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72993f54fa
We are using shaders everywhere and so they are not needed
553 lines
18 KiB
C
553 lines
18 KiB
C
/*
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* GStreamer
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* Copyright (C) 2008 Filippo Argiolas <filippo.argiolas@gmail.com>
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*
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* This library is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Library General Public
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* License as published by the Free Software Foundation; either
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* version 2 of the License, or (at your option) any later version.
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*
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* This library is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Library General Public License for more details.
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*
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* You should have received a copy of the GNU Library General Public
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* License along with this library; if not, write to the
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* Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
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* Boston, MA 02110-1301, USA.
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*/
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/**
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* SECTION:element-gldifferencematte.
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*
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* Saves a background frame and replace it with a pixbuf.
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*
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* <refsect2>
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* <title>Examples</title>
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* |[
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* gst-launch videotestsrc ! glupload ! gldifferencemate location=backgroundimagefile ! glimagesink
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* ]|
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* FBO (Frame Buffer Object) and GLSL (OpenGL Shading Language) are required.
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* </refsect2>
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*/
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#ifdef HAVE_CONFIG_H
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#include "config.h"
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#endif
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#include <stdlib.h>
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#include <png.h>
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#include "gstgldifferencematte.h"
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#include "effects/gstgleffectssources.h"
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#if PNG_LIBPNG_VER >= 10400
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#define int_p_NULL NULL
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#define png_infopp_NULL NULL
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#endif
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#define GST_CAT_DEFAULT gst_gl_differencematte_debug
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GST_DEBUG_CATEGORY_STATIC (GST_CAT_DEFAULT);
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#define DEBUG_INIT \
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GST_DEBUG_CATEGORY_INIT (gst_gl_differencematte_debug, "gldifferencematte", 0, "gldifferencematte element");
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G_DEFINE_TYPE_WITH_CODE (GstGLDifferenceMatte, gst_gl_differencematte,
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GST_TYPE_GL_FILTER, DEBUG_INIT);
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static void gst_gl_differencematte_set_property (GObject * object,
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guint prop_id, const GValue * value, GParamSpec * pspec);
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static void gst_gl_differencematte_get_property (GObject * object,
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guint prop_id, GValue * value, GParamSpec * pspec);
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static gboolean gst_gl_differencematte_filter_texture (GstGLFilter * filter,
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guint in_tex, guint out_tex);
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static gboolean gst_gl_differencematte_loader (GstGLFilter * filter);
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enum
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{
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PROP_0,
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PROP_LOCATION,
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};
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/* init resources that need a gl context */
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static void
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gst_gl_differencematte_init_gl_resources (GstGLFilter * filter)
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{
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GstGLDifferenceMatte *differencematte = GST_GL_DIFFERENCEMATTE (filter);
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GstGLFuncs *gl = GST_GL_BASE_FILTER (filter)->context->gl_vtable;
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gint i;
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for (i = 0; i < 4; i++) {
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gl->GenTextures (1, &differencematte->midtexture[i]);
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gl->BindTexture (GL_TEXTURE_2D, differencematte->midtexture[i]);
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gl->TexImage2D (GL_TEXTURE_2D, 0, GL_RGBA8,
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GST_VIDEO_INFO_WIDTH (&filter->out_info),
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GST_VIDEO_INFO_HEIGHT (&filter->out_info),
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0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);
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gl->TexParameteri (GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
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gl->TexParameteri (GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
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gl->TexParameteri (GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
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gl->TexParameteri (GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
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differencematte->shader[i] =
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gst_gl_shader_new (GST_GL_BASE_FILTER (filter)->context);
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}
