OpenCv

OpenCv NIF Bindings for Erlang/Elixir.

Current status

Currently almost nothing works. Opening a video device and capturing jpeg frames works currently.

Usage

Capturing a jpeg encoded frame frame can be done by:

Interactive Elixir (1.7.3) - press Ctrl+C to exit (type h() ENTER for help)
iex(1)> {:ok, conn} = OpenCv.new()
{:ok, #Reference<0.1511271170.1095630852.139975>}
iex(2)> {:ok, cap} = OpenCv.VideoCapture.open(conn, '/dev/video0')
{:ok, #Reference<0.1511271170.1095630848.138924>}
iex(3)> true = OpenCv.VideoCapture.is_opened(conn, cap)
true
iex(4)> {:ok, frame} = OpenCv.VideoCapture.read(conn, cap)
{:ok, #Reference<0.1511271170.1095630848.138925>}
iex(5)> jpg = OpenCv.imencode(conn, frame, '.jpg', [])
<<255, 216, 255, 224, 0, 16, 74, 70, 73, 70, 0, 1, 1, 0, 0, 1, 0, 1, 0, 0, 255,
  219, 0, 67, 0, 2, 1, 1, 1, 1, 1, 2, 1, 1, 1, 2, 2, 2, 2, 2, 4, 3, 2, 2, 2, 2,
  5, 4, 4, 3, ...>>
iex(6)> File.write("img.jpg", jpg)
:ok

Building

This currently supports opencv3 and opencv4. It may support opencv2, but I have not tested. Nerves builds are currently supported given you have a system that has opencv installed. this system has opencv 3 installed. I've only tested build on linux, and it is likely that paths for the Makefile may be wrong.

Installation

To pull in this package directly from GitHub, amend your list of dependencies in mix.exs as follows:

def deps do
  [
    {:open_cv, github: "ConnorRigby/elixir-opencv", branch: "master"}
  ]
end

If available in Hex, the package can be installed by adding open_cv to your list of dependencies in mix.exs:

def deps do
  [
    {:open_cv, "~> 0.1.0"}
  ]
end

Documentation can be generated with ExDoc and published on HexDocs. Once published, the docs can be found at https://hexdocs.pm/open_cv.