roi

function out = roi(filename,args)
  out = "";
  if typeinfo(args) == "string"
    in = imread(filename);
    mask = imread(args);
    result = in .* mask;
    imwrite(result,"result.png");
    out = "result.png";
    return
  else
    if length(args) != 2 || length(args(:,:)) != 2
      return
    endif
    in = imread(filename);
    pointA = args(1,:);
    pointB = args(2,:);
    if (pointA(1) < 0 || pointB(1) < 0 || pointA(2) < 0 || pointB(2) < 0
    || pointA(1) >= columns(in) || pointA(2) >= rows(in)
    || pointB(1) >= columns(in) || pointB(2) >= rows(in))
      return
    endif
    pointA = pointA + 1;
    pointB = pointB + 1;
    mask_temp = ones(pointB(2)-pointA(2)+1,pointB(1)-pointA(1)+1);
    mask = zeros(rows(in),columns(in));
    mask(pointA(2):pointB(2),pointA(1):pointB(1)) = mask_temp;
    result = in .* mask;
    imwrite(result,"result.png");
    out = "result.png";
  endif
endfunction