cpp-bmp-reader/bmpimage.cpp

68 lines
2.6 KiB
C++

#include "bmpimage.h"
BMPImage::BMPImage(BitmapFileHeader &fileHeader, BITMAPINFOHEADER &infoHeader, Pixel **pixelArray) {
this->fileHeader = fileHeader;
this->infoHeader = infoHeader;
this->pixelArray = pixelArray;
}
const uint32_t &BMPImage::width() const { return this->infoHeader.BitmapWidth; }
const uint32_t &BMPImage::height() const { return this->infoHeader.BitmapHeight; }
void BMPImage::write(const std::string &filename) {
{
std::ofstream ofs(filename, std::ios_base::binary);
ofs.write((char *) &this->fileHeader, sizeof(this->fileHeader));
ofs.write((char *) &this->infoHeader, sizeof(this->infoHeader));
uint32_t byteByRow = this->infoHeader.BitmapWidth * 3;
uint8_t padding = 4 - this->infoHeader.BitmapWidth % 4;
for (int i = 0; i < this->infoHeader.BitmapHeight; ++i) {
ofs.write((char *) pixelArray[i], byteByRow);
if (padding != 4) ofs.write(PADDING_ZEROES, padding); // Write padding
}
}
}
BMPImage readBMPImage(const std::string &filename) {
BitmapFileHeader bitmapFileHeader;
BITMAPINFOHEADER bitmapInfoHeader;
Pixel **pixelArray;
uint32_t DIB_Header_Size;
{
std::ifstream ifs(filename, std::ios_base::binary);
if (!ifs.good()) {
throw std::runtime_error("File read error");
}
ifs.seekg(0, std::ios::beg);
ifs.read((char *) &bitmapFileHeader, sizeof(bitmapFileHeader));
ifs.read((char *) &DIB_Header_Size, sizeof(DIB_Header_Size));
}
if (DIB_Header_Size != 40) {
throw std::runtime_error("Invalid header");
}
{
std::ifstream ifs(filename, std::ios_base::binary);
if (!ifs.good()) {
throw std::runtime_error("File read error");
}
ifs.seekg(14, std::ios::beg);
ifs.read((char *) &bitmapInfoHeader, sizeof(bitmapInfoHeader));
}
pixelArray = new Pixel *[bitmapInfoHeader.BitmapHeight];
{
std::ifstream ifs(filename, std::ios_base::binary);
if (!ifs.good()) {
throw std::runtime_error("File read error");
}
ifs.seekg(bitmapFileHeader.imageDataOffset, std::ios::beg);
uint32_t byteByRow = bitmapInfoHeader.BitmapWidth * 3;
uint8_t padding = 4 - bitmapInfoHeader.BitmapWidth % 4;
for (int i = 0; i < bitmapInfoHeader.BitmapHeight; ++i) {
pixelArray[i] = new Pixel[bitmapInfoHeader.BitmapWidth];
ifs.read((char *) pixelArray[i], byteByRow);
if (padding != 4) ifs.seekg(padding, std::ios_base::cur); // Skip padding
}
}
return {bitmapFileHeader, bitmapInfoHeader, pixelArray};
}