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if (!gst_gl_shader_compile_and_check (differencematte->shader[0],
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difference_fragment_source, GST_GL_SHADER_FRAGMENT_SOURCE)) {
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gst_gl_context_set_error (GST_GL_BASE_FILTER (differencematte)->context,
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"Failed to initialize difference shader");
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GST_ELEMENT_ERROR (differencematte, RESOURCE, NOT_FOUND,
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("%s", gst_gl_context_get_error ()), (NULL));
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return;
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}
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if (!gst_gl_shader_compile_and_check (differencematte->shader[1],
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hconv7_fragment_source_opengl, GST_GL_SHADER_FRAGMENT_SOURCE)) {
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gst_gl_context_set_error (GST_GL_BASE_FILTER (differencematte)->context,
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"Failed to initialize hconv7 shader");
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GST_ELEMENT_ERROR (differencematte, RESOURCE, NOT_FOUND,
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("%s", gst_gl_context_get_error ()), (NULL));
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return;
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}
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if (!gst_gl_shader_compile_and_check (differencematte->shader[2],
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vconv7_fragment_source_opengl, GST_GL_SHADER_FRAGMENT_SOURCE)) {
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gst_gl_context_set_error (GST_GL_BASE_FILTER (differencematte)->context,
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"Failed to initialize vconv7 shader");
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GST_ELEMENT_ERROR (differencematte, RESOURCE, NOT_FOUND,
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("%s", gst_gl_context_get_error ()), (NULL));
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return;
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}
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if (!gst_gl_shader_compile_and_check (differencematte->shader[3],
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texture_interp_fragment_source, GST_GL_SHADER_FRAGMENT_SOURCE)) {
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gst_gl_context_set_error (GST_GL_BASE_FILTER (differencematte)->context,
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"Failed to initialize interp shader");
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GST_ELEMENT_ERROR (differencematte, RESOURCE, NOT_FOUND,
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("%s", gst_gl_context_get_error ()), (NULL));
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return;
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}
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}
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/* free resources that need a gl context */
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static void
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gst_gl_differencematte_reset_gl_resources (GstGLFilter * filter)
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{
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GstGLDifferenceMatte *differencematte = GST_GL_DIFFERENCEMATTE (filter);
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GstGLFuncs *gl = GST_GL_BASE_FILTER (filter)->context->gl_vtable;
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gint i;
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gl->DeleteTextures (1, &differencematte->savedbgtexture);
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gl->DeleteTextures (1, &differencematte->newbgtexture);
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for (i = 0; i < 4; i++) {
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if (differencematte->shader[i]) {
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gst_object_unref (differencematte->shader[i]);
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differencematte->shader[i] = NULL;
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}
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if (differencematte->midtexture[i]) {
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gl->DeleteTextures (1, &differencematte->midtexture[i]);
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differencematte->midtexture[i] = 0;
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}
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}
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differencematte->location = NULL;
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differencematte->pixbuf = NULL;
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differencematte->savedbgtexture = 0;
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differencematte->newbgtexture = 0;
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differencematte->bg_has_changed = FALSE;
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}
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static void
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gst_gl_differencematte_class_init (GstGLDifferenceMatteClass * klass)
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{
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GObjectClass *gobject_class;
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GstElementClass *element_class;
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gobject_class = (GObjectClass *) klass;
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element_class = GST_ELEMENT_CLASS (klass);
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gobject_class->set_property = gst_gl_differencematte_set_property;
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gobject_class->get_property = gst_gl_differencematte_get_property;
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GST_GL_FILTER_CLASS (klass)->filter_texture =
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gst_gl_differencematte_filter_texture;
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GST_GL_FILTER_CLASS (klass)->display_init_cb =
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gst_gl_differencematte_init_gl_resources;
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GST_GL_FILTER_CLASS (klass)->display_reset_cb =
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gst_gl_differencematte_reset_gl_resources;
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g_object_class_install_property (gobject_class,
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PROP_LOCATION,
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g_param_spec_string ("location",
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"Background image location",
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"Background image location", NULL,
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G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
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gst_element_class_set_metadata (element_class,
