def pse_decode(preds,
text_repr_type='poly',
min_kernel_confidence=0.5,
min_text_avg_confidence=0.85,
min_kernel_area=0,
min_text_area=16):
"""Decoding predictions of PSENet to instances. This is partially adapted
from https://github.com/whai362/PSENet.
Args:
preds (tensor): The head output tensor of size nxHxW.
text_repr_type (str): The boundary encoding type 'poly' or 'quad'.
min_text_confidence (float): The minimal text confidence.
min_kernel_confidence (float): The minimal kernel confidence.
min_text_avg_confidence (float): The minimal text average confidence.
min_kernel_area (int): The minimal text kernel area.
min_text_area (int): The minimal text instance region area.
Returns:
boundaries: (list[list[float]]): The instance boundary and its
instance confidence list.
"""
preds = torch.sigmoid(preds) # text confidence
score = preds[0, :, :]
masks = preds > min_kernel_confidence
text_mask = masks[0, :, :]
kernel_masks = masks[0:, :, :] * text_mask
score = score.data.cpu().numpy().astype(np.float32) # to numpy
kernel_masks = kernel_masks.data.cpu().numpy().astype(np.uint8) # to numpy
from .pse import pse
region_num, labels = cv2.connectedComponents(kernel_masks[-1],
connectivity=4)
# labels = pse(kernel_masks, min_kernel_area)
labels = pse(kernel_masks, min_kernel_area, labels, region_num)
labels = np.array(labels)
label_num = np.max(labels) + 1
boundaries = []
for i in range(1, label_num):
points = np.array(np.where(labels == i)).transpose((1, 0))[:, ::-1]
area = points.shape[0]
score_instance = np.mean(score[labels == i])
if filter_instance(area, score_instance, min_text_area,
min_text_avg_confidence):
continue
vertices_confidence = points2boundary(points, text_repr_type,
score_instance)
if vertices_confidence is not None:
boundaries.append(vertices_confidence)
return boundaries
def pan_decode(preds,
text_repr_type='poly',
min_text_confidence=0.5,
min_kernel_confidence=0.5,
min_text_avg_confidence=0.85,
min_text_area=16):
"""Convert scores to quadrangles via post processing in PANet. This is
partially adapted from https://github.com/WenmuZhou/PAN.pytorch.
Args:
preds (tensor): The head output tensor of size 6xHxW.
text_repr_type (str): The boundary encoding type 'poly' or 'quad'.
min_text_confidence (float): The minimal text confidence.
min_kernel_confidence (float): The minimal kernel confidence.
min_text_avg_confidence (float): The minimal text average confidence.
min_text_area (int): The minimal text instance region area.
Returns:
boundaries: (list[list[float]]): The instance boundary and its
instance confidence list.
"""
preds[:2, :, :] = torch.sigmoid(preds[:2, :, :])
preds = preds.detach().cpu().numpy()
text_score = preds[0].astype(np.float32)
text = preds[0] > min_text_confidence
kernel = (preds[1] > min_kernel_confidence) * text
embeddings = preds[2:].transpose((1, 2, 0)) # (h, w, 4)
region_num, labels = cv2.connectedComponents(
kernel.astype(np.uint8), connectivity=4)
contours, _ = cv2.findContours((kernel * 255).astype(np.uint8),
cv2.RETR_LIST, cv2.CHAIN_APPROX_NONE)
kernel_contours = np.zeros(text.shape, dtype='uint8')
cv2.drawContours(kernel_contours, contours, -1, 255)
text_points = pixel_group(text_score, text, embeddings, labels,
kernel_contours, region_num,
min_text_avg_confidence)
boundaries = []
for text_inx, text_point in enumerate(text_points):
text_confidence = text_point[0]
text_point = text_point[2:]
text_point = np.array(text_point, dtype=int).reshape(-1, 2)
area = text_point.shape[0]
if filter_instance(area, text_confidence, min_text_area,
min_text_avg_confidence):
continue
vertices_confidence = points2boundary(text_point, text_repr_type,
text_confidence)
if vertices_confidence is not None:
boundaries.append(vertices_confidence)
return boundaries
def db_decode(preds,
text_repr_type='poly',
mask_thr=0.3,
min_text_score=0.3,
min_text_width=5,
unclip_ratio=1.5,
max_candidates=3000):
"""Decoding predictions of DbNet to instances. This is partially adapted
from https://github.com/MhLiao/DB.
