diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8f5587a..2350aa1 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -600,6 +600,7 @@ set(VMIX_RSC_FILES
     ./rsc/shaders/filters/resample_double.glsl
     ./rsc/shaders/filters/resample_half.glsl
     ./rsc/shaders/filters/resample_quarter.glsl
+    ./rsc/shaders/filters/earlybird.glsl
 )
 
 # Include the CMake RC module
diff --git a/ImageFilter.cpp b/ImageFilter.cpp
index f8249e8..c70c7d2 100644
--- a/ImageFilter.cpp
+++ b/ImageFilter.cpp
@@ -65,8 +65,9 @@ std::string fragmentFooter = "void main() {\n"
 
 std::list< FilteringProgram > FilteringProgram::presets = {
     FilteringProgram(),
-    FilteringProgram("Bilateral","shaders/filters/bilinear.glsl",   "",     { }),
+    FilteringProgram("Bilateral","shaders/filters/focus.glsl",      "",     { }),
     FilteringProgram("Pixelate", "shaders/filters/pixelate.glsl",   "",     { }),
+    FilteringProgram("Earlybird","shaders/filters/earlybird.glsl",  "",     { }),
     FilteringProgram("Bloom",    "shaders/filters/bloom.glsl",      "",     { }),
     FilteringProgram("Bokeh",    "shaders/filters/bokeh.glsl",      "",     { }),
     FilteringProgram("Talk",     "shaders/filters/talk.glsl",       "",     { }),
@@ -714,7 +715,7 @@ const char* SmoothFilter::method_label[SmoothFilter::SMOOTH_INVALID] = {
 };
 
 std::vector< FilteringProgram > SmoothFilter::programs_ = {
-    FilteringProgram("Bilateral","shaders/filters/focus.glsl",      "",     { { "Factor", 0.5} }),
+    FilteringProgram("Bilateral","shaders/filters/bilinear.glsl",   "",     { { "Factor", 0.5} }),
     FilteringProgram("Kuwahara", "shaders/filters/kuwahara.glsl",   "",     { { "Radius", 1.0} }),
     FilteringProgram("Opening",  "shaders/filters/erosion.glsl",    "shaders/filters/dilation.glsl",  { { "Radius", 0.5} }),
     FilteringProgram("Closing",  "shaders/filters/dilation.glsl",   "shaders/filters/erosion.glsl",   { { "Radius", 0.5} }),
@@ -764,7 +765,7 @@ const char* EdgeFilter::method_label[EdgeFilter::EDGE_INVALID] = {
 std::vector< FilteringProgram > EdgeFilter::programs_ = {
     FilteringProgram("Sobel",    "shaders/filters/sobel.glsl",      "",     { { "Factor", 0.5} }),
     FilteringProgram("Freichen", "shaders/filters/freichen.glsl",   "",     { { "Factor", 0.5} }),
-    FilteringProgram("Edge",     "shaders/filters/bilinear.glsl",   "shaders/filters/edge.glsl",     { { "Threshold", 0.5} }),
+    FilteringProgram("Edge",     "shaders/filters/focus.glsl",      "shaders/filters/edge.glsl",     { { "Threshold", 0.5} }),
     FilteringProgram("Contour",  "shaders/filters/sharpen_1.glsl",  "shaders/filters/contour_2.glsl",     { { "Amount", 0.5} }),
 };
 
diff --git a/rsc/shaders/filters/bilinear.glsl b/rsc/shaders/filters/bilinear.glsl
index 8f5d572..2405780 100644
--- a/rsc/shaders/filters/bilinear.glsl
+++ b/rsc/shaders/filters/bilinear.glsl
@@ -1,53 +1,42 @@
-#define SIGMA 10.0
-#define BSIGMA 0.1
+// Fast simple bilinear RGBA filter
+// by Bruno Herbelin
 
-float kernel[15];
+#define SIGMA 10.0
+
+uniform float Factor;
+
+float kernel[15] = {0.031225216, 0.033322271, 0.035206333, 0.036826804, 0.038138565,
+0.039104044, 0.039695028, 0.039894000, 0.039695028, 0.039104044,
+0.038138565, 0.036826804, 0.035206333, 0.033322271, 0.031225216 };
 
 float normpdf(in float x, in float sigma)
 {
-	return 0.39894*exp(-0.5*x*x/(sigma*sigma))/sigma;
+    return 0.39894*exp(-0.5*x*x/(sigma*sigma))/sigma;
 }
 
