def execute(self, x1, x2):
x1 = nn.relu(self.fc1a(x1))
x1 = self.fc1b(x1)
x2 = nn.relu(self.fc2a(x2))
x2 = self.fc2b(x2)
x = jt.contrib.concat((x1, x2), dim=0)
return nn.log_softmax(x, dim=1)
def execute(self, x):
x = nn.relu(nn.max_pool2d(self.conv1(x), 2))
x = nn.relu(nn.max_pool2d(self.conv2_drop(self.conv2(x)), 2))
x = x.view(((-1), 320))
x = nn.relu(self.fc1(x))
x = self.fc2(x)
return nn.log_softmax(x, dim=1), x
def focal_conf_loss(self, conf_data, conf_t):
"""
Focal loss as described in https://arxiv.org/pdf/1708.02002.pdf
Adapted from https://github.com/clcarwin/focal_loss_pyjt/blob/master/focalloss.py
Note that this uses softmax and not the original sigmoid from the paper.
"""
conf_t = conf_t.view(-1) # [batch_size*num_priors]
conf_data = conf_data.view(-1, conf_data.shape[-1]) # [batch_size*num_priors, num_classes]
# Ignore neutral samples (class < 0)
keep = (conf_t >= 0).float()
conf_t[conf_t < 0] = 0 # so that gather doesn't drum up a fuss
logpt = nn.log_softmax(conf_data, dim=-1)
logpt = logpt.gather(1, conf_t.unsqueeze(-1))
logpt = logpt.view(-1)
pt = logpt.exp()
# I adapted the alpha_t calculation here from
# https://github.com/pyjt/pyjt/blob/master/modules/detectron/softmax_focal_loss_op.cu
# You'd think you want all the alphas to sum to one, but in the original implementation they
# just give background an alpha of 1-alpha and each forground an alpha of alpha.
background = (conf_t == 0).float()
at = (1 - cfg.focal_loss_alpha) * background + cfg.focal_loss_alpha * (1 - background)
loss = -at * (1 - pt) ** cfg.focal_loss_gamma * logpt
# See comment above for keep
return cfg.conf_alpha * (loss * keep).sum()
def execute(self):
x, edge_index, edge_weight = data.x, data.edge_index, data.edge_attr
x = nn.dropout(x, self.dropout)
x = x_0 = nn.relu(self.lins[0](x))
for conv in self.convs:
x = nn.dropout(x, self.dropout)
x = conv(x, x_0, edge_index, edge_weight)
x = nn.relu(x)
x = nn.dropout(x, self.dropout)
x = self.lins[1](x)
return nn.log_softmax(x, dim=-1)
def execute(self):
x, edge_index = data.x, data.edge_index
x = self.conv1(x, edge_index)
return nn.log_softmax(x, dim=1)
def execute(self):
x, edge_index, edge_weight = data.x, data.edge_index, data.edge_attr
x = nn.relu(self.conv1(x, edge_index, edge_weight))
x = nn.dropout(x)
x = self.conv2(x, edge_index, edge_weight)
return nn.log_softmax(x, dim=1)
def execute(self, net, predictions, targets, masks, num_crowds):
"""Multibox Loss
Args:
predictions (tuple): A tuple containing loc preds, conf preds,
mask preds, and prior boxes from SSD net.
loc shape: jt.size(batch_size,num_priors,4)
conf shape: jt.size(batch_size,num_priors,num_classes)
masks shape: jt.size(batch_size,num_priors,mask_dim)
priors shape: jt.size(num_priors,4)
proto* shape: jt.size(batch_size,mask_h,mask_w,mask_dim)
targets (list<tensor>): Ground truth boxes and labels for a batch,
shape: [batch_size][num_objs,5] (last idx is the label).
masks (list<tensor>): Ground truth masks for each object in each image,
shape: [batch_size][num_objs,im_height,im_width]
num_crowds (list<int>): Number of crowd annotations per batch. The crowd
annotations should be the last num_crowds elements of targets and masks.