Args:
preds (Tensor): The head output tensor of size nxHxW.
text_repr_type (str): The boundary encoding type 'poly' or 'quad'.
mask_thr (float): The mask threshold value for binarization.
min_text_score (float): The threshold value for converting binary map
to shrink text regions.
min_text_width (int): The minimum width of boundary polygon/box
predicted.
unclip_ratio (float): The unclip ratio for text regions dilation.
max_candidates (int): The maximum candidate number.
Returns:
boundaries: (list[list[float]]): The predicted text boundaries.
"""
prob_map = preds[0, :, :]
text_mask = prob_map > mask_thr
score_map = prob_map.data.cpu().numpy().astype(np.float32)
text_mask = text_mask.data.cpu().numpy().astype(np.uint8) # to numpy
contours, _ = cv2.findContours((text_mask * 255).astype(np.uint8),
cv2.RETR_LIST, cv2.CHAIN_APPROX_SIMPLE)
boundaries = []
for i, poly in enumerate(contours):
if i > max_candidates:
break
epsilon = 0.01 * cv2.arcLength(poly, True)
approx = cv2.approxPolyDP(poly, epsilon, True)
points = approx.reshape((-1, 2))
if points.shape[0] < 4:
continue
score = box_score_fast(score_map, points)
if score < min_text_score:
continue
poly = unclip(points, unclip_ratio=unclip_ratio)
if len(poly) == 0 or isinstance(poly[0], list):
continue
poly = poly.reshape(-1, 2)
poly = points2boundary(poly, text_repr_type, score, min_text_width)
if poly is not None:
boundaries.append(poly)
return boundaries
def __call__(self, preds):
"""
Args:
preds (Tensor): Prediction map with shape :math:`(C, H, W)`.
Returns:
list[list[float]]: The predicted text boundaries.
"""
assert preds.dim() == 3
prob_map = preds[0, :, :]
text_mask = prob_map > self.mask_thr
score_map = prob_map.data.cpu().numpy().astype(np.float32)
text_mask = text_mask.data.cpu().numpy().astype(np.uint8) # to numpy
contours, _ = cv2.findContours((text_mask * 255).astype(np.uint8),
cv2.RETR_LIST, cv2.CHAIN_APPROX_SIMPLE)
boundaries = []
for i, poly in enumerate(contours):
if i > self.max_candidates:
break
epsilon = 0.01 * cv2.arcLength(poly, True)
approx = cv2.approxPolyDP(poly, epsilon, True)
points = approx.reshape((-1, 2))
if points.shape[0] < 4:
continue
score = box_score_fast(score_map, points)
if score < self.min_text_score:
continue
poly = unclip(points, unclip_ratio=self.unclip_ratio)
if len(poly) == 0 or isinstance(poly[0], list):
continue
poly = poly.reshape(-1, 2)
if self.text_repr_type == 'quad':
poly = points2boundary(poly, self.text_repr_type, score,
self.min_text_width)
elif self.text_repr_type == 'poly':
poly = poly.flatten().tolist()
if score is not None:
poly = poly + [score]
if len(poly) < 8:
poly = None
if poly is not None:
boundaries.append(poly)
return boundaries
def __call__(self, preds):
"""
Args:
preds (Tensor): Prediction map with shape :math:`(C, H, W)`.
Returns:
list[list[float]]: The instance boundary and its confidence.
"""
assert preds.dim() == 3
preds[:2, :, :] = torch.sigmoid(preds[:2, :, :])
preds = preds.detach().cpu().numpy()
text_score = preds[0].astype(np.float32)
text = preds[0] > self.min_text_confidence
kernel = (preds[1] > self.min_kernel_confidence) * text
embeddings = preds[2:].transpose((1, 2, 0)) # (h, w, 4)
region_num, labels = cv2.connectedComponents(
kernel.astype(np.uint8), connectivity=4)
contours, _ = cv2.findContours((kernel * 255).astype(np.uint8),
cv2.RETR_LIST, cv2.CHAIN_APPROX_NONE)
kernel_contours = np.zeros(text.shape, dtype='uint8')
cv2.drawContours(kernel_contours, contours, -1, 255)
text_points = pixel_group(text_score, text, embeddings, labels,
kernel_contours, region_num,
self.min_text_avg_confidence)
boundaries = []
for text_point in text_points:
text_confidence = text_point[0]
text_point = text_point[2:]
text_point = np.array(text_point, dtype=int).reshape(-1, 2)
area = text_point.shape[0]
if not self.is_valid_instance(area, text_confidence,
self.min_text_area,
self.min_text_avg_confidence):
continue
vertices_confidence = points2boundary(text_point,
self.text_repr_type,
text_confidence)
if vertices_confidence is not None:
boundaries.append(vertices_confidence)
return boundaries
def __call__(self, preds):
"""
Args:
preds (Tensor): Prediction map with shape :math:`(C, H, W)`.