-float normpdf3(in vec3 v, in float sigma)
+float normpdf3(in vec4 v, in float sigma)
 {
-	return 0.39894*exp(-0.5*dot(v,v)/(sigma*sigma))/sigma;
+    return 0.39894*exp(-0.5*dot(v,v)/(sigma*sigma))/sigma;
 }
 
 void mainImage( out vec4 fragColor, in vec2 fragCoord )
 {
-    vec3 c = texture(iChannel0, (fragCoord.xy / iResolution.xy)).rgb;
-   
-    kernel[0] = 0.031225216;
-    kernel[1] = 0.033322271;
-    kernel[2] = 0.035206333;
-    kernel[3] = 0.036826804;
-    kernel[4] = 0.038138565;
-    kernel[5] = 0.039104044;
-    kernel[6] = 0.039695028;
-    kernel[7] = 0.039894000;
-    kernel[8] = 0.039695028;
-    kernel[9] = 0.039104044;
-    kernel[10] = 0.038138565;
-    kernel[11] = 0.036826804;
-    kernel[12] = 0.035206333;
-    kernel[13] = 0.033322271;
-    kernel[14] = 0.031225216;
-    
-    vec3 final_colour = vec3(0.0);
+    vec4 O = vec4(0.0);
     float Z = 0.0;
-    vec3 cc;
-    float f;
-    float bZ = 1.0/normpdf(0.0, mix(BSIGMA, 1.0, .0) );
-    
+    vec4 cc;
+    float bsigma = mix(0.01, 0.5, Factor);
+    float bZ = 1.0/normpdf(0.0, mix(bsigma, 1.0, .0) );
+    vec4 C = texture(iChannel0, (fragCoord.xy / iResolution.xy));
+
     for (int i = -7; i <= 7; ++i)
     {
         for (int j = -7; j <= 7; ++j)
         {
-            cc = texture(iChannel0, (fragCoord.xy+vec2(float(i),float(j))) / iResolution.xy).rgb;
-            f = normpdf3(cc-c, mix(BSIGMA, 1.0, .0) ) * bZ * kernel[7+j] * kernel[7+i];
+            cc = texture(iChannel0, (fragCoord+vec2(float(i),float(j))) / iResolution.xy);
+            float f = normpdf3(cc -C, mix(bsigma, 1.0, .0) ) * bZ * kernel[7+j] * kernel[7+i];
             Z += f;
-            final_colour += f*cc;
+            O += f*cc;
         }
     }
-    fragColor = vec4(final_colour/Z, 1.0);
+    fragColor = O/Z;
 }
diff --git a/rsc/shaders/filters/blackhat.glsl b/rsc/shaders/filters/blackhat.glsl
index 213c056..14c83f2 100644
--- a/rsc/shaders/filters/blackhat.glsl
+++ b/rsc/shaders/filters/blackhat.glsl
@@ -1,3 +1,9 @@
+/*
+ * This file is part of vimix - video live mixer
+ * https://github.com/brunoherbelin/vimix
+ * (C) 2019-2022 Bruno Herbelin <bruno.herbelin@gmail.com>
+ * Distributed under GNU GPL3+ License
+**/
 uniform float Radius;
 #define MAX_SIZE 5
 
diff --git a/rsc/shaders/filters/blur_1.glsl b/rsc/shaders/filters/blur_1.glsl
index fd208de..0dc3626 100644
--- a/rsc/shaders/filters/blur_1.glsl
+++ b/rsc/shaders/filters/blur_1.glsl
@@ -1,5 +1,9 @@
-// Gaussian blur with mipmapping
-// Bruno Herbelin
+/*
+ * This file is part of vimix - video live mixer
+ * https://github.com/brunoherbelin/vimix
+ * (C) 2019-2022 Bruno Herbelin <bruno.herbelin@gmail.com>
+ * Distributed under GNU GPL3+ License
+**/
 // Following tutorial https://www.shadertoy.com/view/WtKfD3
 
 #define N 13
diff --git a/rsc/shaders/filters/blur_2.glsl b/rsc/shaders/filters/blur_2.glsl
index 917b00f..65eff71 100644
--- a/rsc/shaders/filters/blur_2.glsl
+++ b/rsc/shaders/filters/blur_2.glsl
@@ -1,3 +1,9 @@
+/*
+ * This file is part of vimix - video live mixer
+ * https://github.com/brunoherbelin/vimix
+ * (C) 2019-2022 Bruno Herbelin <bruno.herbelin@gmail.com>
+ * Distributed under GNU GPL3+ License
+**/
 // Following tutorial https://www.shadertoy.com/view/WtKfD3
 
 #define N 13
diff --git a/rsc/shaders/filters/chromakey.glsl b/rsc/shaders/filters/chromakey.glsl
index 4daf959..d7b248d 100644
--- a/rsc/shaders/filters/chromakey.glsl
+++ b/rsc/shaders/filters/chromakey.glsl
@@ -1,14 +1,11 @@
 /*
-chroma key algorithm used to remove the greens screen
-this technique is nice as you can choose a color removal range.
-using this range, the algorithm will either remove the given color
-or blend it with background
+ * This file is part of vimix - video live mixer
+ * https://github.com/brunoherbelin/vimix
+ * (C) 2019-2022 Bruno Herbelin <bruno.herbelin@gmail.com>
+ * Distributed under GNU GPL3+ License
+**/
+// Inspired by https://www.shadertoy.com/view/MlVXWD by tudordot
 
