func jpegSave(image *vips.Image, options SaveOptions) ([]byte, error) {
// JPEG interlace saves 2-3%, but incurs a few hundred bytes of
// overhead, requires buffering the image completely in RAM for
// encoding and decoding, and takes over 3x the CPU. This isn't
// usually beneficial on small images and is too expensive for large
// images.
pixels := image.Xsize() * image.Ysize()
interlace := pixels >= 200*200 && pixels <= 1024*1024
// Strip and optimize both save space, enable them.
return image.JpegsaveBuffer(true, options.Quality, true, interlace)
}