# Copyright (c) OpenMMLab. All rights reserved.
from typing import List, Optional, Union
import cv2
import mmcv
import numpy as np
import torch
from mmengine.dist import master_only
from mmengine.visualization import Visualizer
class OpencvBackendVisualizer(Visualizer):
"""Base visualizer with opencv backend support.
Args:
name (str): Name of the instance. Defaults to 'visualizer'.
image (np.ndarray, optional): the origin image to draw. The format
should be RGB. Defaults to None.
vis_backends (list, optional): Visual backend config list.
Defaults to None.
save_dir (str, optional): Save file dir for all storage backends.
If it is None, the backend storage will not save any data.
fig_save_cfg (dict): Keyword parameters of figure for saving.
Defaults to empty dict.
fig_show_cfg (dict): Keyword parameters of figure for showing.
Defaults to empty dict.
backend (str): Backend used to draw elements on the image and display
the image. Defaults to 'matplotlib'.
"""
def __init__(self,
name='visualizer',
backend: str = 'matplotlib',
*args,
**kwargs):
super().__init__(name, *args, **kwargs)
assert backend in ('opencv', 'matplotlib'), f'the argument ' \
f'\'backend\' must be either \'opencv\' or \'matplotlib\', ' \
f'but got \'{backend}\'.'
self.backend = backend
@master_only
def set_image(self, image: np.ndarray) -> None:
"""Set the image to draw.
Args:
image (np.ndarray): The image to draw.
backend (str): The backend to save the image.
"""
assert image is not None
image = image.astype('uint8')
self._image = image
self.width, self.height = image.shape[1], image.shape[0]
self._default_font_size = max(
np.sqrt(self.height * self.width) // 90, 10)
if self.backend == 'matplotlib':
# add a small 1e-2 to avoid precision lost due to matplotlib's
# truncation (https://github.com/matplotlib/matplotlib/issues/15363) # noqa
self.fig_save.set_size_inches( # type: ignore
(self.width + 1e-2) / self.dpi,
(self.height + 1e-2) / self.dpi)
# self.canvas = mpl.backends.backend_cairo.FigureCanvasCairo(fig)
self.ax_save.cla()
self.ax_save.axis(False)
self.ax_save.imshow(
image,
extent=(0, self.width, self.height, 0),
interpolation='none')
@master_only
def get_image(self) -> np.ndarray:
"""Get the drawn image. The format is RGB.
Returns:
np.ndarray: the drawn image which channel is RGB.
"""
assert self._image is not None, 'Please set image using `set_image`'
if self.backend == 'matplotlib':
return super().get_image()
else:
return self._image
@master_only
def draw_circles(self,
center: Union[np.ndarray, torch.Tensor],
radius: Union[np.ndarray, torch.Tensor],
face_colors: Union[str, tuple, List[str],
List[tuple]] = 'none',
**kwargs) -> 'Visualizer':
"""Draw single or multiple circles.
Args:
center (Union[np.ndarray, torch.Tensor]): The x coordinate of
each line' start and end points.
radius (Union[np.ndarray, torch.Tensor]): The y coordinate of
each line' start and end points.
edge_colors (Union[str, tuple, List[str], List[tuple]]): The
colors of circles. ``colors`` can have the same length with
lines or just single value. If ``colors`` is single value,
all the lines will have the same colors. Reference to
https://matplotlib.org/stable/gallery/color/named_colors.html
for more details. Defaults to 'g.
line_styles (Union[str, List[str]]): The linestyle
of lines. ``line_styles`` can have the same length with
texts or just single value. If ``line_styles`` is single
value, all the lines will have the same linestyle.
Reference to
https://matplotlib.org/stable/api/collections_api.html?highlight=collection#matplotlib.collections.AsteriskPolygonCollection.set_linestyle
for more details. Defaults to '-'.
line_widths (Union[Union[int, float], List[Union[int, float]]]):
The linewidth of lines. ``line_widths`` can have
the same length with lines or just single value.
If ``line_widths`` is single value, all the lines will
have the same linewidth. Defaults to 2.
face_colors (Union[str, tuple, List[str], List[tuple]]):
The face colors. Defaults to None.
alpha (Union[int, float]): The transparency of circles.
Defaults to 0.8.