-because of this, difficult parts (ie. the sword) can either have a
-green-ish look or are a bit transparent (hard to catch with a lot of movement)
-
-(c) tudordot from https://www.shadertoy.com/view/MlVXWD
-*/
 
 uniform float Red;
 uniform float Green;
diff --git a/rsc/shaders/filters/circularblur.glsl b/rsc/shaders/filters/circularblur.glsl
index 2e3400a..c18cf7f 100644
--- a/rsc/shaders/filters/circularblur.glsl
+++ b/rsc/shaders/filters/circularblur.glsl
@@ -1,3 +1,10 @@
+/*
+ * This file is part of vimix - video live mixer
+ * https://github.com/brunoherbelin/vimix
+ * (C) 2019-2022 Bruno Herbelin <bruno.herbelin@gmail.com>
+ * Distributed under GNU GPL3+ License
+**/
+
 #define TWOPI 6.28318530718
 
 uniform float Radius;
diff --git a/rsc/shaders/filters/coloralpha.glsl b/rsc/shaders/filters/coloralpha.glsl
index d87d39d..91a4e52 100644
--- a/rsc/shaders/filters/coloralpha.glsl
+++ b/rsc/shaders/filters/coloralpha.glsl
@@ -1,3 +1,9 @@
+/*
+ * This file is part of vimix - video live mixer
+ * https://github.com/brunoherbelin/vimix
+ * (C) 2019-2022 Bruno Herbelin <bruno.herbelin@gmail.com>
+ * Distributed under GNU GPL3+ License
+**/
 uniform float Red;
 uniform float Green;
 uniform float Blue;
diff --git a/rsc/shaders/filters/contour_2.glsl b/rsc/shaders/filters/contour_2.glsl
index 44a91e4..7130655 100644
--- a/rsc/shaders/filters/contour_2.glsl
+++ b/rsc/shaders/filters/contour_2.glsl
@@ -1,3 +1,9 @@
+/*
+ * This file is part of vimix - video live mixer
+ * https://github.com/brunoherbelin/vimix
+ * (C) 2019-2022 Bruno Herbelin <bruno.herbelin@gmail.com>
+ * Distributed under GNU GPL3+ License
+**/
 uniform float Amount;
 
 #define N 7
diff --git a/rsc/shaders/filters/dilation.glsl b/rsc/shaders/filters/dilation.glsl
index 537dd22..e8eb371 100644
--- a/rsc/shaders/filters/dilation.glsl
+++ b/rsc/shaders/filters/dilation.glsl
@@ -1,3 +1,9 @@
+/*
+ * This file is part of vimix - video live mixer
+ * https://github.com/brunoherbelin/vimix
+ * (C) 2019-2022 Bruno Herbelin <bruno.herbelin@gmail.com>
+ * Distributed under GNU GPL3+ License
+**/
 uniform float Radius;
 #define MAX_SIZE 5
 
diff --git a/rsc/shaders/filters/dithering.glsl b/rsc/shaders/filters/dithering.glsl
index b4f8734..5b32bb5 100644
--- a/rsc/shaders/filters/dithering.glsl
+++ b/rsc/shaders/filters/dithering.glsl
@@ -1,3 +1,6 @@
+// Ordered Dithering Shader https://www.shadertoy.com/view/4lSSRR
+// by mooglemoogle
+// Adapted by Bruno Herbelin for vimix
 float Factor = 0.5;
 
