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copied!<p>It's not going to be terribly easy... but here might be a way:</p> <pre><code>var parameters:Array = [1,1,1,1,0.5] var sound:Sound = new Sound(); sound.addEventListener(SampleDataEvent.SAMPLE_DATA, filter); sound.load(soundURLRequest); sound.play(); private function filter(event:SampleDataEvent):void { var freqDomain:Array = FFT(event.data, parameters.length); // You will need to find a FFT(Fast Fourier Transform) function to generate an array. for(var i:int = 0; i < freqDomain.length; i++) { freqDomain[i] = freqDomain[i] * parameters[i]; // This is where your EQ parameters get applied. } var timeDomain:Array = IFFT(freqDomain, event.data.length); // Inverse FFT for(value:Number in timeDomain) { event.data.writeFloat(value); } } </code></pre> <p>Some on the FFT and IFFT functions, FFT usually outputs complex values (real + complex components), which can be converted to magnitude and phase components. What you really need is only the magnitude, which has a formula = (sqrt(real^2 + complex^2)). Humans ears are NOT sensitive to the phase (As opposed to the eyes, which are VERY sensitive to phase), so when you do the inverse FFT, you can insert a random or flat phase with little difference. Note that my approach is very low level in terms of filter implementation.</p> <p>Here is a Fourier Transform function (not Fast though, it's just a convolution (O(n^2)) vs FFT O(nlogn)) just for reference (err.. it's off the top of my head so if might be wrong with the constants):</p> <pre><code>// Note that this only returns the magnitude, I am discarding the phase. function FFT(sample:Array, size):Array { var frequencies = new Array(size); for(int i = 0; i < sample.size; i++) { for(int j = 0; i < frequencies.size; j++) { var real:Number = sample[i] * Math.cos(Math.PI/2 * i * j); var complex:Number = sample[i] * Math.sin(Math.PI/2 * i * j); frequencies[j] += Math.sqrt(real * real + complex * complex); } } return frequencies; } </code></pre>

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