help with float number output from a shader

[Alexar]

hi all, i wanted to use shader to create a data sheet for a sample of a audio source. well, during input and output the data, there are some difficulties.

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self.audio = love.graphics.newCanvas(self.rate,1,"r32f",0)

to create float datasheet with a single channel.

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vec4 effect( vec4 color, sampler2D tex, vec2 tc,vec2 sc) {
    float t = sc.x;
    float y = sin(6000*t)*exp(-2*t);
    return vec4(y,0,0,0);
}

in shader we output the r channel for the datasheet. draw thing with the shader to the canvas, so that we get a canvas filled the proper data.

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local data = self.audio:newImageData()
    for i ,d in ipairs(self.data) do
        print(data:getPixel(i-1,0))
    end

and for output the data. all the data in imagedata generated are converted to r,g,b,a int8[4]. but how to receive the data that we need?
thank you fot the help.

[grump]

Canvas:newImageData() always creates an RGBA image with 8 bit integer channels. That makes it impossible to read back raw float values through an ImageData object, and as far as I know LÖVE does not provide any other way to retrieve the values.

[Alexar]

solved by using love0.11 which uses normalized floats as color data.