ruby-opencv Invalid sequence error bug

bug.rb

require "opencv"

image = OpenCV::CvMat.new(100, 100, OpenCV::CV_8U, 1).fill(0)
image[50,50] = OpenCV::CvColor::White

def foo(image)
  image.find_contours
end

100_000.times do |i|
  object = []
  foo(image).first
end

# also encounters the same error, but takes longer

def foo(image)
  image.find_contours
end

2_000_000.times {|i| foo(image).first}

# also encounters the same error

1_000_000.times do |i|
  contours = image.find_contours

  current = contours
  current = current.h_next while current

  contours.first
end

Gemfile

source "https://rubygems.org"

gem "ruby-opencv"

Gemfile.lock

GEM
  remote: https://rubygems.org/
  specs:
    ruby-opencv (0.0.14)

PLATFORMS
  ruby

DEPENDENCIES
  ruby-opencv

BUNDLED WITH
   1.10.5

output.txt

bug.rb:12:in `first': Invalid sequence error. (TypeError)
	from bug.rb:12:in `block in <main>'
	from bug.rb:10:in `times'
	from bug.rb:10:in `<main>'