../operations/common/brightness-contrast.c
/* This file is an image processing operation for GEGL
*
* GEGL 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.
*
* GEGL 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 GEGL; if not, see <http://www.gnu.org/licenses/>.
*
* Copyright 2006 Øyvind Kolås <pippin@gimp.org>
*/
#include "config.h"
#include <glib/gi18n-lib.h>
/* Followed by this #if ... */
#ifdef GEGL_CHANT_PROPERTIES
/* ... are the properties of the filter, these are all scalar values
* (doubles), the the parameters are:
* property name, min, max, default, "description of property"
*/
gegl_chant_double_ui (contrast, _("Contrast"), -5.0, 5.0, 1.0, 0.0, 2.0, 1.0,
_("Range scale factor"))
gegl_chant_double_ui (brightness, _("Brightness"), -3.0, 3.0, 0.0, -1.0, 1.0, 1.0,
_("Amount to increase brightness"))
/* this will create the instance structure for our use, and register the
* property with the given ranges, default values and a comment for the
* documentation/tooltip.
*/
#else
/* Specify the base class we're building our operation on, the base
* class provides a lot of the legwork so we do not have to. For
* brightness contrast the best base class is the POINT_FILTER base
* class.
*/
#define GEGL_CHANT_TYPE_POINT_FILTER
/* We specify the file we're in, this is needed to make the code
* generation for the properties work.
*/
#define GEGL_CHANT_C_FILE "brightness-contrast.c"
/* Including gegl-chant.h creates most of the GObject boiler plate
* needed, creating a GeglChant instance structure a GeglChantClass
* structure for our operation, as well as the needed code to register
* our new gobject with GEGL.
*/
#include "gegl-chant.h"
/* prepare() is called on each operation providing data to a node that
* is requested to provide a rendered result. When prepare is called
* all properties are known. For brightness contrast we use this
* opportunity to dictate the formats of the input and output buffers.
*/
static void prepare (GeglOperation *operation)
{
gegl_operation_set_format (operation, "input", babl_format ("RGBA float"));
gegl_operation_set_format (operation, "output", babl_format ("RGBA float"));
}
/* For GeglOperationPointFilter subclasses, we operate on linear
* buffers with a pixel count.
*/
static gboolean
process (GeglOperation *op,
void *in_buf,
void *out_buf,
glong n_pixels,
const GeglRectangle *roi,
gint level)
{
/* Retrieve a pointer to GeglChantO structure which contains all the
* chanted properties
*/
GeglChantO *o = GEGL_CHANT_PROPERTIES (op);
gfloat * GEGL_ALIGNED in_pixel;
gfloat * GEGL_ALIGNED out_pixel;
gfloat brightness, contrast;
glong i;
in_pixel = in_buf;
out_pixel = out_buf;
brightness = o->brightness;
contrast = o->contrast;
for (i=0; i<n_pixels; i++)
{
out_pixel[0] = (in_pixel[0] - 0.5f) * contrast + brightness + 0.5;
out_pixel[1] = (in_pixel[1] - 0.5f) * contrast + brightness + 0.5;
out_pixel[2] = (in_pixel[2] - 0.5f) * contrast + brightness + 0.5;
out_pixel[3] = in_pixel[3]; /* copy the alpha */
in_pixel += 4;
out_pixel += 4;
}
return TRUE;
}
#include "opencl/gegl-cl.h"
static const char* kernel_source =
"__kernel void kernel_bc(__global const float4 *in, \n"
" __global float4 *out, \n"
" float brightness, \n"
" float contrast) \n"
"{ \n"
" int gid = get_global_id(0); \n"
" float4 in_v = in[gid]; \n"
" float4 out_v; \n"
" out_v.xyz = (in_v.xyz - 0.5f) * contrast + brightness + 0.5f;\n"
" out_v.w = in_v.w; \n"
" out[gid] = out_v; \n"
"} \n";
static gegl_cl_run_data *cl_data = NULL;
/* OpenCL processing function */
static cl_int
cl_process (GeglOperation *op,
cl_mem in_tex,
cl_mem out_tex,
size_t global_worksize,
const GeglRectangle *roi,
int level)
{
/* Retrieve a pointer to GeglChantO structure which contains all the
* chanted properties
*/
GeglChantO *o = GEGL_CHANT_PROPERTIES (op);
gfloat brightness = o->brightness;
gfloat contrast = o->contrast;
cl_int cl_err = 0;
if (!cl_data)
{
const char *kernel_name[] = {"kernel_bc", NULL};
cl_data = gegl_cl_compile_and_build (kernel_source, kernel_name);
}
if (!cl_data) return 1;
cl_err |= gegl_clSetKernelArg(cl_data->kernel[0], 0, sizeof(cl_mem), (void*)&in_tex);
cl_err |= gegl_clSetKernelArg(cl_data->kernel[0], 1, sizeof(cl_mem), (void*)&out_tex);
cl_err |= gegl_clSetKernelArg(cl_data->kernel[0], 2, sizeof(cl_float), (void*)&brightness);
cl_err |= gegl_clSetKernelArg(cl_data->kernel[0], 3, sizeof(cl_float), (void*)&contrast);
if (cl_err != CL_SUCCESS) return cl_err;
cl_err = gegl_clEnqueueNDRangeKernel(gegl_cl_get_command_queue (),
cl_data->kernel[0], 1,
NULL, &global_worksize, NULL,
0, NULL, NULL);
if (cl_err != CL_SUCCESS) return cl_err;
return cl_err;
}
/*
* The class init function sets up information needed for this operations class
* (template) in the GObject OO framework.
*/
static void
gegl_chant_class_init (GeglChantClass *klass)
{
GeglOperationClass *operation_class;
GeglOperationPointFilterClass *point_filter_class;
operation_class = GEGL_OPERATION_CLASS (klass);
point_filter_class = GEGL_OPERATION_POINT_FILTER_CLASS (klass);
/* override the prepare methods of the GeglOperation class */
operation_class->prepare = prepare;
/* override the process method of the point filter class (the process methods
* of our superclasses deal with the handling on their level of abstraction)
*/
point_filter_class->process = process;
point_filter_class->cl_process = cl_process;
/* specify the name this operation is found under in the GUI/when
* programming/in XML
*/
operation_class->opencl_support = TRUE;
gegl_operation_class_set_keys (operation_class,
"name", "gegl:brightness-contrast",
"categories", "color",
"description", _("Changes the light level and contrast."),
NULL);
}
#endif /* closing #ifdef GEGL_CHANT_PROPERTIES ... else ... */
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