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Diffstat (limited to 'app/operations/gimpoperationlevels.c')
| -rw-r--r-- | app/operations/gimpoperationlevels.c | 208 |
1 files changed, 208 insertions, 0 deletions
diff --git a/app/operations/gimpoperationlevels.c b/app/operations/gimpoperationlevels.c new file mode 100644 index 0000000..1bf0b06 --- /dev/null +++ b/app/operations/gimpoperationlevels.c @@ -0,0 +1,208 @@ +/* GIMP - The GNU Image Manipulation Program + * Copyright (C) 1995 Spencer Kimball and Peter Mattis + * + * gimpoperationlevels.c + * Copyright (C) 2007 Michael Natterer <mitch@gimp.org> + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 3 of the License, or + * (at your option) any later version. + * + * This program 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 General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <https://www.gnu.org/licenses/>. + */ + +#include "config.h" + +#include <cairo.h> +#include <gdk-pixbuf/gdk-pixbuf.h> +#include <gegl.h> + +#include "libgimpmath/gimpmath.h" + +#include "operations-types.h" + +#include "gimplevelsconfig.h" +#include "gimpoperationlevels.h" + +#include "gimp-intl.h" + + +static gboolean gimp_operation_levels_process (GeglOperation *operation, + void *in_buf, + void *out_buf, + glong samples, + const GeglRectangle *roi, + gint level); + + +G_DEFINE_TYPE (GimpOperationLevels, gimp_operation_levels, + GIMP_TYPE_OPERATION_POINT_FILTER) + +#define parent_class gimp_operation_levels_parent_class + + +static void +gimp_operation_levels_class_init (GimpOperationLevelsClass *klass) +{ + GObjectClass *object_class = G_OBJECT_CLASS (klass); + GeglOperationClass *operation_class = GEGL_OPERATION_CLASS (klass); + GeglOperationPointFilterClass *point_class = GEGL_OPERATION_POINT_FILTER_CLASS (klass); + + object_class->set_property = gimp_operation_point_filter_set_property; + object_class->get_property = gimp_operation_point_filter_get_property; + + gegl_operation_class_set_keys (operation_class, + "name", "gimp:levels", + "categories", "color", + "description", _("Adjust color levels"), + NULL); + + point_class->process = gimp_operation_levels_process; + + g_object_class_install_property (object_class, + GIMP_OPERATION_POINT_FILTER_PROP_LINEAR, + g_param_spec_boolean ("linear", + "Linear", + "Whether to operate on linear RGB", + FALSE, + G_PARAM_READWRITE)); + + g_object_class_install_property (object_class, + GIMP_OPERATION_POINT_FILTER_PROP_CONFIG, + g_param_spec_object ("config", + "Config", + "The config object", + GIMP_TYPE_LEVELS_CONFIG, + G_PARAM_READWRITE | + G_PARAM_CONSTRUCT)); +} + +static void +gimp_operation_levels_init (GimpOperationLevels *self) +{ +} + +static inline gdouble +gimp_operation_levels_map (gdouble value, + gdouble low_input, + gdouble high_input, + gboolean clamp_input, + gdouble inv_gamma, + gdouble low_output, + gdouble high_output, + gboolean clamp_output) +{ + /* determine input intensity */ + if (high_input != low_input) + value = (value - low_input) / (high_input - low_input); + else + value = (value - low_input); + + if (clamp_input) + value = CLAMP (value, 0.0, 1.0); + + if (inv_gamma != 1.0 && value > 0) + value = pow (value, inv_gamma); + + /* determine the output intensity */ + if (high_output >= low_output) + value = value * (high_output - low_output) + low_output; + else if (high_output < low_output) + value = low_output - value * (low_output - high_output); + + if (clamp_output) + value = CLAMP (value, 0.0, 1.0); + + return value; +} + +static gboolean +gimp_operation_levels_process (GeglOperation *operation, + void *in_buf, + void *out_buf, + glong samples, + const GeglRectangle *roi, + gint level) +{ + GimpOperationPointFilter *point = GIMP_OPERATION_POINT_FILTER (operation); + GimpLevelsConfig *config = GIMP_LEVELS_CONFIG (point->config); + gfloat *src = in_buf; + gfloat *dest = out_buf; + gfloat inv_gamma[5]; + gint channel; + + if (! config) + return FALSE; + + for (channel = 0; channel < 5; channel++) + { + g_return_val_if_fail (config->gamma[channel] != 0.0, FALSE); + + inv_gamma[channel] = 1.0 / config->gamma[channel]; + } + + while (samples--) + { + for (channel = 0; channel < 4; channel++) + { + gdouble value; + + value = gimp_operation_levels_map (src[channel], + config->low_input[channel + 1], + config->high_input[channel + 1], + config->clamp_input, + inv_gamma[channel + 1], + config->low_output[channel + 1], + config->high_output[channel + 1], + config->clamp_output); + + /* don't apply the overall curve to the alpha channel */ + if (channel != ALPHA) + value = gimp_operation_levels_map (value, + config->low_input[0], + config->high_input[0], + config->clamp_input, + inv_gamma[0], + config->low_output[0], + config->high_output[0], + config->clamp_output); + + dest[channel] = value; + } + + src += 4; + dest += 4; + } + + return TRUE; +} + + +/* public functions */ + +gdouble +gimp_operation_levels_map_input (GimpLevelsConfig *config, + GimpHistogramChannel channel, + gdouble value) +{ + g_return_val_if_fail (GIMP_IS_LEVELS_CONFIG (config), 0.0); + + /* determine input intensity */ + if (config->high_input[channel] != config->low_input[channel]) + value = ((value - config->low_input[channel]) / + (config->high_input[channel] - config->low_input[channel])); + else + value = (value - config->low_input[channel]); + + if (config->gamma[channel] != 0.0 && value > 0.0) + value = pow (value, 1.0 / config->gamma[channel]); + + return value; +} |