Added ability to use letter_box resizing in darknet.py sample

build/darknet/x64/darknet.py

@@ -202,6 +202,10 @@ predict_image = lib.network_predict_image
 predict_image.argtypes = [c_void_p, IMAGE]
 predict_image.restype = POINTER(c_float)
 
+predict_image_letterbox = lib.network_predict_image_letterbox
+predict_image_letterbox.argtypes = [c_void_p, IMAGE]
+predict_image_letterbox.restype = POINTER(c_float)
+
 def array_to_image(arr):
     import numpy as np
     # need to return old values to avoid python freeing memory
@@ -251,9 +255,12 @@ def detect_image(net, meta, im, thresh=.5, hier_thresh=.5, nms=.45, debug= False
     pnum = pointer(num)
     if debug: print("Assigned pnum")
     predict_image(net, im)
+    letter_box = 0
+    #predict_image_letterbox(net, im)
+    #letter_box = 1
     if debug: print("did prediction")
-    #dets = get_network_boxes(net, custom_image_bgr.shape[1], custom_image_bgr.shape[0], thresh, hier_thresh, None, 0, pnum, 0) # OpenCV
+    #dets = get_network_boxes(net, custom_image_bgr.shape[1], custom_image_bgr.shape[0], thresh, hier_thresh, None, 0, pnum, letter_box) # OpenCV
-    dets = get_network_boxes(net, im.w, im.h, thresh, hier_thresh, None, 0, pnum, 0)
+    dets = get_network_boxes(net, im.w, im.h, thresh, hier_thresh, None, 0, pnum, letter_box)
     if debug: print("Got dets")
     num = pnum[0]
     if debug: print("got zeroth index of pnum")

build/darknet/x64/darknet_python.cmd

@@ -4,7 +4,7 @@ rem C:\Python27\Scripts\pip install scikit-image
 rem C:\Python27\Scripts\pip install scipy
 rem C:\Python27\Scripts\pip install opencv-python
 
-C:\Python27\python.exe darknet.py
+rem C:\Python27\python.exe darknet.py
 
 
 
@@ -14,6 +14,6 @@ rem C:\Users\Alex\AppData\Local\Programs\Python\Python36\Scripts\pip install sci
 rem C:\Users\Alex\AppData\Local\Programs\Python\Python36\Scripts\pip install scipy
 rem C:\Users\Alex\AppData\Local\Programs\Python\Python36\Scripts\pip install opencv-python
 
-rem C:\Users\Alex\AppData\Local\Programs\Python\Python36\python.exe darknet.py
+C:\Users\Alex\AppData\Local\Programs\Python\Python36\python.exe darknet.py
 
 pause

darknet.py

@@ -202,6 +202,10 @@ predict_image = lib.network_predict_image
 predict_image.argtypes = [c_void_p, IMAGE]
 predict_image.restype = POINTER(c_float)
 
+predict_image_letterbox = lib.network_predict_image_letterbox
+predict_image_letterbox.argtypes = [c_void_p, IMAGE]
+predict_image_letterbox.restype = POINTER(c_float)
+
 def array_to_image(arr):
     import numpy as np
     # need to return old values to avoid python freeing memory
@@ -251,9 +255,12 @@ def detect_image(net, meta, im, thresh=.5, hier_thresh=.5, nms=.45, debug= False
     pnum = pointer(num)
     if debug: print("Assigned pnum")
     predict_image(net, im)
+    letter_box = 0
+    #predict_image_letterbox(net, im)
+    #letter_box = 1
     if debug: print("did prediction")
-    #dets = get_network_boxes(net, custom_image_bgr.shape[1], custom_image_bgr.shape[0], thresh, hier_thresh, None, 0, pnum, 0) # OpenCV
+    #dets = get_network_boxes(net, custom_image_bgr.shape[1], custom_image_bgr.shape[0], thresh, hier_thresh, None, 0, pnum, letter_box) # OpenCV
-    dets = get_network_boxes(net, im.w, im.h, thresh, hier_thresh, None, 0, pnum, 0)
+    dets = get_network_boxes(net, im.w, im.h, thresh, hier_thresh, None, 0, pnum, letter_box)
     if debug: print("Got dets")
     num = pnum[0]
     if debug: print("got zeroth index of pnum")

include/darknet.h

@@ -833,6 +833,7 @@ LIB_API layer* get_network_layer(network* net, int i);
 LIB_API detection *make_network_boxes(network *net, float thresh, int *num);
 LIB_API void reset_rnn(network *net);
 LIB_API float *network_predict_image(network *net, image im);
+LIB_API float *network_predict_image_letterbox(network *net, image im);
 LIB_API float validate_detector_map(char *datacfg, char *cfgfile, char *weightfile, float thresh_calc_avg_iou, const float iou_thresh, const int map_points, int letter_box, network *existing_net);
 LIB_API void train_detector(char *datacfg, char *cfgfile, char *weightfile, int *gpus, int ngpus, int clear, int dont_show, int calc_map, int mjpeg_port, int show_imgs);
 LIB_API void test_detector(char *datacfg, char *cfgfile, char *weightfile, char *filename, float thresh,

src/network.c

@@ -842,6 +842,24 @@ float *network_predict_image(network *net, image im)
     return p;
 }
 
+float *network_predict_image_letterbox(network *net, image im)
+{
+    //image imr = letterbox_image(im, net->w, net->h);
+    float *p;
+    if (net->batch != 1) set_batch_network(net, 1);
+    if (im.w == net->w && im.h == net->h) {
+        // Input image is the same size as our net, predict on that image
+        p = network_predict(*net, im.data);
+    }
+    else {
+        // Need to resize image to the desired size for the net
+        image imr = letterbox_image(im, net->w, net->h);
+        p = network_predict(*net, imr.data);
+        free_image(imr);
+    }
+    return p;
+}
+
 int network_width(network *net) { return net->w; }
 int network_height(network *net) { return net->h; }