Module heyvi.model.yolov3.utils.utils
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from __future__ import division
import math
import time
from vipy.util import try_import
import torch
import torch.nn as nn
import torch.nn.functional as F
from torch.autograd import Variable
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.patches as patches
def to_cpu(tensor):
return tensor.detach().cpu()
def load_classes(path):
"""
Loads class labels at 'path'
"""
fp = open(path, "r")
names = fp.read().split("\n")[:-1]
return names
def weights_init_normal(m):
classname = m.__class__.__name__
if classname.find("Conv") != -1:
torch.nn.init.normal_(m.weight.data, 0.0, 0.02)
elif classname.find("BatchNorm2d") != -1:
torch.nn.init.normal_(m.weight.data, 1.0, 0.02)
torch.nn.init.constant_(m.bias.data, 0.0)
def rescale_boxes(boxes, current_dim, original_shape):
""" Rescales bounding boxes to the original shape """
orig_h, orig_w = original_shape
# The amount of padding that was added
pad_x = max(orig_h - orig_w, 0) * (current_dim / max(original_shape))
pad_y = max(orig_w - orig_h, 0) * (current_dim / max(original_shape))
# Image height and width after padding is removed
unpad_h = current_dim - pad_y
unpad_w = current_dim - pad_x
# Rescale bounding boxes to dimension of original image
boxes[:, 0] = ((boxes[:, 0] - pad_x // 2) / unpad_w) * orig_w
boxes[:, 1] = ((boxes[:, 1] - pad_y // 2) / unpad_h) * orig_h
boxes[:, 2] = ((boxes[:, 2] - pad_x // 2) / unpad_w) * orig_w
boxes[:, 3] = ((boxes[:, 3] - pad_y // 2) / unpad_h) * orig_h
return boxes
def xywh2xyxy(x):
y = x.new(x.shape)
y[..., 0] = x[..., 0] - x[..., 2] / 2
y[..., 1] = x[..., 1] - x[..., 3] / 2
y[..., 2] = x[..., 0] + x[..., 2] / 2
y[..., 3] = x[..., 1] + x[..., 3] / 2
return y
def ap_per_class(tp, conf, pred_cls, target_cls):
""" Compute the average precision, given the recall and precision curves.
Source: https://github.com/rafaelpadilla/Object-Detection-Metrics.
# Arguments
tp: True positives (list).
conf: Objectness value from 0-1 (list).
pred_cls: Predicted object classes (list).
target_cls: True object classes (list).
# Returns
The average precision as computed in py-faster-rcnn.
"""
try_import('tqdm', 'tqdm')
import tqdm
# Sort by objectness
i = np.argsort(-conf)
tp, conf, pred_cls = tp[i], conf[i], pred_cls[i]
# Find unique classes
unique_classes = np.unique(target_cls)
# Create Precision-Recall curve and compute AP for each class
ap, p, r = [], [], []
for c in tqdm.tqdm(unique_classes, desc="Computing AP"):
i = pred_cls == c
n_gt = (target_cls == c).sum() # Number of ground truth objects
n_p = i.sum() # Number of predicted objects
if n_p == 0 and n_gt == 0:
continue
elif n_p == 0 or n_gt == 0:
ap.append(0)
r.append(0)
p.append(0)
else:
# Accumulate FPs and TPs
fpc = (1 - tp[i]).cumsum()
tpc = (tp[i]).cumsum()
# Recall
recall_curve = tpc / (n_gt + 1e-16)
r.append(recall_curve[-1])
# Precision
precision_curve = tpc / (tpc + fpc)
p.append(precision_curve[-1])
# AP from recall-precision curve
ap.append(compute_ap(recall_curve, precision_curve))
# Compute F1 score (harmonic mean of precision and recall)
p, r, ap = np.array(p), np.array(r), np.array(ap)
f1 = 2 * p * r / (p + r + 1e-16)
return p, r, ap, f1, unique_classes.astype("int32")
def compute_ap(recall, precision):
""" Compute the average precision, given the recall and precision curves.
