diff --git a/ImageFilter.cpp b/ImageFilter.cpp
index 8afe6c9..f1dcdec 100644
--- a/ImageFilter.cpp
+++ b/ImageFilter.cpp
@@ -215,6 +215,8 @@ ImageFilteringShader::ImageFilteringShader(): ImageShader()
     custom_shading_.setShaders("shaders/image.vs", shader_code_);
 
     timer_ = g_timer_new ();
+    iTime_ = 0.0;
+    iFrame_ = 0;
 
     ImageShader::reset();
 }
@@ -227,7 +229,7 @@ ImageFilteringShader::~ImageFilteringShader()
 
 void ImageFilteringShader::update(float dt)
 {
-    iTime_ += dt;
+    iTime_ += 0.001 * dt;
     if (iTime_ > FLT_MAX)
         iTime_ = 0.0;
 
diff --git a/rsc/shaders/filters/debug.glsl b/rsc/shaders/filters/debug.glsl
new file mode 100644
index 0000000..b051f23
--- /dev/null
+++ b/rsc/shaders/filters/debug.glsl
@@ -0,0 +1,77 @@
+// Created by inigo quilez - iq/2016
+// License Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License.
+
+float udRoundBox( vec2 p, vec2 b, float r )
+{
+  return length(max(abs(p)-b,0.0))-r;
+}
+
+float sdBox( vec2 p, vec2 b )
+{
+  vec2 d = abs(p) - b;
+  return min(max(d.x,d.y),0.0) + length(max(d,0.0));
+}
+
+//-----------------------------------------------------------------
+// Digit drawing function by P_Malin (https://www.shadertoy.com/view/4sf3RN)
+
+float SampleDigit(const in float n, const in vec2 vUV)
+{		
+	if(vUV.x  < 0.0) return 0.0;
+	if(vUV.y  < 0.0) return 0.0;
+	if(vUV.x >= 1.0) return 0.0;
+	if(vUV.y >= 1.0) return 0.0;
+	
+	float data = 0.0;
+	
+	     if(n < 0.5) data = 7.0 + 5.0*16.0 + 5.0*256.0 + 5.0*4096.0 + 7.0*65536.0;
+	else if(n < 1.5) data = 2.0 + 2.0*16.0 + 2.0*256.0 + 2.0*4096.0 + 2.0*65536.0;
+	else if(n < 2.5) data = 7.0 + 1.0*16.0 + 7.0*256.0 + 4.0*4096.0 + 7.0*65536.0;
+	else if(n < 3.5) data = 7.0 + 4.0*16.0 + 7.0*256.0 + 4.0*4096.0 + 7.0*65536.0;
+	else if(n < 4.5) data = 4.0 + 7.0*16.0 + 5.0*256.0 + 1.0*4096.0 + 1.0*65536.0;
+	else if(n < 5.5) data = 7.0 + 4.0*16.0 + 7.0*256.0 + 1.0*4096.0 + 7.0*65536.0;
+	else if(n < 6.5) data = 7.0 + 5.0*16.0 + 7.0*256.0 + 1.0*4096.0 + 7.0*65536.0;
+	else if(n < 7.5) data = 4.0 + 4.0*16.0 + 4.0*256.0 + 4.0*4096.0 + 7.0*65536.0;
+	else if(n < 8.5) data = 7.0 + 5.0*16.0 + 7.0*256.0 + 5.0*4096.0 + 7.0*65536.0;
+	else if(n < 9.5) data = 7.0 + 4.0*16.0 + 7.0*256.0 + 5.0*4096.0 + 7.0*65536.0;
+	
+	vec2 vPixel = floor(vUV * vec2(4.0, 5.0));
+	float fIndex = vPixel.x + (vPixel.y * 4.0);
+	
+	return mod(floor(data / pow(2.0, fIndex)), 2.0);
+}
+
+float PrintInt(const in vec2 uv, const in float value )
+{
+	float res = 0.0;
+	float maxDigits = 1.0+ceil(log2(value)/log2(10.0));
+	float digitID = floor(uv.x);
+	if( digitID>0.0 && digitID<maxDigits )
+	{
+        float digitVa = mod( floor( value/pow(10.0,maxDigits-1.0-digitID) ), 10.0 );
+        res = SampleDigit( digitVa, vec2(fract(uv.x), uv.y) );
+	}
+
+	return res;	
+}
+
+
+void mainImage( out vec4 fragColor, in vec2 fragCoord )
+{
+    float px = 1.0 / iResolution.y;
+    vec2 uv = vec2( fragCoord.x, iResolution.y- fragCoord.y) * px;
+
+    // top: 1.0/iTimeDelta as an integer
+    float col = PrintInt( (uv-vec2(0.2,0.75))*10.0, floor( 1.0/iTimeDelta + 0.5) );
+    
+    // middle; time
+    col += PrintInt( (uv-vec2(0.2,0.5))*10.0, int( iTime * 100) );
+
+    // bottom: frame
+    col += PrintInt( (uv-vec2(0.2,0.25))*10.0, iFrame );
+
+    // iTimeDelta as vertical bar
+    col += (1.0-smoothstep( 0.0, px, sdBox( uv-vec2(0.1,0.0), vec2(0.02,60.0*iTimeDelta) )));
+
+	fragColor = vec4(col,col,col,1.0);
+}