Module torpido.video.video_reader
Expand source code
import gc
from queue import Queue, Empty
from threading import Thread
import cv2
from torpido.config import Log
from torpido.config.constants import VIDEO_WIDTH
from torpido.util import resize
class VideoGet:
"""
Class that continuously gets frames from a VideoCapture object
with a dedicated thread, which actually speeds up the video
reading 2 times faster than working in the main UI Thread.
Attributes
----------
__Q : queue
python queue for storing the frames that are to be processed
stream : video capture
open cv stream object that read the video in frames
stopped : bool
stream is ended or the video is not ended yet
Examples
--------
Reads the video using the Thread and saving the frames in the queue
to process them. As the video is read by the Thread the speed increases
and locking functions of open cv can be skipped.
"""
def __init__(self, src):
cv2.setUseOptimized(True)
self.__Q = Queue(maxsize=1200)
self.stream = cv2.VideoCapture(src)
self.stopped = False
def start(self):
"""
Create the thread
"""
Thread(target=self.__get, args=()).start()
return self
def __get(self):
"""
Reads the frame from the stream, much faster
in the thread, if queue is full wait for it to
be process
"""
while True:
if self.stopped:
return
if not self.__Q.full():
(grabbed, frame) = self.stream.read()
if not grabbed:
self.stop()
return
frame = resize(frame, width=VIDEO_WIDTH)
self.__Q.put(frame)
def read(self):
"""
Get the frame from the queue
Returns
-------
frame : object
returns the frame to process, if timeout(queue lock) occurs None is returned
"""
try:
data = self.__Q.get(True, 3)
except Empty:
data = None
return data
def getCapture(self):
"""
Returns the video stream of open cv
Returns
-------
object
stream of the video
"""
return self.stream
def getQueueSize(self):
"""
Returns the size of the queue
Returns
-------
int
size of the queue
"""
return self.__Q.qsize()
def more(self):
"""
checking if the video is still processing or done
"""
return not self.stopped
def stop(self):
"""
Explicitly ending the reading of the video stream. Minor clean ups
"""
self.stopped = True
Log.d(f"Garbage collected :: {gc.collect()}")
self.stream.release()
def __del__(self):
del self.__QClasses
class VideoGet (src)-
Class that continuously gets frames from a VideoCapture object with a dedicated thread, which actually speeds up the video reading 2 times faster than working in the main UI Thread.
Attributes
__Q:queue- python queue for storing the frames that are to be processed
stream:video capture- open cv stream object that read the video in frames
stopped:bool- stream is ended or the video is not ended yet
Examples
Reads the video using the Thread and saving the frames in the queue to process them. As the video is read by the Thread the speed increases and locking functions of open cv can be skipped.
Expand source code
class VideoGet: """ Class that continuously gets frames from a VideoCapture object with a dedicated thread, which actually speeds up the video reading 2 times faster than working in the main UI Thread. Attributes ---------- __Q : queue python queue for storing the frames that are to be processed stream : video capture open cv stream object that read the video in frames stopped : bool stream is ended or the video is not ended yet Examples -------- Reads the video using the Thread and saving the frames in the queue to process them. As the video is read by the Thread the speed increases and locking functions of open cv can be skipped. """ def __init__(self, src): cv2.setUseOptimized(True) self.__Q = Queue(maxsize=1200) self.stream = cv2.VideoCapture(src) self.stopped = False def start(self): """ Create the thread """ Thread(target=self.__get, args=()).start() return self def __get(self): """ Reads the frame from the stream, much faster in the thread, if queue is full wait for it to be process """ while True: if self.stopped: return if not self.__Q.full(): (grabbed, frame) = self.stream.read() if not grabbed: self.stop() return frame = resize(frame, width=VIDEO_WIDTH) self.__Q.put(frame) def read(self): """ Get the frame from the queue Returns ------- frame : object returns the frame to process, if timeout(queue lock) occurs None is returned """ try: data = self.__Q.get(True, 3) except Empty: data = None return data def getCapture(self): """ Returns the video stream of open cv Returns ------- object stream of the video """ return self.stream def getQueueSize(self): """ Returns the size of the queue Returns ------- int size of the queue """ return self.__Q.qsize() def more(self): """ checking if the video is still processing or done """ return not self.stopped def stop(self): """ Explicitly ending the reading of the video stream. Minor clean ups """ self.stopped = True Log.d(f"Garbage collected :: {gc.collect()}") self.stream.release() def __del__(self): del self.__QMethods
def getCapture(self)-
Returns the video stream of open cv
Returns
object- stream of the video
Expand source code
def getCapture(self): """ Returns the video stream of open cv Returns ------- object stream of the video """ return self.stream def getQueueSize(self)-
Returns the size of the queue
Returns
int- size of the queue
Expand source code
def getQueueSize(self): """ Returns the size of the queue Returns ------- int size of the queue """ return self.__Q.qsize() def more(self)-
checking if the video is still processing or done
Expand source code
def more(self): """ checking if the video is still processing or done """ return not self.stopped def read(self)-
Get the frame from the queue
Returns
frame:object- returns the frame to process, if timeout(queue lock) occurs None is returned
Expand source code
def read(self): """ Get the frame from the queue Returns ------- frame : object returns the frame to process, if timeout(queue lock) occurs None is returned """ try: data = self.__Q.get(True, 3) except Empty: data = None return data def start(self)-
Create the thread
Expand source code
def start(self): """ Create the thread """ Thread(target=self.__get, args=()).start() return self def stop(self)-
Explicitly ending the reading of the video stream. Minor clean ups
Expand source code
def stop(self): """ Explicitly ending the reading of the video stream. Minor clean ups """ self.stopped = True Log.d(f"Garbage collected :: {gc.collect()}") self.stream.release()