detectron2.utils.visualizer — detectron2 0.6 documentation (original) (raw)
Copyright (c) Facebook, Inc. and its affiliates.
import colorsys import logging import math import numpy as np from enum import Enum, unique import cv2 import matplotlib as mpl import matplotlib.colors as mplc import matplotlib.figure as mplfigure import pycocotools.mask as mask_util import torch from matplotlib.backends.backend_agg import FigureCanvasAgg from PIL import Image
from detectron2.data import MetadataCatalog from detectron2.structures import BitMasks, Boxes, BoxMode, Keypoints, PolygonMasks, RotatedBoxes from detectron2.utils.file_io import PathManager
from .colormap import random_color
logger = logging.getLogger(name)
all = ["ColorMode", "VisImage", "Visualizer"]
_SMALL_OBJECT_AREA_THRESH = 1000 _LARGE_MASK_AREA_THRESH = 120000 _OFF_WHITE = (1.0, 1.0, 240.0 / 255) _BLACK = (0, 0, 0) _RED = (1.0, 0, 0)
_KEYPOINT_THRESHOLD = 0.05
[docs]@unique class ColorMode(Enum): """ Enum of different color modes to use for instance visualizations. """
IMAGE = 0
"""
Picks a random color for every instance and overlay segmentations with low opacity.
"""
SEGMENTATION = 1
"""
Let instances of the same category have similar colors
(from metadata.thing_colors), and overlay them with
high opacity. This provides more attention on the quality of segmentation.
"""
IMAGE_BW = 2
"""
Same as IMAGE, but convert all areas without masks to gray-scale.
Only available for drawing per-instance mask predictions.
"""class GenericMask: """ Attribute: polygons (list[ndarray]): list[ndarray]: polygons for this mask. Each ndarray has format [x, y, x, y, ...] mask (ndarray): a binary mask """
def __init__(self, mask_or_polygons, height, width):
self._mask = self._polygons = self._has_holes = None
self.height = height
self.width = width
m = mask_or_polygons
if isinstance(m, dict):
# RLEs
assert "counts" in m and "size" in m
if isinstance(m["counts"], list): # uncompressed RLEs
h, w = m["size"]
assert h == height and w == width
m = mask_util.frPyObjects(m, h, w)
self._mask = mask_util.decode(m)[:, :]
return
if isinstance(m, list): # list[ndarray]
self._polygons = [np.asarray(x).reshape(-1) for x in m]
return
if isinstance(m, np.ndarray): # assumed to be a binary mask
assert m.shape[1] != 2, m.shape
assert m.shape == (
height,
width,
), f"mask shape: {m.shape}, target dims: {height}, {width}"
self._mask = m.astype("uint8")
return
raise ValueError("GenericMask cannot handle object {} of type '{}'".format(m, type(m)))
@property
def mask(self):
if self._mask is None:
self._mask = self.polygons_to_mask(self._polygons)
return self._mask
@property
def polygons(self):
if self._polygons is None:
self._polygons, self._has_holes = self.mask_to_polygons(self._mask)
return self._polygons
@property
def has_holes(self):
if self._has_holes is None:
if self._mask is not None:
self._polygons, self._has_holes = self.mask_to_polygons(self._mask)
else:
self._has_holes = False # if original format is polygon, does not have holes
return self._has_holes
def mask_to_polygons(self, mask):
# cv2.RETR_CCOMP flag retrieves all the contours and arranges them to a 2-level
# hierarchy. External contours (boundary) of the object are placed in hierarchy-1.
# Internal contours (holes) are placed in hierarchy-2.
# cv2.CHAIN_APPROX_NONE flag gets vertices of polygons from contours.
mask = np.ascontiguousarray(mask) # some versions of cv2 does not support incontiguous arr
res = cv2.findContours(mask.astype("uint8"), cv2.RETR_CCOMP, cv2.CHAIN_APPROX_NONE)
hierarchy = res[-1]
if hierarchy is None: # empty mask
return [], False
has_holes = (hierarchy.reshape(-1, 4)[:, 3] >= 0).sum() > 0
res = res[-2]
res = [x.flatten() for x in res]
# These coordinates from OpenCV are integers in range [0, W-1 or H-1].
# We add 0.5 to turn them into real-value coordinate space. A better solution
# would be to first +0.5 and then dilate the returned polygon by 0.5.
res = [x + 0.5 for x in res if len(x) >= 6]
return res, has_holes
def polygons_to_mask(self, polygons):
rle = mask_util.frPyObjects(polygons, self.height, self.width)
rle = mask_util.merge(rle)
return mask_util.decode(rle)[:, :]
def area(self):
return self.mask.sum()
def bbox(self):
p = mask_util.frPyObjects(self.polygons, self.height, self.width)
p = mask_util.merge(p)
bbox = mask_util.toBbox(p)
bbox[2] += bbox[0]
bbox[3] += bbox[1]
return bboxclass _PanopticPrediction: """ Unify different panoptic annotation/prediction formats """
def __init__(self, panoptic_seg, segments_info, metadata=None):
if segments_info is None:
assert metadata is not None
# If "segments_info" is None, we assume "panoptic_img" is a
# H*W int32 image storing the panoptic_id in the format of
# category_id * label_divisor + instance_id. We reserve -1 for
# VOID label.
label_divisor = metadata.label_divisor
segments_info = []
for panoptic_label in np.unique(panoptic_seg.numpy()):
if panoptic_label == -1:
