Computer Vision Core

This repo is organized as a python package that contains utilities for various computer vision problems.

We mostly use opencv / numpy / scipy functionality to implement higher level utilities that are easier to use. The explicit implementation and software architecture in this repo are also a good reference for dedicated implementation (e.g. unique embedded systems).

Setup

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install with pip

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This repo can be installed with pip as a python package.

1. clone / download this repo

2. setup your python env 3.11+ (virtual env recommended)

3. install this package into your python

   pip install upgrade pip pip install '/local/path/to/cv_core'

• install options:

  some of the functionality in the cv_core.geometry_2D and cv_core.geometry_3D subpackages had dual implementation:

  • explicit implementation using only numpy
  • shapely implementation

  Explicit implementation is good if you don't want to import shapely, and can also be used as a reference for embedded implementation. Shapely implementation is more reliable, and probably faster.

  If you want to use the shapely implementation:

  • install with shaply extra:

    pip install '/local/path/to/cv_core'[shapely]
    

  • set use_shaply=True when calling the relevant functions.

4. verify installation is OK:

   pip install show cv_core

manual Setup

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1. clone / download this repo

2. setup your python env 3.11+ (virtual env recommended)

3. install python packages according to requirements.txt

4. import cv_core to your python program by adding to python path

   import sys sys.path.append('/local/path/to/cv_core')

Usage

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import cv_core and use as a python package.

This repo contains useful functionality in various computer vision areas.

2D Geometry

The cv_core.2D_geometry module implements functionality that is related to basic 2D geometry.

major notations:

• 2D point is described by (x, y)
• 2D line is described by (a, b, c) where ax+by+c=0

Useful functionality:

• line parameters from two points
• point line parameterization
• intersect two lines
• intersect two line segments
• intersect line segment with polygon

3D Geometry

The cv_core.3D_geometry module implements functionality that is related to basic 3D geometry.

major notations:

• 3D plane is handled by Plane3D class
• rigid 3D transform is handled by Rigid3dTform class

Useful functionality:

• 3D plane functionality:
  • project points to plane (by normal direction or any axis)
  • ray-plane intersection
  • plot
• Rigid3dTform functionality:
  • invert
  • multiply
  • transform points

Pinhole Camera

The cv_core.pinhole_camera module implements functionality that is related to camera geometry.

major notations:

• camera is handled by PinholeCamera class

Useful functionality:

• Camera Calibration:
  • intrinsic calibration pinhole / fisheye
  • stereo calibration
  • visual - inertial calibration (based on Kalibr)
• PinholeCamera functionality:
  • project world point to pixel
  • back-project pixel to 3D world ray
  • plot
• lens selector utility