Расширяя то, что написал Йола, он сможет читать и выводить файл. Это не очень хорошо проверено, но, кажется, работает. При выводе он использует формат файла, который читает.
#include <iostream>
#include <unistd.h>
#include <fstream>
using std::cout;
using std::endl;
using std::ofstream;
using std::ifstream;
#pragma pack(1)
#pragma once
typedef int LONG;
typedef unsigned short WORD;
typedef unsigned int DWORD;
typedef struct tagBITMAPFILEHEADER {
WORD bfType;
DWORD bfSize;
WORD bfReserved1;
WORD bfReserved2;
DWORD bfOffBits;
} BITMAPFILEHEADER, *PBITMAPFILEHEADER;
typedef struct tagBITMAPINFOHEADER {
DWORD biSize;
LONG biWidth;
LONG biHeight;
WORD biPlanes;
WORD biBitCount;
DWORD biCompression;
DWORD biSizeImage;
LONG biXPelsPerMeter;
LONG biYPelsPerMeter;
DWORD biClrUsed;
DWORD biClrImportant;
} BITMAPINFOHEADER, *PBITMAPINFOHEADER;
unsigned char** reds;
unsigned char** greens;
unsigned char** blues;
int rows;
int cols;
void ColorTest() {
// Makes Red Rectangle in top left corner. Rectangle stretches to right alot
for (int i = rows / 10; i < 3 * rows / 10; i++)
for (int j = cols / 10; j < 7 * cols / 10; j++)
reds[i][j] = 0xff;
// Makes small green box in bottom right
for (int i = 8 * rows / 10; i < rows; i++)
for (int j = 8 * cols / 10; j < cols; j++)
greens[i][j] = 0xff;
// Makes White box in the middle of the screeene
for (int i = rows * 4 / 10; i < rows * 6 / 10; i++)
for (int j = cols * 4 / 10; j < cols * 6 / 10; j++) {
greens[i][j] = 0xff;
reds[i][j] = 0xff;
blues[i][j] = 0xff;
}
// Blue verticle rectangle bottom left
for (int i = rows * 6 / 10; i < rows; i++)
for (int j = cols * 0; j < cols * 1 / 10; j++)
blues[i][j] = 0xff;
}
void RGB_Allocate(unsigned char**& dude) {
dude = new unsigned char*[rows];
for (int i = 0; i < rows; i++)
dude[i] = new unsigned char[cols];
}
bool FillAndAllocate(char*& buffer, const char* Picture, int& rows, int& cols, int& BufferSize) { //Returns 1 if executed sucessfully, 0 if not sucessfull
std::ifstream file(Picture);
if (file) {
file.seekg(0, std::ios::end);
std::streampos length = file.tellg();
file.seekg(0, std::ios::beg);
buffer = new char[length];
file.read(&buffer[0], length);
PBITMAPFILEHEADER file_header;
PBITMAPINFOHEADER info_header;
file_header = (PBITMAPFILEHEADER) (&buffer[0]);
info_header = (PBITMAPINFOHEADER) (&buffer[0] + sizeof(BITMAPFILEHEADER));
rows = info_header->biHeight;
cols = info_header->biWidth;
BufferSize = file_header->bfSize;
return 1;
}
else {
cout << "File" << Picture << " don't Exist!" << endl;
return 0;
}
}
void GetPixlesFromBMP24(unsigned char** reds, unsigned char** greens, unsigned char** blues, int end, int rows, int cols, char* FileReadBuffer) { // end is BufferSize (total size of file)
int count = 1;
int extra = cols % 4; // The nubmer of bytes in a row (cols) will be a multiple of 4.
for (int i = 0; i < rows; i++){
count += extra;
for (int j = cols - 1; j >= 0; j--)
for (int k = 0; k < 3; k++) {
switch (k) {
case 0:
reds[i][j] = FileReadBuffer[end - count++];
break;
case 1:
greens[i][j] = FileReadBuffer[end - count++];
break;
case 2:
blues[i][j] = FileReadBuffer[end - count++];
break;
}
}
}
}
void WriteOutBmp24(char* FileBuffer, const char* NameOfFileToCreate, int BufferSize) {
std::ofstream write(NameOfFileToCreate);
if (!write) {
cout << "Failed to write " << NameOfFileToCreate << endl;
return;
}
int count = 1;
int extra = cols % 4; // The nubmer of bytes in a row (cols) will be a multiple of 4.
for (int i = 0; i < rows; i++){
count += extra;
for (int j = cols - 1; j >= 0; j--)
for (int k = 0; k < 3; k++) {
switch (k) {
case 0: //reds
FileBuffer[BufferSize - count] = reds[i][j];
break;
case 1: //green
FileBuffer[BufferSize - count] = greens[i][j];
break;
case 2: //blue
FileBuffer[BufferSize - count] = blues[i][j];
break;
}
count++;
}
}
write.write(FileBuffer, BufferSize);
}
int main(int args, char** cat) {
char* FileBuffer; int BufferSize;
#define Picture "ReadInPicture.bmp"
if (!FillAndAllocate(FileBuffer, Picture, rows, cols, BufferSize)){cout << "File read error" << endl; return 0;}
cout << "Rows: " << rows << " Cols: " << cols << endl;
RGB_Allocate(reds);
RGB_Allocate(greens);
RGB_Allocate(blues);
GetPixlesFromBMP24( reds, greens, blues,BufferSize, rows, cols, FileBuffer);
ColorTest();
#define WriteOutFile "OutputPicture.bmp"
WriteOutBmp24(FileBuffer, WriteOutFile,BufferSize);
return 1;
}