# VOID region.
continue
pred_class = panoptic_label // label_divisor
isthing = pred_class in metadata.thing_dataset_id_to_contiguous_id.values()
segments_info.append(
{
"id": int(panoptic_label),
"category_id": int(pred_class),
"isthing": bool(isthing),
}
)
del metadata
self._seg = panoptic_seg
self._sinfo = {s["id"]: s for s in segments_info} # seg id -> seg info
segment_ids, areas = torch.unique(panoptic_seg, sorted=True, return_counts=True)
areas = areas.numpy()
sorted_idxs = np.argsort(-areas)
self._seg_ids, self._seg_areas = segment_ids[sorted_idxs], areas[sorted_idxs]
self._seg_ids = self._seg_ids.tolist()
for sid, area in zip(self._seg_ids, self._seg_areas):
if sid in self._sinfo:
self._sinfo[sid]["area"] = float(area)
def non_empty_mask(self):
"""
Returns:
(H, W) array, a mask for all pixels that have a prediction
"""
empty_ids = []
for id in self._seg_ids:
if id not in self._sinfo:
empty_ids.append(id)
if len(empty_ids) == 0:
return np.zeros(self._seg.shape, dtype=np.uint8)
assert (
len(empty_ids) == 1
), ">1 ids corresponds to no labels. This is currently not supported"
return (self._seg != empty_ids[0]).numpy().astype(bool)
def semantic_masks(self):
for sid in self._seg_ids:
sinfo = self._sinfo.get(sid)
if sinfo is None or sinfo["isthing"]:
# Some pixels (e.g. id 0 in PanopticFPN) have no instance or semantic predictions.
continue
yield (self._seg == sid).numpy().astype(bool), sinfo
def instance_masks(self):
for sid in self._seg_ids:
sinfo = self._sinfo.get(sid)
if sinfo is None or not sinfo["isthing"]:
continue
mask = (self._seg == sid).numpy().astype(bool)
if mask.sum() > 0:
yield mask, sinfodef _create_text_labels(classes, scores, class_names, is_crowd=None): """ Args: classes (list[int] or None): scores (list[float] or None): class_names (list[str] or None): is_crowd (list[bool] or None):
Returns:
list[str] or None
"""
labels = None
if classes is not None:
if class_names is not None and len(class_names) > 0:
labels = [class_names[i] for i in classes]
else:
labels = [str(i) for i in classes]
if scores is not None:
if labels is None:
labels = ["{:.0f}%".format(s * 100) for s in scores]
else:
labels = ["{} {:.0f}%".format(l, s * 100) for l, s in zip(labels, scores)]
if labels is not None and is_crowd is not None:
labels = [l + ("|crowd" if crowd else "") for l, crowd in zip(labels, is_crowd)]
return labels[docs]class VisImage:
[docs] def init(self, img, scale=1.0): """ Args: img (ndarray): an RGB image of shape (H, W, 3) in range [0, 255]. scale (float): scale the input image """ self.img = img self.scale = scale self.width, self.height = img.shape[1], img.shape[0] self._setup_figure(img)
def _setup_figure(self, img):
"""
Args:
Same as in :meth:`__init__()`.
Returns:
fig (matplotlib.pyplot.figure): top level container for all the image plot elements.
ax (matplotlib.pyplot.Axes): contains figure elements and sets the coordinate system.
"""
fig = mplfigure.Figure(frameon=False)
self.dpi = fig.get_dpi()
# add a small 1e-2 to avoid precision lost due to matplotlib's truncation
# (https://github.com/matplotlib/matplotlib/issues/15363)
fig.set_size_inches(
(self.width * self.scale + 1e-2) / self.dpi,
(self.height * self.scale + 1e-2) / self.dpi,
)
self.canvas = FigureCanvasAgg(fig)
# self.canvas = mpl.backends.backend_cairo.FigureCanvasCairo(fig)
ax = fig.add_axes([0.0, 0.0, 1.0, 1.0])
ax.axis("off")
self.fig = fig
self.ax = ax
self.reset_image(img)[docs] def reset_image(self, img): """ Args: img: same as in init """ img = img.astype("uint8") self.ax.imshow(img, extent=(0, self.width, self.height, 0), interpolation="nearest")
[docs] def save(self, filepath): """ Args: filepath (str): a string that contains the absolute path, including the file name, where the visualized image will be saved. """ self.fig.savefig(filepath)
[docs] def get_image(self):
"""
Returns:
ndarray:
the visualized image of shape (H, W, 3) (RGB) in uint8 type.
The shape is scaled w.r.t the input image using the given scale argument.
"""
canvas = self.canvas
s, (width, height) = canvas.print_to_buffer()
# buf = io.BytesIO() # works for cairo backend
# canvas.print_rgba(buf)
# width, height = self.width, self.height
# s = buf.getvalue()
buffer = np.frombuffer(s, dtype="uint8")
img_rgba = buffer.reshape(height, width, 4)
rgb, alpha = np.split(img_rgba, [3], axis=2)
return rgb.astype("uint8")[docs]class Visualizer: """ Visualizer that draws data about detection/segmentation on images.
It contains methods like `draw_{text,box,circle,line,binary_mask,polygon}`
that draw primitive objects to images, as well as high-level wrappers like
`draw_{instance_predictions,sem_seg,panoptic_seg_predictions,dataset_dict}`
that draw composite data in some pre-defined style.