 const float mult = 1.0 / 17.0;
diff --git a/rsc/shaders/filters/earlybird.glsl b/rsc/shaders/filters/earlybird.glsl
new file mode 100644
index 0000000..6ff4735
--- /dev/null
+++ b/rsc/shaders/filters/earlybird.glsl
@@ -0,0 +1,85 @@
+/** 
+ * Earlybird Filter by Ruofei Du (DuRuofei.com)
+ * Demo: https://www.shadertoy.com/view/4lSyDK
+ * starea @ ShaderToy,License Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License.
+ * https://creativecommons.org/licenses/by-nc-sa/3.0/
+ * 
+ * Reference: 
+ * [1] colorBurn function forked from ben's https://www.shadertoy.com/view/XdS3RW
+ * [2] starea's Dotted Drawing / Sketch Effect: https://www.shadertoy.com/view/ldSyzV
+ * [3] starea's BrightnessContrastSaturationHue: https://www.shadertoy.com/view/MdjBRy
+ *
+ * Series:
+ * [1] Brannan Filter: https://www.shadertoy.com/view/4lSyDK
+ * [2] Earlybird Filter: https://www.shadertoy.com/view/XlSyWV
+ * [3] Starea Filter: https://www.shadertoy.com/view/MtjyDK
+ * 
+ *
+ * Write-ups:
+ * [1] http://blog.ruofeidu.com/implementing-instagram-filters-brannan/
+ **/
+float greyScale(in vec3 col) 
+{
+    return dot(col, vec3(0.3, 0.59, 0.11));
+}
+
+mat3 saturationMatrix( float saturation ) {
+    vec3 luminance = vec3( 0.3086, 0.6094, 0.0820 );
+    float oneMinusSat = 1.0 - saturation;
+    vec3 red = vec3( luminance.x * oneMinusSat );
+    red.r += saturation;
+    
+    vec3 green = vec3( luminance.y * oneMinusSat );
+    green.g += saturation;
+    
+    vec3 blue = vec3( luminance.z * oneMinusSat );
+    blue.b += saturation;
+    
+    return mat3(red, green, blue);
+}
+
+void levels(inout vec3 col, in vec3 inleft, in vec3 inright, in vec3 outleft, in vec3 outright) {
+    col = clamp(col, inleft, inright);
+    col = (col - inleft) / (inright - inleft);
+    col = outleft + col * (outright - outleft);
+}
+
+void brightnessAdjust( inout vec3 color, in float b) {
+    color += b;
+}
+
+void contrastAdjust( inout vec3 color, in float c) {
+    float t = 0.5 - c * 0.5; 
+    color = color * c + t;
+}
+
+
+vec3 colorBurn(in vec3 s, in vec3 d )
+{
+	return 1.0 - (1.0 - d) / s;
+}
+
+void mainImage( out vec4 fragColor, in vec2 fragCoord )
+{
+	vec2 uv = fragCoord.xy / iResolution.xy;
+    vec3 col = texture(iChannel0, uv).rgb; 
+    vec2 coord = ( fragCoord.xy + fragCoord.xy -  iResolution.xy ) / iResolution.y;
+    vec3 gradient = vec3(pow(1.0 - length(coord * 0.4), 0.6) * 1.2); 
+    vec3 grey = vec3(184./255.);
+    vec3 tint = vec3(252., 243., 213.) / 255.;
+    col = saturationMatrix(0.68) * col; 
+    levels(col, vec3(0.), vec3(1.0), 
+                vec3(27.,0.,0.) / 255., vec3(255.) / 255.); 
+    col = pow(col, vec3(1.19));
+    brightnessAdjust(col, 0.13); 
+    contrastAdjust(col, 1.05); 
+    col = saturationMatrix(0.85) * col; 
+    levels(col, vec3(0.), vec3(235./255.), 
+                vec3(0.,0.,0.) / 255., vec3(255.) / 255.); 
+    
+    col = mix(tint * col, col, gradient); 
+    col = colorBurn(grey, col); 
+    //col *= 0.8;
+    fragColor = vec4(col, 1.0);
+}
+
diff --git a/rsc/shaders/filters/edge.glsl b/rsc/shaders/filters/edge.glsl
index 44efb7c..6a3503a 100644
--- a/rsc/shaders/filters/edge.glsl
+++ b/rsc/shaders/filters/edge.glsl
@@ -1,3 +1,9 @@
+/*
+ * This file is part of vimix - video live mixer
+ * https://github.com/brunoherbelin/vimix
+ * (C) 2019-2022 Bruno Herbelin <bruno.herbelin@gmail.com>
+ * Distributed under GNU GPL3+ License
+**/
 
 uniform float Threshold;
 
diff --git a/rsc/shaders/filters/erosion.glsl b/rsc/shaders/filters/erosion.glsl
index fe42629..b1c11c7 100644
--- a/rsc/shaders/filters/erosion.glsl
+++ b/rsc/shaders/filters/erosion.glsl
@@ -1,3 +1,9 @@
+/*
+ * This file is part of vimix - video live mixer
+ * https://github.com/brunoherbelin/vimix
+ * (C) 2019-2022 Bruno Herbelin <bruno.herbelin@gmail.com>
+ * Distributed under GNU GPL3+ License
+**/
 uniform float Radius;
 #define MAX_SIZE 5
 
diff --git a/rsc/shaders/filters/focus.glsl b/rsc/shaders/filters/focus.glsl
index 5368037..13c82a1 100644
--- a/rsc/shaders/filters/focus.glsl
+++ b/rsc/shaders/filters/focus.glsl
@@ -1,11 +1,10 @@
-//  Bilateral filter
-// (c) mrharicot https://www.shadertoy.com/view/4dfGDH
+// Bilateral filter
+// inspired from mrharicot https://www.shadertoy.com/view/4dfGDH
 
 #define SIGMA 10.0
+#define BSIGMA 0.1
 #define MSIZE 13
 
-uniform float Factor;
-
 float normpdf(in float x, in float sigma)
 {
     return 0.39894*exp(-0.5*x*x/(sigma*sigma))/sigma;
@@ -18,34 +17,29 @@ float normpdf3(in vec4 v, in float sigma)
 
 void mainImage( out vec4 fragColor, in vec2 fragCoord )
 {
-    vec4 c = texture(iChannel0, (fragCoord.xy / iResolution.xy) );
-
     const int kSize = (MSIZE-1)/2;
     float kernel[MSIZE];
-    vec4 final_colour = vec4(0.0);
+    vec4 O = vec4(0.0);
 
