func crop(image *vips.Image, ow, oh int) error {
m := format.MetadataImage(image)
// If we have nothing to do, return.
if ow == m.Width && oh == m.Height {
return nil
}
// Center horizontally
x := (m.Width - ow + 1) / 2
// Assume faces are higher up vertically
y := (m.Height - oh + 1) / 4
if x < 0 || y < 0 {
panic("Bad crop offsets!")
}
return image.ExtractArea(m.Orientation.Crop(ow, oh, x, y, m.Width, m.Height))
}