Note that the exact visualization style for the high-level wrappers are subject to change.
Style such as color, opacity, label contents, visibility of labels, or even the visibility
of objects themselves (e.g. when the object is too small) may change according
to different heuristics, as long as the results still look visually reasonable.
To obtain a consistent style, you can implement custom drawing functions with the
abovementioned primitive methods instead. If you need more customized visualization
styles, you can process the data yourself following their format documented in
tutorials (:doc:`/tutorials/models`, :doc:`/tutorials/datasets`). This class does not
intend to satisfy everyone's preference on drawing styles.
This visualizer focuses on high rendering quality rather than performance. It is not
designed to be used for real-time applications.
"""
# TODO implement a fast, rasterized version using OpenCV[docs] def init(self, img_rgb, metadata=None, scale=1.0, instance_mode=ColorMode.IMAGE): """ Args: img_rgb: a numpy array of shape (H, W, C), where H and W correspond to the height and width of the image respectively. C is the number of color channels. The image is required to be in RGB format since that is a requirement of the Matplotlib library. The image is also expected to be in the range [0, 255]. metadata (Metadata): dataset metadata (e.g. class names and colors) instance_mode (ColorMode): defines one of the pre-defined style for drawing instances on an image. """ self.img = np.asarray(img_rgb).clip(0, 255).astype(np.uint8) if metadata is None: metadata = MetadataCatalog.get("nonexist") self.metadata = metadata self.output = VisImage(self.img, scale=scale) self.cpu_device = torch.device("cpu")
# too small texts are useless, therefore clamp to 9
self._default_font_size = max(
np.sqrt(self.output.height * self.output.width) // 90, 10 // scale
)
self._instance_mode = instance_mode
self.keypoint_threshold = _KEYPOINT_THRESHOLD[docs] def draw_instance_predictions(self, predictions): """ Draw instance-level prediction results on an image.
Args:
predictions (Instances): the output of an instance detection/segmentation
model. Following fields will be used to draw:
"pred_boxes", "pred_classes", "scores", "pred_masks" (or "pred_masks_rle").
Returns:
output (VisImage): image object with visualizations.
"""
boxes = predictions.pred_boxes if predictions.has("pred_boxes") else None
scores = predictions.scores if predictions.has("scores") else None
classes = predictions.pred_classes.tolist() if predictions.has("pred_classes") else None
labels = _create_text_labels(classes, scores, self.metadata.get("thing_classes", None))
keypoints = predictions.pred_keypoints if predictions.has("pred_keypoints") else None
if predictions.has("pred_masks"):
masks = np.asarray(predictions.pred_masks)
masks = [GenericMask(x, self.output.height, self.output.width) for x in masks]
else:
masks = None
if self._instance_mode == ColorMode.SEGMENTATION and self.metadata.get("thing_colors"):
colors = [
self._jitter([x / 255 for x in self.metadata.thing_colors[c]]) for c in classes
]
alpha = 0.8
else:
colors = None
alpha = 0.5
if self._instance_mode == ColorMode.IMAGE_BW:
self.output.reset_image(
self._create_grayscale_image(
(predictions.pred_masks.any(dim=0) > 0).numpy()
if predictions.has("pred_masks")
else None
)
)
alpha = 0.3
self.overlay_instances(
masks=masks,
boxes=boxes,
labels=labels,
keypoints=keypoints,
assigned_colors=colors,
alpha=alpha,
)
return self.output[docs] def draw_sem_seg(self, sem_seg, area_threshold=None, alpha=0.8): """ Draw semantic segmentation predictions/labels.
Args:
sem_seg (Tensor or ndarray): the segmentation of shape (H, W).
Each value is the integer label of the pixel.
area_threshold (int): segments with less than `area_threshold` are not drawn.
alpha (float): the larger it is, the more opaque the segmentations are.
Returns:
output (VisImage): image object with visualizations.
"""
if isinstance(sem_seg, torch.Tensor):
sem_seg = sem_seg.numpy()
labels, areas = np.unique(sem_seg, return_counts=True)
sorted_idxs = np.argsort(-areas).tolist()
labels = labels[sorted_idxs]
for label in filter(lambda l: l < len(self.metadata.stuff_classes), labels):
try:
mask_color = [x / 255 for x in self.metadata.stuff_colors[label]]
except (AttributeError, IndexError):
mask_color = None
binary_mask = (sem_seg == label).astype(np.uint8)
text = self.metadata.stuff_classes[label]
self.draw_binary_mask(
binary_mask,
color=mask_color,
edge_color=_OFF_WHITE,
text=text,
alpha=alpha,
area_threshold=area_threshold,
)
return self.output[docs] def draw_panoptic_seg(self, panoptic_seg, segments_info, area_threshold=None, alpha=0.7): """ Draw panoptic prediction annotations or results.
Args:
panoptic_seg (Tensor): of shape (height, width) where the values are ids for each
segment.
segments_info (list[dict] or None): Describe each segment in `panoptic_seg`.
If it is a ``list[dict]``, each dict contains keys "id", "category_id".
If None, category id of each pixel is computed by
``pixel // metadata.label_divisor``.
area_threshold (int): stuff segments with less than `area_threshold` are not drawn.
Returns:
output (VisImage): image object with visualizations.
