/*Function:int prepareFeatsData(string samples_path, string outfile, char* class_samples, uchar* char_class, int nclass, string extens)
Features：
對指定的樣本（數字和字母）的路徑下的各個指定的樣本檔案進行特徵提取，
連同類編號依次存入outfile指定檔案中。
Attention:
注意_finddata_t結構體和_findfirst函式的用法
in-parameter:
samples_path：所有樣本歸屬的資料夾
outfile：提取特徵後寫入的檔案
class_samples：各個樣本的資料夾標記
char_class：各樣本的類別標記
nclass：有多少類樣本
extens：樣本檔案的字尾副檔名（例如："*.png"）
out-parameter:
Return    : 處理的樣本總數
Author: Mengjia  Date：2017-1-5 16:05:47
 
*/
int prepareFeatsData(string samples_path, string outfile, char* class_samples, uchar* char_class, int nclass, string extens)
{
    int itatol = 0;
    FILE   *fp;
    fp = fopen(outfile.c_str(), "w+"); //train_samples\\train_lbp.txt
    long hFile;//int nn=0;
    for (int nsamp = 0; nsamp < nclass; nsamp++)
    {
        
 
string cur_folder = samples_path;
        cur_folder += '\\';
        cur_folder += class_samples[nsamp];//樣本的資料夾標記
        cur_folder += '\\';
        string findfile = cur_folder;
        findfile += extens;//所要尋找的檔案格式全路徑

        struct _finddata_t img_file;

        if ((hFile = _findfirst(findfile.c_str(), &img_file)) == -1L
 
)//"rawdata/*.png"
        {
            printf("no %s files in directory :%s\n", extens.c_str(), findfile.c_str());
            //printf(findfile.c_str());
        }
        do
        {
            string filename = cur_folder;
            filename += img_file.name;
            IplImage* pImg = cvLoadImage(filename.c_str(), CV_LOAD_IMAGE_UNCHANGED);
            if (pImg)
            {    //nn++;
                itatol++;
                IplImage* pBImg = alignmentImg(pImg);
                IplImage* standarImg = sizeNormalization(pBImg, 32, 64);
                int scale_flag = SCALE_LBP_FEATURES;
                CvMat* lbp_feats = LBP_features(standarImg, 8, 8, 4, scale_flag);

                if (scale_flag == SCALE_LBP_FEATURES)
                {
                    double*pData = (double*)(lbp_feats->data.db);
                    fprintf(fp, "%d ", char_class[nsamp]); //寫入樣本類別 

                    for (int i = 0; i < lbp_feats->cols * lbp_feats->rows; i++)
                    {
                        if (pData[i] != 0.)
                            fprintf(fp, "%d%s%g ", i + 1, ":", pData[i]);   //按格式寫入特徵
                    }

                    fprintf(fp, "\t\n");
                }
                else
                {
                    uchar*pData = (uchar*)(lbp_feats->data.ptr);
                    fprintf(fp, "%d ", char_class[nsamp]); //寫入樣本類別 

                    for (int i = 0; i < lbp_feats->cols * lbp_feats->rows; i++)
                    {
                        if (pData[i] != 0.)
                            fprintf(fp, "%d%s%d ", i + 1, ":", pData[i]);   //按格式寫入特徵
                    }

                    fprintf(fp, "\t\n");
                }

                cvReleaseMat(&lbp_feats);
                cvReleaseImage(&pBImg);
                cvReleaseImage(&standarImg);
                cvReleaseImage(&pImg);
            }
        } while (_findnext(hFile, &img_file) == 0);
        _findclose(hFile);
    }
    fclose(fp);
    printf("total samples = %d\n", itatol);
    return itatol;
}