video

Classes for displaying streamed video

Classes:

Video(videos[, fps])	Display Video data as it is collected.
ImageItem_TimedUpdate(*args, **kwargs)	Reclass of pyqtgraph.ImageItem to update with a fixed fps.

class Video(videos, fps=None)

Bases: QWidget

Display Video data as it is collected.

Uses the ImageItem_TimedUpdate class to do timed frame updates.

Parameters:

• videos (list, tuple) – Names of video streams that will be displayed

• fps (int) – if None, draw according to prefs.get('DRAWFPS'). Otherwise frequency of widget update

Variables:

• videos (list, tuple) – Names of video streams that will be displayed

• fps (int) – if None, draw according to prefs.get('DRAWFPS'). Otherwise frequency of widget update

• ifps (int) – 1/fps, duration of frame in s

• qs (dict) – Dictionary of :class:`~queue.Queue`s in which frames will be dumped

• quitting (threading.Event) – Signal to quit drawing

• update_thread (threading.Thread) – Thread with target=:meth:~.Video._update_frame

• layout (PySide6.QtWidgets.QGridLayout) – Widget layout

• vid_widgets (dict) – dict containing widgets for each of the individual video streams.

Methods:

init_gui()
update_frame(video, data)	Put a frame for a video stream into its queue.
release()

Attributes:

staticMetaObject

init_gui()

update_frame(video, data)

Put a frame for a video stream into its queue.

If there is a waiting frame, pull it from the queue first – it’s old now.

Parameters:

• video (str) – name of video stream

• data (numpy.ndarray) – video frame

release()

staticMetaObject = PySide6.QtCore.QMetaObject("Video" inherits "QWidget": )

class ImageItem_TimedUpdate(*args, **kwargs)

Bases: ImageItem

Reclass of pyqtgraph.ImageItem to update with a fixed fps.

Rather than calling update() every time a frame is updated, call it according to the timer.

fps is set according to prefs.get('DRAWFPS'), if not available, draw at 10fps

Variables:

timer (QTimer) – Timer held in globals() that synchronizes frame updates across image items

See setOpts() for further keyword arguments and and setImage() for information on supported formats.

Parameters

image: np.ndarray, optional

Image data

Methods:

setImage([image, autoLevels])	Updates the image displayed by this ImageItem.
update_img()	Call update()

Attributes:

staticMetaObject

setImage(image=None, autoLevels=None, **kargs)

Updates the image displayed by this ImageItem. For more information on how the image is processed before displaying, see makeARGB().

For backward compatibility, image data is assumed to be in column-major order (column, row) by default. However, most data is stored in row-major order (row, column). It can either be transposed before assignment:

imageitem.setImage(imagedata.T)

or the interpretation of the data can be changed locally through the axisOrder keyword or by changing the imageAxisOrder global configuration option

All keywords supported by setOpts() are also allowed here.

Parameters

image: np.ndarray, optional

Image data given as NumPy array with an integer or floating point dtype of any bit depth. A 2-dimensional array describes single-valued (monochromatic) data. A 3-dimensional array is used to give individual color components. The third dimension must be of length 3 (RGB) or 4 (RGBA).

rect: QRectF or QRect or array_like, optional

If given, sets translation and scaling to display the image within the specified rectangle. If array_like should be the form of floats [x, y, w, h] See setRect()

autoLevels: bool, optional

If True, ImageItem will automatically select levels based on the maximum and minimum values encountered in the data. For performance reasons, this search subsamples the images and may miss individual bright or or dark points in the data set.

If False, the search will be omitted.

The default is False if a levels keyword argument is given, and True otherwise.

levelSamples: int, default 65536

When determining minimum and maximum values, ImageItem only inspects a subset of pixels no larger than this number. Setting this larger than the total number of pixels considers all values.

staticMetaObject = PySide6.QtCore.QMetaObject("ImageItem_TimedUpdate" inherits "ImageItem": )

update_img()

Call update()