[ANSWERED] GLSL BLUR Shader

gapworks

I found a code which i want to use in upcoming project but I'm not familiar with shaders at all. i added the code as a text file and a screenshot.

my main problem is that the amount of blur is to little and i can turn it on of off via bypass. i would need a slider ( at the end controlled via a dmx channel) for the amount and i don't need all the moose options.

Any help is highly appreciated. It's quite urgent. the reason why i don't use the Isadora blur actor is that it drops the performance a lot. whyever.

DusX

@gapworks I took a stab at it, but I dont' have much glsl experience... and I got stuck trying to dynamically set mSize.
It seems to want a Const to define an array.

So, do you need smooth translation of the blur?
You could have a few copies of the GLSL, where you set 'const int mSize = ??;' to different amounts, say, 10, 20, 30, 40 or what ever, and use a Router to switch the feed between them, allowing some control over the level?

regarding the extra parameters, you can hid them easily enough (setting them to zero, appears to setup the GLSL to affect the whole image), by right clicking the actor and selecting Show/Hide Properties.. and hiding the options you don't need.

bonemap

@gapworks

Hi,

Here is a modification of your GLSL code that might be useful:

// ISADORA_FLOAT_PARAM(blurA, inti, .1, 10, .1, "No help available.")
uniform float blurA;
#ifdef GL_ES
precision mediump float;
#endif
float normpdf(in float x, in float blurA)
{
return 0.39894*exp(-0.01*x*x/(blurA*blurA))/blurA;
}
void mainImage( out vec4 fragColor, in vec2 fragCoord )
{
vec3 c = texture(iChannel0, fragCoord.xy / iResolution.xy).rgb;
//if (fragCoord.x < iMouse.x)
//{
//fragColor = vec4(c, 1.0);
//} else 
{
//declare stuff
const int mSize = 11;
const int kSize = (mSize-1)/2;
float kernel[mSize];
vec3 final_colour = vec3(0.0);
//create the 1-D kernel
float sigma = blurA;
float Z = 0.0;
for (int j = 0; j <= kSize; ++j)
{
kernel[kSize+j] = kernel[kSize-j] = normpdf(float(j), sigma);
}
//get the normalization factor (as the gaussian has been clamped)
for (int j = 0; j < mSize; ++j)
{
Z += kernel[j];
}
//read out the texels
for (int i=-kSize; i <= kSize; ++i)
{
for (int j=-kSize; j <= kSize; ++j)
{
final_colour += kernel[kSize+j]*kernel[kSize+i]*texture(iChannel0, (fragCoord.xy+vec2(float(i),float(j))) / iResolution.xy).rgb;
}
}
fragColor = vec4(final_colour/(Z*Z), 1.0);
}
}

gapworks

@bonemap

thanks both of u for ur support. the one thing left ist the blur amount which is to little. how and where can i change this

bonemap

@gapworks

hi,

I did have a look at the blur amount, but it was not possible to increase that without the shader over heating.

I tried a couple of things, including daisy-chaining three or four instances of the actor - that is worth a try. However, the pre-loaded Gaussian Blur actor that comes as a standard actor in Isadora might be a viable option?

Best wishes

Russell

bonemap

@gapworks

I had another thought about it because I did notice that the resolution of the shader affects the amount of blur apparent in the image. So I made this user actor that scales the shader resolution as it applies the blur effectively increasing the appearance of blur across the image:

blurry.iua3

DusX

@gapworks

I have attached a 2 GLSL shader based approach. Its fast and from my initial tests looks pretty good.
It does a horizontal blur, followed by a vertical blur.

glsl_blur.izz

bonemap

@dusx said:

I have attached a 2 GLSL shader based approach. Its fast and from my initial tests looks pretty good. It does a horizontal blur, followed by a vertical blur.

Hi,

This works great!

Beat Wishes

Russell

gapworks

@dusx

Brilliant! Thank all of you so much

Woland

@dusx said:

I have attached a 2 GLSL shader based approach. Its fast and from my initial tests looks pretty good. It does a horizontal blur, followed by a vertical blur.

It'd be great if you could upload these to the Add-Ons Page (if you haven't already).

Best wishes,

Woland

gapworks

@woland

i , thanx to the help of all of you i managed to finalise my eos fixture and the corresponding izzy patch. works like charm. than again.izzyeos.zipin the zip file you will find the patch, the eos fixture file and the blur qua

best

peter