W3C home > Mailing lists > Public > public-audio@w3.org > July to September 2013

Re: [web-audio-api] (OscillatorTypes): Oscillator types are not defined (#104)

From: Olivier Thereaux <notifications@github.com>
Date: Wed, 11 Sep 2013 07:29:35 -0700
To: WebAudio/web-audio-api <web-audio-api@noreply.github.com>
Message-ID: <WebAudio/web-audio-api/issues/104/24244238@github.com>
> [Original comment](https://www.w3.org/Bugs/Public/show_bug.cgi?id=17366#3) by Marcus Geelnard (Opera) on W3C Bugzilla. Mon, 02 Sep 2013 07:40:27 GMT

Paul, I think that specifying the amplitude (i.e. time-domain signal) the way you suggest requires that an implementation does not deal with frequency folding.

An important point of the oscillator node is that it is capable of producing a high quality signal without folding effects. For instance, this requires that the signal is allowed to have ripples (for every wave type except the sine).

I agree that we need to specify:

- The phase of the signal (and it should be consistent between wave forms).
- The signal strength (RMS, or something else).

On the other hand, I'm not sure how to specify the actual time-domain amplitude level. As I've mentioned before, there are a wide range of options for implementing the signal generation logic.

One option could be to specify the signal amplitude as a continuous time signal (i.e. with infinite sample rate), and then specify in what ways an implementation is allowed to sample this continuous time signal.

Also, I think that we should decide whether or not it's OK for implementations to use different signal generation methods (e.g. trade quality for performance), or if all implementations must use a specific signal generation method.

---
Reply to this email directly or view it on GitHub:
https://github.com/WebAudio/web-audio-api/issues/104#issuecomment-24244238
Received on Wednesday, 11 September 2013 14:30:11 UTC

This archive was generated by hypermail 2.4.0 : Friday, 17 January 2020 19:03:24 UTC