Basic opencv with evision without async genserver

basic_ocv.ex

defmodule Eye do
  alias Evision, as: Cv

  def read(video, frame_read, count) when frame_read != false do
    scale = 0.5
    {height, width, _channels} = frame_read.shape
    new_width = trunc(width * scale)
    new_height = trunc(height * scale)

    frame_read
    |> Cv.resize({new_width, new_height})
    |> then(&Cv.HighGui.imshow("janela", &1))

    Cv.HighGui.waitKey(1)
    # Cv.HighGui.destroyWindow("janela")

    frame_read = Cv.VideoCapture.read(video)
    read(video, frame_read, count - 1)
  end

  def read(_, false, _) do
    Cv.HighGui.destroyAllWindows()
  end

  def run do
    rtsp_url = System.fetch_env!("RTSP_CAM")
    video = Cv.VideoCapture.videoCapture(rtsp_url)

    frame_read = Cv.VideoCapture.read(video)

    read(video, frame_read, video.frame_count)
  end
end