"""
pred = _PanopticPrediction(panoptic_seg, segments_info, self.metadata)
if self._instance_mode == ColorMode.IMAGE_BW:
self.output.reset_image(self._create_grayscale_image(pred.non_empty_mask()))
# draw mask for all semantic segments first i.e. "stuff"
for mask, sinfo in pred.semantic_masks():
category_idx = sinfo["category_id"]
try:
mask_color = [x / 255 for x in self.metadata.stuff_colors[category_idx]]
except AttributeError:
mask_color = None
text = self.metadata.stuff_classes[category_idx]
self.draw_binary_mask(
mask,
color=mask_color,
edge_color=_OFF_WHITE,
text=text,
alpha=alpha,
area_threshold=area_threshold,
)
# draw mask for all instances second
all_instances = list(pred.instance_masks())
if len(all_instances) == 0:
return self.output
masks, sinfo = list(zip(*all_instances))
category_ids = [x["category_id"] for x in sinfo]
try:
scores = [x["score"] for x in sinfo]
except KeyError:
scores = None
labels = _create_text_labels(
category_ids, scores, self.metadata.thing_classes, [x.get("iscrowd", 0) for x in sinfo]
)
try:
colors = [
self._jitter([x / 255 for x in self.metadata.thing_colors[c]]) for c in category_ids
]
except AttributeError:
colors = None
self.overlay_instances(masks=masks, labels=labels, assigned_colors=colors, alpha=alpha)
return self.output
draw_panoptic_seg_predictions = draw_panoptic_seg # backward compatibility[docs] def draw_dataset_dict(self, dic): """ Draw annotations/segmentations in Detectron2 Dataset format.
Args:
dic (dict): annotation/segmentation data of one image, in Detectron2 Dataset format.
Returns:
output (VisImage): image object with visualizations.
"""
annos = dic.get("annotations", None)
if annos:
if "segmentation" in annos[0]:
masks = [x["segmentation"] for x in annos]
else:
masks = None
if "keypoints" in annos[0]:
keypts = [x["keypoints"] for x in annos]
keypts = np.array(keypts).reshape(len(annos), -1, 3)
else:
keypts = None
boxes = [
BoxMode.convert(x["bbox"], x["bbox_mode"], BoxMode.XYXY_ABS)
if len(x["bbox"]) == 4
else x["bbox"]
for x in annos
]
colors = None
category_ids = [x["category_id"] for x in annos]
if self._instance_mode == ColorMode.SEGMENTATION and self.metadata.get("thing_colors"):
colors = [
self._jitter([x / 255 for x in self.metadata.thing_colors[c]])
for c in category_ids
]
names = self.metadata.get("thing_classes", None)
labels = _create_text_labels(
category_ids,
scores=None,
class_names=names,
is_crowd=[x.get("iscrowd", 0) for x in annos],
)
self.overlay_instances(
labels=labels, boxes=boxes, masks=masks, keypoints=keypts, assigned_colors=colors
)
sem_seg = dic.get("sem_seg", None)
if sem_seg is None and "sem_seg_file_name" in dic:
with PathManager.open(dic["sem_seg_file_name"], "rb") as f:
sem_seg = Image.open(f)
sem_seg = np.asarray(sem_seg, dtype="uint8")
if sem_seg is not None:
self.draw_sem_seg(sem_seg, area_threshold=0, alpha=0.5)
pan_seg = dic.get("pan_seg", None)
if pan_seg is None and "pan_seg_file_name" in dic:
with PathManager.open(dic["pan_seg_file_name"], "rb") as f:
pan_seg = Image.open(f)
pan_seg = np.asarray(pan_seg)
from panopticapi.utils import rgb2id
pan_seg = rgb2id(pan_seg)
if pan_seg is not None:
segments_info = dic["segments_info"]
pan_seg = torch.tensor(pan_seg)
self.draw_panoptic_seg(pan_seg, segments_info, area_threshold=0, alpha=0.5)
return self.output[docs] def overlay_instances(
self,
*,
boxes=None,
labels=None,
masks=None,
keypoints=None,
assigned_colors=None,
alpha=0.5,
):
"""
Args:
boxes (Boxes, RotatedBoxes or ndarray): either a :class:Boxes,
or an Nx4 numpy array of XYXY_ABS format for the N objects in a single image,
or a :class:RotatedBoxes,
or an Nx5 numpy array of (x_center, y_center, width, height, angle_degrees) format
for the N objects in a single image,
labels (list[str]): the text to be displayed for each instance.
masks (masks-like object): Supported types are:
* :class:`detectron2.structures.PolygonMasks`,
:class:`detectron2.structures.BitMasks`.
* list[list[ndarray]]: contains the segmentation masks for all objects in one image.
The first level of the list corresponds to individual instances. The second
level to all the polygon that compose the instance, and the third level
to the polygon coordinates. The third level should have the format of
[x0, y0, x1, y1, ..., xn, yn] (n >= 3).
* list[ndarray]: each ndarray is a binary mask of shape (H, W).
* list[dict]: each dict is a COCO-style RLE.
keypoints (Keypoint or array like): an array-like object of shape (N, K, 3),
where the N is the number of instances and K is the number of keypoints.
The last dimension corresponds to (x, y, visibility or score).
assigned_colors (list[matplotlib.colors]): a list of colors, where each color
corresponds to each mask or box in the image. Refer to 'matplotlib.colors'
for full list of formats that the colors are accepted in.
Returns:
output (VisImage): image object with visualizations.
