class MaskRCNN():
"""Encapsulates the Mask RCNN model functionality.
The actual Keras model is in the keras_model property.
"""
def __init__(self, mode, config, model_dir):
"""
mode: Either "training" or "inference"
config: A Sub-class of the Config class
model_dir: Directory to save training logs and trained weights
"""
assert mode in ['training', 'inference']
self.mode = mode
self.config = config
self.model_dir = model_dir
self.set_log_dir()
self.keras_model = self.build(mode=mode, config=config)
def build(self, mode, config):
"""Build Mask R-CNN architecture.
input_shape: The shape of the input image.
mode: Either "training" or "inference". The inputs and
outputs of the model differ accordingly.
"""
assert mode in ['training', 'inference']
# Image size must be dividable by 2 multiple times
h, w = config.IMAGE_SHAPE[:2]
if h / 2**6 != int(h / 2**6) or w / 2**6 != int(w / 2**6):
raise Exception("Image size must be dividable by 2 at least 6 times "
"to avoid fractions when downscaling and upscaling."
"For example, use 256, 320, 384, 448, 512, ... etc. ")
# Inputs
input_image = KL.Input(
shape=config.IMAGE_SHAPE.tolist(), name="input_image")
input_image_meta = KL.Input(shape=[None], name="input_image_meta")
if mode == "training":
# RPN GT
input_rpn_match = KL.Input(
shape=[None, 1], name="input_rpn_match", dtype=tf.int32)
input_rpn_bbox = KL.Input(
shape=[None, 4], name="input_rpn_bbox", dtype=tf.float32)
# Detection GT (class IDs, bounding boxes, and masks)
# 1. GT Class IDs (zero padded)
input_gt_class_ids = KL.Input(
shape=[None], name="input_gt_class_ids", dtype=tf.int32)
# 2. GT Boxes in pixels (zero padded)
# [batch, MAX_GT_INSTANCES, (y1, x1, y2, x2)] in image coordinates
input_gt_boxes = KL.Input(
shape=[None, 4], name="input_gt_boxes", dtype=tf.float32)
# Normalize coordinates
h, w = K.shape(input_image)[1], K.shape(input_image)[2]
image_scale = K.cast(K.stack([h, w, h, w], axis=0), tf.float32)
gt_boxes = KL.Lambda(lambda x: x / image_scale)(input_gt_boxes)
# 3. GT Masks (zero padded)
# [batch, height, width, MAX_GT_INSTANCES]
if config.USE_MINI_MASK:
input_gt_masks = KL.Input(
shape=[config.MINI_MASK_SHAPE[0],
config.MINI_MASK_SHAPE[1], None],
name="input_gt_masks", dtype=bool)
else:
input_gt_masks = KL.Input(
shape=[config.IMAGE_SHAPE[0], config.IMAGE_SHAPE[1], None],
name="input_gt_masks", dtype=bool)
# Build the shared convolutional layers.
# Bottom-up Layers
# Returns a list of the last layers of each stage, 5 in total.
# Don't create the thead (stage 5), so we pick the 4th item in the list.
_, C2, C3, C4, C5 = resnet_graph(input_image, config.BACKBONE, stage5=True)
# Top-down Layers
# TODO: add assert to varify feature map sizes match what's in config
P5 = KL.Conv2D(256, (1, 1), name='fpn_c5p5')(C5)
P4 = KL.Add(name="fpn_p4add")([
KL.UpSampling2D(size=(2, 2), name="fpn_p5upsampled")(P5),
KL.Conv2D(256, (1, 1), name='fpn_c4p4')(C4)])
P3 = KL.Add(name="fpn_p3add")([
KL.UpSampling2D(size=(2, 2), name="fpn_p4upsampled")(P4),
KL.Conv2D(256, (1, 1), name='fpn_c3p3')(C3)])
P2 = KL.Add(name="fpn_p2add")([
KL.UpSampling2D(size=(2, 2), name="fpn_p3upsampled")(P3),
KL.Conv2D(256, (1, 1), name='fpn_c2p2')(C2)])
