/* This file is part of GEGL.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 3 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
 *
 * 2013 Daniel Sabo
 */

#ifndef __GEGL_ALGORITHMS_H__
#define __GEGL_ALGORITHMS_H__

G_BEGIN_DECLS

#define GEGL_SCALE_EPSILON 1.e-6

void gegl_downscale_2x2 (const Babl *format,
                         gint    src_width,
                         gint    src_height,
                         guchar *src_data,
                         gint    src_rowstride,
                         guchar *dst_data,
                         gint    dst_rowstride);

void gegl_downscale_2x2_double (gint    bpp,
                                gint    src_width,
                                gint    src_height,
                                guchar *src_data,
                                gint    src_rowstride,
                                guchar *dst_data,
                                gint    dst_rowstride);

void gegl_downscale_2x2_float (gint    bpp,
                               gint    src_width,
                               gint    src_height,
                               guchar *src_data,
                               gint    src_rowstride,
                               guchar *dst_data,
                               gint    dst_rowstride);

void gegl_downscale_2x2_u32 (gint    bpp,
                             gint    src_width,
                             gint    src_height,
                             guchar *src_data,
                             gint    src_rowstride,
                             guchar *dst_data,
                             gint    dst_rowstride);

void gegl_downscale_2x2_u16 (gint    bpp,
                             gint    src_width,
                             gint    src_height,
                             guchar *src_data,
                             gint    src_rowstride,
                             guchar *dst_data,
                             gint    dst_rowstride);

void gegl_downscale_2x2_u8 (gint    bpp,
                            gint    src_width,
                            gint    src_height,
                            guchar *src_data,
                            gint    src_rowstride,
                            guchar *dst_data,
                            gint    dst_rowstride);

void gegl_downscale_2x2_nearest (gint    bpp,
                                 gint    src_width,
                                 gint    src_height,
                                 guchar *src_data,
                                 gint    src_rowstride,
                                 guchar *dst_data,
                                 gint    dst_rowstride);

/* Attempt to resample with a 3x3 boxfilter, if no boxfilter is
 * available for #format fall back to nearest neighbor.
 * #scale is assumed to be between 0.5 and +inf.
 */
void gegl_resample_boxfilter (guchar              *dest_buf,
                              const guchar        *source_buf,
                              const GeglRectangle *dst_rect,
                              const GeglRectangle *src_rect,
                              gint                 s_rowstride,
                              gdouble              scale,
                              const Babl          *format,
                              gint                 d_rowstride);

void gegl_resample_boxfilter_double (guchar              *dest_buf,
                                     const guchar        *source_buf,
                                     const GeglRectangle *dst_rect,
                                     const GeglRectangle *src_rect,
                                     gint                 s_rowstride,
                                     gdouble              scale,
                                     gint                 bpp,
                                     gint                 d_rowstride);

void gegl_resample_boxfilter_float (guchar              *dest_buf,
                                    const guchar        *source_buf,
                                    const GeglRectangle *dst_rect,
                                    const GeglRectangle *src_rect,
                                    gint                 s_rowstride,
                                    gdouble              scale,
                                    gint                 bpp,
                                    gint                 d_rowstride);

void gegl_resample_boxfilter_u32 (guchar              *dest_buf,
                                  const guchar        *source_buf,
                                  const GeglRectangle *dst_rect,
                                  const GeglRectangle *src_rect,
                                  gint                 s_rowstride,
                                  gdouble              scale,
                                  gint                 bpp,
                                  gint                 d_rowstride);

void gegl_resample_boxfilter_u16 (guchar              *dest_buf,
                                  const guchar        *source_buf,
                                  const GeglRectangle *dst_rect,
                                  const GeglRectangle *src_rect,
                                  gint                 s_rowstride,
                                  gdouble              scale,
                                  gint                 bpp,
                                  gint                 d_rowstride);

void gegl_resample_boxfilter_u8 (guchar              *dest_buf,
                                 const guchar        *source_buf,
                                 const GeglRectangle *dst_rect,
                                 const GeglRectangle *src_rect,
                                 gint                 s_rowstride,
                                 gdouble              scale,
                                 gint                 bpp,
                                 gint                 d_rowstride);

void gegl_resample_nearest (guchar              *dst,
                            const guchar        *src,
                            const GeglRectangle *dst_rect,
                            const GeglRectangle *src_rect,
                            gint                 src_stride,
                            gdouble              scale,
                            gint                 bpp,
                            gint                 dst_stride);

G_END_DECLS

#endif /* __GEGL_ALGORITHMS_H__ */