C语言实现光谱角分类
时间: 2023-08-20 12:20:00 浏览: 50
以下是C语言实现光谱角分类的代码示例:
```c
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#define BANDS 224 //波段数
#define CLASSES 16 //类别数
#define PIXELS 10000 //像素数
float spectra[PIXELS][BANDS]; //存储像素光谱数据
int labels[PIXELS]; //存储像素标签
int main() {
FILE* fp;
float mean_spectra[CLASSES][BANDS]; //存储各类别的平均光谱向量
int train_samples[CLASSES]; //存储各类别的训练样本数量
int i, j, k;
//读取像素光谱数据和标签
fp = fopen("spectra.txt", "r");
for (i = 0; i < PIXELS; i++) {
for (j = 0; j < BANDS; j++) {
fscanf(fp, "%f", &spectra[i][j]);
}
fscanf(fp, "%d", &labels[i]);
}
fclose(fp);
//计算各类别的平均光谱向量
for (i = 0; i < CLASSES; i++) {
for (j = 0; j < BANDS; j++) {
mean_spectra[i][j] = 0.0;
}
train_samples[i] = 0;
}
for (i = 0; i < PIXELS; i++) {
for (j = 0; j < BANDS; j++) {
mean_spectra[labels[i]][j] += spectra[i][j];
}
train_samples[labels[i]]++;
}
for (i = 0; i < CLASSES; i++) {
for (j = 0; j < BANDS; j++) {
mean_spectra[i][j] /= train_samples[i];
}
}
//分类测试像素
int test_label;
float min_angle, angle;
for (i = 0; i < PIXELS; i++) {
min_angle = 180.0;
for (j = 0; j < CLASSES; j++) {
angle = 0.0;
for (k = 0; k < BANDS; k++) {
angle += mean_spectra[j][k] * spectra[i][k];
}
angle = acos(angle) * 180.0 / 3.1415926535; //计算夹角
if (angle < min_angle) {
min_angle = angle;
test_label = j;
}
}
printf("Pixel %d: true label = %d, predicted label = %d\n", i, labels[i], test_label);
}
return 0;
}
```
该代码实现了光谱角分类的基本流程,包括读取像素光谱数据和标签、计算各类别的平均光谱向量、分类测试像素等步骤。在测试像素时,对于每个像素,计算它与各个类别的平均光谱向量之间的夹角,选择夹角最小的类别作为其分类。