Code originally from https://github.com/rbgirshick/py-faster-rcnn.
# Arguments
recall: The recall curve (list).
precision: The precision curve (list).
# Returns
The average precision as computed in py-faster-rcnn.
"""
# correct AP calculation
# first append sentinel values at the end
mrec = np.concatenate(([0.0], recall, [1.0]))
mpre = np.concatenate(([0.0], precision, [0.0]))
# compute the precision envelope
for i in range(mpre.size - 1, 0, -1):
mpre[i - 1] = np.maximum(mpre[i - 1], mpre[i])
# to calculate area under PR curve, look for points
# where X axis (recall) changes value
i = np.where(mrec[1:] != mrec[:-1])[0]
# and sum (\Delta recall) * prec
ap = np.sum((mrec[i + 1] - mrec[i]) * mpre[i + 1])
return ap
def get_batch_statistics(outputs, targets, iou_threshold):
""" Compute true positives, predicted scores and predicted labels per sample """
batch_metrics = []
for sample_i in range(len(outputs)):
if outputs[sample_i] is None:
continue
output = outputs[sample_i]
pred_boxes = output[:, :4]
pred_scores = output[:, 4]
pred_labels = output[:, -1]
true_positives = np.zeros(pred_boxes.shape[0])
annotations = targets[targets[:, 0] == sample_i][:, 1:]
target_labels = annotations[:, 0] if len(annotations) else []
if len(annotations):
detected_boxes = []
target_boxes = annotations[:, 1:]
for pred_i, (pred_box, pred_label) in enumerate(zip(pred_boxes, pred_labels)):
# If targets are found break
if len(detected_boxes) == len(annotations):
break
# Ignore if label is not one of the target labels
if pred_label not in target_labels:
continue
iou, box_index = bbox_iou(pred_box.unsqueeze(0), target_boxes).max(0)
if iou >= iou_threshold and box_index not in detected_boxes:
true_positives[pred_i] = 1
detected_boxes += [box_index]
batch_metrics.append([true_positives, pred_scores, pred_labels])
return batch_metrics
def bbox_wh_iou(wh1, wh2):
wh2 = wh2.t()
w1, h1 = wh1[0], wh1[1]
w2, h2 = wh2[0], wh2[1]
inter_area = torch.min(w1, w2) * torch.min(h1, h2)
union_area = (w1 * h1 + 1e-16) + w2 * h2 - inter_area
return inter_area / union_area
def bbox_iou(box1, box2, x1y1x2y2=True):
"""
Returns the IoU of two bounding boxes
"""
if not x1y1x2y2:
# Transform from center and width to exact coordinates
b1_x1, b1_x2 = box1[:, 0] - box1[:, 2] / 2, box1[:, 0] + box1[:, 2] / 2
b1_y1, b1_y2 = box1[:, 1] - box1[:, 3] / 2, box1[:, 1] + box1[:, 3] / 2
b2_x1, b2_x2 = box2[:, 0] - box2[:, 2] / 2, box2[:, 0] + box2[:, 2] / 2
b2_y1, b2_y2 = box2[:, 1] - box2[:, 3] / 2, box2[:, 1] + box2[:, 3] / 2
else:
# Get the coordinates of bounding boxes
b1_x1, b1_y1, b1_x2, b1_y2 = box1[:, 0], box1[:, 1], box1[:, 2], box1[:, 3]
b2_x1, b2_y1, b2_x2, b2_y2 = box2[:, 0], box2[:, 1], box2[:, 2], box2[:, 3]
# get the corrdinates of the intersection rectangle
inter_rect_x1 = torch.max(b1_x1, b2_x1)
inter_rect_y1 = torch.max(b1_y1, b2_y1)
inter_rect_x2 = torch.min(b1_x2, b2_x2)
inter_rect_y2 = torch.min(b1_y2, b2_y2)
# Intersection area
inter_area = torch.clamp(inter_rect_x2 - inter_rect_x1 + 1, min=0) * torch.clamp(
inter_rect_y2 - inter_rect_y1 + 1, min=0
)
# Union Area
b1_area = (b1_x2 - b1_x1 + 1) * (b1_y2 - b1_y1 + 1)
b2_area = (b2_x2 - b2_x1 + 1) * (b2_y2 - b2_y1 + 1)
iou = inter_area / (b1_area + b2_area - inter_area + 1e-16)
return iou
def non_max_suppression(prediction, conf_thres=0.5, nms_thres=0.4):
"""
Removes detections with lower object confidence score than 'conf_thres' and performs
Non-Maximum Suppression to further filter detections.
