/* GStreamer
 * Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>
 * Copyright (C) <2003> David Schleef <ds@schleef.org>
 * Copyright (C) 2003 Arwed v. Merkatz <v.merkatz@gmx.net>
 * Copyright (C) 2006 Mark Nauwelaerts <manauw@skynet.be>
 *
 * 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., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */

/*
 * This file was (probably) generated from
 * gstvideotemplate.c,v 1.12 2004/01/07 21:07:12 ds Exp 
 * and
 * make_filter,v 1.6 2004/01/07 21:33:01 ds Exp 
 */

/**
 * SECTION:element-gamma
 *
 * Performs gamma correction on a video stream.
 *
 * <refsect2>
 * <title>Example launch line</title>
 * |[
 * gst-launch videotestsrc ! gamma gamma=2.0 ! ffmpegcolorspace ! ximagesink
 * ]| This pipeline will make the image "brighter".
 * </refsect2>
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "gstgamma.h"
#ifdef HAVE_LIBOIL
#include <liboil/liboil.h>
#endif
#include <string.h>
#include <math.h>

#include <gst/video/video.h>


GST_DEBUG_CATEGORY_STATIC (gamma_debug);
#define GST_CAT_DEFAULT gamma_debug

/* GstGamma signals and args */
enum
{
  /* FILL ME */
  LAST_SIGNAL
};

enum
{
  PROP_0,
  PROP_GAMMA
      /* FILL ME */
};

#define DEFAULT_PROP_GAMMA  1

static const GstElementDetails gamma_details =
GST_ELEMENT_DETAILS ("Video gamma correction",
    "Filter/Effect/Video",
    "Adjusts gamma on a video stream",
    "Arwed v. Merkatz <v.merkatz@gmx.net");

static GstStaticPadTemplate gst_gamma_src_template =
GST_STATIC_PAD_TEMPLATE ("src",
    GST_PAD_SRC,
    GST_PAD_ALWAYS,
    GST_STATIC_CAPS (GST_VIDEO_CAPS_YUV ("{ IYUV, I420, YV12 }"))
    );

static GstStaticPadTemplate gst_gamma_sink_template =
GST_STATIC_PAD_TEMPLATE ("sink",
    GST_PAD_SINK,
    GST_PAD_ALWAYS,
    GST_STATIC_CAPS (GST_VIDEO_CAPS_YUV ("{ IYUV, I420, YV12 }"))
    );

static void gst_gamma_set_property (GObject * object, guint prop_id,
    const GValue * value, GParamSpec * pspec);
static void gst_gamma_get_property (GObject * object, guint prop_id,
    GValue * value, GParamSpec * pspec);

static gboolean gst_gamma_set_caps (GstBaseTransform * base, GstCaps * incaps,
    GstCaps * outcaps);
static GstFlowReturn gst_gamma_transform_ip (GstBaseTransform * transform,
    GstBuffer * buf);

static void gst_gamma_planar411_ip (GstGamma * gamma, guint8 * data, gint size);
static void gst_gamma_calculate_tables (GstGamma * gamma);

GST_BOILERPLATE (GstGamma, gst_gamma, GstVideoFilter, GST_TYPE_VIDEO_FILTER);


static void
gst_gamma_base_init (gpointer g_class)
{
  GstElementClass *element_class = GST_ELEMENT_CLASS (g_class);

  gst_element_class_set_details (element_class, &gamma_details);

  gst_element_class_add_pad_template (element_class,
      gst_static_pad_template_get (&gst_gamma_sink_template));
  gst_element_class_add_pad_template (element_class,
      gst_static_pad_template_get (&gst_gamma_src_template));
}

static void
gst_gamma_class_init (GstGammaClass * g_class)
{
  GObjectClass *gobject_class;
  GstBaseTransformClass *trans_class;

  gobject_class = G_OBJECT_CLASS (g_class);
  trans_class = GST_BASE_TRANSFORM_CLASS (g_class);

  gobject_class->set_property = gst_gamma_set_property;
  gobject_class->get_property = gst_gamma_get_property;

  g_object_class_install_property (gobject_class, PROP_GAMMA,
      g_param_spec_double ("gamma", "Gamma", "gamma",
          0.01, 10, DEFAULT_PROP_GAMMA, G_PARAM_READWRITE));

  trans_class->set_caps = GST_DEBUG_FUNCPTR (gst_gamma_set_caps);
  trans_class->transform_ip = GST_DEBUG_FUNCPTR (gst_gamma_transform_ip);
}

static void
gst_gamma_init (GstGamma * gamma, GstGammaClass * g_class)
{
  GST_DEBUG_OBJECT (gamma, "gst_gamma_init");

  /* properties */
  gamma->gamma = DEFAULT_PROP_GAMMA;
  gst_gamma_calculate_tables (gamma);
}

static void
gst_gamma_set_property (GObject * object, guint prop_id, const GValue * value,
    GParamSpec * pspec)
{
  GstGamma *gamma;

  g_return_if_fail (GST_IS_GAMMA (object));
  gamma = GST_GAMMA (object);

