Inheritance diagram for application_util.image_viewer.ImageViewer:

Public Member Functions
def	__init__
def	annotate
def	circle
def	color
def	color
def	colored_points
def	disable_videowriter
def	enable_videowriter
def	gaussian
def	rectangle
def	run
def	stop
Public Attributes
	image
	text_color
	thickness
Private Attributes
	_caption
	_color
	_terminate
	_update_ms
	_user_fun
	_video_writer
	_window_shape

Detailed Description

An image viewer with drawing routines and video capture capabilities.

Key Bindings:

* 'SPACE' : pause
* 'ESC' : quit

Parameters
----------
update_ms : int
    Number of milliseconds between frames (1000 / frames per second).
window_shape : (int, int)
    Shape of the window (width, height).
caption : Optional[str]
    Title of the window.

Attributes
----------
image : ndarray
    Color image of shape (height, width, 3). You may directly manipulate
    this image to change the view. Otherwise, you may call any of the
    drawing routines of this class. Internally, the image is treated as
    beeing in BGR color space.

    Note that the image is resized to the the image viewers window_shape
    just prior to visualization. Therefore, you may pass differently sized
    images and call drawing routines with the appropriate, original point
    coordinates.
color : (int, int, int)
    Current BGR color code that applies to all drawing routines.
    Values are in range [0-255].
text_color : (int, int, int)
    Current BGR text color code that applies to all text rendering
    routines. Values are in range [0-255].
thickness : int
    Stroke width in pixels that applies to all drawing routines.

Definition at line 61 of file image_viewer.py.

Constructor & Destructor Documentation

def application_util.image_viewer.ImageViewer.__init__	(	self,
		update_ms,
		window_shape = `(640, 480`,
		caption = `"Figure 1"`
	)

Definition at line 101 of file image_viewer.py.

Member Function Documentation

def application_util.image_viewer.ImageViewer.annotate	(	self,
		x,
		y,
		text
	)

Draws a text string at a given location.

Parameters
----------
x : int | float
    Bottom-left corner of the text in the image (x-axis).
y : int | float
    Bottom-left corner of the text in the image (y-axis).
text : str
    The text to be drawn.

Definition at line 213 of file image_viewer.py.

def application_util.image_viewer.ImageViewer.circle	(	self,
		x,
		y,
		radius,
		label = `None`
	)

Draw a circle.

Parameters
----------
x : float | int
    Center of the circle (x-axis).
y : float | int
    Center of the circle (y-axis).
radius : float | int
    Radius of the circle in pixels.
label : Optional[str]
    A text label that is placed at the center of the circle.

Definition at line 156 of file image_viewer.py.

def application_util.image_viewer.ImageViewer.color ( self )

Definition at line 115 of file image_viewer.py.

def application_util.image_viewer.ImageViewer.color	(	self,
		value
	)

Definition at line 119 of file image_viewer.py.

def application_util.image_viewer.ImageViewer.colored_points	(	self,
		points,
		colors = `None`,
		skip_index_check = `False`
	)

Draw a collection of points.

The point size is fixed to 1.

Parameters
----------
points : ndarray
    The Nx2 array of image locations, where the first dimension is
    the x-coordinate and the second dimension is the y-coordinate.
colors : Optional[ndarray]
    The Nx3 array of colors (dtype=np.uint8). If None, the current
    color attribute is used.
skip_index_check : Optional[bool]
    If True, index range checks are skipped. This is faster, but
    requires all points to lie within the image dimensions.

Definition at line 229 of file image_viewer.py.

def application_util.image_viewer.ImageViewer.disable_videowriter ( self )

Disable writing videos.

Definition at line 280 of file image_viewer.py.

def application_util.image_viewer.ImageViewer.enable_videowriter	(	self,
		output_filename,
		fourcc_string = `"MJPG"`,
		fps = `None`
	)

Write images to video file.

Parameters
----------
output_filename : str
    Output filename.
fourcc_string : str
    The OpenCV FOURCC code that defines the video codec (check OpenCV
    documentation for more information).
fps : Optional[float]
    Frames per second. If None, configured according to current
    parameters.

Definition at line 258 of file image_viewer.py.

def application_util.image_viewer.ImageViewer.gaussian	(	self,
		mean,
		covariance,
		label = `None`
	)

Draw 95% confidence ellipse of a 2-D Gaussian distribution.

Parameters
----------
mean : array_like
    The mean vector of the Gaussian distribution (ndim=1).
covariance : array_like
    The 2x2 covariance matrix of the Gaussian distribution.
label : Optional[str]
    A text label that is placed at the center of the ellipse.

Definition at line 186 of file image_viewer.py.

def application_util.image_viewer.ImageViewer.rectangle	(	self,
		x,
		y,
		w,
		h,
		label = `None`
	)

Draw a rectangle.

Parameters
----------
x : float | int
    Top left corner of the rectangle (x-axis).
y : float | int
    Top let corner of the rectangle (y-axis).
w : float | int
    Width of the rectangle.
h : float | int
    Height of the rectangle.
label : Optional[str]
    A text label that is placed at the top left corner of the
    rectangle.

Definition at line 124 of file image_viewer.py.

def application_util.image_viewer.ImageViewer.run	(	self,
		update_fun = `None`
	)

Start the image viewer.

This method blocks until the user requests to close the window.

Parameters
----------
update_fun : Optional[Callable[] -> None]
    An optional callable that is invoked at each frame. May be used
    to play an animation/a video sequence.

Definition at line 285 of file image_viewer.py.

def application_util.image_viewer.ImageViewer.stop ( self )

Stop the control loop.

After calling this method, the viewer will stop execution before the
next frame and hand over control flow to the user.

Parameters
----------

Definition at line 335 of file image_viewer.py.