file);
std::cout << "ERROR: File \"" << filename << "\" is smaller than 8 bytes"
<< std::endl;
return;
} else if (png_sig_cmp(reinterpret_cast<png_const_bytep>(buf.data()), 0,
8) != 0) {
// not png file, do nothing
std::fclose(file);
std::cout << "ERROR: File \"" << filename << "\" is not a png file"
<< std::endl;
return;
}
}
// seek to head of file
std::rewind(file);
// init required structs for png decoding
png_structp png_ptr =
png_create_read_struct(PNG_LIBPNG_VER_STRING, nullptr, nullptr, nullptr);
if (!png_ptr) {
std::cout << "ERROR: Failed to initialize libpng (png_ptr) for decoding "
"PNG file \""
<< filename << '"' << std::endl;
std::fclose(file);
return;
}
png_infop png_info_ptr = png_create_info_struct(png_ptr);
if (!png_info_ptr) {
std::cout << "ERROR: Failed to initialize libpng (png_infop) for decoding "
"PNG file \""
<< filename << '"' << std::endl;
png_destroy_read_struct(&png_ptr, nullptr, nullptr);
std::fclose(file);
return;
}
png_infop png_end_info_ptr = png_create_info_struct(png_ptr);
if (!png_end_info_ptr) {
std::cout << "ERROR: Failed to initialize libpng (end png_infop) for "
"decoding PNG file \""
<< filename << '"' << std::endl;
png_destroy_read_struct(&png_ptr, &png_info_ptr, nullptr);
std::fclose(file);
return;
}
// required to handle libpng errors
if (setjmp(png_jmpbuf(png_ptr))) {
png_destroy_read_struct(&png_ptr, &png_info_ptr, &png_end_info_ptr);
std::fclose(file);
return;
}
// pass the FILE pointer to libpng
png_init_io(png_ptr, file);
// have libpng process the png data
png_read_png(png_ptr, png_info_ptr, PNG_TRANSFORM_IDENTITY, nullptr);
// get image width (in pixels)
width_ = png_get_image_width(png_ptr, png_info_ptr);
// get image height (in pixels)
height_ = png_get_image_height(png_ptr, png_info_ptr);
// get channel count of image
unsigned int channels = png_get_channels(png_ptr, png_info_ptr);
if (channels == 1) {
is_grayscale_ = true;
} else {
is_grayscale_ = false;
}
if (height_ > PNG_UINT_32_MAX) {
png_error(png_ptr, "Image is too tall to process in memory");
} else if (width_ > PNG_UINT_32_MAX) {
png_error(png_ptr, "Image is too wide to process in memory");
}
png_byte **row_pointers = png_get_rows(png_ptr, png_info_ptr);
data_.clear();
if (channels == 3 || channels == 4) {
data_.reserve(width_ * 4 * height_);
} else if (channels == 1) {
data_.reserve(width_ * height_);
} else {
std::cout << "ERROR: PNG has invalid channel count == " << channels
<< std::endl;
png_destroy_read_struct(&png_ptr, &png_info_ptr, &png_end_info_ptr);
return;
}
for (unsigned int y = 0; y < height_; ++y) {
for (unsigned int x = 0; x < width_; ++x) {
if (is_grayscale_) {
data_.push_back(row_pointers[y][x]);
} else if (channels == 3) {
for (unsigned int c = 0; c < channels; ++c) {
data_.push_back(row_pointers[y][x * channels + c]);
}
data_.push_back(255);
} else /* if (channels == 4) */ {
for (unsigned int c = 0; c < channels; ++c) {
data_.push_back(row_pointers[y][x * channels + c]);
}
}
}
}
// cleanup
png_destroy_read_struct(&png_ptr, &png_info_ptr, &png_end_info_ptr);
fclose(file);
// verify
if (is_grayscale_) {
if (data_.size() != width_ * height_) {
std::cout << "WARNING: data_.size() doesn't match width_ * height_"
<< std::endl;
}
} else {
if (data_.size() != 4 * width_ * height_) {
std::cout << "WARNING: data_.size() doesn't match 4 * width_ * height_"
<< std::endl;
}
}
}
void Image::DecodePGM(const std::string &filename) {
is_grayscale_ = true;
std::ifstream ifs(filename);
if (!ifs.is_open()) {
std::cout << "ERROR: Failed to open file \"" << filename << '"'
<< std::endl;