Returns detections with shape:
(x1, y1, x2, y2, object_conf, class_score, class_pred)
"""
# From (center x, center y, width, height) to (x1, y1, x2, y2)
prediction[..., :4] = xywh2xyxy(prediction[..., :4])
output = [None for _ in range(len(prediction))]
for image_i, image_pred in enumerate(prediction):
# Filter out confidence scores below threshold
image_pred = image_pred[image_pred[:, 4] >= conf_thres]
# If none are remaining => process next image
if not image_pred.size(0):
continue
# Object confidence times class confidence
score = image_pred[:, 4] * image_pred[:, 5:].max(1)[0]
# Sort by it
image_pred = image_pred[(-score).argsort()]
class_confs, class_preds = image_pred[:, 5:].max(1, keepdim=True)
detections = torch.cat((image_pred[:, :5], class_confs.float(), class_preds.float()), 1)
# Perform non-maximum suppression
keep_boxes = []
while detections.size(0):
large_overlap = bbox_iou(detections[0, :4].unsqueeze(0), detections[:, :4]) > nms_thres
label_match = detections[0, -1] == detections[:, -1]
# Indices of boxes with lower confidence scores, large IOUs and matching labels
invalid = large_overlap & label_match
weights = detections[invalid, 4:5]
# Merge overlapping bboxes by order of confidence
detections[0, :4] = (weights * detections[invalid, :4]).sum(0) / weights.sum()
keep_boxes += [detections[0]]
detections = detections[~invalid]
if keep_boxes:
output[image_i] = torch.stack(keep_boxes)
return output
def build_targets(pred_boxes, pred_cls, target, anchors, ignore_thres):
ByteTensor = torch.cuda.ByteTensor if pred_boxes.is_cuda else torch.ByteTensor
FloatTensor = torch.cuda.FloatTensor if pred_boxes.is_cuda else torch.FloatTensor
nB = pred_boxes.size(0)
nA = pred_boxes.size(1)
nC = pred_cls.size(-1)
nG = pred_boxes.size(2)
# Output tensors
obj_mask = ByteTensor(nB, nA, nG, nG).fill_(0)
noobj_mask = ByteTensor(nB, nA, nG, nG).fill_(1)
class_mask = FloatTensor(nB, nA, nG, nG).fill_(0)
iou_scores = FloatTensor(nB, nA, nG, nG).fill_(0)
tx = FloatTensor(nB, nA, nG, nG).fill_(0)
ty = FloatTensor(nB, nA, nG, nG).fill_(0)
tw = FloatTensor(nB, nA, nG, nG).fill_(0)
th = FloatTensor(nB, nA, nG, nG).fill_(0)
tcls = FloatTensor(nB, nA, nG, nG, nC).fill_(0)
# Convert to position relative to box
target_boxes = target[:, 2:6] * nG
gxy = target_boxes[:, :2]
gwh = target_boxes[:, 2:]
# Get anchors with best iou
ious = torch.stack([bbox_wh_iou(anchor, gwh) for anchor in anchors])
best_ious, best_n = ious.max(0)
# Separate target values
b, target_labels = target[:, :2].long().t()
gx, gy = gxy.t()
gw, gh = gwh.t()
gi, gj = gxy.long().t()
# Set masks
obj_mask[b, best_n, gj, gi] = 1
noobj_mask[b, best_n, gj, gi] = 0
# Set noobj mask to zero where iou exceeds ignore threshold
for i, anchor_ious in enumerate(ious.t()):
noobj_mask[b[i], anchor_ious > ignore_thres, gj[i], gi[i]] = 0
# Coordinates
tx[b, best_n, gj, gi] = gx - gx.floor()
ty[b, best_n, gj, gi] = gy - gy.floor()
# Width and height
tw[b, best_n, gj, gi] = torch.log(gw / anchors[best_n][:, 0] + 1e-16)
th[b, best_n, gj, gi] = torch.log(gh / anchors[best_n][:, 1] + 1e-16)
# One-hot encoding of label
tcls[b, best_n, gj, gi, target_labels] = 1
