module ChunkyPNG::Canvas::Adam7Interlacing

def adam7_pass_size(pass, original_width, original_height)

Parameters:

original_height (Integer) -- The height of the original image.
original_width (Integer) -- The width of the original image.
pass (Integer) -- The pass number, should be in 0..6.

def adam7_pass_size(pass, original_width, original_height)
  x_shift, x_offset, y_shift, y_offset = adam7_multiplier_offset(pass)
  [
    (original_width  - x_offset + (1 << x_shift) - 1) >> x_shift,
    (original_height - y_offset + (1 << y_shift) - 1) >> y_shift,
  ]
end

Instance Methods