* Only if mask_type == lincomb
"""
loc_data = predictions['loc']
conf_data = predictions['conf']
mask_data = predictions['mask']
priors = predictions['priors']
if cfg.mask_type == mask_type.lincomb:
proto_data = predictions['proto']
score_data = predictions['score'] if cfg.use_mask_scoring else None
inst_data = predictions['inst'] if cfg.use_instance_coeff else None
labels = [None] * len(targets) # Used in sem segm loss
batch_size = loc_data.shape[0]
num_priors = priors.shape[0]
num_classes = self.num_classes
# Match priors (default boxes) and ground truth boxes
# These tensors will be created with the same device as loc_data
loc_t = jt.empty((batch_size, num_priors, 4),dtype=loc_data.dtype)
gt_box_t = jt.empty((batch_size, num_priors, 4),dtype=loc_data.dtype)
conf_t = jt.empty((batch_size, num_priors)).int32()
idx_t = jt.empty((batch_size, num_priors)).int32()
if cfg.use_class_existence_loss:
class_existence_t = jt.empty((batch_size, num_classes-1),dtype=loc_data.dtype)
# jt.sync(list(predictions.values()))
for idx in range(batch_size):
truths = targets[idx][:, :-1]
labels[idx] = targets[idx][:, -1].int32()
if cfg.use_class_existence_loss:
# Construct a one-hot vector for each object and collapse it into an existence vector with max
# Also it's fine to include the crowd annotations here
class_existence_t[idx,:] = jt.eye(num_classes-1)[labels[idx]].max(dim=0)[0]
# Split the crowd annotations because they come bundled in
cur_crowds = num_crowds[idx]
if cur_crowds > 0:
split = lambda x: (x[-cur_crowds:], x[:-cur_crowds])
crowd_boxes, truths = split(truths)
# We don't use the crowd labels or masks
_, labels[idx] = split(labels[idx])
_, masks[idx] = split(masks[idx])
else:
crowd_boxes = None
match(self.pos_threshold, self.neg_threshold,
truths, priors, labels[idx], crowd_boxes,
loc_t, conf_t, idx_t, idx, loc_data[idx])
gt_box_t[idx,:,:] = truths[idx_t[idx]]
# wrap targets
loc_t.stop_grad()
conf_t.stop_grad()
idx_t.stop_grad()
pos = conf_t > 0
num_pos = pos.sum(dim=1, keepdims=True)
# Shape: [batch,num_priors,4]
pos_idx = pos.unsqueeze(pos.ndim).expand_as(loc_data)
losses = {}
# Localization Loss (Smooth L1)
if cfg.train_boxes:
loc_p = loc_data[pos_idx].view(-1, 4)
loc_t = loc_t[pos_idx].view(-1, 4)
# print(loc_t)
losses['B'] = nn.smooth_l1_loss(loc_p, loc_t, reduction='sum') * cfg.bbox_alpha
if cfg.train_masks:
if cfg.mask_type == mask_type.direct:
if cfg.use_gt_bboxes:
pos_masks = []
for idx in range(batch_size):
pos_masks.append(masks[idx][idx_t[idx, pos[idx]]])
masks_t = jt.contrib.concat(pos_masks, 0)
masks_p = mask_data[pos, :].view(-1, cfg.mask_dim)
losses['M'] = nn.bce_loss(jt.clamp(masks_p, 0, 1), masks_t, size_average=False) * cfg.mask_alpha
else:
losses['M'] = self.direct_mask_loss(pos_idx, idx_t, loc_data, mask_data, priors, masks)
elif cfg.mask_type == mask_type.lincomb:
ret = self.lincomb_mask_loss(pos, idx_t, loc_data, mask_data, priors, proto_data, masks, gt_box_t, score_data, inst_data, labels)
if cfg.use_maskiou:
loss, maskiou_targets = ret
else:
loss = ret
losses.update(loss)
if cfg.mask_proto_loss is not None:
if cfg.mask_proto_loss == 'l1':
losses['P'] = jt.mean(jt.abs(proto_data)) / self.l1_expected_area * self.l1_alpha
elif cfg.mask_proto_loss == 'disj':
losses['P'] = -jt.mean(jt.max(nn.log_softmax(proto_data, dim=-1), dim=-1)[0])
# Confidence loss
if cfg.use_focal_loss:
if cfg.use_sigmoid_focal_loss:
losses['C'] = self.focal_conf_sigmoid_loss(conf_data, conf_t)
elif cfg.use_objectness_score:
losses['C'] = self.focal_conf_objectness_loss(conf_data, conf_t)
else:
losses['C'] = self.focal_conf_loss(conf_data, conf_t)
else:
if cfg.use_objectness_score:
losses['C'] = self.conf_objectness_loss(conf_data, conf_t, batch_size, loc_p, loc_t, priors)
else:
losses['C'] = self.ohem_conf_loss(conf_data, conf_t, pos, batch_size)
# Mask IoU Loss
if cfg.use_maskiou and maskiou_targets is not None:
losses['I'] = self.mask_iou_loss(net, maskiou_targets)
# These losses also don't depend on anchors
if cfg.use_class_existence_loss:
losses['E'] = self.class_existence_loss(predictions['classes'], class_existence_t)
if cfg.use_semantic_segmentation_loss:
losses['S'] = self.semantic_segmentation_loss(predictions['segm'], masks, labels)
# Divide all losses by the number of positives.
# Don't do it for loss[P] because that doesn't depend on the anchors.
total_num_pos = num_pos.sum().float()
for k in losses:
if k not in ('P', 'E', 'S'):
losses[k] /= total_num_pos
else:
losses[k] /= batch_size
# Loss Key:
# - B: Box Localization Loss
# - C: Class Confidence Loss
# - M: Mask Loss
# - P: Prototype Loss
# - D: Coefficient Diversity Loss
# - E: Class Existence Loss
# - S: Semantic Segmentation Loss
return losses