# Attach 3x3 conv to all P layers to get the final feature maps.
P2 = KL.Conv2D(256, (3, 3), padding="SAME", name="fpn_p2")(P2)
P3 = KL.Conv2D(256, (3, 3), padding="SAME", name="fpn_p3")(P3)
P4 = KL.Conv2D(256, (3, 3), padding="SAME", name="fpn_p4")(P4)
P5 = KL.Conv2D(256, (3, 3), padding="SAME", name="fpn_p5")(P5)
# P6 is used for the 5th anchor scale in RPN. Generated by
# subsampling from P5 with stride of 2.
P6 = KL.MaxPooling2D(pool_size=(1, 1), strides=2, name="fpn_p6")(P5)
# Note that P6 is used in RPN, but not in the classifier heads.
rpn_feature_maps = [P2, P3, P4, P5, P6]
mrcnn_feature_maps = [P2, P3, P4, P5]
# Generate Anchors
self.anchors = utils.generate_pyramid_anchors(config.RPN_ANCHOR_SCALES,
config.RPN_ANCHOR_RATIOS,
config.BACKBONE_SHAPES,
config.BACKBONE_STRIDES,
config.RPN_ANCHOR_STRIDE)
# RPN Model
rpn = build_rpn_model(config.RPN_ANCHOR_STRIDE,
len(config.RPN_ANCHOR_RATIOS), 256)
# Loop through pyramid layers
layer_outputs = [] # list of lists
for p in rpn_feature_maps:
layer_outputs.append(rpn([p]))
# Concatenate layer outputs
# Convert from list of lists of level outputs to list of lists
# of outputs across levels.
# e.g. [[a1, b1, c1], [a2, b2, c2]] => [[a1, a2], [b1, b2], [c1, c2]]
output_names = ["rpn_class_logits", "rpn_class", "rpn_bbox"]
outputs = list(zip(*layer_outputs))
outputs = [KL.Concatenate(axis=1, name=n)(list(o))
for o, n in zip(outputs, output_names)]
rpn_class_logits, rpn_class, rpn_bbox = outputs
# Generate proposals
# Proposals are [batch, N, (y1, x1, y2, x2)] in normalized coordinates
# and zero padded.
proposal_count = config.POST_NMS_ROIS_TRAINING if mode == "training"\
else config.POST_NMS_ROIS_INFERENCE
rpn_rois = ProposalLayer(proposal_count=proposal_count,
nms_threshold=config.RPN_NMS_THRESHOLD,
name="ROI",
anchors=self.anchors,
config=config)([rpn_class, rpn_bbox])
if mode == "training":
# Class ID mask to mark class IDs supported by the dataset the image
# came from.
_, _, _, active_class_ids = KL.Lambda(lambda x: parse_image_meta_graph(x),
mask=[None, None, None, None])(input_image_meta)
if not config.USE_RPN_ROIS:
# Ignore predicted ROIs and use ROIs provided as an input.
input_rois = KL.Input(shape=[config.POST_NMS_ROIS_TRAINING, 4],
name="input_roi", dtype=np.int32)
# Normalize coordinates to 0-1 range.
target_rois = KL.Lambda(lambda x: K.cast(
x, tf.float32) / image_scale[:4])(input_rois)
else:
target_rois = rpn_rois
# Generate detection targets
# Subsamples proposals and generates target outputs for training
# Note that proposal class IDs, gt_boxes, and gt_masks are zero
# padded. Equally, returned rois and targets are zero padded.
rois, target_class_ids, target_bbox, target_mask =\
DetectionTargetLayer(config, name="proposal_targets")([
target_rois, input_gt_class_ids, gt_boxes, input_gt_masks])
# Network Heads
# TODO: verify that this handles zero padded ROIs
mrcnn_class_logits, mrcnn_class, mrcnn_bbox =\
fpn_classifier_graph(rois, mrcnn_feature_maps, config.IMAGE_SHAPE,
config.POOL_SIZE, config.NUM_CLASSES)
mrcnn_mask = build_fpn_mask_graph(rois, mrcnn_feature_maps,
config.IMAGE_SHAPE,
config.MASK_POOL_SIZE,
config.NUM_CLASSES)
# TODO: clean up (use tf.identify if necessary)
output_rois = KL.Lambda(lambda x: x * 1, name="output_rois")(rois)
# Losses
rpn_class_loss = KL.Lambda(lambda x: rpn_class_loss_graph(*x), name="rpn_class_loss")(
[input_rpn_match, rpn_class_logits])
rpn_bbox_loss = KL.Lambda(lambda x: rpn_bbox_loss_graph(config, *x), name="rpn_bbox_loss")(
[input_rpn_bbox, input_rpn_match, rpn_bbox])
class_loss = KL.Lambda(lambda x: mrcnn_class_loss_graph(*x), name="mrcnn_class_loss")(
[target_class_ids, mrcnn_class_logits, active_class_ids])
bbox_loss = KL.Lambda(lambda x: mrcnn_bbox_loss_graph(*x), name="mrcnn_bbox_loss")(
[target_bbox, target_class_ids, mrcnn_bbox])
mask_loss = KL.Lambda(lambda x: mrcnn_mask_loss_graph(*x), name="mrcnn_mask_loss")(
[target_mask, target_class_ids, mrcnn_mask])
# Model
inputs = [input_image, input_image_meta,
input_rpn_match, input_rpn_bbox, input_gt_class_ids, input_gt_boxes, input_gt_masks]
if not config.USE_RPN_ROIS:
inputs.append(input_rois)
outputs = [rpn_class_logits, rpn_class, rpn_bbox,
mrcnn_class_logits, mrcnn_class, mrcnn_bbox, mrcnn_mask,
rpn_rois, output_rois,
rpn_class_loss, rpn_bbox_loss, class_loss, bbox_loss, mask_loss]
model = KM.Model(inputs, outputs, name='mask_rcnn')
else:
# Network Heads
# Proposal classifier and BBox regressor heads
mrcnn_class_logits, mrcnn_class, mrcnn_bbox =\
fpn_classifier_graph(rpn_rois, mrcnn_feature_maps, config.IMAGE_SHAPE,
config.POOL_SIZE, config.NUM_CLASSES)
# Detections
# output is [batch, num_detections, (y1, x1, y2, x2, class_id, score)] in image coordinates
detections = DetectionLayer(config, name="mrcnn_detection")(
[rpn_rois, mrcnn_class, mrcnn_bbox, input_image_meta])
# Convert boxes to normalized coordinates
# TODO: let DetectionLayer return normalized coordinates to avoid
# unnecessary conversions
h, w = config.IMAGE_SHAPE[:2]
detection_boxes = KL.Lambda(
lambda x: x[..., :4] / np.array([h, w, h, w]))(detections)
# Create masks for detections
mrcnn_mask = build_fpn_mask_graph(detection_boxes, mrcnn_feature_maps,
config.IMAGE_SHAPE,
config.MASK_POOL_SIZE,
config.NUM_CLASSES)
model = KM.Model([input_image, input_image_meta],
[detections, mrcnn_class, mrcnn_bbox,
mrcnn_mask, rpn_rois, rpn_class, rpn_bbox],
name='mask_rcnn')
# Add multi-GPU support.
if config.GPU_COUNT > 1:
from parallel_model import ParallelModel
model = ParallelModel(model, config.GPU_COUNT)
return model
def find_last(self):
"""Finds the last checkpoint file of the last trained model in the
model directory.