# Compute label correctness and iou at best anchor
class_mask[b, best_n, gj, gi] = (pred_cls[b, best_n, gj, gi].argmax(-1) == target_labels).float()
iou_scores[b, best_n, gj, gi] = bbox_iou(pred_boxes[b, best_n, gj, gi], target_boxes, x1y1x2y2=False)
tconf = obj_mask.float()
return iou_scores, class_mask, obj_mask, noobj_mask, tx, ty, tw, th, tcls, tconf
Functions
def ap_per_class(tp, conf, pred_cls, target_cls)
-
Compute the average precision, given the recall and precision curves. Source: https://github.com/rafaelpadilla/Object-Detection-Metrics.
Arguments
tp: True positives (list). conf: Objectness value from 0-1 (list). pred_cls: Predicted object classes (list). target_cls: True object classes (list).
Returns
The average precision as computed in py-faster-rcnn.
Expand source code Browse git
def ap_per_class(tp, conf, pred_cls, target_cls): """ Compute the average precision, given the recall and precision curves. Source: https://github.com/rafaelpadilla/Object-Detection-Metrics. # Arguments tp: True positives (list). conf: Objectness value from 0-1 (list). pred_cls: Predicted object classes (list). target_cls: True object classes (list). # Returns The average precision as computed in py-faster-rcnn. """ try_import('tqdm', 'tqdm') import tqdm # Sort by objectness i = np.argsort(-conf) tp, conf, pred_cls = tp[i], conf[i], pred_cls[i] # Find unique classes unique_classes = np.unique(target_cls) # Create Precision-Recall curve and compute AP for each class ap, p, r = [], [], [] for c in tqdm.tqdm(unique_classes, desc="Computing AP"): i = pred_cls == c n_gt = (target_cls == c).sum() # Number of ground truth objects n_p = i.sum() # Number of predicted objects if n_p == 0 and n_gt == 0: continue elif n_p == 0 or n_gt == 0: ap.append(0) r.append(0) p.append(0) else: # Accumulate FPs and TPs fpc = (1 - tp[i]).cumsum() tpc = (tp[i]).cumsum() # Recall recall_curve = tpc / (n_gt + 1e-16) r.append(recall_curve[-1]) # Precision precision_curve = tpc / (tpc + fpc) p.append(precision_curve[-1]) # AP from recall-precision curve ap.append(compute_ap(recall_curve, precision_curve)) # Compute F1 score (harmonic mean of precision and recall) p, r, ap = np.array(p), np.array(r), np.array(ap) f1 = 2 * p * r / (p + r + 1e-16) return p, r, ap, f1, unique_classes.astype("int32")
def bbox_iou(box1, box2, x1y1x2y2=True)
-
Returns the IoU of two bounding boxes
Expand source code Browse git
def bbox_iou(box1, box2, x1y1x2y2=True): """ Returns the IoU of two bounding boxes """ if not x1y1x2y2: # Transform from center and width to exact coordinates b1_x1, b1_x2 = box1[:, 0] - box1[:, 2] / 2, box1[:, 0] + box1[:, 2] / 2 b1_y1, b1_y2 = box1[:, 1] - box1[:, 3] / 2, box1[:, 1] + box1[:, 3] / 2 b2_x1, b2_x2 = box2[:, 0] - box2[:, 2] / 2, box2[:, 0] + box2[:, 2] / 2 b2_y1, b2_y2 = box2[:, 1] - box2[:, 3] / 2, box2[:, 1] + box2[:, 3] / 2 else: # Get the coordinates of bounding boxes b1_x1, b1_y1, b1_x2, b1_y2 = box1[:, 0], box1[:, 1], box1[:, 2], box1[:, 3] b2_x1, b2_y1, b2_x2, b2_y2 = box2[:, 0], box2[:, 1], box2[:, 2], box2[:, 3] # get the corrdinates of the