Clarify influence/reference to OpenAL, IPR considerations

[olivierthereaux]

Originally reported on W3C Bugzilla ISSUE-22969 Thu, 15 Aug 2013 08:39:43 GMT
Reported by Olivier Thereaux
Assigned to

The Web Audio API makes several references (mostly in informational text) about OpenAL and the spec editor has often mentioned it as one of the inspirations for the architecture of the API.

OpenAL was “ done in spirit of open source and implementations distributed in LGPL“ but the licensing/IPR is not clear - and most of the people involved with OpenAL have since moved on.

The Audio WG should review the current spec and assess whether:

• Whether the web audio API is significantly inspired by Open AL
• Whether OpenAL should be formally referred to in the specification
• Depending on the above, whether there are any IPR concerns in the architectural lineage between OpenAL and WebAudioAPI

[olivierthereaux]

Original comment by Olivier Thereaux on W3C Bugzilla. Tue, 27 Aug 2013 10:25:50 GMT

With the help of the W3C Legal counsel, I have done an analysis of the situation based on a recent version of OpenAL-soft (open source fork of OpenAL - OpenAL itself seems to be completely AWOL).

The four parts of the web audio API where OpenAL is mentioned are:

(in 4.15. The AudioListener Interface)

// same as OpenAL (default 1)
attribute float dopplerFactor;

My analysis: the name dopplerFactor is indeed the same as in the OpenAL library. That said, Doppler Factor is a well-known mathematical variable, and I don't think that there is significant IP or indeed any copyright concern in naming a variable after the mathematical variable it represents. I would remove the "same as OpenAL" which seems to be neither useful nor necessary.

(in 11. Spatialization / Panning)

A common feature requirement for modern 3D games is the ability to dynamically spatialize and move multiple audio sources in 3D space. Game audio engines such as OpenAL, FMOD, Creative's EAX, Microsoft's XACT Audio, etc. have this ability.

My analysis: I don't know if this section is useful, but it is a non-issue as far as IPR/copyright is concerned.

(in 12. Linear Effects using Convolution)

A key feature of many game audio engines (OpenAL, FMOD, Creative's EAX, Microsoft's XACT Audio, etc.) is a reverberation effect for simulating the sound of being in an acoustic space.

Ditto above.

(In Changelog)

date: Mon Feb 06 16:52:39 2012 -0800

• Add distance model constants for PannerNode according to the OpenAL spec

The changeset mentioned here is:
https://dvcs.w3.org/hg/audio/rev/7a158cdbb064

The relevant changes in the source of the spec were:
https://dvcs.w3.org/hg/audio/rev/7a158cdbb064#l1.74
(up to line 88)

This part of the spec has since been deprecated and are now only present in the (non normative) deprecation note.

The change set mentioned above also happens to be the only one ever mentioning OpenAL.

Based on the above, my conclusion would be that there is no significant borrowing/influence from OpenAL in the web audio API, other than similarities which would occur naturally since the concepts and mathematical basis for the two are the same. This conclusion was deemed reasonable by the W3C legal team.

[olivierthereaux]

Original comment by Olivier Thereaux on W3C Bugzilla. Tue, 27 Aug 2013 10:27:11 GMT

(In reply to comment #1)

Based on the above, my conclusion would be that there is no significant
borrowing/influence from OpenAL in the web audio API, other than
similarities which would occur naturally since the concepts and mathematical
basis for the two are the same. This conclusion was deemed reasonable by the
W3C legal team.

As a next step, I would suggest:

• We remove the mention "same as OpenAL (default 1)" from section 4.15
• We review whether the two mentions of OpenAL (and other engines) in informative text are needed and useful for the comprehension of the spec.

[padenot]

We should remove the first occurrence, but other occurrences are useful to understand the reasons behind the design of this API.

[billhofmann]

NOTE that there are currently only two references to OpenAL - Section 6.1 first paragraph ("A common feature requirement for modern 3D games is the ability to dynamically spatialize and move multiple audio sources in 3D space. Game audio engines such as OpenAL, FMOD, Creative's EAX, Microsoft's XACT Audio, etc. have this ability.") and Section 7.2 ("A key feature of many game audio engines (OpenAL, FMOD, Creative's EAX, Microsoft's XACT Audio, etc.) is a reverberation effect"...). This issue would seem to be addressed. Recommend close as Could Not Reproduce.

[joeberkovitz]

@billhofmann looks to me like we're good; closing now.