Returns:
log_dir: The directory where events and weights are saved
checkpoint_path: the path to the last checkpoint file
"""
# Get directory names. Each directory corresponds to a model
dir_names = next(os.walk(self.model_dir))[1]
key = self.config.NAME.lower()
dir_names = filter(lambda f: f.startswith(key), dir_names)
dir_names = sorted(dir_names)
if not dir_names:
return None, None
# Pick last directory
dir_name = os.path.join(self.model_dir, dir_names[-1])
# Find the last checkpoint
checkpoints = next(os.walk(dir_name))[2]
checkpoints = filter(lambda f: f.startswith("mask_rcnn"), checkpoints)
checkpoints = sorted(checkpoints)
if not checkpoints:
return dir_name, None
checkpoint = os.path.join(dir_name, checkpoints[-1])
return dir_name, checkpoint
def load_weights(self, filepath, by_name=False, exclude=None):
"""Modified version of the correspoding Keras function with
the addition of multi-GPU support and the ability to exclude
some layers from loading.
exlude: list of layer names to excluce
"""
import h5py
from keras.engine import topology
if exclude:
by_name = True
if h5py is None:
raise ImportError('`load_weights` requires h5py.')
f = h5py.File(filepath, mode='r')
if 'layer_names' not in f.attrs and 'model_weights' in f:
f = f['model_weights']
# In multi-GPU training, we wrap the model. Get layers
# of the inner model because they have the weights.
keras_model = self.keras_model
layers = keras_model.inner_model.layers if hasattr(keras_model, "inner_model")\
else keras_model.layers
# Exclude some layers
if exclude:
layers = filter(lambda l: l.name not in exclude, layers)
if by_name:
topology.load_weights_from_hdf5_group_by_name(f, layers)
else:
topology.load_weights_from_hdf5_group(f, layers)
if hasattr(f, 'close'):
f.close()
# Update the log directory
self.set_log_dir(filepath)
def get_imagenet_weights(self):
"""Downloads ImageNet trained weights from Keras.
Returns path to weights file.
"""
from keras.utils.data_utils import get_file
TF_WEIGHTS_PATH_NO_TOP = 'https://github.com/fchollet/deep-learning-models/'\
'releases/download/v0.2/'\
'resnet50_weights_tf_dim_ordering_tf_kernels_notop.h5'
weights_path = get_file('resnet50_weights_tf_dim_ordering_tf_kernels_notop.h5',
TF_WEIGHTS_PATH_NO_TOP,
cache_subdir='models',
md5_hash='a268eb855778b3df3c7506639542a6af')
return weights_path
def compile(self, learning_rate, momentum):
"""Gets the model ready for training. Adds losses, regularization, and
metrics. Then calls the Keras compile() function.
"""
# Optimizer object
optimizer = keras.optimizers.SGD(lr=learning_rate, momentum=momentum,
clipnorm=5.0)
# Add Losses
# First, clear previously set losses to avoid duplication
self.keras_model._losses = []
self.keras_model._per_input_losses = {}
loss_names = ["rpn_class_loss", "rpn_bbox_loss",
"mrcnn_class_loss", "mrcnn_bbox_loss", "mrcnn_mask_loss"]
for name in loss_names:
layer = self.keras_model.get_layer(name)
if layer.output in self.keras_model.losses:
continue
self.keras_model.add_loss(
tf.reduce_mean(layer.output, keep_dims=True))
# Add L2 Regularization
# Skip gamma and beta weights of batch normalization layers.
reg_losses = [keras.regularizers.l2(self.config.WEIGHT_DECAY)(w) / tf.cast(tf.size(w), tf.float32)
for w in self.keras_model.trainable_weights
if 'gamma' not in w.name and 'beta' not in w.name]
self.keras_model.add_loss(tf.add_n(reg_losses))
# Compile
self.keras_model.compile(optimizer=optimizer, loss=[
None] * len(self.keras_model.outputs))
# Add metrics for losses
for name in loss_names:
if name in self.keras_model.metrics_names:
continue
layer = self.keras_model.get_layer(name)
self.keras_model.metrics_names.append(name)
self.keras_model.metrics_tensors.append(tf.reduce_mean(
layer.output, keep_dims=True))
def set_trainable(self, layer_regex, keras_model=None, indent=0, verbose=1):
"""Sets model layers as trainable if their names match
the given regular expression.
