Change the default value of topK (#271)

* Change the default value of topK

* Change several more default values

demo.cpp

@@ -31,7 +31,7 @@ private:
     Mat anchors;
 
 public:
-    MPPersonDet(string modPath, float nmsThresh = 0.5, float scoreThresh = 0.3, int tok = 1, dnn::Backend bId = DNN_BACKEND_DEFAULT, dnn::Target tId = DNN_TARGET_CPU) :
+    MPPersonDet(string modPath, float nmsThresh = 0.3, float scoreThresh = 0.5, int tok = 5000, dnn::Backend bId = DNN_BACKEND_DEFAULT, dnn::Target tId = DNN_TARGET_CPU) :
         modelPath(modPath), nmsThreshold(nmsThresh),
         scoreThreshold(scoreThresh), topK(tok),
         backendId(bId), targetId(tId)

demo.py

@@ -36,7 +36,7 @@ parser.add_argument('--score_threshold', type=float, default=0.5,
                     help='Usage:  Set the minimum needed confidence for the model to identify a person, defaults to 0.5. Smaller values may result in faster detection, but will limit accuracy. Filter out persons of confidence < conf_threshold.')
 parser.add_argument('--nms_threshold', type=float, default=0.3,
                     help='Usage: Suppress bounding boxes of iou >= nms_threshold. Default = 0.3.')
-parser.add_argument('--top_k', type=int, default=1,
+parser.add_argument('--top_k', type=int, default=5000,
                     help='Usage: Keep top_k bounding boxes before NMS.')
 parser.add_argument('--save', '-s', action='store_true',
                     help='Usage: Specify to save file with results (i.e. bounding box, confidence level). Invalid in case of camera input.')

mp_persondet.py

@@ -2,7 +2,7 @@ import numpy as np
 import cv2 as cv
 
 class MPPersonDet:
-    def __init__(self, modelPath, nmsThreshold=0.3, scoreThreshold=0.5, topK=1, backendId=0, targetId=0):
+    def __init__(self, modelPath, nmsThreshold=0.3, scoreThreshold=0.5, topK=5000, backendId=0, targetId=0):
         self.model_path = modelPath
         self.nms_threshold = nmsThreshold
         self.score_threshold = scoreThreshold