     //create the 1-D kernel
     float Z = 0.0;
     for (int j = 0; j <= kSize; ++j)
-    {
         kernel[kSize+j] = kernel[kSize-j] = normpdf(float(j), SIGMA);
-    }
 
     vec4 cc;
-    float fac;
-    float bsigma = mix(0.01, 1.2, Factor);
-    float bZ = 1.0/normpdf(0.0, bsigma);
+    vec4 c = texture(iChannel0, (fragCoord.xy / iResolution.xy) );
+    float bZ = 1.0/normpdf(0.0, BSIGMA);
     for (int i=-kSize; i <= kSize; ++i)
     {
         for (int j=-kSize; j <= kSize; ++j)
         {
-            cc = texture(iChannel0, (fragCoord.xy+vec2(float(i),float(j))) / iResolution.xy);
-            fac = normpdf3(cc-c, bsigma)*bZ*kernel[kSize+j]*kernel[kSize+i];
+            cc = texture(iChannel0, (fragCoord+vec2(float(i),float(j))) / iResolution.xy);
+            float fac = normpdf3(cc-c, BSIGMA)*bZ*kernel[kSize+j]*kernel[kSize+i];
             Z += fac;
-            final_colour += fac*cc;
+            O += fac*cc;
         }
     }
 
-    fragColor = final_colour/Z;
+    fragColor = O/Z;
 }
 
diff --git a/rsc/shaders/filters/freichen.glsl b/rsc/shaders/filters/freichen.glsl
index 9017f88..5ab297a 100644
--- a/rsc/shaders/filters/freichen.glsl
+++ b/rsc/shaders/filters/freichen.glsl
@@ -1,3 +1,9 @@
+/*
+ * This file is part of vimix - video live mixer
+ * https://github.com/brunoherbelin/vimix
+ * (C) 2019-2022 Bruno Herbelin <bruno.herbelin@gmail.com>
+ * Distributed under GNU GPL3+ License
+**/
 uniform float Factor;
 
 const mat3 G[9] = mat3[](
diff --git a/rsc/shaders/filters/hasheddilation.glsl b/rsc/shaders/filters/hasheddilation.glsl
index a432813..d594bc8 100644
--- a/rsc/shaders/filters/hasheddilation.glsl
+++ b/rsc/shaders/filters/hasheddilation.glsl
@@ -1,11 +1,13 @@
+/*
+ * This file is part of vimix - video live mixer
+ * https://github.com/brunoherbelin/vimix
+ * (C) 2019-2022 Bruno Herbelin <bruno.herbelin@gmail.com>
+ * Distributed under GNU GPL3+ License
+**/
 #define TWOPI 6.28318530718
 
 uniform float Radius;
 
-// float hash(vec2 co){
-//     return fract(sin(dot(co.xy, vec2(12.9898,78.233))) * 43758.5453);
-// }
-
 #define SEED uvec4(0x5C995C6Du, 0x6A3C6A57u, 0xC65536CBu, 0x3563995Fu)
 const uint lcgM = 2891336453u;// ideal for 32 bits with odd c
 uint  asuint2(float x) { return x == 0.0 ? 0u : floatBitsToUint(x); }
diff --git a/rsc/shaders/filters/hashederosion.glsl b/rsc/shaders/filters/hashederosion.glsl
index f558e62..26884ee 100644
--- a/rsc/shaders/filters/hashederosion.glsl
+++ b/rsc/shaders/filters/hashederosion.glsl
@@ -1,3 +1,9 @@
+/*
+ * This file is part of vimix - video live mixer
+ * https://github.com/brunoherbelin/vimix
+ * (C) 2019-2022 Bruno Herbelin <bruno.herbelin@gmail.com>
+ * Distributed under GNU GPL3+ License
+**/
 #define TWOPI 6.28318530718
 
 uniform float Radius;
diff --git a/rsc/shaders/filters/kuwahara.glsl b/rsc/shaders/filters/kuwahara.glsl
index 6427dec..0da0cc7 100644
--- a/rsc/shaders/filters/kuwahara.glsl
+++ b/rsc/shaders/filters/kuwahara.glsl
@@ -5,6 +5,7 @@
 // This shader is modified to be compatible with LOVE2D's quirky shader engine!
 // Modified by Christian D. Madsen
 // https://github.com/strangewarp/LoveAnisotropicKuwahara
+// Adapted by Bruno Herbelin for vimix
 
 uniform float Radius;
 
diff --git a/rsc/shaders/filters/lumakey.glsl b/rsc/shaders/filters/lumakey.glsl
index edca9d0..ba5e42d 100644
--- a/rsc/shaders/filters/lumakey.glsl
+++ b/rsc/shaders/filters/lumakey.glsl
@@ -1,3 +1,9 @@
+/*
+ * This file is part of vimix - video live mixer
+ * https://github.com/brunoherbelin/vimix
+ * (C) 2019-2022 Bruno Herbelin <bruno.herbelin@gmail.com>
+ * Distributed under GNU GPL3+ License
+**/
 uniform float Threshold;
 uniform float Tolerance;
 