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"Gstreamer OpenGL DifferenceMatte", "Filter/Effect/Video",
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"Saves a background frame and replace it with a pixbuf",
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"Filippo Argiolas <filippo.argiolas@gmail.com>");
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GST_GL_BASE_FILTER_CLASS (klass)->supported_gl_api = GST_GL_API_OPENGL;
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}
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static void
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gst_gl_differencematte_init (GstGLDifferenceMatte * differencematte)
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{
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differencematte->shader[0] = NULL;
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differencematte->shader[1] = NULL;
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differencematte->shader[2] = NULL;
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differencematte->shader[3] = NULL;
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differencematte->location = NULL;
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differencematte->pixbuf = NULL;
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differencematte->savedbgtexture = 0;
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differencematte->newbgtexture = 0;
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differencematte->bg_has_changed = FALSE;
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fill_gaussian_kernel (differencematte->kernel, 7, 30.0);
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}
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static void
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gst_gl_differencematte_set_property (GObject * object, guint prop_id,
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const GValue * value, GParamSpec * pspec)
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{
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GstGLDifferenceMatte *differencematte = GST_GL_DIFFERENCEMATTE (object);
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switch (prop_id) {
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case PROP_LOCATION:
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if (differencematte->location != NULL)
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g_free (differencematte->location);
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differencematte->bg_has_changed = TRUE;
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differencematte->location = g_value_dup_string (value);
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break;
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default:
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G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
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break;
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}
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}
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static void
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gst_gl_differencematte_get_property (GObject * object, guint prop_id,
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GValue * value, GParamSpec * pspec)
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{
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GstGLDifferenceMatte *differencematte = GST_GL_DIFFERENCEMATTE (object);
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switch (prop_id) {
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case PROP_LOCATION:
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g_value_set_string (value, differencematte->location);
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break;
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default:
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G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
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break;
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}
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}
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static void
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gst_gl_differencematte_save_texture (gint width, gint height, guint texture,
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gpointer stuff)
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{
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GstGLFilter *filter = GST_GL_FILTER (stuff);
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GstGLFuncs *gl = GST_GL_BASE_FILTER (filter)->context->gl_vtable;
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gl->MatrixMode (GL_PROJECTION);
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gl->LoadIdentity ();
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gst_gl_filter_draw_texture (filter, texture, width, height);
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}
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static void
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init_pixbuf_texture (GstGLContext * context, gpointer data)
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{
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GstGLDifferenceMatte *differencematte = GST_GL_DIFFERENCEMATTE (data);
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GstGLFilter *filter = GST_GL_FILTER (data);
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GstGLFuncs *gl = GST_GL_BASE_FILTER (filter)->context->gl_vtable;
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gl->DeleteTextures (1, &differencematte->newbgtexture);
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gl->GenTextures (1, &differencematte->newbgtexture);
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gl->BindTexture (GL_TEXTURE_2D, differencematte->newbgtexture);
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gl->TexImage2D (GL_TEXTURE_2D, 0, GL_RGBA,
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(gint) differencematte->pbuf_width, (gint) differencematte->pbuf_height,
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0, GL_RGBA, GL_UNSIGNED_BYTE, differencematte->pixbuf);
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gl->TexParameteri (GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
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gl->TexParameteri (GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
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gl->TexParameteri (GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
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gl->TexParameteri (GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
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if (differencematte->savedbgtexture == 0) {
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gl->GenTextures (1, &differencematte->savedbgtexture);
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gl->BindTexture (GL_TEXTURE_2D, differencematte->savedbgtexture);
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gl->TexImage2D (GL_TEXTURE_2D, 0, GL_RGBA8,
