- From: Silvia Pfeiffer <silviapfeiffer1@gmail.com>
- Date: Thu, 19 May 2011 10:36:13 +1000
- To: HTML Accessibility Task Force <public-html-a11y@w3.org>
In today's call we discussed what to do about the new information about "clean audio" as dug up by Sean. We are considering the following and would like to ask for your thoughts / concerns / objections. 1. Dealing with "clean audio" in the Web Audio API "Clean audio" is a technology that is being standardized by ETSI [1] and EBU [2] in Europe. It is being defined on the audio channel level, i.e. the level in which stereo is handled, too. For example, it defines that the center channel in a 5.1 audio channel mix would consist only of speech and could be amplified separately to all the other channels. It is important to understand that it is being defined on the audio channel level and not the audio track level. Therefore, trying to add a track kind of "clean audio" to the track API of HTML media elements is not going to work since this doesn't allow us to separately control the volume of the "clean audio" channel in comparison to the other channels. The suggestion here is that this problem will be solved through the Web Audio API. The Web Audio API indeed has controls for separately addressing channels and changing the mix of different channels [3]. Therefore, the "clean audio" use case seems to be appropriately solved through Web Audio API means. 2. Rename @track="clear audio" to @kind="speech" While "clean audio" refers to a particular type of technology which works on the channel level, the idea of providing a separate stream of speech-only audio data that can be controlled seaprately in volume to the normal/background audio is appealing and also allows to achieve the "clean audio" effect, since it allows users to separately control the volume of a speech track. This is not the "clean audio" technology, so we should not use that same name for such a track. Therefore, the suggestion is to call such a track "speech", which seems semantically appropriate. This will then require us to change the request in the @kind bug [4] from asking for @kind="clearaudio" to @kind="speech". It would also close the multitrack bug [5]. We plan to make those changes to these bugs after next week's phone call, so hereby ask for input from everyone. In particular if you know a "clean audio" expert, please ask him/her for advice on whether this is the right way to approach it. Best Regards, Silvia. [1] http://www.etsi.org/deliver/etsi_ts/101100_101199/101154/01.09.01_60/ts_101154v010901p.pdf [2] http://tech.ebu.ch/docs/tech/tech3333.pdf [3] http://www.w3.org/2011/audio/ [4] http://www.w3.org/Bugs/Public/show_bug.cgi?id=12544 [5] http://www.w3.org/Bugs/Public/show_bug.cgi?id=11593
Received on Thursday, 19 May 2011 00:37:00 UTC