+int qscale_save_jpeg(const qscale_img *image, const char *filename, int jpeg_quality);
-qscale_img *qscale_scale(qscale_img *source, int width, int height, int samp_h0, int samp_v0, int samp_h1, int samp_v1, int samp_h2, int samp_v2, int jpeg_quality);
+qscale_img *qscale_scale(qscale_img *source, int width, int height, int samp_h0, int samp_v0, int samp_h1, int samp_v1, int samp_h2, int samp_v2, enum qscale_scaling_filter scaling_filter);