From 6f0a0219b3f7e4967c160587006bf2e442a47286 Mon Sep 17 00:00:00 2001 From: Stephen Seo Date: Sat, 27 Nov 2021 13:22:23 +0900 Subject: [PATCH] Move image.cc fns to same order as in image.h --- src/image.cc | 902 +++++++++++++++++++++++++-------------------------- 1 file changed, 451 insertions(+), 451 deletions(-) diff --git a/src/image.cc b/src/image.cc index 5ebffc1..3d4eef8 100644 --- a/src/image.cc +++ b/src/image.cc @@ -211,457 +211,6 @@ bool Image::SaveAsPPM(const char *filename, bool overwrite, bool 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 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(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(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(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) { // values taken from Wikipedia article about conversion of color to grayscale double y_linear = 0.2126 * (red / 255.0) + 0.7152 * (green / 255.0) + @@ -1152,3 +701,454 @@ OpenCLHandle::Ptr Image::GetOpenCLHandle() { 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 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(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(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(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; + } +}