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GST_VIDEO_INFO_WIDTH (&filter->out_info),
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GST_VIDEO_INFO_HEIGHT (&filter->out_info),
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0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);
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gl->TexParameteri (GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
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gl->TexParameteri (GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
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gl->TexParameteri (GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
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gl->TexParameteri (GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
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}
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}
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static void
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gst_gl_differencematte_diff (gint width, gint height, guint texture,
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gpointer stuff)
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{
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GstGLDifferenceMatte *differencematte = GST_GL_DIFFERENCEMATTE (stuff);
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GstGLFilter *filter = GST_GL_FILTER (stuff);
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GstGLFuncs *gl = GST_GL_BASE_FILTER (filter)->context->gl_vtable;
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gl->MatrixMode (GL_PROJECTION);
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gl->LoadIdentity ();
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gst_gl_shader_use (differencematte->shader[0]);
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gl->ActiveTexture (GL_TEXTURE0);
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gl->BindTexture (GL_TEXTURE_2D, texture);
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gst_gl_shader_set_uniform_1i (differencematte->shader[0], "current", 0);
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gl->ActiveTexture (GL_TEXTURE1);
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gl->BindTexture (GL_TEXTURE_2D, differencematte->savedbgtexture);
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gst_gl_shader_set_uniform_1i (differencematte->shader[0], "saved", 1);
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gst_gl_filter_draw_texture (filter, texture, width, height);
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}
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static void
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gst_gl_differencematte_hblur (gint width, gint height, guint texture,
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gpointer stuff)
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{
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GstGLDifferenceMatte *differencematte = GST_GL_DIFFERENCEMATTE (stuff);
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GstGLFilter *filter = GST_GL_FILTER (stuff);
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GstGLFuncs *gl = GST_GL_BASE_FILTER (filter)->context->gl_vtable;
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gl->MatrixMode (GL_PROJECTION);
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gl->LoadIdentity ();
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gst_gl_shader_use (differencematte->shader[1]);
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gl->ActiveTexture (GL_TEXTURE0);
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gl->BindTexture (GL_TEXTURE_2D, texture);
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gst_gl_shader_set_uniform_1i (differencematte->shader[1], "tex", 0);
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gst_gl_shader_set_uniform_1fv (differencematte->shader[1], "kernel", 7,
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differencematte->kernel);
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gst_gl_shader_set_uniform_1f (differencematte->shader[1], "width", width);
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gst_gl_filter_draw_texture (filter, texture, width, height);
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}
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static void
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gst_gl_differencematte_vblur (gint width, gint height, guint texture,
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gpointer stuff)
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{
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GstGLDifferenceMatte *differencematte = GST_GL_DIFFERENCEMATTE (stuff);
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GstGLFilter *filter = GST_GL_FILTER (stuff);
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GstGLFuncs *gl = GST_GL_BASE_FILTER (filter)->context->gl_vtable;
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gl->MatrixMode (GL_PROJECTION);
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gl->LoadIdentity ();
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gst_gl_shader_use (differencematte->shader[2]);
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gl->ActiveTexture (GL_TEXTURE0);
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gl->BindTexture (GL_TEXTURE_2D, texture);
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gst_gl_shader_set_uniform_1i (differencematte->shader[2], "tex", 0);
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gst_gl_shader_set_uniform_1fv (differencematte->shader[2], "kernel", 7,
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differencematte->kernel);
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gst_gl_shader_set_uniform_1f (differencematte->shader[2], "height", height);
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gst_gl_filter_draw_texture (filter, texture, width, height);
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}
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static void
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gst_gl_differencematte_interp (gint width, gint height, guint texture,
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gpointer stuff)
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{
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GstGLDifferenceMatte *differencematte = GST_GL_DIFFERENCEMATTE (stuff);
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GstGLFilter *filter = GST_GL_FILTER (stuff);
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GstGLFuncs *gl = GST_GL_BASE_FILTER (filter)->context->gl_vtable;
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gl->MatrixMode (GL_PROJECTION);
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glLoadIdentity ();
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gst_gl_shader_use (differencematte->shader[3]);
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gl->ActiveTexture (GL_TEXTURE0);
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gl->BindTexture (GL_TEXTURE_2D, texture);
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gst_gl_shader_set_uniform_1i (differencematte->shader[3], "blend", 0);