"""
if self.backend == 'matplotlib':
super().draw_circles(
center=center,
radius=radius,
face_colors=face_colors,
**kwargs)
elif self.backend == 'opencv':
if isinstance(face_colors, str):
face_colors = mmcv.color_val(face_colors)
self._image = cv2.circle(self._image,
(int(center[0]), int(center[1])),
int(radius), face_colors, -1)
else:
raise ValueError(f'got unsupported backend {self.backend}')
@master_only
def draw_texts(
self,
texts: Union[str, List[str]],
positions: Union[np.ndarray, torch.Tensor],
font_sizes: Optional[Union[int, List[int]]] = None,
colors: Union[str, tuple, List[str], List[tuple]] = 'g',
vertical_alignments: Union[str, List[str]] = 'top',
horizontal_alignments: Union[str, List[str]] = 'left',
bboxes: Optional[Union[dict, List[dict]]] = None,
**kwargs,
) -> 'Visualizer':
"""Draw single or multiple text boxes.
Args:
texts (Union[str, List[str]]): Texts to draw.
positions (Union[np.ndarray, torch.Tensor]): The position to draw
the texts, which should have the same length with texts and
each dim contain x and y.
font_sizes (Union[int, List[int]], optional): The font size of
texts. ``font_sizes`` can have the same length with texts or
just single value. If ``font_sizes`` is single value, all the
texts will have the same font size. Defaults to None.
colors (Union[str, tuple, List[str], List[tuple]]): The colors
of texts. ``colors`` can have the same length with texts or
just single value. If ``colors`` is single value, all the
texts will have the same colors. Reference to
https://matplotlib.org/stable/gallery/color/named_colors.html
for more details. Defaults to 'g.
vertical_alignments (Union[str, List[str]]): The verticalalignment
of texts. verticalalignment controls whether the y positional
argument for the text indicates the bottom, center or top side
of the text bounding box.
``vertical_alignments`` can have the same length with
texts or just single value. If ``vertical_alignments`` is
single value, all the texts will have the same
verticalalignment. verticalalignment can be 'center' or
'top', 'bottom' or 'baseline'. Defaults to 'top'.
horizontal_alignments (Union[str, List[str]]): The
horizontalalignment of texts. Horizontalalignment controls
whether the x positional argument for the text indicates the
left, center or right side of the text bounding box.
``horizontal_alignments`` can have
the same length with texts or just single value.
If ``horizontal_alignments`` is single value, all the texts
will have the same horizontalalignment. Horizontalalignment
can be 'center','right' or 'left'. Defaults to 'left'.
font_families (Union[str, List[str]]): The font family of
texts. ``font_families`` can have the same length with texts or
just single value. If ``font_families`` is single value, all
the texts will have the same font family.
font_familiy can be 'serif', 'sans-serif', 'cursive', 'fantasy'
or 'monospace'. Defaults to 'sans-serif'.
bboxes (Union[dict, List[dict]], optional): The bounding box of the
texts. If bboxes is None, there are no bounding box around
texts. ``bboxes`` can have the same length with texts or
just single value. If ``bboxes`` is single value, all
the texts will have the same bbox. Reference to
https://matplotlib.org/stable/api/_as_gen/matplotlib.patches.FancyBboxPatch.html#matplotlib.patches.FancyBboxPatch
for more details. Defaults to None.
font_properties (Union[FontProperties, List[FontProperties]], optional):
The font properties of texts. FontProperties is
a ``font_manager.FontProperties()`` object.
If you want to draw Chinese texts, you need to prepare
a font file that can show Chinese characters properly.
For example: `simhei.ttf`, `simsun.ttc`, `simkai.ttf` and so on.
Then set ``font_properties=matplotlib.font_manager.FontProperties(fname='path/to/font_file')``
``font_properties`` can have the same length with texts or
just single value. If ``font_properties`` is single value,
all the texts will have the same font properties.
Defaults to None.
