Single class NMS implemented in Numpy.
(boxes, scores, nms_thr)
| 15 | |
| 16 | |
| 17 | def nms(boxes, scores, nms_thr): |
| 18 | """Single class NMS implemented in Numpy.""" |
| 19 | x1 = boxes[:, 0] |
| 20 | y1 = boxes[:, 1] |
| 21 | x2 = boxes[:, 2] |
| 22 | y2 = boxes[:, 3] |
| 23 | |
| 24 | areas = (x2 - x1 + 1) * (y2 - y1 + 1) |
| 25 | order = scores.argsort()[::-1] |
| 26 | |
| 27 | keep = [] |
| 28 | while order.size > 0: |
| 29 | i = order[0] |
| 30 | keep.append(i) |
| 31 | xx1 = np.maximum(x1[i], x1[order[1:]]) |
| 32 | yy1 = np.maximum(y1[i], y1[order[1:]]) |
| 33 | xx2 = np.minimum(x2[i], x2[order[1:]]) |
| 34 | yy2 = np.minimum(y2[i], y2[order[1:]]) |
| 35 | |
| 36 | w = np.maximum(0.0, xx2 - xx1 + 1) |
| 37 | h = np.maximum(0.0, yy2 - yy1 + 1) |
| 38 | inter = w * h |
| 39 | ovr = inter / (areas[i] + areas[order[1:]] - inter) |
| 40 | |
| 41 | inds = np.where(ovr <= nms_thr)[0] |
| 42 | order = order[inds + 1] |
| 43 | |
| 44 | return keep |
| 45 | |
| 46 | |
| 47 | def multiclass_nms(boxes, scores, nms_thr, score_thr): |