intersection rectangle inter_rect_x1 = torch.max(b1_x1, b2_x1) inter_rect_y1 = torch.max(b1_y1, b2_y1) inter_rect_x2 = torch.min(b1_x2, b2_x2) inter_rect_y2 = torch.min(b1_y2, b2_y2) # Intersection area inter_area = torch.clamp(inter_rect_x2 - inter_rect_x1 + 1, min=0) * torch.clamp( inter_rect_y2 - inter_rect_y1 + 1, min=0 ) # Union Area b1_area = (b1_x2 - b1_x1 + 1) * (b1_y2 - b1_y1 + 1) b2_area = (b2_x2 - b2_x1 + 1) * (b2_y2 - b2_y1 + 1) iou = inter_area / (b1_area + b2_area - inter_area + 1e-16) return iou
def bbox_wh_iou(wh1, wh2)
-
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def bbox_wh_iou(wh1, wh2): wh2 = wh2.t() w1, h1 = wh1[0], wh1[1] w2, h2 = wh2[0], wh2[1] inter_area = torch.min(w1, w2) * torch.min(h1, h2) union_area = (w1 * h1 + 1e-16) + w2 * h2 - inter_area return inter_area / union_area
def build_targets(pred_boxes, pred_cls, target, anchors, ignore_thres)
-
Expand source code Browse git
def build_targets(pred_boxes, pred_cls, target, anchors, ignore_thres): ByteTensor = torch.cuda.ByteTensor if pred_boxes.is_cuda else torch.ByteTensor FloatTensor = torch.cuda.FloatTensor if pred_boxes.is_cuda else torch.FloatTensor nB = pred_boxes.size(0) nA = pred_boxes.size(1) nC = pred_cls.size(-1) nG = pred_boxes.size(2) # Output tensors obj_mask = ByteTensor(nB, nA, nG, nG).fill_(0) noobj_mask = ByteTensor(nB, nA, nG, nG).fill_(1) class_mask = FloatTensor(nB, nA, nG, nG).fill_(0) iou_scores = FloatTensor(nB, nA, nG, nG).fill_(0) tx = FloatTensor(nB, nA, nG, nG).fill_(0) ty = FloatTensor(nB, nA, nG, nG).fill_(0) tw = FloatTensor(nB, nA, nG, nG).fill_(0) th = FloatTensor(nB, nA, nG, nG).fill_(0) tcls = FloatTensor(nB, nA, nG, nG, nC).fill_(0) # Convert to position relative to box target_boxes = target[:, 2:6] * nG gxy = target_boxes[:, :2] gwh = target_boxes[:, 2:] # Get anchors with best iou ious = torch.stack([bbox_wh_iou(anchor, gwh) for anchor in anchors]) best_ious, best_n = ious.max(0) # Separate target values b, target_labels = target[:, :2].long().t() gx, gy = gxy.t() gw, gh = gwh.t() gi, gj = gxy.long().t() # Set masks obj_mask[b, best_n, gj, gi] = 1 noobj_mask[b, best_n, gj, gi] = 0 # Set noobj mask to zero where iou exceeds ignore threshold for i, anchor_ious in enumerate(ious.t()): noobj_mask[b[i], anchor_ious > ignore_thres, gj[i], gi[i]] = 0 # Coordinates tx[b, best_n, gj, gi] = gx - gx.floor() ty[b, best_n, gj, gi] = gy - gy.floor() # Width and height tw[b, best_n, gj, gi] = torch.log(gw / anchors[best_n][:, 0] + 1e-16) th[b, best_n, gj, gi] = torch.log(gh / anchors[best_n][:, 1] + 1e-16) # One-hot encoding of label tcls[b, best_n, gj, gi, target_labels] = 1 # Compute label correctness and iou at best anchor class_mask[b, best_n, gj, gi] = (pred_cls[b, best_n, gj, gi].argmax(-1) == target_labels).float() iou_scores[b, best_n, gj, gi] = bbox_iou(pred_boxes[b, best_n, gj, gi], target_boxes, x1y1x2y2=False) tconf = obj_mask.float() return iou_scores, class_mask, obj_mask, noobj_mask, tx, ty, tw, th, tcls, tconf
def compute_ap(recall, precision)
-
Compute the average precision, given the recall and precision curves. Code originally from https://github.com/rbgirshick/py-faster-rcnn.