diff --git a/rsc/shaders/filters/pixelate.glsl b/rsc/shaders/filters/pixelate.glsl
index 44da75e..c3f9998 100644
--- a/rsc/shaders/filters/pixelate.glsl
+++ b/rsc/shaders/filters/pixelate.glsl
@@ -1,20 +1,23 @@
+// simple RGBA pixelation with averaging
+// by Bruno Herbelin
+
 float Size = 0.5;
-float Sharpen = 0.5;
+float Sharpen = 0.9;
 
 const mat3 G = mat3( 0.0625, 0.125, 0.0625, 0.125, 0.25, 0.125, 0.0625, 0.125, 0.0625);
-        
+
 void mainImage( out vec4 fragColor, in vec2 fragCoord ) {
 
     vec2 size = vec2(3.0 * iResolution.x / iResolution.y, 3.0 );
     size =  mix( size, iResolution.xy, pow(1.0 - Size, 3.0) ) ;
     vec2 vUv = size / iResolution.xy;
 
-    vec3 blur = vec3(0,0,0);
+    vec4 blur = vec4(0);
     for (int i=0; i<3; i++)
         for (int j=0; j<3; j++) {
-            blur += G[i][j] * texture(iChannel0, round( (vUv * fragCoord) + vec2(i-1,j-1) ) / size ).rgb;
+            blur += G[i][j] * texture(iChannel0, round( (vUv * fragCoord) + vec2(i-1,j-1) ) / size );
         }
 
-    fragColor = vec4( mix( blur, texture(iChannel0, round(vUv * fragCoord) / size ).rgb, Sharpen), 1.0);
+    fragColor = mix( blur, texture(iChannel0, round(vUv * fragCoord) / size ), Sharpen);
 }
 
diff --git a/rsc/shaders/filters/resample_double.glsl b/rsc/shaders/filters/resample_double.glsl
index 7cdbd43..106d97c 100644
--- a/rsc/shaders/filters/resample_double.glsl
+++ b/rsc/shaders/filters/resample_double.glsl
@@ -1,3 +1,9 @@
+/*
+ * This file is part of vimix - video live mixer
+ * https://github.com/brunoherbelin/vimix
+ * (C) 2019-2022 Bruno Herbelin <bruno.herbelin@gmail.com>
+ * Distributed under GNU GPL3+ License
+**/
 //=======================================================================================
 vec4 CubicHermite (vec4 A, vec4 B, vec4 C, vec4 D, float t)
 {
diff --git a/rsc/shaders/filters/resample_half.glsl b/rsc/shaders/filters/resample_half.glsl
index 76a6b27..f7d58e2 100644
--- a/rsc/shaders/filters/resample_half.glsl
+++ b/rsc/shaders/filters/resample_half.glsl
@@ -1,3 +1,9 @@
+/*
+ * This file is part of vimix - video live mixer
+ * https://github.com/brunoherbelin/vimix
+ * (C) 2019-2022 Bruno Herbelin <bruno.herbelin@gmail.com>
+ * Distributed under GNU GPL3+ License
+**/
 // inspired by https://www.shadertoy.com/view/fsjBWm (License: MIT)
 
 void mainImage( out vec4 fragColor, in vec2 fragCoord )
diff --git a/rsc/shaders/filters/sharp.glsl b/rsc/shaders/filters/sharp.glsl
index bd9bb64..e334228 100644
--- a/rsc/shaders/filters/sharp.glsl
+++ b/rsc/shaders/filters/sharp.glsl
@@ -1,4 +1,10 @@
-uniform float Amount; 
+/*
+ * This file is part of vimix - video live mixer
+ * https://github.com/brunoherbelin/vimix
+ * (C) 2019-2022 Bruno Herbelin <bruno.herbelin@gmail.com>
+ * Distributed under GNU GPL3+ License
+**/
+uniform float Amount;
 
 vec4 sharp(sampler2D sampler, vec2 fc, vec2 re)
 {
diff --git a/rsc/shaders/filters/sharpen.glsl b/rsc/shaders/filters/sharpen.glsl
index 0d56d6d..092bdb4 100644
--- a/rsc/shaders/filters/sharpen.glsl
+++ b/rsc/shaders/filters/sharpen.glsl
@@ -1,3 +1,9 @@
+/*
+ * This file is part of vimix - video live mixer
+ * https://github.com/brunoherbelin/vimix
+ * (C) 2019-2022 Bruno Herbelin <bruno.herbelin@gmail.com>
+ * Distributed under GNU GPL3+ License
+**/
 uniform float Amount;
 
 vec4 texSample(const int x, const int y, in vec2 fragCoord)
diff --git a/rsc/shaders/filters/sharpen_1.glsl b/rsc/shaders/filters/sharpen_1.glsl
index c4ef3ac..677250a 100644
--- a/rsc/shaders/filters/sharpen_1.glsl
+++ b/rsc/shaders/filters/sharpen_1.glsl
@@ -1,3 +1,9 @@
+/*
+ * This file is part of vimix - video live mixer
+ * https://github.com/brunoherbelin/vimix
+ * (C) 2019-2022 Bruno Herbelin <bruno.herbelin@gmail.com>
+ * Distributed under GNU GPL3+ License
+**/
 uniform float Amount;
 
