# FFT Support in HTML5 non-reduced FMOD?
**URL:** https://qa.fmod.com/t/fft-support-in-html5-non-reduced-fmod/21056
**Category:** FMOD Engine
**Tags:** html5, cpp
**Created:** [January 4, 2024, 12:03am UTC](https://qa.fmod.com/t/fft-support-in-html5-non-reduced-fmod/21056 "2024-01-04T00:03:25Z")
**Posts on this page:** 6
**Page:** 1
### Author:  [@aishi1](https://qa.fmod.com/u/aishi1)
#### Post date: [January 4, 2024, 12:03am UTC](https://qa.fmod.com/t/fft-support-in-html5-non-reduced-fmod/21056/1 "2024-01-04T00:03:26Z")
Hello, I’m making a web app with the HTML5 wasm version of FMOD 2.02.19 and was wondering if FFT DSP is supported in the non-reduced version? Using the logging version, whenever I get the spectrum data, `length` and `numchannels` is always zero, so I thought it might not be supported. I couldn’t find it explicitly stated in the docs, so I just wanted to make sure.
Thank you for your time.
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### Author:  [@aishi1](https://qa.fmod.com/u/aishi1)
#### Post date: [January 5, 2024, 3:04am UTC](https://qa.fmod.com/t/fft-support-in-html5-non-reduced-fmod/21056/2 "2024-01-05T03:04:46Z")
After trying around, I couldn’t get it to work, but I found a workaround using the browser WebAudio API for anyone who might find it useful:
On the JS frontend, you can get the AudioContext from `Module.mContext` and the AudioWorkletNode from which FMOD outputs, from `Module.mWorkletNode` some time after the module initializes. With the AudioContext you can then create an AnalyserNode, then connect the worklet node to it 🙂
I think this might break later on if the API changes though. Accessing the mWorkletNode and mContext breaks into the private implementation.
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### Author:  [@Leah\_FMOD](https://qa.fmod.com/u/Leah_FMOD)
#### Post date: [January 11, 2024, 12:55am UTC](https://qa.fmod.com/t/fft-support-in-html5-non-reduced-fmod/21056/3 "2024-01-11T00:55:11Z")
Hi,
The FFT DSP is supported by both non-reduced and reduced HTML5 versions of FMOD. However, after doing some digging, and the parameters appear to be bugged: while the window size and type parameters are exposed to the API, the spectrum data and dominant frequency parameters are not. I’ve passed this along to the development team for further investigation.
I’m happy to hear you managed to find a workaround in the meantime!
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### Author:  [@aishi1](https://qa.fmod.com/u/aishi1)
#### Post date: [January 11, 2024, 2:06am UTC](https://qa.fmod.com/t/fft-support-in-html5-non-reduced-fmod/21056/4 "2024-01-11T02:06:39Z")
Thanks for looking into the issue, that’s great to hear it’s supported! I was trying to use the length and numchannels to iterate over the spectrum data so I wouldn’t make a bad access. Would it be safe for now to set these parameters even if I can’t read it, or just rely on the default parameters listed in the docs?
As a side question relating to the workaround, it’s nice to be able to access the AudioContext and AudioWorklet - would these possibly ever be exposed in an official way?
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### Author:  [@Leah\_FMOD](https://qa.fmod.com/u/Leah_FMOD)
#### Post date: [January 16, 2024, 3:00am UTC](https://qa.fmod.com/t/fft-support-in-html5-non-reduced-fmod/21056/5 "2024-01-16T03:00:02Z")
> [@aishi1](#):
>
> I was trying to use the length and numchannels to iterate over the spectrum data so I wouldn’t make a bad access. Would it be safe for now to set these parameters even if I can’t read it, or just rely on the default parameters listed in the docs?
Unfortunately [`FMOD_DSP_PARAMETER_FFT`](https://www.fmod.com/docs/2.02/api/plugin-api-dsp.html#fmod_dsp_parameter_fft) cannot be get/set at all at the moment, so attempting to do anything with it/its members or the dominant frequency parameter will do nothing - in that respect, it _should_ be safe.
> [@aishi1](#):
>
> As a side question relating to the workaround, it’s nice to be able to access the AudioContext and AudioWorklet - would these possibly ever be exposed in an official way?
There is precedent with [`System::getOutputHandle`](https://fmod.com/docs/2.02/api/core-api-system.html#system_getoutputhandle), so it’s possible. I’ve added it to our internal feature/improvement tracker.
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### Author:  [@aishi1](https://qa.fmod.com/u/aishi1)
#### Post date: [January 16, 2024, 2:34pm UTC](https://qa.fmod.com/t/fft-support-in-html5-non-reduced-fmod/21056/6 "2024-01-16T14:34:16Z")
I understand, thanks for confirming that. The WebAudio solution is working great, but it would be cool to be able to attach the FFT at any point in the signal chain instead of at the end, like if the user changes the master bus gain for volume control, the signal won’t get diminished. (With web audio, the audio graph points only in one direction, so unless you have ownership of the audio nodes further down the graph you can’t access them.)
That would be interesting to see the `System::getOutputHandle` interface incorporated 🤔
Anyway, thanks again for your helpful answers.