Arguments
recall: The recall curve (list). precision: The precision curve (list).
Returns
The average precision as computed in py-faster-rcnn.
Expand source code Browse git
def compute_ap(recall, precision): """ Compute the average precision, given the recall and precision curves. Code originally from https://github.com/rbgirshick/py-faster-rcnn. # Arguments recall: The recall curve (list). precision: The precision curve (list). # Returns The average precision as computed in py-faster-rcnn. """ # correct AP calculation # first append sentinel values at the end mrec = np.concatenate(([0.0], recall, [1.0])) mpre = np.concatenate(([0.0], precision, [0.0])) # compute the precision envelope for i in range(mpre.size - 1, 0, -1): mpre[i - 1] = np.maximum(mpre[i - 1], mpre[i]) # to calculate area under PR curve, look for points # where X axis (recall) changes value i = np.where(mrec[1:] != mrec[:-1])[0] # and sum (\Delta recall) * prec ap = np.sum((mrec[i + 1] - mrec[i]) * mpre[i + 1]) return ap
def get_batch_statistics(outputs, targets, iou_threshold)
-
Compute true positives, predicted scores and predicted labels per sample
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def get_batch_statistics(outputs, targets, iou_threshold): """ Compute true positives, predicted scores and predicted labels per sample """ batch_metrics = [] for sample_i in range(len(outputs)): if outputs[sample_i] is None: continue output = outputs[sample_i] pred_boxes = output[:, :4] pred_scores = output[:, 4] pred_labels = output[:, -1] true_positives = np.zeros(pred_boxes.shape[0]) annotations = targets[targets[:, 0] == sample_i][:, 1:] target_labels = annotations[:, 0] if len(annotations) else [] if len(annotations): detected_boxes = [] target_boxes = annotations[:, 1:] for pred_i, (pred_box, pred_label) in enumerate(zip(pred_boxes, pred_labels)): # If targets are found break if len(detected_boxes) == len(annotations): break # Ignore if label is not one of the target labels if pred_label not in target_labels: continue iou, box_index = bbox_iou(pred_box.unsqueeze(0), target_boxes).max(0) if iou >= iou_threshold and box_index not in detected_boxes: true_positives[pred_i] = 1 detected_boxes += [box_index] batch_metrics.append([true_positives, pred_scores, pred_labels]) return batch_metrics
def load_classes(path)
-
Loads class labels at 'path'
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def load_classes(path): """ Loads class labels at 'path' """ fp = open(path, "r") names = fp.read().split("\n")[:-1] return names
def non_max_suppression(prediction, conf_thres=0.5, nms_thres=0.4)
-
Removes detections with lower object confidence score than 'conf_thres' and performs Non-Maximum Suppression to further filter detections. Returns detections with shape: (x1, y1, x2, y2, object_conf, class_score, class_pred)