"""
num_instances = 0
if boxes is not None:
boxes = self._convert_boxes(boxes)
num_instances = len(boxes)
if masks is not None:
masks = self._convert_masks(masks)
if num_instances:
assert len(masks) == num_instances
else:
num_instances = len(masks)
if keypoints is not None:
if num_instances:
assert len(keypoints) == num_instances
else:
num_instances = len(keypoints)
keypoints = self._convert_keypoints(keypoints)
if labels is not None:
assert len(labels) == num_instances
if assigned_colors is None:
assigned_colors = [random_color(rgb=True, maximum=1) for _ in range(num_instances)]
if num_instances == 0:
return self.output
if boxes is not None and boxes.shape[1] == 5:
return self.overlay_rotated_instances(
boxes=boxes, labels=labels, assigned_colors=assigned_colors
)
# Display in largest to smallest order to reduce occlusion.
areas = None
if boxes is not None:
areas = np.prod(boxes[:, 2:] - boxes[:, :2], axis=1)
elif masks is not None:
areas = np.asarray([x.area() for x in masks])
if areas is not None:
sorted_idxs = np.argsort(-areas).tolist()
# Re-order overlapped instances in descending order.
boxes = boxes[sorted_idxs] if boxes is not None else None
labels = [labels[k] for k in sorted_idxs] if labels is not None else None
masks = [masks[idx] for idx in sorted_idxs] if masks is not None else None
assigned_colors = [assigned_colors[idx] for idx in sorted_idxs]
keypoints = keypoints[sorted_idxs] if keypoints is not None else None
for i in range(num_instances):
color = assigned_colors[i]
if boxes is not None:
self.draw_box(boxes[i], edge_color=color)
if masks is not None:
for segment in masks[i].polygons:
self.draw_polygon(segment.reshape(-1, 2), color, alpha=alpha)
if labels is not None:
# first get a box
if boxes is not None:
x0, y0, x1, y1 = boxes[i]
text_pos = (x0, y0) # if drawing boxes, put text on the box corner.
horiz_align = "left"
elif masks is not None:
# skip small mask without polygon
if len(masks[i].polygons) == 0:
continue
x0, y0, x1, y1 = masks[i].bbox()
# draw text in the center (defined by median) when box is not drawn
# median is less sensitive to outliers.
text_pos = np.median(masks[i].mask.nonzero(), axis=1)[::-1]
horiz_align = "center"
else:
continue # drawing the box confidence for keypoints isn't very useful.
# for small objects, draw text at the side to avoid occlusion
instance_area = (y1 - y0) * (x1 - x0)
if (
instance_area < _SMALL_OBJECT_AREA_THRESH * self.output.scale
or y1 - y0 < 40 * self.output.scale
):
if y1 >= self.output.height - 5:
text_pos = (x1, y0)
else:
text_pos = (x0, y1)
height_ratio = (y1 - y0) / np.sqrt(self.output.height * self.output.width)
lighter_color = self._change_color_brightness(color, brightness_factor=0.7)
font_size = (
np.clip((height_ratio - 0.02) / 0.08 + 1, 1.2, 2)
* 0.5
* self._default_font_size
)
self.draw_text(
labels[i],
text_pos,
color=lighter_color,
horizontal_alignment=horiz_align,
font_size=font_size,
)
# draw keypoints
if keypoints is not None:
for keypoints_per_instance in keypoints:
self.draw_and_connect_keypoints(keypoints_per_instance)
return self.output[docs] def overlay_rotated_instances(self, boxes=None, labels=None, assigned_colors=None): """ Args: boxes (ndarray): an Nx5 numpy array of (x_center, y_center, width, height, angle_degrees) format for the N objects in a single image. labels (list[str]): the text to be displayed for each instance. assigned_colors (list[matplotlib.colors]): a list of colors, where each color corresponds to each mask or box in the image. Refer to 'matplotlib.colors' for full list of formats that the colors are accepted in.
Returns:
output (VisImage): image object with visualizations.
"""
num_instances = len(boxes)
if assigned_colors is None:
assigned_colors = [random_color(rgb=True, maximum=1) for _ in range(num_instances)]
if num_instances == 0:
return self.output
# Display in largest to smallest order to reduce occlusion.
if boxes is not None:
areas = boxes[:, 2] * boxes[:, 3]
sorted_idxs = np.argsort(-areas).tolist()
# Re-order overlapped instances in descending order.
boxes = boxes[sorted_idxs]
labels = [labels[k] for k in sorted_idxs] if labels is not None else None
colors = [assigned_colors[idx] for idx in sorted_idxs]
for i in range(num_instances):
self.draw_rotated_box_with_label(
boxes[i], edge_color=colors[i], label=labels[i] if labels is not None else None
)
return self.output[docs] def draw_and_connect_keypoints(self, keypoints): """ Draws keypoints of an instance and follows the rules for keypoint connections to draw lines between appropriate keypoints. This follows color heuristics for line color.
Args:
keypoints (Tensor): a tensor of shape (K, 3), where K is the number of keypoints
and the last dimension corresponds to (x, y, probability).
Returns:
output (VisImage): image object with visualizations.