Returns:
list[list[float]]: The instance boundary and its confidence.
"""
assert preds.dim() == 3
preds = torch.sigmoid(preds) # text confidence
score = preds[0, :, :]
masks = preds > self.min_kernel_confidence
text_mask = masks[0, :, :]
kernel_masks = masks[0:, :, :] * text_mask
score = score.data.cpu().numpy().astype(np.float32)
kernel_masks = kernel_masks.data.cpu().numpy().astype(np.uint8)
region_num, labels = cv2.connectedComponents(kernel_masks[-1],
connectivity=4)
labels = contour_expand(kernel_masks, labels, self.min_kernel_area,
region_num)
labels = np.array(labels)
label_num = np.max(labels)
boundaries = []
for i in range(1, label_num + 1):
points = np.array(np.where(labels == i)).transpose((1, 0))[:, ::-1]
area = points.shape[0]
score_instance = np.mean(score[labels == i])
if not self.is_valid_instance(area, score_instance,
self.min_text_area,
self.min_text_avg_confidence):
continue
vertices_confidence = points2boundary(points, self.text_repr_type,
score_instance)
if vertices_confidence is not None:
boundaries.append(vertices_confidence)
return boundaries
def pan_decode(preds,
text_repr_type='poly',
min_text_confidence=0.5,
min_kernel_confidence=0.5,
min_text_avg_confidence=0.85,
min_kernel_area=0,
min_text_area=16):
"""Convert scores to quadrangles via post processing in PANet. This is
partially adapted from https://github.com/WenmuZhou/PAN.pytorch.
Args:
preds (tensor): The head output tensor of size 6xHxW.
text_repr_type (str): The boundary encoding type 'poly' or 'quad'.
min_text_confidence (float): The minimal text confidence.
min_kernel_confidence (float): The minimal kernel confidence.
min_text_avg_confidence (float): The minimal text average confidence.
min_kernel_area (int): The minimal text kernel area.
min_text_area (int): The minimal text instance region area.
Returns:
boundaries: (list[list[float]]): The instance boundary and its
instance confidence list.
"""
from .pan import assign_pixels, estimate_text_confidence, get_pixel_num
preds[:2, :, :] = torch.sigmoid(preds[:2, :, :])
preds = preds.detach().cpu().numpy()
text_score = preds[0].astype(np.float32)
text = preds[0] > min_text_confidence
kernel = (preds[1] > min_kernel_confidence) * text
embeddings = preds[2:].transpose((1, 2, 0)) # (h, w, 4)
region_num, labels = cv2.connectedComponents(kernel.astype(np.uint8),
connectivity=4)
valid_kernel_inx = []
region_pixel_num = get_pixel_num(labels, region_num)
# from inx 1. 0: meaningless.
for region_idx in range(1, region_num):
if region_pixel_num[region_idx] < min_kernel_area:
continue
valid_kernel_inx.append(region_idx)
# assign pixels to valid kernels
assignment = assign_pixels(text.astype(np.uint8), embeddings, labels,
region_num, 0.8)
assignment = assignment.reshape(text.shape)
boundaries = []
# compute text avg confidence
text_points = estimate_text_confidence(assignment, text_score, region_num)
for text_inx, text_point in text_points.items():
if text_inx not in valid_kernel_inx:
continue
text_confidence = text_point[0]
text_point = text_point[2:]
text_point = np.array(text_point, dtype=int).reshape(-1, 2)
area = text_point.shape[0]
if filter_instance(area, text_confidence, min_text_area,
min_text_avg_confidence):
continue
vertices_confidence = points2boundary(text_point, text_repr_type,
text_confidence)
if vertices_confidence is not None:
boundaries.append(vertices_confidence)
return boundaries