static BWImage markIntRangesOnTopOfBWImage(BWImage img, L<IntRange> l) {
  ret markIntRangesOnTopOfBWImage(img, l, 10);
}

static BWImage markIntRangesOnTopOfBWImage(BWImage img, L<IntRange> l, int h) {  BWImage bw = new(img.getWidth(), h+img.getHeight());
  copyBWImage(img, 0, 0, bw, 0, h);
  for (IntRange r : unnull(l))
    bwFillRect(bw, r.start, 0, r.end-r.start, h, 1f);
  ret bw;
}

static BWImage markIntRangesOnTopOfBWImage(BWImage img, L<IntRange> ranges1, L<IntRange> ranges2) {
  ret markIntRangesOnTopOfBWImage(
    markIntRangesOnTopOfBWImage(img, ranges2, 5),
    ranges1, 5);
}

Began life as a copy of #1018622