pystreaming.stream package

Submodules

pystreaming.stream.handlers module

pystreaming.stream.handlers.buffer(bufferlen, handlers)[source]

Buffer and reorder incoming packets of data.

Parameters

  • bufferlen ([type]) – Length of buffer, in seconds.

  • handlers (dict) – Dictionary of str: generator. The key is a stream name, the value is an unprimed generator.

Yields

tuple(str, data) – str is stream name, data is data packet from corresponding handler.

pystreaming.stream.handlers.dispfps(handler, n=100, write=False)[source]

Average iterations per second over last n iterations.

Parameters

  • handler (generator) – Generator that yields data.

  • n (int, optional) – Number of iterations to average over. Defaults to 100.

  • write (bool, optional) – Set to true to write FPS to data[‘arr’] instead of console, assuming it is a video frame. Defaults to False.

Yields

pyobj – Forwards data from handler

pystreaming.stream.handlers.display(frame, BGR=True)[source]

Display a frame using OpenCV.

Press [ESC] to stop.

Parameters

  • frame (np.ndarray) – Frame must have dtype uint8.

  • BGR (bool, optional) – Is frame in BGR format (This is OpenCV format). Defaults to True.

Raises

KeyboardInterrupt – Raised when [ESC] is pressed. Catch this exception to gracefully exit the stream.

pystreaming.stream.interface module

pystreaming.stream.interface.recv(*, socket, arr=False, buf=False, flags=0)[source]

Internal video data receive command.

Parameters

  • socket (zmq.Context.socket) – Socket through which to receive data.

  • arr (bool, optional) – Change to True if you expect an arr. Defaults to False.

  • buf (bool, optional) – Change to True if you expect a byte buffer. Defaults to False.

  • flags (int, optional) – Zmq flags to execute with (zmq.NOBLOCK). Defaults to 0.

Returns

Expected items, with possible keys: {arr, buf, meta, ftime, fno}.

Return type

dict

pystreaming.stream.interface.send(*, socket, fno, ftime, meta, arr=None, buf=None, flags=0)[source]

Internal video data send command.

Parameters

  • socket (zmq.Context.socket) – Socket through which to send data.

  • fno (int) – Frame number.

  • ftime (float) – Frame timestamp.

  • meta (pyobj) – Any reasonably small picklable object.

  • arr ([type], optional) – Numpy array to send. Defaults to None.

  • buf (bytes, optional) – Byte buffer to send. Defaults to None.

  • flags (int, optional) – Zmq flags to execute with (zmq.NOBLOCK or zmq.SNDMORE). Defaults to 0.

pystreaming.stream.patterns module

class pystreaming.stream.patterns.Receiver(endpoint, nproc=2, mapreduce=False)[source]

Bases: object

Receiver frames from a video stream.

Parameters

  • endpoint (str) – Descriptor of collection endpoint.

  • nproc (int, optional) – Number of processes devoted to decoding. Defaults to 2.

  • mapreduce (bool, optional) – Enable Map-Reduce streaming pattern. Defaults to False.

property handler

Returns a handler that is used for future data handling.

Returns

Generator that yields dicts with keys {arr, meta, ftime, fno}.

Return type

generator

start()[source]

Start internal pystreaming objects.

stop()[source]

Cleanup and stop interal pystreaming objects.

class pystreaming.stream.patterns.Streamer(endpoint, tracks=None, nproc=2, mapreduce=False)[source]

Bases: object

Video streamer with P2P and Map-Reduce functionality.

Parameters

  • endpoint (str) – Descriptor of video stream endpoint.

  • tracks (list[str], optional) – Video stream tracks. Defaults to None which is [“none”].

  • nproc (int, optional) – Number of processes devoted to encoding. Defaults to 2.

  • mapreduce (bool, optional) – Enable Map-Reduce streaming pattern. Defaults to False.

send(frame)[source]

Send a video frame into the stream.

Parameters

frame (np.ndarray) – Video frame

start()[source]

Start internal pystreaming devices.

stop()[source]

Cleanup and stop interal pystreaming objects.

testcard(card, animated=False)[source]

Display a testcard or a test image. Automatically starts the device if not already started. This method is blocking.

Parameters

  • card (int) – One of pystreaming.TEST_S pystreaming.TEST_M pystreaming.TEST_L pystreaming.IMAG_S pystreaming.IMAG_M pystreaming.IMAG_L

  • animated (bool, optional) – Set True to make image rotate. Defaults to False.

class pystreaming.stream.patterns.Worker(source, drain, track='none', reqthread=3, decproc=2)[source]

Bases: object

Worker in the Map-Reduce streaming pattern.

Parameters

  • source (str) – Descriptor of Streamer.

  • drain (str) – Descriptor of Receiver.

  • track (str, optional) – Video stream track name. Defaults to “none”.

  • reqthread (int, optional) – Number of request threads. Defaults to 3.

  • decproc (int, optional) – Number of decoder processes. Defaults to 2.

property handler

Returns a handler that is used for worker data handling.

Returns

Generator that yields dicts with keys {arr, buf, meta, ftime, fno}.

Return type

generator

send(data)[source]
start()[source]

Start internal pystreaming devices.

stop()[source]

Cleanup and stop interal pystreaming objects.

Module contents