VideoStream.py

# -*- coding: utf-8 -*-
"""
This example demonstrates the use of ImageView, which is a high-level widget for
displaying and analyzing 2D and 3D data. ImageView provides:

  1. A zoomable region (ViewBox) for displaying the image
  2. A combination histogram and gradient editor (HistogramLUTItem) for
     controlling the visual appearance of the image
  3. A timeline for selecting the currently displayed frame (for 3D data only).
  4. Tools for very basic analysis of image data (see ROI and Norm buttons)

"""
## Add path to library (just for examples; you do not need this)
import initExample

import numpy as np
from pyqtgraph.Qt import QtCore, QtGui
import pyqtgraph as pg
import pyqtgraph.ptime as ptime

import cv2 as cv

app = QtGui.QApplication([])

## Create window with ImageView widget
win = QtGui.QMainWindow()
win.resize(800,800)
# imv = pg.ImageView()
img = pg.ImageView()
# img.setPalette()
win.setCentralWidget(img)

pg.setConfigOption('background', 'w')

fpsLabel = QtGui.QLabel()
font = QtGui.QFont()
font.setPointSize(120)

fpsLabel.setFont(font)
fpsLabel.setAlignment(QtCore.Qt.AlignCenter)

win.show()

## Load a video
vid  = cv.VideoCapture('/Users/nickgravish/Dropbox/Harvard/HighThroughputExpt/2016-08-05_12.41.20/'
                       '1_08-05-16_12-41-31.770_Fri_Aug_05_12-41-20.543_115.mp4')
NUMFRAMES = vid.get(cv.CAP_PROP_FRAME_COUNT)


# frames = []
#
# for kk in range(int(NUMFRAMES)):
#     tru, ret = vid.read(1)
#     frames.append(ret[:,:,0])
#     print(kk)
#
# print(len(frames))
#
# ## convert to numpy array for setImage
# frames = np.asarray(frames)
# frames = frames.swapaxes(1,2)

## Display the data and assign each frame a time value from 1.0 to 3.0
lastTime = ptime.time()

def update():
    global data, lastTime, fpsLabel

    ret, data = vid.read(1)
    img.setImage(data[:,:,0].T, autoLevels=False)
    now = ptime.time()
    dt = now - lastTime
    lastTime = now
    fps = 1.0/dt
    fpsLabel.setText('%0.2f fps' % fps)
    app.processEvents()  ## force complete redraw for every plot

timer = QtCore.QTimer()
timer.timeout.connect(update)
timer.start(0)


## Start Qt event loop unless running in interactive mode.
if __name__ == '__main__':
    import sys
    if (sys.flags.interactive != 1) or not hasattr(QtCore, 'PYQT_VERSION'):
        QtGui.QApplication.instance().exec_()