"""
# Print message on the first call (but not on recursive calls)
if verbose > 0 and keras_model is None:
log("Selecting layers to train")
keras_model = keras_model or self.keras_model
# In multi-GPU training, we wrap the model. Get layers
# of the inner model because they have the weights.
layers = keras_model.inner_model.layers if hasattr(keras_model, "inner_model")\
else keras_model.layers
for layer in layers:
# Is the layer a model?
if layer.__class__.__name__ == 'Model':
print("In model: ", layer.name)
self.set_trainable(
layer_regex, keras_model=layer, indent=indent + 4)
continue
if not layer.weights:
continue
# Is it trainable?
trainable = bool(re.fullmatch(layer_regex, layer.name))
# Update layer. If layer is a container, update inner layer.
if layer.__class__.__name__ == 'TimeDistributed':
layer.layer.trainable = trainable
else:
layer.trainable = trainable
# Print trainble layer names
if trainable and verbose > 0:
log("{}{:20} ({})".format(" " * indent, layer.name,
layer.__class__.__name__))
def set_log_dir(self, model_path=None):
"""Sets the model log directory and epoch counter.
model_path: If None, or a format different from what this code uses
then set a new log directory and start epochs from 0. Otherwise,
extract the log directory and the epoch counter from the file
name.
"""
# Set date and epoch counter as if starting a new model
self.epoch = 0
now = datetime.datetime.now()
# If we have a model path with date and epochs use them
if model_path:
# Continue from we left of. Get epoch and date from the file name
# A sample model path might look like:
# /path/to/logs/coco20171029T2315/mask_rcnn_coco_0001.h5
regex = r".*/\w+(\d{4})(\d{2})(\d{2})T(\d{2})(\d{2})/mask\_rcnn\_\w+(\d{4})\.h5"
m = re.match(regex, model_path)
if m:
now = datetime.datetime(int(m.group(1)), int(m.group(2)), int(m.group(3)),
int(m.group(4)), int(m.group(5)))
self.epoch = int(m.group(6)) + 1
# Directory for training logs
self.log_dir = os.path.join(self.model_dir, "{}{:%Y%m%dT%H%M}".format(
self.config.NAME.lower(), now))
# Path to save after each epoch. Include placeholders that get filled by Keras.
self.checkpoint_path = os.path.join(self.log_dir, "mask_rcnn_{}_*epoch*.h5".format(
self.config.NAME.lower()))
self.checkpoint_path = self.checkpoint_path.replace(
"*epoch*", "{epoch:04d}")
def train(self, train_dataset, val_dataset, learning_rate, epochs, layers):
"""Train the model.
train_dataset, val_dataset: Training and validation Dataset objects.
learning_rate: The learning rate to train with
epochs: Number of training epochs. Note that previous training epochs
are considered to be done alreay, so this actually determines
the epochs to train in total rather than in this particaular
call.
layers: Allows selecting wich layers to train. It can be:
- A regular expression to match layer names to train
- One of these predefined values:
heaads: The RPN, classifier and mask heads of the network
all: All the layers
3+: Train Resnet stage 3 and up
4+: Train Resnet stage 4 and up
5+: Train Resnet stage 5 and up
"""
assert self.mode == "training", "Create model in training mode."