"""
visible = {}
keypoint_names = self.metadata.get("keypoint_names")
for idx, keypoint in enumerate(keypoints):
# draw keypoint
x, y, prob = keypoint
if prob > self.keypoint_threshold:
self.draw_circle((x, y), color=_RED)
if keypoint_names:
keypoint_name = keypoint_names[idx]
visible[keypoint_name] = (x, y)
if self.metadata.get("keypoint_connection_rules"):
for kp0, kp1, color in self.metadata.keypoint_connection_rules:
if kp0 in visible and kp1 in visible:
x0, y0 = visible[kp0]
x1, y1 = visible[kp1]
color = tuple(x / 255.0 for x in color)
self.draw_line([x0, x1], [y0, y1], color=color)
# draw lines from nose to mid-shoulder and mid-shoulder to mid-hip
# Note that this strategy is specific to person keypoints.
# For other keypoints, it should just do nothing
try:
ls_x, ls_y = visible["left_shoulder"]
rs_x, rs_y = visible["right_shoulder"]
mid_shoulder_x, mid_shoulder_y = (ls_x + rs_x) / 2, (ls_y + rs_y) / 2
except KeyError:
pass
else:
# draw line from nose to mid-shoulder
nose_x, nose_y = visible.get("nose", (None, None))
if nose_x is not None:
self.draw_line([nose_x, mid_shoulder_x], [nose_y, mid_shoulder_y], color=_RED)
try:
# draw line from mid-shoulder to mid-hip
lh_x, lh_y = visible["left_hip"]
rh_x, rh_y = visible["right_hip"]
except KeyError:
pass
else:
mid_hip_x, mid_hip_y = (lh_x + rh_x) / 2, (lh_y + rh_y) / 2
self.draw_line([mid_hip_x, mid_shoulder_x], [mid_hip_y, mid_shoulder_y], color=_RED)
return self.output
"""
Primitive drawing functions:
"""[docs] def draw_text(
self,
text,
position,
*,
font_size=None,
color="g",
horizontal_alignment="center",
rotation=0,
):
"""
Args:
text (str): class label
position (tuple): a tuple of the x and y coordinates to place text on image.
font_size (int, optional): font of the text. If not provided, a font size
proportional to the image width is calculated and used.
color: color of the text. Refer to matplotlib.colors for full list
of formats that are accepted.
horizontal_alignment (str): see matplotlib.text.Text
rotation: rotation angle in degrees CCW
Returns:
output (VisImage): image object with text drawn.
"""
if not font_size:
font_size = self._default_font_size
# since the text background is dark, we don't want the text to be dark
color = np.maximum(list(mplc.to_rgb(color)), 0.2)
color[np.argmax(color)] = max(0.8, np.max(color))
x, y = position
self.output.ax.text(
x,
y,
text,
size=font_size * self.output.scale,
family="sans-serif",
bbox={"facecolor": "black", "alpha": 0.8, "pad": 0.7, "edgecolor": "none"},
verticalalignment="top",
horizontalalignment=horizontal_alignment,
color=color,
zorder=10,
rotation=rotation,
)
return self.output[docs] def draw_box(self, box_coord, alpha=0.5, edge_color="g", line_style="-"):
"""
Args:
box_coord (tuple): a tuple containing x0, y0, x1, y1 coordinates, where x0 and y0
are the coordinates of the image's top left corner. x1 and y1 are the
coordinates of the image's bottom right corner.
alpha (float): blending efficient. Smaller values lead to more transparent masks.
edge_color: color of the outline of the box. Refer to matplotlib.colors
for full list of formats that are accepted.
line_style (string): the string to use to create the outline of the boxes.
Returns:
output (VisImage): image object with box drawn.
"""
x0, y0, x1, y1 = box_coord
width = x1 - x0
height = y1 - y0
linewidth = max(self._default_font_size / 4, 1)
self.output.ax.add_patch(
mpl.patches.Rectangle(
(x0, y0),
width,
height,
fill=False,
edgecolor=edge_color,
linewidth=linewidth * self.output.scale,
alpha=alpha,
linestyle=line_style,
)
)
return self.output[docs] def draw_rotated_box_with_label( self, rotated_box, alpha=0.5, edge_color="g", line_style="-", label=None ): """ Draw a rotated box with label on its top-left corner.
Args:
rotated_box (tuple): a tuple containing (cnt_x, cnt_y, w, h, angle),
where cnt_x and cnt_y are the center coordinates of the box.
w and h are the width and height of the box. angle represents how
many degrees the box is rotated CCW with regard to the 0-degree box.
alpha (float): blending efficient. Smaller values lead to more transparent masks.
edge_color: color of the outline of the box. Refer to `matplotlib.colors`
for full list of formats that are accepted.
line_style (string): the string to use to create the outline of the boxes.
label (string): label for rotated box. It will not be rendered when set to None.
Returns:
output (VisImage): image object with box drawn.
