游程编码压缩及解压缩

 1 // 栅格数据游程编码后解压缩.cpp : 定义控制台应用程序的入口点。
 2 //
 3 
 4 #include "stdafx.h"
 5 #include "Graph.h"
 6 #include "malloc.h"
 7 
 8 void drawpicture(unsigned R[]);
 9 
10 int _tmain(int argc, _TCHAR* argv[])
11 {
12     unsigned * a=NULL,* b=NULL,* c=NULL;
13 
14     FILE* fp = fopen("../图片int.dat", "rb");//二进制文件读操作
15     if (fp)
16     {
17         //读入数组
18         int width, height;
19         fread(&width, sizeof(int), 1, fp);
20         fread(&height, sizeof(int), 1, fp);
21 
22         a = (unsigned*)malloc(sizeof(unsigned)* (width * height + 2));
23         a[0] = width;
24         a[1] = height;
25         fread(a + 2, sizeof(unsigned), width*height, fp);
26     }
27     fclose(fp);
28     
29 
30     printf("原图为：");
31     drawpicture(a);
32 
33 
34     //游程编码压缩
35     int w = 2 + a[0]*a[1];
36 
37     b = (unsigned*)malloc(sizeof(unsigned)* (2 * w));
38     b[0] = a[0];
39     b[1] = a[1];
40     int j = 3, t = a[2];
41     for (int i = 3; i <= w; i++)//b[2]存放的是b[2]到数组末尾一共的元素个数
42     {
43         int n = 1;
44         for (; i < w && a[i] == t; i++)
45             n++;
46         
47         b[j++] = t;
48         b[j++] = n;
49         
50         if (i < w)
51             t = a[i];
52         else
53             break;
54     }
55     b[2] = j;
56     printf("压缩完成.");
57     //压缩完毕
58     
59     //解压缩
60 
61     c = (unsigned*)malloc(sizeof(unsigned)* (b[0] * b[1] + 2));
62     c[0] = b[0];
63     c[1] = b[1];
64     int k = 2;
65     for (int i = 3; i<b[2]; i += 2)
66     {
67         for (j = 0; j < b[i + 1]; j++)
68             c[k++] = b[i];
69     }
70     //解压完毕
71 
72     clearWindow();
73     printf("现在图为：");
74     drawpicture(c);
75     clearWindow();
76 }
77 
78 void drawpicture(unsigned R[])
79 {
80     setOrig(100,100);
81 
82     for (int i = 0; i < R[0] * R[1]; i++)
83     {
84         setPixel(i % R[0], i / R[0], R[i + 2]);
85     }
86     getchar();
87 
88     clearWindow();
89 
90     return ;
91 }