# Pre-defined layer regular expressions
layer_regex = {
# all layers but the backbone
"heads": r"(mrcnn\_.*)|(rpn\_.*)|(fpn\_.*)",
# From a specific Resnet stage and up
"3+": r"(res3.*)|(bn3.*)|(res4.*)|(bn4.*)|(res5.*)|(bn5.*)|(mrcnn\_.*)|(rpn\_.*)|(fpn\_.*)",
"4+": r"(res4.*)|(bn4.*)|(res5.*)|(bn5.*)|(mrcnn\_.*)|(rpn\_.*)|(fpn\_.*)",
"5+": r"(res5.*)|(bn5.*)|(mrcnn\_.*)|(rpn\_.*)|(fpn\_.*)",
# All layers
"all": ".*",
}
if layers in layer_regex.keys():
layers = layer_regex[layers]
# Data generators
train_generator = data_generator(train_dataset, self.config, shuffle=True,
batch_size=self.config.BATCH_SIZE)
val_generator = data_generator(val_dataset, self.config, shuffle=True,
batch_size=self.config.BATCH_SIZE,
augment=False)
# Callbacks
callbacks = [
keras.callbacks.TensorBoard(log_dir=self.log_dir,
histogram_freq=0, write_graph=True, write_images=False),
keras.callbacks.ModelCheckpoint(self.checkpoint_path,
verbose=0, save_weights_only=True),
]
# Train
log("\nStarting at epoch {}. LR={}\n".format(self.epoch, learning_rate))
log("Checkpoint Path: {}".format(self.checkpoint_path))
self.set_trainable(layers)
self.compile(learning_rate, self.config.LEARNING_MOMENTUM)
# Work-around for Windows: Keras fails on Windows when using
# multiprocessing workers. See discussion here:
# https://github.com/matterport/Mask_RCNN/issues/13#issuecomment-353124009
if os.name is 'nt':
workers = 0
else:
workers = max(self.config.BATCH_SIZE // 2, 2)
self.keras_model.fit_generator(
train_generator,
initial_epoch=self.epoch,
epochs=epochs,
steps_per_epoch=self.config.STEPS_PER_EPOCH,
callbacks=callbacks,
validation_data=next(val_generator),
validation_steps=self.config.VALIDATION_STEPS,
max_queue_size=100,
workers=workers,
use_multiprocessing=True,
)
self.epoch = max(self.epoch, epochs)
def mold_inputs(self, images):
"""Takes a list of images and modifies them to the format expected
as an input to the neural network.
images: List of image matricies [height,width,depth]. Images can have
different sizes.
Returns 3 Numpy matricies:
molded_images: [N, h, w, 3]. Images resized and normalized.
image_metas: [N, length of meta data]. Details about each image.
windows: [N, (y1, x1, y2, x2)]. The portion of the image that has the
original image (padding excluded).
"""
molded_images = []
image_metas = []
windows = []
for image in images:
# Resize image to fit the model expected size
# TODO: move resizing to mold_image()
molded_image, window, scale, padding = utils.resize_image(
image,
min_dim=self.config.IMAGE_MIN_DIM,
max_dim=self.config.IMAGE_MAX_DIM,
padding=self.config.IMAGE_PADDING)
molded_image = mold_image(molded_image, self.config)
# Build image_meta
image_meta = compose_image_meta(
0, image.shape, window,
np.zeros([self.config.NUM_CLASSES], dtype=np.int32))
# Append
molded_images.append(molded_image)
windows.append(window)
image_metas.append(image_meta)
# Pack into arrays
molded_images = np.stack(molded_images)
image_metas = np.stack(image_metas)
windows = np.stack(windows)
return molded_images, image_metas, windows
def unmold_detections(self, detections, mrcnn_mask, image_shape, window):
"""Reformats the detections of one image from the format of the neural
network output to a format suitable for use in the rest of the
application.
detections: [N, (y1, x1, y2, x2, class_id, score)]
mrcnn_mask: [N, height, width, num_classes]
image_shape: [height, width, depth] Original size of the image before resizing
window: [y1, x1, y2, x2] Box in the image where the real image is
excluding the padding.
Returns:
boxes: [N, (y1, x1, y2, x2)] Bounding boxes in pixels
class_ids: [N] Integer class IDs for each bounding box
scores: [N] Float probability scores of the class_id
masks: [height, width, num_instances] Instance masks
"""
