DMPR-PS/train.py

156 lines
6.7 KiB
Python

"""Train directional marking point detector."""
import math
import random
import numpy as np
import torch
import yaml
from torch import nn
from torch.utils.data import DataLoader
import config
import data
import util
from model import DirectionalPointDetector
from models.yolo import Model
# import os
# os.environ['CUDA_VISIBLE_DEVICES'] = '1'
def plot_prediction(logger, image, marking_points, prediction):
"""Plot the ground truth and prediction of a random sample in a batch."""
rand_sample = random.randint(0, image.size(0)-1)
sampled_image = util.tensor2im(image[rand_sample])
logger.plot_marking_points(sampled_image, marking_points[rand_sample],
win_name='gt_marking_points')
sampled_image = util.tensor2im(image[rand_sample])
pred_points = data.get_predicted_points(prediction[rand_sample], 0.01)
if pred_points:
logger.plot_marking_points(sampled_image,
list(list(zip(*pred_points))[1]),
win_name='pred_marking_points')
def generate_objective(marking_points_batch, device):
"""Get regression objective and gradient for directional point detector."""
batch_size = len(marking_points_batch)
objective = torch.zeros(batch_size, config.NUM_FEATURE_MAP_CHANNEL,
config.FEATURE_MAP_SIZE, config.FEATURE_MAP_SIZE,
device=device)
gradient = torch.zeros_like(objective)
gradient[:, 0].fill_(1.)
for batch_idx, marking_points in enumerate(marking_points_batch):
for marking_point in marking_points:
col = math.floor(marking_point.x * config.FEATURE_MAP_SIZE)
row = math.floor(marking_point.y * config.FEATURE_MAP_SIZE)
# Confidence Regression
objective[batch_idx, 0, row, col] = 1.
# Makring Point Shape Regression
objective[batch_idx, 1, row, col] = marking_point.shape
# Offset Regression
objective[batch_idx, 2, row, col] = marking_point.x*config.FEATURE_MAP_SIZE - col
objective[batch_idx, 3, row, col] = marking_point.y*config.FEATURE_MAP_SIZE - row
# Direction Regression
direction = marking_point.direction
objective[batch_idx, 4, row, col] = math.cos(direction)
objective[batch_idx, 5, row, col] = math.sin(direction)
# Assign Gradient
gradient[batch_idx, 1:6, row, col].fill_(1.)
return objective, gradient
# class FocalLoss(nn.Module):
# # Wraps focal loss around existing loss_fcn(), i.e. criteria = FocalLoss(nn.BCEWithLogitsLoss(), gamma=1.5)
# def __init__(self, loss_fcn, gamma=1.5, alpha=0.25):
# super(FocalLoss, self).__init__()
# self.loss_fcn = loss_fcn # must be nn.BCEWithLogitsLoss()
# self.gamma = gamma
# self.alpha = alpha
# self.reduction = loss_fcn.reduction
# self.loss_fcn.reduction = 'none' # required to apply FL to each element
#
# def forward(self, pred, true):
# loss = self.loss_fcn(pred, true)
# # p_t = torch.exp(-loss)
# # loss *= self.alpha * (1.000001 - p_t) ** self.gamma # non-zero power for gradient stability
#
# # TF implementation https://github.com/tensorflow/addons/blob/v0.7.1/tensorflow_addons/losses/focal_loss.py
# pred_prob = torch.sigmoid(pred) # prob from logits
# p_t = true * pred_prob + (1 - true) * (1 - pred_prob)
# alpha_factor = true * self.alpha + (1 - true) * (1 - self.alpha)
# modulating_factor = (1.0 - p_t) ** self.gamma
# loss *= alpha_factor * modulating_factor
#
# if self.reduction == 'mean':
# return loss.mean()
# elif self.reduction == 'sum':
# return loss.sum()
# else: # 'none'
# return loss
def train_detector(args):
"""Train directional point detector."""
args.cuda = not args.disable_cuda and torch.cuda.is_available()
device = torch.device('cuda:' + str(args.gpu_id) if args.cuda else 'cpu')
torch.set_grad_enabled(True)
# dp_detector = DirectionalPointDetector(
# 3, args.depth_factor, config.NUM_FEATURE_MAP_CHANNEL).to(device)
# if args.detector_weights:
# print("Loading weights: %s" % args.detector_weights)
# dp_detector.load_state_dict(torch.load(args.detector_weights))
# dp_detector.train()
with open(args.hyp) as f:
hyp = yaml.load(f, Loader=yaml.SafeLoader)
dp_detector = Model(args.cfg, ch=3, anchors=hyp.get('anchors')).to(device)
if args.detector_weights:
print("Loading weights: %s" % args.detector_weights)
dp_detector.load_state_dict(torch.load(args.detector_weights))
dp_detector.train()
optimizer = torch.optim.Adam(dp_detector.parameters(), lr=args.lr)
if args.optimizer_weights:
print("Loading weights: %s" % args.optimizer_weights)
optimizer.load_state_dict(torch.load(args.optimizer_weights))
logger = util.Logger(args.enable_visdom, ['train_loss'])
data_loader = DataLoader(data.ParkingSlotDataset(args.dataset_directory),
batch_size=args.batch_size, shuffle=True,
num_workers=args.data_loading_workers,
pin_memory=True,
collate_fn=lambda x: list(zip(*x)))
# BCEobj = nn.BCEWithLogitsLoss(reduction='none', pos_weight=torch.tensor([hyp['obj_pw']], device=device))
# # Focal loss
# g = hyp['fl_gamma'] # focal loss gamma
# if g > 0:
# BCEobj = FocalLoss(BCEobj, g)
for epoch_idx in range(args.num_epochs):
for iter_idx, (images, marking_points) in enumerate(data_loader):
images = torch.stack(images).to(device)
# images = torch.from_numpy(np.stack(images, axis=0)).to(device).permute(0, 3, 1, 2)
optimizer.zero_grad()
prediction = dp_detector(images)
objective, gradient = generate_objective(marking_points, device)
# lobj = BCEobj(prediction[:, 0, ...], objective[:, 0, ...])
loss = (prediction - objective) ** 2
# lobj = torch.unsqueeze(lobj, 1)
# loss = torch.cat((lobj, l_sxycs), 1)
loss.backward(gradient)
optimizer.step()
train_loss = torch.sum(loss*gradient).item() / loss.size(0)
logger.log(epoch=epoch_idx, iter=iter_idx, train_loss=train_loss)
if args.enable_visdom:
plot_prediction(logger, images, marking_points, prediction)
torch.save(dp_detector.state_dict(),
'weights/dp_detector_%d.pth' % epoch_idx)
torch.save(optimizer.state_dict(), 'weights/optimizer.pth')
if __name__ == '__main__':
train_detector(config.get_parser_for_training().parse_args())