"""
cnt_x, cnt_y, w, h, angle = rotated_box
area = w * h
# use thinner lines when the box is small
linewidth = self._default_font_size / (
6 if area < _SMALL_OBJECT_AREA_THRESH * self.output.scale else 3
)
theta = angle * math.pi / 180.0
c = math.cos(theta)
s = math.sin(theta)
rect = [(-w / 2, h / 2), (-w / 2, -h / 2), (w / 2, -h / 2), (w / 2, h / 2)]
# x: left->right ; y: top->down
rotated_rect = [(s * yy + c * xx + cnt_x, c * yy - s * xx + cnt_y) for (xx, yy) in rect]
for k in range(4):
j = (k + 1) % 4
self.draw_line(
[rotated_rect[k][0], rotated_rect[j][0]],
[rotated_rect[k][1], rotated_rect[j][1]],
color=edge_color,
linestyle="--" if k == 1 else line_style,
linewidth=linewidth,
)
if label is not None:
text_pos = rotated_rect[1] # topleft corner
height_ratio = h / np.sqrt(self.output.height * self.output.width)
label_color = self._change_color_brightness(edge_color, brightness_factor=0.7)
font_size = (
np.clip((height_ratio - 0.02) / 0.08 + 1, 1.2, 2) * 0.5 * self._default_font_size
)
self.draw_text(label, text_pos, color=label_color, font_size=font_size, rotation=angle)
return self.output[docs] def draw_circle(self, circle_coord, color, radius=3):
"""
Args:
circle_coord (list(int) or tuple(int)): contains the x and y coordinates
of the center of the circle.
color: color of the polygon. Refer to matplotlib.colors for a full list of
formats that are accepted.
radius (int): radius of the circle.
Returns:
output (VisImage): image object with box drawn.
"""
x, y = circle_coord
self.output.ax.add_patch(
mpl.patches.Circle(circle_coord, radius=radius, fill=True, color=color)
)
return self.output[docs] def draw_line(self, x_data, y_data, color, linestyle="-", linewidth=None):
"""
Args:
x_data (list[int]): a list containing x values of all the points being drawn.
Length of list should match the length of y_data.
y_data (list[int]): a list containing y values of all the points being drawn.
Length of list should match the length of x_data.
color: color of the line. Refer to matplotlib.colors for a full list of
formats that are accepted.
linestyle: style of the line. Refer to matplotlib.lines.Line2D
for a full list of formats that are accepted.
linewidth (float or None): width of the line. When it's None,
a default value will be computed and used.
Returns:
output (VisImage): image object with line drawn.
"""
if linewidth is None:
linewidth = self._default_font_size / 3
linewidth = max(linewidth, 1)
self.output.ax.add_line(
mpl.lines.Line2D(
x_data,
y_data,
linewidth=linewidth * self.output.scale,
color=color,
linestyle=linestyle,
)
)
return self.output[docs] def draw_binary_mask(
self, binary_mask, color=None, *, edge_color=None, text=None, alpha=0.5, area_threshold=10
):
"""
Args:
binary_mask (ndarray): numpy array of shape (H, W), where H is the image height and
W is the image width. Each value in the array is either a 0 or 1 value of uint8
type.
color: color of the mask. Refer to matplotlib.colors for a full list of
formats that are accepted. If None, will pick a random color.
edge_color: color of the polygon edges. Refer to matplotlib.colors for a
full list of formats that are accepted.
text (str): if None, will be drawn on the object
alpha (float): blending efficient. Smaller values lead to more transparent masks.
area_threshold (float): a connected component smaller than this area will not be shown.
Returns:
output (VisImage): image object with mask drawn.
"""
if color is None:
color = random_color(rgb=True, maximum=1)
color = mplc.to_rgb(color)
has_valid_segment = False
binary_mask = binary_mask.astype("uint8") # opencv needs uint8
mask = GenericMask(binary_mask, self.output.height, self.output.width)
shape2d = (binary_mask.shape[0], binary_mask.shape[1])
if not mask.has_holes:
# draw polygons for regular masks
for segment in mask.polygons:
area = mask_util.area(mask_util.frPyObjects([segment], shape2d[0], shape2d[1]))
if area < (area_threshold or 0):
continue
has_valid_segment = True
segment = segment.reshape(-1, 2)
self.draw_polygon(segment, color=color, edge_color=edge_color, alpha=alpha)
else:
# TODO: Use Path/PathPatch to draw vector graphics:
# https://stackoverflow.com/questions/8919719/how-to-plot-a-complex-polygon
rgba = np.zeros(shape2d + (4,), dtype="float32")
rgba[:, :, :3] = color
rgba[:, :, 3] = (mask.mask == 1).astype("float32") * alpha
has_valid_segment = True
self.output.ax.imshow(rgba, extent=(0, self.output.width, self.output.height, 0))
if text is not None and has_valid_segment:
lighter_color = self._change_color_brightness(color, brightness_factor=0.7)
self._draw_text_in_mask(binary_mask, text, lighter_color)
return self.output[docs] def draw_soft_mask(self, soft_mask, color=None, *, text=None, alpha=0.5):
"""
Args:
soft_mask (ndarray): float array of shape (H, W), each value in [0, 1].
color: color of the mask. Refer to matplotlib.colors for a full list of
formats that are accepted. If None, will pick a random color.
text (str): if None, will be drawn on the object
alpha (float): blending efficient. Smaller values lead to more transparent masks.
Returns:
output (VisImage): image object with mask drawn.
"""
if color is None:
color = random_color(rgb=True, maximum=1)
color = mplc.to_rgb(color)
shape2d = (soft_mask.shape[0], soft_mask.shape[1])
rgba = np.zeros(shape2d + (4,), dtype="float32")
rgba[:, :, :3] = color
rgba[:, :, 3] = soft_mask * alpha
self.output.ax.imshow(rgba, extent=(0, self.output.width, self.output.height, 0))
if text is not None:
lighter_color = self._change_color_brightness(color, brightness_factor=0.7)
binary_mask = (soft_mask > 0.5).astype("uint8")
self._draw_text_in_mask(binary_mask, text, lighter_color)
return self.output[docs] def draw_polygon(self, segment, color, edge_color=None, alpha=0.5):
"""
Args:
segment: numpy array of shape Nx2, containing all the points in the polygon.
color: color of the polygon. Refer to matplotlib.colors for a full list of
formats that are accepted.
edge_color: color of the polygon edges. Refer to matplotlib.colors for a
full list of formats that are accepted. If not provided, a darker shade
of the polygon color will be used instead.
alpha (float): blending efficient. Smaller values lead to more transparent masks.
