first commit

ssd/data/transforms/target_transform.py

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+import numpy as np
+import torch
+
+from ssd.utils import box_utils
+
+
+class SSDTargetTransform:
+    def __init__(self, center_form_priors, center_variance, size_variance, iou_threshold):
+        self.center_form_priors = center_form_priors
+        self.corner_form_priors = box_utils.center_form_to_corner_form(center_form_priors)
+        self.center_variance = center_variance
+        self.size_variance = size_variance
+        self.iou_threshold = iou_threshold
+
+    def __call__(self, gt_boxes, gt_labels):
+        if type(gt_boxes) is np.ndarray:
+            gt_boxes = torch.from_numpy(gt_boxes)
+        if type(gt_labels) is np.ndarray:
+            gt_labels = torch.from_numpy(gt_labels)
+        boxes, labels = box_utils.assign_priors(gt_boxes, gt_labels,
+                                                self.corner_form_priors, self.iou_threshold)
+        boxes = box_utils.corner_form_to_center_form(boxes)
+        locations = box_utils.convert_boxes_to_locations(boxes, self.center_form_priors, self.center_variance, self.size_variance)
+       
+        return locations, labels