Could you please help me with the soft-nms
jyning12 opened this issue · 2 comments
jyning12 commented
In your kaggle post, I see you used the soft-nms, I have difficuty with it, I can't find your soft-nms code in this git.
ZFTurbo commented
I used this function. I found it somewhere on github, can't remember where exactly
def cpu_soft_nms(boxes, sigma=0.75, Nt=0.5, threshold=0.01, method=2):
N = boxes.shape[0]
pos = 0
maxscore = 0
maxpos = 0
for i in range(N):
maxscore = boxes[i, 4]
maxpos = i
tx1 = boxes[i, 0]
ty1 = boxes[i, 1]
tx2 = boxes[i, 2]
ty2 = boxes[i, 3]
ts = boxes[i, 4]
pos = i + 1
# get max box
while pos < N:
if maxscore < boxes[pos, 4]:
maxscore = boxes[pos, 4]
maxpos = pos
pos = pos + 1
# add max box as a detection
boxes[i, 0] = boxes[maxpos, 0]
boxes[i, 1] = boxes[maxpos, 1]
boxes[i, 2] = boxes[maxpos, 2]
boxes[i, 3] = boxes[maxpos, 3]
boxes[i, 4] = boxes[maxpos, 4]
# swap ith box with position of max box
boxes[maxpos, 0] = tx1
boxes[maxpos, 1] = ty1
boxes[maxpos, 2] = tx2
boxes[maxpos, 3] = ty2
boxes[maxpos, 4] = ts
tx1 = boxes[i, 0]
ty1 = boxes[i, 1]
tx2 = boxes[i, 2]
ty2 = boxes[i, 3]
ts = boxes[i, 4]
pos = i + 1
# NMS iterations, note that N changes if detection boxes fall below threshold
while pos < N:
x1 = boxes[pos, 0]
y1 = boxes[pos, 1]
x2 = boxes[pos, 2]
y2 = boxes[pos, 3]
s = boxes[pos, 4]
area = (x2 - x1 + 1) * (y2 - y1 + 1)
iw = (min(tx2, x2) - max(tx1, x1) + 1)
if iw > 0:
ih = (min(ty2, y2) - max(ty1, y1) + 1)
if ih > 0:
ua = float((tx2 - tx1 + 1) * (ty2 - ty1 + 1) + area - iw * ih)
ov = iw * ih / ua # iou between max box and detection box
if method == 1: # linear
if ov > Nt:
weight = 1 - ov
else:
weight = 1
elif method == 2: # gaussian
weight = np.exp(-(ov * ov) / sigma)
else: # original NMS
if ov > Nt:
weight = 0
else:
weight = 1
boxes[pos, 4] = weight * boxes[pos, 4]
# if box score falls below threshold, discard the box by swapping with last box
# update N
if boxes[pos, 4] < threshold:
boxes[pos, 0] = boxes[N - 1, 0]
boxes[pos, 1] = boxes[N - 1, 1]
boxes[pos, 2] = boxes[N - 1, 2]
boxes[pos, 3] = boxes[N - 1, 3]
boxes[pos, 4] = boxes[N - 1, 4]
N = N - 1
pos = pos - 1
pos = pos + 1
keep = [i for i in range(N)]
return keep
jyning12 commented
thank you very much, best regards for you!