 #define N 7
diff --git a/rsc/shaders/filters/sharpen_2.glsl b/rsc/shaders/filters/sharpen_2.glsl
index 9b8990b..9544dba 100644
--- a/rsc/shaders/filters/sharpen_2.glsl
+++ b/rsc/shaders/filters/sharpen_2.glsl
@@ -1,3 +1,9 @@
+/*
+ * This file is part of vimix - video live mixer
+ * https://github.com/brunoherbelin/vimix
+ * (C) 2019-2022 Bruno Herbelin <bruno.herbelin@gmail.com>
+ * Distributed under GNU GPL3+ License
+**/
 uniform float Amount;
 
 #define N 7
diff --git a/rsc/shaders/filters/sharpenedge.glsl b/rsc/shaders/filters/sharpenedge.glsl
index c3efff7..f2dd790 100644
--- a/rsc/shaders/filters/sharpenedge.glsl
+++ b/rsc/shaders/filters/sharpenedge.glsl
@@ -1,3 +1,9 @@
+/*
+ * This file is part of vimix - video live mixer
+ * https://github.com/brunoherbelin/vimix
+ * (C) 2019-2022 Bruno Herbelin <bruno.herbelin@gmail.com>
+ * Distributed under GNU GPL3+ License
+**/
 uniform float Amount;
 
 vec3 blurSample(in vec2 uv, in vec2 xoff, in vec2 yoff)
diff --git a/rsc/shaders/filters/sigmoid_1.glsl b/rsc/shaders/filters/sigmoid_1.glsl
index 0fbd96a..d18e834 100644
--- a/rsc/shaders/filters/sigmoid_1.glsl
+++ b/rsc/shaders/filters/sigmoid_1.glsl
@@ -1,3 +1,9 @@
+/*
+ * This file is part of vimix - video live mixer
+ * https://github.com/brunoherbelin/vimix
+ * (C) 2019-2022 Bruno Herbelin <bruno.herbelin@gmail.com>
+ * Distributed under GNU GPL3+ License
+**/
 #define RADIUS 0.2
 
 uniform float Amount;
diff --git a/rsc/shaders/filters/sigmoid_2.glsl b/rsc/shaders/filters/sigmoid_2.glsl
index dcb228a..85c7c53 100644
--- a/rsc/shaders/filters/sigmoid_2.glsl
+++ b/rsc/shaders/filters/sigmoid_2.glsl
@@ -1,3 +1,9 @@
+/*
+ * This file is part of vimix - video live mixer
+ * https://github.com/brunoherbelin/vimix
+ * (C) 2019-2022 Bruno Herbelin <bruno.herbelin@gmail.com>
+ * Distributed under GNU GPL3+ License
+**/
 #define RADIUS 0.2
 
 uniform float Amount;
diff --git a/rsc/shaders/filters/sketch.glsl b/rsc/shaders/filters/sketch.glsl
index 61901ab..2b34415 100644
--- a/rsc/shaders/filters/sketch.glsl
+++ b/rsc/shaders/filters/sketch.glsl
@@ -1,4 +1,3 @@
-
 /** 
  * Sketchy Stippling / Dot-Drawing Effect by Ruofei Du (DuRuofei.com)
  * Link to demo: https://www.shadertoy.com/view/ldSyzV
diff --git a/rsc/shaders/filters/sobel.glsl b/rsc/shaders/filters/sobel.glsl
index 0bec9c6..30e7c45 100644
--- a/rsc/shaders/filters/sobel.glsl
+++ b/rsc/shaders/filters/sobel.glsl
@@ -1,3 +1,9 @@
+/*
+ * This file is part of vimix - video live mixer
+ * https://github.com/brunoherbelin/vimix
+ * (C) 2019-2022 Bruno Herbelin <bruno.herbelin@gmail.com>
+ * Distributed under GNU GPL3+ License
+**/
 uniform float  Factor;
 
 const mat3 G[2] = mat3[](
diff --git a/rsc/shaders/filters/stippling.glsl b/rsc/shaders/filters/stippling.glsl
index fd242a6..e517887 100644
--- a/rsc/shaders/filters/stippling.glsl
+++ b/rsc/shaders/filters/stippling.glsl
@@ -1,53 +1,53 @@
-float Factor = 0.3;
+// Blue Noise Stippling 2 https://www.shadertoy.com/view/ldyXDd by FabriceNeyret2
+// simplified version of joeedh's https://www.shadertoy.com/view/Md3GWf
+// see also https://www.shadertoy.com/view/MdtGD7
+// --- checkerboard noise : to decorelate the pattern between size x size tiles
+// Adapted by Bruno Herbelin for vimix
 
