我正在尝试阅读并重新编写PGM图像,尽管这会导致形状迷失方向。右图是原始图像,左图是重新创建的图像:
这是我正在使用的代码:
#include <iostream>
#include <string>
#include <fstream>
#include <sstream>
using namespace std;
int main()
{
int row = 0, col = 0, num_of_rows = 0, max_val = 0;
stringstream data;
ifstream image ( "3.pgm" );
string inputLine = "";
getline ( image, inputLine ); // read the first line : P5
data << image.rdbuf();
data >> row >> col >> max_val;
cout << row << " " << col << " " << max_val << endl;
static float array[11000][5000] = {};
unsigned char pixel ;
for ( int i = 0; i < row; i++ )
{
for ( int j = 0; j < col; j++ )
{
data >> pixel;
array[j][i] = pixel;
}
}
ofstream newfile ( "z.pgm" );
newfile << "P5 " << endl << row << " " << col << " " << endl << max_val << endl;
for ( int i = 0; i < row; i++ )
{
for ( int j = 0; j < col; j++ )
{
pixel = array[j][i];
newfile << pixel;
}
}
image.close();
newfile.close();
}
我做错了什么?
答案 0 :(得分:0)
以二进制文件打开image
:
ifstream image("3.pgm", ios::binary);
阅读所有标题信息:
image >> inputLine >> col >> row >> max_val;
创建一行x col矩阵:
vector< vector<unsigned char> > array(row, vector<unsigned char>(col));
读入二进制数据:
for (int i = 0; i < row; i++)
for (int j = 0; j < col; j++)
image.read(reinterpret_cast<char*>(&array[i][j]), 1);
或
for (int i = 0; i < row; i++)
image.read(reinterpret_cast<char*>(&array[i][0]), col);
以二进制模式打开输出文件:
ofstream newfile("z.pgm", ios::binary);
写标题信息:
newfile << "P5" << endl << col << " " << row << endl << max_val << endl;
写出二进制数据:
for (int i = 0; i < row; i++)
for (int j = 0; j < col; j++)
newfile.write(reinterpret_cast<const char*>(&array[i][j]), 1);
或
for (int i = 0; i < row; i++)
newfile.write(reinterpret_cast<const char*>(&array[i][0]), col);