1 #include <iostream>
 2 #include <vector>
 3 #include <fstream>
 4 #include <string>
 5 #include <cmath>
 6 #include <Windows.h>
 7 
 8 using namespace std;
 9 
10 string getFileData(ifstream &ifile);
11 size_t getFileLength(ifstream &ifile);
12 bool saveToFile(const string &fname, const string &data);
13 SIZE getSizeByLength(size_t len);
14 
15 int main(int num, char **params)
16 {
17     if (num == 3)
18     {
19         ifstream ifile(params[1]);
20         auto &&data = getFileData(ifile);
21         saveToFile(params[2], data);
22         cout << "转成成功!" << endl;
23     }
24     else
25     {
26         cout << "输入参数: 文本文件 位图文件" << endl;
27     }
28     return 0;
29 }
30 
31 string getFileData(ifstream &ifile)
32 {
33     auto length = getFileLength(ifile);
34     auto data = string(length, ‘\0‘);
35     ifile.read(&data[0], length);
36     return data;
37 }
38 
39 size_t getFileLength(ifstream &ifile)
40 {
41     ifile.seekg(0, ios::end);
42     size_t len = (size_t)ifile.tellg();
43     ifile.seekg(0, ios::beg);
44     return len;
45 }
46 
47 bool saveToFile(const string &fname, const string &data)
48 {
49     auto size = getSizeByLength(data.size() / 3);
50     auto lineWidth = (size.cx * 3 + 3) / 4 * 4;
51 
52     BITMAPFILEHEADER bfh;
53     bfh.bfSize = 54 + lineWidth * 5;
54     bfh.bfType = 0x4D42;
55     bfh.bfOffBits = 54;
56     bfh.bfReserved1 = 0;
57     bfh.bfReserved2 = 0;
58 
59     BITMAPINFOHEADER bih;
60     bih.biSize = sizeof(BITMAPINFOHEADER);
61     bih.biPlanes = 1;
62     bih.biWidth = size.cx;
63     bih.biHeight = size.cy;
64     bih.biBitCount = 24;
65     bih.biClrUsed = 0;
66     bih.biClrImportant = 0;
67     bih.biXPelsPerMeter = 3780;
68     bih.biYPelsPerMeter = 3780;
69     bih.biCompression = BI_RGB;
70     bih.biSizeImage = lineWidth * bih.biHeight;
71 
72     ofstream ofile(fname);
73     ofile.write( (const char *)&bfh, sizeof(BITMAPFILEHEADER) );
74     ofile.write( (const char *)&bih, sizeof(BITMAPINFOHEADER) );
75     ofile.write( (const char *)&data[0], bih.biSizeImage );
76     ofile.close();
77 
78     return true;
79 }
80 
81 SIZE getSizeByLength(size_t len)
82 {
83     static int widths[] = {2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, 2048};
84     auto index = 0;
85     while (
86         index < sizeof(widths) / sizeof(int) && 
87         widths[index] * widths[index] < (int)len )
88     {
89         ++index;
90     }
91     int width = widths[index];
92     int height = (int)(len / width + 0.9f);
93 
94     SIZE size = { width, height };
95     return size;
96 }