`New in version 0.6.0.`
""" # noqa: E501
if self.backend == 'matplotlib':
super().draw_texts(
texts=texts,
positions=positions,
font_sizes=font_sizes,
colors=colors,
vertical_alignments=vertical_alignments,
horizontal_alignments=horizontal_alignments,
bboxes=bboxes,
**kwargs)
elif self.backend == 'opencv':
font_scale = max(0.1, font_sizes / 30)
thickness = max(1, font_sizes // 15)
text_size, text_baseline = cv2.getTextSize(texts,
cv2.FONT_HERSHEY_DUPLEX,
font_scale, thickness)
x = int(positions[0])
if horizontal_alignments == 'right':
x = max(0, x - text_size[0])
y = int(positions[1])
if vertical_alignments == 'top':
y = min(self.height, y + text_size[1])
if bboxes is not None:
bbox_color = bboxes[0]['facecolor']
if isinstance(bbox_color, str):
bbox_color = mmcv.color_val(bbox_color)
y = y - text_baseline // 2
self._image = cv2.rectangle(
self._image, (x, y - text_size[1] - text_baseline // 2),
(x + text_size[0], y + text_baseline // 2), bbox_color,
cv2.FILLED)
self._image = cv2.putText(self._image, texts, (x, y),
cv2.FONT_HERSHEY_SIMPLEX, font_scale,
colors, thickness - 1)
else:
raise ValueError(f'got unsupported backend {self.backend}')
@master_only
def draw_bboxes(self,
bboxes: Union[np.ndarray, torch.Tensor],
edge_colors: Union[str, tuple, List[str],
List[tuple]] = 'g',
line_widths: Union[Union[int, float],
List[Union[int, float]]] = 2,
**kwargs) -> 'Visualizer':
"""Draw single or multiple bboxes.
Args:
bboxes (Union[np.ndarray, torch.Tensor]): The bboxes to draw with
the format of(x1,y1,x2,y2).
edge_colors (Union[str, tuple, List[str], List[tuple]]): The
colors of bboxes. ``colors`` can have the same length with
lines or just single value. If ``colors`` is single value, all
the lines will have the same colors. Refer to `matplotlib.
colors` for full list of formats that are accepted.
Defaults to 'g'.
line_styles (Union[str, List[str]]): The linestyle
of lines. ``line_styles`` can have the same length with
texts or just single value. If ``line_styles`` is single
value, all the lines will have the same linestyle.
Reference to
https://matplotlib.org/stable/api/collections_api.html?highlight=collection#matplotlib.collections.AsteriskPolygonCollection.set_linestyle
for more details. Defaults to '-'.
line_widths (Union[Union[int, float], List[Union[int, float]]]):
The linewidth of lines. ``line_widths`` can have
the same length with lines or just single value.
If ``line_widths`` is single value, all the lines will
have the same linewidth. Defaults to 2.
face_colors (Union[str, tuple, List[str], List[tuple]]):
The face colors. Defaults to None.
alpha (Union[int, float]): The transparency of bboxes.
Defaults to 0.8.
"""
if self.backend == 'matplotlib':
super().draw_bboxes(
bboxes=bboxes,
edge_colors=edge_colors,
line_widths=line_widths,
**kwargs)
elif self.backend == 'opencv':
self._image = mmcv.imshow_bboxes(
self._image,
bboxes,
edge_colors,
top_k=-1,
thickness=line_widths,
show=False)
else:
raise ValueError(f'got unsupported backend {self.backend}')
@master_only
def draw_lines(self,
x_datas: Union[np.ndarray, torch.Tensor],
y_datas: Union[np.ndarray, torch.Tensor],
colors: Union[str, tuple, List[str], List[tuple]] = 'g',
line_widths: Union[Union[int, float],
List[Union[int, float]]] = 2,
**kwargs) -> 'Visualizer':
"""Draw single or multiple line segments.
Args:
x_datas (Union[np.ndarray, torch.Tensor]): The x coordinate of
each line' start and end points.
y_datas (Union[np.ndarray, torch.Tensor]): The y coordinate of
each line' start and end points.
colors (Union[str, tuple, List[str], List[tuple]]): The colors of
lines. ``colors`` can have the same length with lines or just
single value. If ``colors`` is single value, all the lines
will have the same colors. Reference to
https://matplotlib.org/stable/gallery/color/named_colors.html
for more details. Defaults to 'g'.
line_styles (Union[str, List[str]]): The linestyle
of lines. ``line_styles`` can have the same length with
texts or just single value. If ``line_styles`` is single
value, all the lines will have the same linestyle.
