赞
踩
import tensorflow as tf def compute_overlaps(boxes1, boxes2): '''Computes IoU overlaps between two sets of boxes. boxes1, boxes2: [N, (y1, x1, y2, x2)]. ''' # 1. Tile boxes2 and repeate boxes1. This allows us to compare # every boxes1 against every boxes2 without loops. # TF doesn't have an equivalent to np.repeate() so simulate it # using tf.tile() and tf.reshape. b1 = tf.reshape(tf.tile(tf.expand_dims(boxes1, 1), [1, 1, tf.shape(boxes2)[0]]), [-1, 4]) b2 = tf.tile(boxes2, [tf.shape(boxes1)[0], 1]) # 2. Compute intersections b1_y1, b1_x1, b1_y2, b1_x2 = tf.split(b1, 4, axis=1) b2_y1, b2_x1, b2_y2, b2_x2 = tf.split(b2, 4, axis=1) y1 = tf.maximum(b1_y1, b2_y1) x1 = tf.maximum(b1_x1, b2_x1) y2 = tf.minimum(b1_y2, b2_y2) x2 = tf.minimum(b1_x2, b2_x2) intersection = tf.maximum(x2 - x1, 0) * tf.maximum(y2 - y1, 0) # 3. Compute unions b1_area = (b1_y2 - b1_y1) * (b1_x2 - b1_x1) b2_area = (b2_y2 - b2_y1) * (b2_x2 - b2_x1) union = b1_area + b2_area - intersection # 4. Compute IoU and reshape to [boxes1, boxes2] iou = intersection / union overlaps = tf.reshape(iou, [tf.shape(boxes1)[0], tf.shape(boxes2)[0]]) return overlaps
Copyright © 2003-2013 www.wpsshop.cn 版权所有,并保留所有权利。