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gl->ActiveTexture (GL_TEXTURE1);
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gl->BindTexture (GL_TEXTURE_2D, differencematte->newbgtexture);
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gst_gl_shader_set_uniform_1i (differencematte->shader[3], "base", 1);
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gl->ActiveTexture (GL_TEXTURE2);
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gl->BindTexture (GL_TEXTURE_2D, differencematte->midtexture[2]);
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gst_gl_shader_set_uniform_1i (differencematte->shader[3], "alpha", 2);
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gst_gl_filter_draw_texture (filter, texture, width, height);
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}
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static void
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gst_gl_differencematte_identity (gint width, gint height, guint texture,
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gpointer stuff)
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{
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GstGLDifferenceMatte *differencematte = GST_GL_DIFFERENCEMATTE (stuff);
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GstGLFilter *filter = GST_GL_FILTER (differencematte);
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GstGLFuncs *gl = GST_GL_BASE_FILTER (filter)->context->gl_vtable;
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gl->MatrixMode (GL_PROJECTION);
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gl->LoadIdentity ();
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gst_gl_filter_draw_texture (filter, texture, width, height);
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}
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static gboolean
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gst_gl_differencematte_filter_texture (GstGLFilter * filter, guint in_tex,
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guint out_tex)
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{
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GstGLDifferenceMatte *differencematte = GST_GL_DIFFERENCEMATTE (filter);
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differencematte->intexture = in_tex;
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if (differencematte->bg_has_changed && (differencematte->location != NULL)) {
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if (!gst_gl_differencematte_loader (filter))
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differencematte->pixbuf = NULL;
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/* if loader failed then context is turned off */
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gst_gl_context_thread_add (GST_GL_BASE_FILTER (filter)->context,
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init_pixbuf_texture, differencematte);
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/* save current frame, needed to calculate difference between
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* this frame and next ones */
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gst_gl_filter_render_to_target (filter, TRUE, in_tex,
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differencematte->savedbgtexture,
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gst_gl_differencematte_save_texture, differencematte);
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if (differencematte->pixbuf) {
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free (differencematte->pixbuf);
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differencematte->pixbuf = NULL;
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}
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|
|
differencematte->bg_has_changed = FALSE;
|
|
}
|
|
|
|
if (differencematte->savedbgtexture != 0) {
|
|
gst_gl_filter_render_to_target (filter, TRUE, in_tex,
|
|
differencematte->midtexture[0], gst_gl_differencematte_diff,
|
|
differencematte);
|
|
gst_gl_filter_render_to_target (filter, FALSE,
|
|
differencematte->midtexture[0], differencematte->midtexture[1],
|
|
gst_gl_differencematte_hblur, differencematte);
|
|
gst_gl_filter_render_to_target (filter, FALSE,
|
|
differencematte->midtexture[1], differencematte->midtexture[2],
|
|
gst_gl_differencematte_vblur, differencematte);
|
|
gst_gl_filter_render_to_target (filter, TRUE, in_tex, out_tex,
|
|
gst_gl_differencematte_interp, differencematte);
|
|
} else {
|
|
gst_gl_filter_render_to_target (filter, TRUE, in_tex, out_tex,
|
|
gst_gl_differencematte_identity, differencematte);
|
|
}
|
|
|
|
return TRUE;
|
|
}
|
|
|
|
static void
|
|
user_warning_fn (png_structp png_ptr, png_const_charp warning_msg)
|
|
{
|
|
g_warning ("%s\n", warning_msg);
|
|
}
|
|
|
|
#define LOAD_ERROR(msg) { GST_WARNING ("unable to load %s: %s", differencematte->location, msg); return FALSE; }
|
|
|
|
static gboolean
|
|
gst_gl_differencematte_loader (GstGLFilter * filter)
|
|
{
|
|
GstGLDifferenceMatte *differencematte = GST_GL_DIFFERENCEMATTE (filter);
|
|
|
|
png_structp png_ptr;
|
|
png_infop info_ptr;
|
|
guint sig_read = 0;
|
|
png_uint_32 width = 0;
|
|
png_uint_32 height = 0;
|
|
gint bit_depth = 0;
|
|
gint color_type = 0;
|
|
gint interlace_type = 0;
|
|
png_FILE_p fp = NULL;
|
|
guint y = 0;
|
|
guchar **rows = NULL;
|
|
gint filler;
|
|
|
|
if (!GST_GL_BASE_FILTER (filter)->context)
|
|
return TRUE;
|
|
|
|
if ((fp = fopen (differencematte->location, "rb")) == NULL)
|
|
LOAD_ERROR ("file not found");
|
|
|
|
png_ptr = png_create_read_struct (PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
|
|
|
|
if (png_ptr == NULL) {
|
|
fclose (fp);
|
|
LOAD_ERROR ("failed to initialize the png_struct");
|
|
}
|
|
|
|
png_set_error_fn (png_ptr, NULL, NULL, user_warning_fn);
|
|
|
|
info_ptr = png_create_info_struct (png_ptr);
|
|
if (info_ptr == NULL) {
|
|
fclose (fp);
|
|
png_destroy_read_struct (&png_ptr, png_infopp_NULL, png_infopp_NULL);
|
|
LOAD_ERROR ("failed to initialize the memory for image information");
|
|
}
|
|
|
|
png_init_io (png_ptr, fp);
|
|
|
|
png_set_sig_bytes (png_ptr, sig_read);
|
|
|
|
png_read_info (png_ptr, info_ptr);
|
|
|
|
png_get_IHDR (png_ptr, info_ptr, &width, &height, &bit_depth, &color_type,
|
|
&interlace_type, int_p_NULL, int_p_NULL);
|
|
|
|
if (color_type == PNG_COLOR_TYPE_RGB) {
|
|
filler = 0xff;
|
|
png_set_filler (png_ptr, filler, PNG_FILLER_AFTER);
|
|
color_type = PNG_COLOR_TYPE_RGB_ALPHA;
|
|
}
|
|
|
|
if (color_type != PNG_COLOR_TYPE_RGB_ALPHA) {
|
|
fclose (fp);
|
|
png_destroy_read_struct (&png_ptr, png_infopp_NULL, png_infopp_NULL);
|
|
LOAD_ERROR ("color type is not rgb");
|
|
}
|
|
|
|
differencematte->pbuf_width = width;
|
|
differencematte->pbuf_height = height;
|
|
|
|
differencematte->pixbuf =
|
|
(guchar *) malloc (sizeof (guchar) * width * height * 4);
|
|
|
|
rows = (guchar **) malloc (sizeof (guchar *) * height);
|
|
|
|
for (y = 0; y < height; ++y)
|
|
rows[y] = (guchar *) (differencematte->pixbuf + y * width * 4);
|
|
|
|
png_read_image (png_ptr, rows);
|
|
|
|
free (rows);
|
|
|
|
png_read_end (png_ptr, info_ptr);
|
|
png_destroy_read_struct (&png_ptr, &info_ptr, png_infopp_NULL);
|
|
fclose (fp);
|
|
|
|
return TRUE;
|
|
}
|