Returns:
output (VisImage): image object with polygon drawn.
"""
if edge_color is None:
# make edge color darker than the polygon color
if alpha > 0.8:
edge_color = self._change_color_brightness(color, brightness_factor=-0.7)
else:
edge_color = color
edge_color = mplc.to_rgb(edge_color) + (1,)
polygon = mpl.patches.Polygon(
segment,
fill=True,
facecolor=mplc.to_rgb(color) + (alpha,),
edgecolor=edge_color,
linewidth=max(self._default_font_size // 15 * self.output.scale, 1),
)
self.output.ax.add_patch(polygon)
return self.output
"""
Internal methods:
"""
def _jitter(self, color):
"""
Randomly modifies given color to produce a slightly different color than the color given.
Args:
color (tuple[double]): a tuple of 3 elements, containing the RGB values of the color
picked. The values in the list are in the [0.0, 1.0] range.
Returns:
jittered_color (tuple[double]): a tuple of 3 elements, containing the RGB values of the
color after being jittered. The values in the list are in the [0.0, 1.0] range.
"""
color = mplc.to_rgb(color)
vec = np.random.rand(3)
# better to do it in another color space
vec = vec / np.linalg.norm(vec) * 0.5
res = np.clip(vec + color, 0, 1)
return tuple(res)
def _create_grayscale_image(self, mask=None):
"""
Create a grayscale version of the original image.
The colors in masked area, if given, will be kept.
"""
img_bw = self.img.astype("f4").mean(axis=2)
img_bw = np.stack([img_bw] * 3, axis=2)
if mask is not None:
img_bw[mask] = self.img[mask]
return img_bw
def _change_color_brightness(self, color, brightness_factor):
"""
Depending on the brightness_factor, gives a lighter or darker color i.e. a color with
less or more saturation than the original color.
Args:
color: color of the polygon. Refer to `matplotlib.colors` for a full list of
formats that are accepted.
brightness_factor (float): a value in [-1.0, 1.0] range. A lightness factor of
0 will correspond to no change, a factor in [-1.0, 0) range will result in
a darker color and a factor in (0, 1.0] range will result in a lighter color.
Returns:
modified_color (tuple[double]): a tuple containing the RGB values of the
modified color. Each value in the tuple is in the [0.0, 1.0] range.
"""
assert brightness_factor >= -1.0 and brightness_factor <= 1.0
color = mplc.to_rgb(color)
polygon_color = colorsys.rgb_to_hls(*mplc.to_rgb(color))
modified_lightness = polygon_color[1] + (brightness_factor * polygon_color[1])
modified_lightness = 0.0 if modified_lightness < 0.0 else modified_lightness
modified_lightness = 1.0 if modified_lightness > 1.0 else modified_lightness
modified_color = colorsys.hls_to_rgb(polygon_color[0], modified_lightness, polygon_color[2])
return tuple(np.clip(modified_color, 0.0, 1.0))
def _convert_boxes(self, boxes):
"""
Convert different format of boxes to an NxB array, where B = 4 or 5 is the box dimension.
"""
if isinstance(boxes, Boxes) or isinstance(boxes, RotatedBoxes):
return boxes.tensor.detach().numpy()
else:
return np.asarray(boxes)
def _convert_masks(self, masks_or_polygons):
"""
Convert different format of masks or polygons to a tuple of masks and polygons.
Returns:
list[GenericMask]:
"""
m = masks_or_polygons
if isinstance(m, PolygonMasks):
m = m.polygons
if isinstance(m, BitMasks):
m = m.tensor.numpy()
if isinstance(m, torch.Tensor):
m = m.numpy()
ret = []
for x in m:
if isinstance(x, GenericMask):
ret.append(x)
else:
ret.append(GenericMask(x, self.output.height, self.output.width))
return ret
def _draw_text_in_mask(self, binary_mask, text, color):
"""
Find proper places to draw text given a binary mask.
"""
# TODO sometimes drawn on wrong objects. the heuristics here can improve.
_num_cc, cc_labels, stats, centroids = cv2.connectedComponentsWithStats(binary_mask, 8)
if stats[1:, -1].size == 0:
return
largest_component_id = np.argmax(stats[1:, -1]) + 1
# draw text on the largest component, as well as other very large components.
for cid in range(1, _num_cc):
if cid == largest_component_id or stats[cid, -1] > _LARGE_MASK_AREA_THRESH:
# median is more stable than centroid
# center = centroids[largest_component_id]
center = np.median((cc_labels == cid).nonzero(), axis=1)[::-1]
self.draw_text(text, center, color=color)
def _convert_keypoints(self, keypoints):
if isinstance(keypoints, Keypoints):
keypoints = keypoints.tensor
keypoints = np.asarray(keypoints)
return keypoints[docs] def get_output(self): """ Returns: output (VisImage): the image output containing the visualizations added to the image. """ return self.output