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def non_max_suppression(prediction, conf_thres=0.5, nms_thres=0.4): """ Removes detections with lower object confidence score than 'conf_thres' and performs Non-Maximum Suppression to further filter detections. Returns detections with shape: (x1, y1, x2, y2, object_conf, class_score, class_pred) """ # From (center x, center y, width, height) to (x1, y1, x2, y2) prediction[..., :4] = xywh2xyxy(prediction[..., :4]) output = [None for _ in range(len(prediction))] for image_i, image_pred in enumerate(prediction): # Filter out confidence scores below threshold image_pred = image_pred[image_pred[:, 4] >= conf_thres] # If none are remaining => process next image if not image_pred.size(0): continue # Object confidence times class confidence score = image_pred[:, 4] * image_pred[:, 5:].max(1)[0] # Sort by it image_pred = image_pred[(-score).argsort()] class_confs, class_preds = image_pred[:, 5:].max(1, keepdim=True) detections = torch.cat((image_pred[:, :5], class_confs.float(), class_preds.float()), 1) # Perform non-maximum suppression keep_boxes = [] while detections.size(0): large_overlap = bbox_iou(detections[0, :4].unsqueeze(0), detections[:, :4]) > nms_thres label_match = detections[0, -1] == detections[:, -1] # Indices of boxes with lower confidence scores, large IOUs and matching labels invalid = large_overlap & label_match weights = detections[invalid, 4:5] # Merge overlapping bboxes by order of confidence detections[0, :4] = (weights * detections[invalid, :4]).sum(0) / weights.sum() keep_boxes += [detections[0]] detections = detections[~invalid] if keep_boxes: output[image_i] = torch.stack(keep_boxes) return output
def rescale_boxes(boxes, current_dim, original_shape)
-
Rescales bounding boxes to the original shape
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def rescale_boxes(boxes, current_dim, original_shape): """ Rescales bounding boxes to the original shape """ orig_h, orig_w = original_shape # The amount of padding that was added pad_x = max(orig_h - orig_w, 0) * (current_dim / max(original_shape)) pad_y = max(orig_w - orig_h, 0) * (current_dim / max(original_shape)) # Image height and width after padding is removed unpad_h = current_dim - pad_y unpad_w = current_dim - pad_x # Rescale bounding boxes to dimension of original image boxes[:, 0] = ((boxes[:, 0] - pad_x // 2) / unpad_w) * orig_w boxes[:, 1] = ((boxes[:, 1] - pad_y // 2) / unpad_h) * orig_h boxes[:, 2] = ((boxes[:, 2] - pad_x // 2) / unpad_w) * orig_w boxes[:, 3] = ((boxes[:, 3] - pad_y // 2) / unpad_h) * orig_h return boxes
def to_cpu(tensor)
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def to_cpu(tensor): return tensor.detach().cpu()
def weights_init_normal(m)
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def weights_init_normal(m): classname = m.__class__.__name__ if classname.find("Conv") != -1: torch.nn.init.normal_(m.weight.data, 0.0, 0.02) elif classname.find("BatchNorm2d") != -1: torch.nn.init.normal_(m.weight.data, 1.0, 0.02) torch.nn.init.constant_(m.bias.data, 0.0)
def xywh2xyxy(x)
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def xywh2xyxy(x): y = x.new(x.shape) y[..., 0] = x[..., 0] - x[..., 2] / 2 y[..., 1] = x[..., 1] - x[..., 3] / 2 y[..., 2] = x[..., 0] + x[..., 2] / 2 y[..., 3] = x[..., 1] + x[..., 3] / 2 return y