/* GStreamer

 * Copyright (C) <2014> Wim Taymans <wim.taymans@gmail.com>

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Library General Public

 * License as published by the Free Software Foundation; either

 * version 2 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

 * Library General Public License for more details.

 *

 * You should have received a copy of the GNU Library General Public

 * License along with this library; if not, write to the

 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,

 * Boston, MA 02110-1301, USA.

 */

#ifndef __GST_VIDEO_RESAMPLER_H__

#define __GST_VIDEO_RESAMPLER_H__

#include <gst/gst.h>

#include <gst/video/video-prelude.h>

G_BEGIN_DECLS

typedef struct _GstVideoResampler GstVideoResampler;

/**

 * GstVideoResamplerMethod:

 * @GST_VIDEO_RESAMPLER_METHOD_NEAREST: Duplicates the samples when

 *    upsampling and drops when downsampling

 * @GST_VIDEO_RESAMPLER_METHOD_LINEAR: Uses linear interpolation to reconstruct

 *    missing samples and averaging to downsample

 * @GST_VIDEO_RESAMPLER_METHOD_CUBIC: Uses cubic interpolation

 * @GST_VIDEO_RESAMPLER_METHOD_SINC: Uses sinc interpolation

 * @GST_VIDEO_RESAMPLER_METHOD_LANCZOS: Uses lanczos interpolation

 *

 * Different subsampling and upsampling methods

 *

 * Since: 1.6

 */

typedef enum {

  GST_VIDEO_RESAMPLER_METHOD_NEAREST,

  GST_VIDEO_RESAMPLER_METHOD_LINEAR,

  GST_VIDEO_RESAMPLER_METHOD_CUBIC,

  GST_VIDEO_RESAMPLER_METHOD_SINC,

  GST_VIDEO_RESAMPLER_METHOD_LANCZOS

} GstVideoResamplerMethod;

/**

 * GST_VIDEO_RESAMPLER_OPT_CUBIC_B:

 *

 * G_TYPE_DOUBLE, B parameter of the cubic filter. The B

 * parameter controls the bluriness. Values between 0.0 and

 * 2.0 are accepted. 1/3 is the default.

 *

 * Below are some values of popular filters:

 *                    B       C

 * Hermite           0.0     0.0

 * Spline            1.0     0.0

 * Catmull-Rom       0.0     1/2

 * Mitchell          1/3     1/3

 * Robidoux          0.3782  0.3109

 * Robidoux

 *  Sharp            0.2620  0.3690

 * Robidoux

 *  Soft             0.6796  0.1602

 */

#define GST_VIDEO_RESAMPLER_OPT_CUBIC_B      "GstVideoResampler.cubic-b"

/**

 * GST_VIDEO_RESAMPLER_OPT_CUBIC_C:

 *

 * G_TYPE_DOUBLE, C parameter of the cubic filter. The C

 * parameter controls the Keys alpha value. Values between 0.0 and

 * 2.0 are accepted. 1/3 is the default.

 *

 * See #GST_VIDEO_RESAMPLER_OPT_CUBIC_B for some more common values

 */

#define GST_VIDEO_RESAMPLER_OPT_CUBIC_C      "GstVideoResampler.cubic-c"

/**

 * GST_VIDEO_RESAMPLER_OPT_ENVELOPE:

 *

 * G_TYPE_DOUBLE, specifies the size of filter envelope for

 * @GST_VIDEO_RESAMPLER_METHOD_LANCZOS. values are clamped between

 * 1.0 and 5.0. 2.0 is the default.

 */

#define GST_VIDEO_RESAMPLER_OPT_ENVELOPE      "GstVideoResampler.envelope"

/**

 * GST_VIDEO_RESAMPLER_OPT_SHARPNESS:

 *

 * G_TYPE_DOUBLE, specifies sharpness of the filter for

 * @GST_VIDEO_RESAMPLER_METHOD_LANCZOS. values are clamped between

 * 0.5 and 1.5. 1.0 is the default.

 */

#define GST_VIDEO_RESAMPLER_OPT_SHARPNESS     "GstVideoResampler.sharpness"

/**

 * GST_VIDEO_RESAMPLER_OPT_SHARPEN:

 *

 * G_TYPE_DOUBLE, specifies sharpening of the filter for

 * @GST_VIDEO_RESAMPLER_METHOD_LANCZOS. values are clamped between

 * 0.0 and 1.0. 0.0 is the default.

 */

#define GST_VIDEO_RESAMPLER_OPT_SHARPEN      "GstVideoResampler.sharpen"

/**

 * GST_VIDEO_RESAMPLER_OPT_MAX_TAPS:

 *

 * G_TYPE_INT, limits the maximum number of taps to use.

 * 16 is the default.

 */

#define GST_VIDEO_RESAMPLER_OPT_MAX_TAPS     "GstVideoResampler.max-taps"

/**

 * GstVideoResamplerFlags:

 * @GST_VIDEO_RESAMPLER_FLAG_NONE: no flags

 * @GST_VIDEO_RESAMPLER_FLAG_HALF_TAPS: when no taps are given, half the

 *              number of calculated taps. This can be used when making scalers

 *              for the different fields of an interlaced picture. Since 1.10

 *

 * Different resampler flags.

 *

 * Since: 1.6

 */

typedef enum {

  GST_VIDEO_RESAMPLER_FLAG_NONE                 = (0),

  GST_VIDEO_RESAMPLER_FLAG_HALF_TAPS            = (1 << 0),

} GstVideoResamplerFlags;

/**

 * GstVideoResampler:

 * @in_size: the input size

 * @out_size: the output size

 * @max_taps: the maximum number of taps

 * @n_phases: the number of phases

 * @offset: array with the source offset for each output element

 * @phase: array with the phase to use for each output element

 * @n_taps: array with new number of taps for each phase

 * @taps: the taps for all phases

 *

 * A structure holding resampler information.

 *

 * Since: 1.6

 */

struct _GstVideoResampler

{

  gint in_size;

  gint out_size;

  guint max_taps;

  guint n_phases;

  guint32 *offset;

  guint32 *phase;

  guint32 *n_taps;

  gdouble *taps;

  /*< private >*/

  gpointer _gst_reserved[GST_PADDING];

};

GST_VIDEO_API

gboolean    gst_video_resampler_init      (GstVideoResampler *resampler,

                                           GstVideoResamplerMethod method,

                                           GstVideoResamplerFlags flags,

                                           guint n_phases, guint n_taps,

                                           gdouble shift,

                                           guint in_size, guint out_size,

                                           GstStructure *options);

GST_VIDEO_API

void        gst_video_resampler_clear     (GstVideoResampler *resampler);

G_END_DECLS

#endif /* __GST_VIDEO_RESAMPLER_H__ */