+ /*
+ * http://www.koders.com/c/fid80DBBF1D49D004EF71CE7C493C34610C4F17D3D3.aspx
+ * http://studio.imagemagick.org/pipermail/magick-users/2002-September/004685.html
+ * You need to set -quality 101 or greater. If quality is 100 or less you
+ * get regular JPEG output. This is not explained in the documentation, only
+ * in the comments in coder/jpeg.c. When you have configured libjpeg with
+ * lossless support, then
+ *
+ * quality=predictor*100 + point_transform
+ *
+ * If you don't know what these values should be, just use 101.
+ * They only affect the compression ratio, not the image appearance,
+ * which is lossless.
+ */
+ jpeg_simple_lossless (&cinfo, 1, 0);