New morphological operators

CMakeLists.txt

@@ -583,6 +583,10 @@ set(VMIX_RSC_FILES
     ./rsc/shaders/filters/grain.glsl
     ./rsc/shaders/filters/stippling.glsl
     ./rsc/shaders/filters/dithering.glsl
+    ./rsc/shaders/filters/erosion.glsl
+    ./rsc/shaders/filters/dilation.glsl
+    ./rsc/shaders/filters/tophat.glsl
+    ./rsc/shaders/filters/blackhat.glsl
 )
 
 # Include the CMake RC module

ImageFilter.cpp

@@ -99,6 +99,11 @@ std::list< ImageFilter > ImageFilter::presets = {
     ImageFilter("Pixelate", "shaders/filters/pixelate.glsl",   "",     { { "Size", 0.5}, { "Sharpen", 0.5} }),
     ImageFilter("Chromakey","shaders/filters/chromakey.glsl",  "",     { { "Red", 0.05}, { "Green", 0.63}, { "Blue", 0.14}, { "Tolerance", 0.54} }),
     ImageFilter("Fisheye",  "shaders/filters/fisheye.glsl",    "",     { { "Factor", 0.5} }),
+    ImageFilter("Openning", "shaders/filters/erosion.glsl",    "shaders/filters/dilation.glsl",  { { "Radius", 0.5} }),
+    ImageFilter("Closing",  "shaders/filters/dilation.glsl",   "shaders/filters/erosion.glsl",   { { "Radius", 0.5} }),
+    ImageFilter("TopHat",   "shaders/filters/erosion.glsl",    "shaders/filters/tophat.glsl",   { { "Radius", 0.5} }),
+    ImageFilter("BlackHat", "shaders/filters/dilation.glsl",   "shaders/filters/blackhat.glsl",   { { "Radius", 0.5} })
+
 };
 
 

rsc/shaders/filters/blackhat.glsl

@@ -0,0 +1,36 @@
+uniform float Radius;
+#define MAX_SIZE 5
+
+vec3 erosion (sampler2D source, vec2 uv, vec2 uv_step, float R) 
+{
+    vec3 minValue = vec3(1.0);  
+    float D = length(vec2( R / 2.));
+
+    for (float i=-R; i <= R; ++i)
+    {
+        for (float j=-R; j <= R; ++j)
+        {
+            vec2 delta = vec2(i, j);
+            minValue = min(texture(source, uv + delta * smoothstep(R, D, length(delta)) * uv_step ).rgb, minValue); 
+        }
+    }
+
+    return minValue;
+}
+
+void mainImage( out vec4 fragColor, in vec2 fragCoord )
+{
+    vec2 uv = fragCoord.xy / iResolution.xy;
+
+    // blackhat is the difference between the Closing of the input image and the image
+    // Closing is Dilation (first pass) followed by Erosion (second pass)tion.xy;
+
+    // get original image
+    vec3 c = texture(iChannel1, uv).rgb;
+    
+    // get result of Closing
+    vec3 e = erosion(iChannel0, uv, 1.0 / iResolution.xy, mix(1., MAX_SIZE, Radius));
+
+    // composition
+    fragColor = vec4( c + (c-e), 1.0);
+}

rsc/shaders/filters/dilation.glsl

@@ -0,0 +1,25 @@
+uniform float Radius;
+#define MAX_SIZE 5
+
+vec3 dilation (sampler2D source, vec2 uv, vec2 uv_step, float R) {
+    
+    vec3 maxValue = vec3(0.0);
+    float D = length(vec2( R / 2.));
+
+    for (float i=-R; i <= R; ++i)
+    {
+        for (float j=-R; j <= R; ++j)
+        {
+            vec2 delta = vec2(i, j);
+            maxValue = max(texture(source, uv + delta * smoothstep(R, D, length(delta)) * uv_step ).rgb, maxValue); 
+        }
+    }
+
+    return maxValue;
+}
+
+void mainImage( out vec4 fragColor, in vec2 fragCoord )
+{
+    vec2 uv = fragCoord.xy / iResolution.xy;
+    fragColor = vec4( dilation(iChannel0, uv, 1.0 / iResolution.xy, mix(1., MAX_SIZE, Radius)), 1.0);
+}

rsc/shaders/filters/erosion.glsl

@@ -0,0 +1,25 @@
+uniform float Radius;
+#define MAX_SIZE 5
+
+vec3 erosion (sampler2D source, vec2 uv, vec2 uv_step, float R) 
+{
+    vec3 minValue = vec3(1.0);  
+    float D = length(vec2( R / 2.));
+
+    for (float i=-R; i <= R; ++i)
+    {
+        for (float j=-R; j <= R; ++j)
+        {
+            vec2 delta = vec2(i, j);
+            minValue = min(texture(source, uv + delta * smoothstep(R, D, length(delta)) * uv_step ).rgb, minValue); 
+        }
+    }
+
+    return minValue;
+}
+
+void mainImage( out vec4 fragColor, in vec2 fragCoord )
+{
+    vec2 uv = fragCoord.xy / iResolution.xy;
+    fragColor = vec4( erosion(iChannel0, uv, 1.0 / iResolution.xy, mix(1., MAX_SIZE, Radius)), 1.0);
+}

rsc/shaders/filters/tophat.glsl

@@ -0,0 +1,36 @@
+uniform float Radius;
+#define MAX_SIZE 5
+
+vec3 dilation (sampler2D source, vec2 uv, vec2 uv_step, float R) {
+    
+    vec3 maxValue = vec3(0.0);
+    float D = length(vec2( R / 2.));
+
+    for (float i=-R; i <= R; ++i)
+    {
+        for (float j=-R; j <= R; ++j)
+        {
+            vec2 delta = vec2(i, j);
+            maxValue = max(texture(source, uv + delta * smoothstep(R, D, length(delta)) * uv_step ).rgb, maxValue); 
+        }
+    }
+
+    return maxValue;
+}
+
+void mainImage( out vec4 fragColor, in vec2 fragCoord )
+{
+    vec2 uv = fragCoord.xy / iResolution.xy;
+
+    // tophat is the difference between input image and Opening of the input image
+    // Opening is Erosion (first pass) followed by Dilation (second pass)
+
+    // get original image
+    vec3 c = texture(iChannel1, uv).rgb;
+    
+    // get result of Opening
+    vec3 d = dilation(iChannel0, uv, 1.0 / iResolution.xy, mix(1., MAX_SIZE, Radius));
+
+    // composition
+    fragColor = vec4( c + (c-d), 1.0);
+}