  GST_DEBUG ("gst_gamma_set_property");
  switch (prop_id) {
    case PROP_GAMMA:
      gamma->gamma = g_value_get_double (value);
      gst_gamma_calculate_tables (gamma);
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
  }
}

static void
gst_gamma_get_property (GObject * object, guint prop_id, GValue * value,
    GParamSpec * pspec)
{
  GstGamma *gamma;

  g_return_if_fail (GST_IS_GAMMA (object));
  gamma = GST_GAMMA (object);

  switch (prop_id) {
    case PROP_GAMMA:
      g_value_set_double (value, gamma->gamma);
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
  }
}

static void
gst_gamma_calculate_tables (GstGamma * gamma)
{
  int n;
  double val;
  double exp;

  if (gamma->gamma == 1.0) {
    GST_BASE_TRANSFORM (gamma)->passthrough = TRUE;
    return;
  }
  GST_BASE_TRANSFORM (gamma)->passthrough = FALSE;

  exp = 1.0 / gamma->gamma;
  for (n = 0; n < 256; n++) {
    val = n / 255.0;
    val = pow (val, exp);
    val = 255.0 * val;
    gamma->gamma_table[n] = (unsigned char) floor (val + 0.5);
  }
}

#ifndef HAVE_LIBOIL
void
oil_tablelookup_u8 (guint8 * dest, int dstr, guint8 * src, int sstr,
    guint8 * table, int tstr, int n)
{
  int i;

  for (i = 0; i < n; i++) {
    *dest = table[*src * tstr];
    dest += dstr;
    src += sstr;
  }
}
#endif

/* Useful macros */
#define GST_VIDEO_I420_Y_ROWSTRIDE(width) (GST_ROUND_UP_4(width))
#define GST_VIDEO_I420_U_ROWSTRIDE(width) (GST_ROUND_UP_8(width)/2)
#define GST_VIDEO_I420_V_ROWSTRIDE(width) ((GST_ROUND_UP_8(GST_VIDEO_I420_Y_ROWSTRIDE(width)))/2)

#define GST_VIDEO_I420_Y_OFFSET(w,h) (0)
#define GST_VIDEO_I420_U_OFFSET(w,h) (GST_VIDEO_I420_Y_OFFSET(w,h)+(GST_VIDEO_I420_Y_ROWSTRIDE(w)*GST_ROUND_UP_2(h)))
#define GST_VIDEO_I420_V_OFFSET(w,h) (GST_VIDEO_I420_U_OFFSET(w,h)+(GST_VIDEO_I420_U_ROWSTRIDE(w)*GST_ROUND_UP_2(h)/2))
#define GST_VIDEO_I420_SIZE(w,h)     (GST_VIDEO_I420_V_OFFSET(w,h)+(GST_VIDEO_I420_V_ROWSTRIDE(w)*GST_ROUND_UP_2(h)/2))

static gboolean
gst_gamma_set_caps (GstBaseTransform * base, GstCaps * incaps,
    GstCaps * outcaps)
{
  GstGamma *this;
  GstStructure *structure;
  gboolean res;

  this = GST_GAMMA (base);

  GST_DEBUG_OBJECT (this,
      "set_caps: in %" GST_PTR_FORMAT " out %" GST_PTR_FORMAT, incaps, outcaps);

  structure = gst_caps_get_structure (incaps, 0);

  res = gst_structure_get_int (structure, "width", &this->width);
  res &= gst_structure_get_int (structure, "height", &this->height);
  if (!res)
    goto done;

  this->size = GST_VIDEO_I420_SIZE (this->width, this->height);

done:
  return res;
}

static void
gst_gamma_planar411_ip (GstGamma * gamma, guint8 * data, gint size)
{
  oil_tablelookup_u8 (data, 1, data, 1, gamma->gamma_table, 1, size);
}

static GstFlowReturn
gst_gamma_transform_ip (GstBaseTransform * base, GstBuffer * outbuf)
{
  GstGamma *gamma;
  guint8 *data;
  guint size;

  gamma = GST_GAMMA (base);

  if (base->passthrough)
    goto done;

  data = GST_BUFFER_DATA (outbuf);
  size = GST_BUFFER_SIZE (outbuf);

  if (size != gamma->size)
    goto wrong_size;

  gst_gamma_planar411_ip (gamma, data,
      gamma->height * GST_VIDEO_I420_Y_ROWSTRIDE (gamma->width));

done:
  return GST_FLOW_OK;

  /* ERRORS */
wrong_size:
  {
    GST_ELEMENT_ERROR (gamma, STREAM, FORMAT,
        (NULL), ("Invalid buffer size %d, expected %d", size, gamma->size));
    return GST_FLOW_ERROR;
  }
}

static gboolean
plugin_init (GstPlugin * plugin)
{
  GST_DEBUG_CATEGORY_INIT (gamma_debug, "gamma", 0, "gamma");

  return gst_element_register (plugin, "gamma", GST_RANK_NONE, GST_TYPE_GAMMA);
}

GST_PLUGIN_DEFINE (GST_VERSION_MAJOR,
    GST_VERSION_MINOR,
    "gamma",
    "Changes gamma on video images",
    plugin_init, VERSION, GST_LICENSE, GST_PACKAGE_NAME, GST_PACKAGE_ORIGIN);