数字图像，尤其是从宇宙飞船发回的数字图像可能会包含尖峰脉冲。为第12道编程练习题添加消除尖峰脉冲的函数。该函数应该将每一个值和它上下左右的相邻值比较，如果该值与它周围每个值的差都大于1，就用所有相邻值的平均值（取与其最接近的整数）取代这个值。注意到边界上的点的相邻点少于4个，所以它们需要特殊处理。
/* data example:
0 0 9 0 0 0 0 0 0 0 0 0 5 8 9 9 8 5 2 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 9 0 0 0 0 0 0 0 5 8 9 9 8 5 5 2 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 5 8 1 9 8 5 4 5 2 0 0 0 0 0 0 0 0 0
0 0 0 0 9 0 0 0 0 0 0 0 5 8 9 9 8 5 0 4 5 2 0 0 0 0 0 0 0 0
0 0 9 0 0 0 0 0 0 0 0 0 5 8 9 9 8 5 0 0 4 5 2 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 5 8 9 1 8 5 0 0 0 4 5 2 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 5 8 9 9 8 5 0 0 0 0 4 5 2 0 0 0 0 0
5 5 5 5 5 5 5 5 5 5 5 5 5 8 9 9 8 5 5 5 5 5 5 5 5 5 5 5 5 5
8 8 8 8 8 8 8 8 8 8 8 8 5 8 9 9 8 5 8 8 8 8 8 8 8 8 8 8 8 8
9 9 9 9 0 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 3 9 9 9 9 9 9 9
8 8 8 8 8 8 8 8 8 8 8 8 5 8 9 9 8 5 8 8 8 8 8 8 8 8 8 8 8 8
5 5 5 5 5 5 5 5 5 5 5 5 5 8 9 9 8 5 5 5 5 5 5 5 5 5 5 5 5 5
0 0 0 0 0 0 0 0 0 0 0 0 5 8 9 9 8 5 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 5 8 9 9 8 5 0 0 0 0 6 6 0 0 0 0 0 0
0 0 0 0 2 2 0 0 0 0 0 0 5 8 9 9 8 5 0 0 5 6 0 0 6 5 0 0 0 0
0 0 0 0 3 3 0 0 0 0 0 0 5 8 9 9 8 5 0 5 6 1 1 1 1 6 5 0 0 0
0 0 0 0 4 4 0 0 0 0 0 0 5 8 9 9 8 5 0 0 5 6 0 0 6 5 0 0 0 0
0 0 0 0 5 5 0 0 0 0 0 0 5 8 9 9 8 5 0 0 0 0 6 6 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 5 8 9 9 8 5 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 5 8 9 9 8 5 0 0 0 0 0 0 0 0 0 0 0 0
*/
#include <stdio.h> #include <stdlib.h> int main(void) { FILE *fp; char name[30],photo[20][31],table[] = " .':~*=&%@"; int num[20][30],row,column,i=0; printf("input the name of source file:"); gets(name); if ( ( fp=fopen(name,"r") ) == NULL ) { printf("Can't open %s",name); exit(1); } for (row=0; row<20; row++) for (column=0; column<30; column++) fscanf(fp,"%d",&num[row][column]); for (row=0; row<20; row++) for (column=0; column<30; column++) { if(row==0&&column==0) { if( (num[row][column] - num[row][column+1])>1 && (num[row][column] - num[row+1][column])>1 ) num[row][column] = ( num[row][column+1] + num[row+1][column] ) / 2 + 0.5;//加0.5是为了四舍五入 } else if(row==0&&column==29) { if( (num[row][column] - num[row][column-1])>1 && (num[row][column] - num[row+1][column])>1 ) num[row][column] = ( num[row][column-1] + num[row+1][column] ) / 2 + 0.5; } else if(row==19&&column==0) { if( (num[row][column] - num[row-1][column])>1 && (num[row][column] - num[row][column+1])>1 ) num[row][column] = ( num[row-1][column] + num[row][column+1] ) / 2 + 0.5; } else if(row==19&&column==29) { if( (num[row][column] - num[row-1][column])>1 && (num[row][column] - num[row][column-1])>1 ) num[row][column] = ( num[row-1][column] + num[row][column-1] ) / 2 + 0.5; } else if(row==0) { if( (num[row][column] - num[row][column-1])>1 && (num[row][column] - num[row+1][column])>1 && (num[row][column] - num[row][column+1])>1 ) num[row][column] = ( num[row][column-1] + num[row+1][column] + num[row][column+1]) / 3 + 0.5; } else if(column==0) { if( (num[row][column] - num[row-1][column])>1 && (num[row][column] - num[row+1][column])>1 && (num[row][column] - num[row][column+1])>1 ) num[row][column] = ( num[row-1][column] + num[row+1][column] + num[row][column+1]) / 3 + 0.5; } else if(row==19) { if( (num[row][column] - num[row-1][column])>1 && (num[row][column] - num[row][column-1])>1 && (num[row][column] - num[row][column+1])>1 ) num[row][column] = ( num[row-1][column] + num[row][column-1] + num[row][column+1]) / 3 + 0.5; } else if(column==29) { if( (num[row][column] - num[row-1][column])>1 && (num[row][column] - num[row+1][column])>1 && (num[row][column] - num[row][column-1])>1 ) num[row][column] = ( num[row-1][column] + num[row+1][column] + num[row][column-1]) / 3 + 0.5; } else { if( (num[row][column] - num[row-1][column])>1 && (num[row][column] - num[row+1][column])>1 && (num[row][column] - num[row][column-1])>1 && (num[row][column] - num[row][column+1])>1 ) num[row][column] = ( num[row-1][column] + num[row+1][column] + num[row][column-1]) + num[row][column+1]/ 4 + 0.5; } } for (row=0; row<20; row++) { for (column=0; column<30; column++) photo[row][column] = table[ num[row][column] ]; photo[row][column] = '\0'; } for (row=0; row<20; row++) puts(photo[row]); printf("input the name of destination file:"); gets(name); if ( ( fp=fopen(name,"w") ) == NULL ) { printf("Can't open %s",name); exit(1); } for (row=0; row<20; row++) fprintf(fp,"%s\n",photo[row]); return 0; }