return;
}
std::string str_input;
int int_input;
ifs >> str_input;
if (!ifs.good()) {
std::cout << "ERROR: Failed to parse file (PGM first identifier) \""
<< filename << '"' << std::endl;
return;
}
if (str_input.compare("P2") == 0) {
// data stored in ascii format
// get width
ifs >> int_input;
if (!ifs.good() || int_input <= 0) {
std::cout << "ERROR: Failed to parse file (PGM width) \"" << filename
<< '"' << std::endl;
return;
}
width_ = int_input;
// get height
ifs >> int_input;
if (!ifs.good() || int_input <= 0) {
std::cout << "ERROR: Failed to parse file (PGM height) \"" << filename
<< '"' << std::endl;
return;
}
height_ = int_input;
// get max_value
ifs >> int_input;
if (!ifs.good() || int_input <= 0) {
std::cout << "ERROR: Failed to parse file (PGM max) \"" << filename << '"'
<< std::endl;
return;
}
float max_value = int_input;
// parse data
data_.clear();
data_.reserve(width_ * height_);
float value;
for (unsigned int i = 0; i < width_ * height_; ++i) {
ifs >> int_input;
if (!ifs.good()) {
std::cout << "ERROR: Failed to parse file (PGM data) \"" << filename
<< '"' << std::endl;
return;
}
value = static_cast<float>(int_input) / max_value;
data_.push_back(std::round(value * 255.0F));
}
} else if (str_input.compare("P5") == 0) {
// data stored in raw format
// get width
ifs >> int_input;
if (!ifs.good() || int_input <= 0) {
std::cout << "ERROR: Failed to parse file (PGM width) \"" << filename
<< '"' << std::endl;
return;
}
width_ = int_input;
// get height
ifs >> int_input;
if (!ifs.good() || int_input <= 0) {
std::cout << "ERROR: Failed to parse file (PGM height) \"" << filename
<< '"' << std::endl;
return;
}
height_ = int_input;
// get max_value
ifs >> int_input;
if (!ifs.good() || int_input <= 0) {
std::cout << "ERROR: Failed to parse file (PGM max) \"" << filename << '"'
<< std::endl;
return;
}
int max_value_int = int_input;
float max_value = int_input;
// validate max_value
if (max_value_int != 255 && max_value_int != 65535) {
std::cout << "ERROR: Invalid max value for PGM (should be 255 or 65535) "
"(filename \""
<< filename << "\")" << std::endl;
return;
}
// extract whitespace before data
{
int c = ifs.get();
if (c != '\n' && c != ' ') {
std::cout << "WARNING: File data after PGM max is not whitespace "
"(filename \""
<< filename << "\")"
<< " value is " << c << std::endl;
}
if (!ifs.good()) {
std::cout << "ERROR: Failed to parse file (PGM after whitespace) \""
<< filename << '"' << std::endl;
return;
}
}
// parse raw data
data_.clear();
data_.reserve(width_ * height_);
float value;
for (unsigned int i = 0; i < width_ * height_; ++i) {
if (max_value_int == 255) {
value = ifs.get() / max_value;
data_.push_back(std::round(value * 255.0F));
if (!ifs.good()) {
std::cout << "ERROR: Failed to parse file (PGM data) \"" << filename
<< '"' << std::endl;
return;
}
} else /* if (max_value_int == 65535) */ {
value = (ifs.get() & 0xFF) | ((ifs.get() << 8) & 0xFF00);
value /= max_value;
data_.push_back(std::round(value * 255.0F));
if (!ifs.good()) {
std::cout << "ERROR: Failed to parse file (PGM data 16-bit) \""
<< filename << '"' << std::endl;
return;
}
}
}
if (ifs.get() != decltype(ifs)::traits_type::eof()) {
std::cout << "WARNING: Trailing data in PGM file \"" << filename << '"'
<< std::endl;
}
} else {
std::cout << "ERROR: Invalid \"magic number\" in header of file \""
<< filename << '"' << std::endl;
}
}
void Image::DecodePPM(const std::string &filename) {
is_grayscale_ = false;
std::ifstream ifs(filename);
if (!ifs.is_open()) {
std::cout << "ERROR: Failed to open file \"" << filename << '"'
