pyvision3

A computer vision library that complements OpenCV 3.x to add many useful features for developers and scientists alike. Pyvision3 is intended to be a successor to Pyvision that takes advantage of OpenCV 3.x and Python 3.x features. Huge thanks to David Bolme for being the originator of Pyvision. Many of the ease-of-use and interface ideas from the original Pyvision are carried forward, albeit with new implementations for Pyvision3.

Installation

Install prerequisites:

• python 3.4
• numpy
• opencv 3.x with bindings for python 3.4
• matplotlib (optional, recommended)
• shapely (optional, annotating polygons)

In the root directory of the pyvision code (the directory containing the setup.py script), run the following to install to the system packages:

python setup.py install

Or the following to install only for the current user:

python setup.py install --user

Examples

import pyvision as pv3

#load and display an image
img = pv3.Image("path/to/somefile.jpg")
img.show()

#annotate the image
img.annotate_text("Waldo was here", (254, 246), color=(0, 0, 255), bg_color=(255, 255, 255))
img.show()  # by default uses an opencv highgui window for display
img.imshow()  # will use a matplotlib figure, optional arguments are the same as img.show()

#annotations are on a separate layer, original data is still there
img.show(annotations=False)

#load and play a video or webcam
vid = pv3.Video("path/to/somevideo.mov")
vid.play()  #supports pausing and single-frame advance

#We can control the position of playback in the video
vid.play(start_frame=150, end_frame=400)

#or you can treat a video as an iterator
for img in vid:
	print(vid.current_frame_number)
	img.show(delay=25) #25ms delay between frames


#motion detection
md = pv3.MotionDetector(method=pv3.BG_SUBTRACT_FRAME_DIFF, buff_size=5, thresh=80)
for img in vid:
    md.detect(img)
    out = md.annotate_frame()
    if out is not None:
        out.show(delay=25)

Main Contributors to Pyvision3

Stephen O'Hara

Main Contributors to the original Pyvision

1. David Bolme
2. Stephen O'Hara

Backwards Compatibility

Pyvision3 is not (necessarily) designed to be backwards compatible to earlier versions of Python and OpenCV. For those developing with Python 2.7, I suggest continuing to use the original Pyvision code, which can be found on github.