Add support to ignore first 50 iterations in calculating the remaining training time.

For first 50 iterations chart will display 'nan hours' as remaining training time.

src/detector.c

@@ -308,11 +308,13 @@ void train_detector(char *datacfg, char *cfgfile, char *weightfile, int *gpus, i
         time_remaining[i%1000] = (net.max_batches - i)*(end - start) / 60 / 60;
         tmp = 0.0;
         int j, count = 0;
-        for (j = 0; j < 1000; ++j){
+        if (i > 50){
+            for (j = 0; j < 1000; ++j){
             if (time_remaining[j] != 0){
                 tmp += time_remaining[j];
                 count++;
             }
+            }
         }
         draw_train_loss(windows_name, img, img_size, avg_loss, max_img_loss, i, net.max_batches, mean_average_precision, draw_precision, "mAP%", dont_show, mjpeg_port, tmp/count);
         start = what_time_is_it_now();

src/image_opencv.cpp

@@ -1104,7 +1104,7 @@ extern "C" void draw_train_loss(char *windows_name, mat_cv* img_src, int img_siz
             old_precision = precision;
             iteration_old = current_batch;
         }
-        sprintf(char_buff, "current avg loss = %2.4f    iteration = %d    approx. time remaining = %2.2f hours", avg_loss, current_batch, time_remaining);
+        sprintf(char_buff, "current avg loss = %2.4f    iteration = %d    approx. time left = %2.2f hours", avg_loss, current_batch, time_remaining);
         pt1.x = 15, pt1.y = draw_size + 18;
         pt2.x = pt1.x + 800, pt2.y = pt1.y + 20;
         cv::rectangle(img, pt1, pt2, CV_RGB(255, 255, 255), CV_FILLED, 8, 0);