<< std::endl;
return;
}
std::string str_input;
int int_input;
ifs >> str_input;
if (!ifs.good()) {
std::cout << "ERROR: Failed to parse file (PPM first identifier) \""
<< filename << '"' << std::endl;
return;
}
if (str_input.compare("P3") == 0) {
// data stored in ascii format
// get width
ifs >> int_input;
if (!ifs.good() || int_input <= 0) {
std::cout << "ERROR: Failed to parse file (PPM width) \"" << filename
<< '"' << std::endl;
return;
}
width_ = int_input;
// get height
ifs >> int_input;
if (!ifs.good() || int_input <= 0) {
std::cout << "ERROR: Failed to parse file (PPM height) \"" << filename
<< '"' << std::endl;
return;
}
height_ = int_input;
// get max_value
ifs >> int_input;
if (!ifs.good() || int_input <= 0) {
std::cout << "ERROR: Failed to parse file (PPM max) \"" << filename << '"'
<< std::endl;
return;
}
float max_value = int_input;
// parse data
data_.clear();
data_.reserve(width_ * height_ * 4);
float value;
for (unsigned int i = 0; i < width_ * height_ * 3; ++i) {
ifs >> int_input;
if (!ifs.good()) {
std::cout << "ERROR: Failed to parse file (PPM data) \"" << filename
<< '"' << std::endl;
return;
}
value = static_cast<float>(int_input) / max_value;
data_.push_back(std::round(value * 255.0F));
if (i % 3 == 2) {
// PPM is RGB but Image stores as RGBA
data_.push_back(255);
}
}
} else if (str_input.compare("P6") == 0) {
// data stored in raw format
// get width
ifs >> int_input;
if (!ifs.good() || int_input <= 0) {
std::cout << "ERROR: Failed to parse file (PPM width) \"" << filename
<< '"' << std::endl;
return;
}
width_ = int_input;
// get height
ifs >> int_input;
if (!ifs.good() || int_input <= 0) {
std::cout << "ERROR: Failed to parse file (PPM height) \"" << filename
<< '"' << std::endl;
return;
}
height_ = int_input;
// get max_value
ifs >> int_input;
if (!ifs.good() || int_input <= 0) {
std::cout << "ERROR: Failed to parse file (PPM max) \"" << filename << '"'
<< std::endl;
return;
}
int max_value_int = int_input;
float max_value = int_input;
// validate max_value
if (max_value_int != 255 && max_value_int != 65535) {
std::cout << "ERROR: Invalid max value for PPM (should be 255 or 65535) "
"(filename \""
<< filename << "\")" << std::endl;
return;
}
// extract whitespace before data
{
int c = ifs.get();
if (c != '\n' && c != ' ') {
std::cout
<< "WARNING: File data after PPM max is not whitespace (filename \""
<< filename << "\") value is " << c << std::endl;
}
if (!ifs.good()) {
std::cout << "ERROR: Failed to parse file (PPM after whitespace) \""
<< filename << '"' << std::endl;
return;
}
}
// parse raw data
data_.clear();
data_.reserve(width_ * height_ * 4);
float value;
for (unsigned int i = 0; i < width_ * height_ * 3; ++i) {
if (max_value_int == 255) {
value = ifs.get() / max_value;
data_.push_back(std::round(value * 255.0F));
if (!ifs.good()) {
std::cout << "ERROR: Failed to parse file (PPM data) \"" << filename
<< '"' << std::endl;
return;
}
} else /* if (max_value_int == 65535) */ {
value = (ifs.get() & 0xFF) | ((ifs.get() << 8) & 0xFF00);
value /= max_value;
data_.push_back(std::round(value * 255.0F));
if (!ifs.good()) {
std::cout << "ERROR: Failed to parse file (PPM data 16-bit) \""
<< filename << '"' << std::endl;
return;
}
}
if (i % 3 == 2) {
// PPM is RGB but Image stores as RGBA
data_.push_back(255);
}
}
if (ifs.get() != decltype(ifs)::traits_type::eof()) {
std::cout << "WARNING: Trailing data in PPM file \"" << filename << '"'
<< std::endl;
}
} else {
std::cout << "ERROR: Invalid \"magic number\" in header of file \""
<< filename << '"' << std::endl;
}
}