# How many detections do we have?
# Detections array is padded with zeros. Find the first class_id == 0.
zero_ix = np.where(detections[:, 4] == 0)[0]
N = zero_ix[0] if zero_ix.shape[0] > 0 else detections.shape[0]
# Extract boxes, class_ids, scores, and class-specific masks
boxes = detections[:N, :4]
class_ids = detections[:N, 4].astype(np.int32)
scores = detections[:N, 5]
masks = mrcnn_mask[np.arange(N), :, :, class_ids]
# Compute scale and shift to translate coordinates to image domain.
h_scale = image_shape[0] / (window[2] - window[0])
w_scale = image_shape[1] / (window[3] - window[1])
scale = min(h_scale, w_scale)
shift = window[:2] # y, x
scales = np.array([scale, scale, scale, scale])
shifts = np.array([shift[0], shift[1], shift[0], shift[1]])
# Translate bounding boxes to image domain
boxes = np.multiply(boxes - shifts, scales).astype(np.int32)
# Filter out detections with zero area. Often only happens in early
# stages of training when the network weights are still a bit random.
exclude_ix = np.where(
(boxes[:, 2] - boxes[:, 0]) * (boxes[:, 3] - boxes[:, 1]) <= 0)[0]
if exclude_ix.shape[0] > 0:
boxes = np.delete(boxes, exclude_ix, axis=0)
class_ids = np.delete(class_ids, exclude_ix, axis=0)
scores = np.delete(scores, exclude_ix, axis=0)
masks = np.delete(masks, exclude_ix, axis=0)
N = class_ids.shape[0]
# Resize masks to original image size and set boundary threshold.
full_masks = []
for i in range(N):
# Convert neural network mask to full size mask
full_mask = utils.unmold_mask(masks[i], boxes[i], image_shape)
full_masks.append(full_mask)
full_masks = np.stack(full_masks, axis=-1)\
if full_masks else np.empty((0,) + masks.shape[1:3])
return boxes, class_ids, scores, full_masks
def detect(self, images, verbose=0):
"""Runs the detection pipeline.
images: List of images, potentially of different sizes.
Returns a list of dicts, one dict per image. The dict contains:
rois: [N, (y1, x1, y2, x2)] detection bounding boxes
class_ids: [N] int class IDs
scores: [N] float probability scores for the class IDs
masks: [H, W, N] instance binary masks
"""
assert self.mode == "inference", "Create model in inference mode."
assert len(
images) == self.config.BATCH_SIZE, "len(images) must be equal to BATCH_SIZE"
if verbose:
log("Processing {} images".format(len(images)))
for image in images:
log("image", image)
# Mold inputs to format expected by the neural network
molded_images, image_metas, windows = self.mold_inputs(images)
if verbose:
log("molded_images", molded_images)
log("image_metas", image_metas)
# Run object detection
detections, mrcnn_class, mrcnn_bbox, mrcnn_mask, \
rois, rpn_class, rpn_bbox =\
self.keras_model.predict([molded_images, image_metas], verbose=0)
# Process detections
results = []
for i, image in enumerate(images):
final_rois, final_class_ids, final_scores, final_masks =\
self.unmold_detections(detections[i], mrcnn_mask[i],
image.shape, windows[i])
results.append({
"rois": final_rois,
"class_ids": final_class_ids,
"scores": final_scores,
"masks": final_masks,
})
return results
def ancestor(self, tensor, name, checked=None):
"""Finds the ancestor of a TF tensor in the computation graph.
tensor: TensorFlow symbolic tensor.
name: Name of ancestor tensor to find
checked: For internal use. A list of tensors that were already
searched to avoid loops in traversing the graph.
"""
checked = checked if checked is not None else []
# Put a limit on how deep we go to avoid very long loops
if len(checked) > 500:
return None
# Convert name to a regex and allow matching a number prefix
# because Keras adds them automatically
if isinstance(name, str):
name = re.compile(name.replace("/", r"(\_\d+)*/"))
parents = tensor.op.inputs
for p in parents:
if p in checked:
continue
if bool(re.fullmatch(name, p.name)):
return p
checked.append(p)
a = self.ancestor(p, name, checked)
if a is not None:
return a
return None
def find_trainable_layer(self, layer):
"""If a layer is encapsulated by another layer, this function
digs through the encapsulation and returns the layer that holds
the weights.