Reference to
https://matplotlib.org/stable/api/collections_api.html?highlight=collection#matplotlib.collections.AsteriskPolygonCollection.set_linestyle
for more details. Defaults to '-'.
line_widths (Union[Union[int, float], List[Union[int, float]]]):
The linewidth of lines. ``line_widths`` can have
the same length with lines or just single value.
If ``line_widths`` is single value, all the lines will
have the same linewidth. Defaults to 2.
"""
if self.backend == 'matplotlib':
super().draw_lines(
x_datas=x_datas,
y_datas=y_datas,
colors=colors,
line_widths=line_widths,
**kwargs)
elif self.backend == 'opencv':
self._image = cv2.line(
self._image, (x_datas[0], y_datas[0]),
(x_datas[1], y_datas[1]),
colors,
thickness=line_widths)
else:
raise ValueError(f'got unsupported backend {self.backend}')
@master_only
def draw_polygons(self,
polygons: Union[Union[np.ndarray, torch.Tensor],
List[Union[np.ndarray, torch.Tensor]]],
edge_colors: Union[str, tuple, List[str],
List[tuple]] = 'g',
**kwargs) -> 'Visualizer':
"""Draw single or multiple bboxes.
Args:
polygons (Union[Union[np.ndarray, torch.Tensor],\
List[Union[np.ndarray, torch.Tensor]]]): The polygons to draw
with the format of (x1,y1,x2,y2,...,xn,yn).
edge_colors (Union[str, tuple, List[str], List[tuple]]): The
colors of polygons. ``colors`` can have the same length with
lines or just single value. If ``colors`` is single value,
all the lines will have the same colors. Refer to
`matplotlib.colors` for full list of formats that are accepted.
Defaults to 'g.
line_styles (Union[str, List[str]]): The linestyle
of lines. ``line_styles`` can have the same length with
texts or just single value. If ``line_styles`` is single
value, all the lines will have the same linestyle.
Reference to
https://matplotlib.org/stable/api/collections_api.html?highlight=collection#matplotlib.collections.AsteriskPolygonCollection.set_linestyle
for more details. Defaults to '-'.
line_widths (Union[Union[int, float], List[Union[int, float]]]):
The linewidth of lines. ``line_widths`` can have
the same length with lines or just single value.
If ``line_widths`` is single value, all the lines will
have the same linewidth. Defaults to 2.
face_colors (Union[str, tuple, List[str], List[tuple]]):
The face colors. Defaults to None.
alpha (Union[int, float]): The transparency of polygons.
Defaults to 0.8.
"""
if self.backend == 'matplotlib':
super().draw_polygons(
polygons=polygons, edge_colors=edge_colors, **kwargs)
elif self.backend == 'opencv':
self._image = cv2.fillConvexPoly(self._image, polygons,
edge_colors)
else:
raise ValueError(f'got unsupported backend {self.backend}')
@master_only
def show(self,
drawn_img: Optional[np.ndarray] = None,
win_name: str = 'image',
wait_time: float = 0.,
continue_key=' ') -> None:
"""Show the drawn image.
Args:
drawn_img (np.ndarray, optional): The image to show. If drawn_img
is None, it will show the image got by Visualizer. Defaults
to None.
win_name (str): The image title. Defaults to 'image'.
wait_time (float): Delay in seconds. 0 is the special
value that means "forever". Defaults to 0.
continue_key (str): The key for users to continue. Defaults to
the space key.
"""
if self.backend == 'matplotlib':
super().show(
drawn_img=drawn_img,
win_name=win_name,
wait_time=wait_time,
continue_key=continue_key)
elif self.backend == 'opencv':
# Keep images are shown in the same window, and the title of window
# will be updated with `win_name`.
if not hasattr(self, win_name):
self._cv_win_name = win_name
cv2.namedWindow(winname=f'{id(self)}')
cv2.setWindowTitle(f'{id(self)}', win_name)
else:
cv2.setWindowTitle(f'{id(self)}', win_name)
shown_img = self.get_image() if drawn_img is None else drawn_img
cv2.imshow(str(id(self)), mmcv.bgr2rgb(shown_img))
cv2.waitKey(int(np.ceil(wait_time * 1000)))
else:
raise ValueError(f'got unsupported backend {self.backend}')