-#define SEED1 -0.5775604999999985
-#define SEED2 6.440483302499992
+// simple x-y decorrelated noise seems enough
+#define stepnoise0(p, size) rnd( floor(p/size)*size )
+#define rnd(U) fract(sin( 1e3*(U)*mat2(1,-7.131, 12.9898, 1.233) )* 43758.5453)
 
+//   joeedh's original noise (cleaned-up)
 vec2 stepnoise(vec2 p, float size) {
-    p += 10.0;
-    float x = floor(p.x/size)*size;
-    float y = floor(p.y/size)*size;
-
-    x = fract(x*0.1) + 1.0 + x*0.0002;
-    y = fract(y*0.1) + 1.0 + y*0.0003;
-
-    float a = fract(1.0 / (0.000001*x*y + 0.00001));
-    a = fract(1.0 / (0.000001234*a + 0.00001));
-
-    float b = fract(1.0 / (0.000002*(x*y+x) + 0.00001));
-    b = fract(1.0 / (0.0000235*b + 0.00001));
-
-    return vec2(a, b);
-}
-
-float tent(float f) {
-    return 1.0 - abs(fract(f)-0.5)*2.0;
+    p = floor((p+10.)/size)*size;          // is p+10. useful ?
+    p = fract(p*.1) + 1. + p*vec2(2,3)/1e4;
+    p = fract( 1e5 / (.1*p.x*(p.y+vec2(0,1)) + 1.) );
+    p = fract( 1e5 / (p*vec2(.1234,2.35) + 1.) );
+    return p;
 }
 
+// --- stippling mask  : regular stippling + per-tile random offset + tone-mapping
 float mask(vec2 p) {
-    vec2 r = stepnoise(p, 8.423424);
-    p[0] += r[0];
-    p[1] += r[1];
+#define SEED1 1.705
+#define DMUL  8.12235325       // are exact DMUL and -.5 important ?
+    p += ( stepnoise0(p, 5.5) - .5 ) *DMUL;   // bias [-2,2] per tile otherwise too regular
+    float f = fract( p.x*SEED1 + p.y/(SEED1+.15555) ); //  weights: 1.705 , 0.5375
+  //return f;  // If you want to skeep the tone mapping
+    f *= 1.03; //  to avoid zero-stipple in plain white ?
+    // --- indeed, is a tone mapping ( equivalent to do the reciprocal on the image, see tests )
+    // returned value in [0,37.2] , but < 0.57 with P=50%
+    return  (pow(f, 150.) + 1.3*f ) / 2.3; // <.98 : ~ f/2, P=50%  >.98 : ~f^150, P=50%
+}                                          // max = 37.2, int = 0.55
 
-    float f1 = tent(p[0]*SEED1 + p[1]/(SEED1+0.5));
-    float f2 = tent(p[1]*SEED2 + p[0]/(SEED2+0.5));
-    float f = sqrt( f1*f2 );
+// --- for ramp at screen bottom
+#define tent(f) ( 1. - abs(2.*fract(f)-1.) )
+// --- fetch luminance( texture (pixel + offset) )
+#define s(x,y) dot( texture(iChannel0, (U+vec2(x,y))/R ), vec4(.3,.6,.1,0) ) // luminance
 
-    return f;
-}
-
-float saturation(vec3 color) {
-    return (min(color.r, min(color.g, color.b)) + max(color.r, max(color.g, color.b))) * 0.5;
-}
-
-void mainImage( out vec4 fragColor, in vec2 fragCoord )
+void mainImage( out vec4 O, vec2 U )
 {
-    vec2 uv = fragCoord.xy;
-    vec2 uv2 = fragCoord.xy / iResolution.x;
+    vec2 R = iResolution.xy; O-=O;
+    // --- fetch video luminance and enhance the contrast
+    float f =  s(-1,-1) + s(-1,0) + s(-1,1)
+             + s( 0,-1) +         + s( 0,1)
+             + s( 1,-1) + s( 1,0) + s( 1,1),
+         f0 = s(0,0);
+    f = ( .125*f + 8.*f0 ) / 6.;
 
-    float f = saturation( texture(iChannel0, fragCoord.xy / iResolution.xy).rgb );
-    float c = mask(uv);
-    c = float( f > mix( 0.6 * c, 1.4 * c, Factor) );
+    f = f0 - ( f-f0 ) * 0.5;
 
-    fragColor = vec4(c, c, c, texture(iChannel0, fragCoord.xy / iResolution.xy).a );
+    // --- stippling
+    O += step(mask(U), f);
 }
+
diff --git a/rsc/shaders/filters/tophat.glsl b/rsc/shaders/filters/tophat.glsl
index 0891801..ef8365d 100644
--- a/rsc/shaders/filters/tophat.glsl
+++ b/rsc/shaders/filters/tophat.glsl
@@ -1,3 +1,9 @@
+/*
+ * This file is part of vimix - video live mixer
+ * https://github.com/brunoherbelin/vimix
+ * (C) 2019-2022 Bruno Herbelin <bruno.herbelin@gmail.com>
+ * Distributed under GNU GPL3+ License
+**/
 uniform float Radius;
 #define MAX_SIZE 5