"""
if layer.__class__.__name__ == 'TimeDistributed':
return self.find_trainable_layer(layer.layer)
return layer
def get_trainable_layers(self):
"""Returns a list of layers that have weights."""
layers = []
# Loop through all layers
for l in self.keras_model.layers:
# If layer is a wrapper, find inner trainable layer
l = self.find_trainable_layer(l)
# Include layer if it has weights
if l.get_weights():
layers.append(l)
return layers
def run_graph(self, images, outputs):
"""Runs a sub-set of the computation graph that computes the given
outputs.
outputs: List of tuples (name, tensor) to compute. The tensors are
symbolic TensorFlow tensors and the names are for easy tracking.
Returns an ordered dict of results. Keys are the names received in the
input and values are Numpy arrays.
"""
model = self.keras_model
# Organize desired outputs into an ordered dict
outputs = OrderedDict(outputs)
for o in outputs.values():
assert o is not None
# Build a Keras function to run parts of the computation graph
inputs = model.inputs
if model.uses_learning_phase and not isinstance(K.learning_phase(), int):
inputs += [K.learning_phase()]
kf = K.function(model.inputs, list(outputs.values()))
# Run inference
molded_images, image_metas, windows = self.mold_inputs(images)
# TODO: support training mode?
# if TEST_MODE == "training":
# model_in = [molded_images, image_metas,
# target_rpn_match, target_rpn_bbox,
# gt_boxes, gt_masks]
# if not config.USE_RPN_ROIS:
# model_in.append(target_rois)
# if model.uses_learning_phase and not isinstance(K.learning_phase(), int):
# model_in.append(1.)
# outputs_np = kf(model_in)
# else:
model_in = [molded_images, image_metas]
if model.uses_learning_phase and not isinstance(K.learning_phase(), int):
model_in.append(0.)
outputs_np = kf(model_in)
# Pack the generated Numpy arrays into a a dict and log the results.
outputs_np = OrderedDict([(k, v)
for k, v in zip(outputs.keys(), outputs_np)])
for k, v in outputs_np.items():
log(k, v)
return outputs_np
# Get all combinations of scales and ratios
scales, ratios = np.meshgrid(np.array(scales), np.array(ratios))
scales = scales.flatten()
ratios = ratios.flatten()
# Reshape to get a list of (y, x) and a list of (h, w)
box_centers = np.stack(
[box_centers_y, box_centers_x], axis=2).reshape([-1, 2])
box_sizes = np.stack([box_heights, box_widths], axis=2).reshape([-1, 2])
可能用到的事务代码：/IWFND/IWF_ACTIVATE – Activate / Deactivate SAP GatewaySEGW – SAP Gateway Service Builder/IWFND/MAINT_SERVICE – Activate and Maintain Services/IWFND/EXPLORER – Service Explorer/IWFND/GW_CLIENT – SAP Gateway Client/IWFND/S…
变成
，这叫做一个”阶段“，因此通过每一个阶段特征图融合在一起相当于既有高层的描述了整个原始图片的语义特征的信息既有低层的描述的单一的轮廓信息）。因此不是简单的做一个图像金字塔，而是对图像进行卷积特征提取后把不同阶段特征拿过来用。
，C2的特征图大小
.....，我们利用
的卷积核可以改变特征层的个数。这里比如C5是
的，我们通过
的卷积核对其进行卷积，得到的P5是
的。同理，P4是
的尺寸，他俩的大小规格不匹配怎么办呢？
和P4进行加法操作进行融合.....。最终得到FPN的五个特征层Predict1、Predict2、Predict3、Predict4、Predict5。
的）。
是
的。（没有使用C1，由于C1尺寸过大会消耗太多的显存资源）
是
的，
是
的，
是
的，
是
的。
的，卷积层数为256层。
的情况：大小由
。
，操作如下：
，同时
的....）
的，256和1024之间差了4倍，我们生成的坐标最终不是生成在特征层上的而是原始图像上的！！！因此我们通过这步将生成的anchors还原到原图像上。
：
