- From: Richards, Jan <jrichards@ocadu.ca>
- Date: Tue, 6 Oct 2015 17:17:44 +0000
- To: "public-mobile-a11y-tf@w3.org" <public-mobile-a11y-tf@w3.org>
Hi Patrick, I don't think there can bright line between mobile and non-mobile, as we tried to explain in the note: http://www.w3.org/TR/mobile-accessibility-mapping/#wcag-2.0-and-mobile-content-applications Do you think there is anything more that needs to be added to that section? Cheers, Jan (MR) JAN RICHARDS PROJECT MANAGER INCLUSIVE DESIGN RESEARCH CENTRE (IDRC) OCAD UNIVERSITY T 416 977 6000 x3957 F 416 977 9844 E jrichards@ocadu.ca ________________________________________ From: Patrick H. Lauke [redux@splintered.co.uk] Sent: October-06-15 1:10 PM To: public-mobile-a11y-tf@w3.org Subject: Re: Fwd: Screen Reader Audio on Mobile Is this not already covered by UAAG 2.0 http://www.w3.org/TR/UAAG20/#gl-volume-config ? I don't personally feel this needs to be singled out specifically for mobile/tablet devices. Incidentally, on a more general note (and I'm sure this was touched on before): do we have a definition of what constitutes "mobile"? Are laptops with a touchscreen "mobile"? Devices like the Surface which have a detachable/optional keyboard/trackpad, and blur the line between tablet and laptop? P On 06/10/2015 17:27, David MacDonald wrote: > Hi Team > > Please consider this request by Janina, the chair of the Protocols > Working group regarding her experience as a blind person on an iPhone. > It is really a user agent issue but we may want to take up this cause on > the user agent sside of things. > > > > ---------- Forwarded message ---------- > From: *Janina Sajka* <janina@rednote.net <mailto:janina@rednote.net>> > Date: Mon, Oct 5, 2015 at 8:10 PM > Subject: Screen Reader Audio on Mobile > To: David MacDonald <david100@sympatico.ca <mailto:david100@sympatico.ca>> > > > Hi, David: > > In a telephone conversation some weeks hence, you asked that I provide > you my architectural concerns about why TTS audio on mobile should be > managed as a separate audio channel. My apologies for taking so long to > provide this to you! > > BACKGROUND: There are multiple sources of audio on mobile devices. > These sources include incoming audio in a telephone call, music that a > user might have stored in nonvolatile memory on the device, audio for > movies (and other video) stored on, or streamed to a mobile device, > sounds for use as alarms (or other audible markers of system activity), > and synthetic Text to Speech (TTS) engines commonly used with screen > readers by users who are blind. Combining these various sources into a > single audio presentation that can be heard when a phone is held to one > ear, or that can play in stereo through a pair of speakers on a tablet > device, is > called "mixing" by audio processing professionals. When and how this > mixing occurs, however, impacts the level of reliability and performance > the user will experience. It is my contention here that the screen > reader user is porrly served on today's devices as a result of > inadequate audio design considerations. > > THE PROBLEM: Both IOS and Android lump TTS audio together into what's > called the same "audio channel." This unfortunate architectural design > decision creates functional problems for users who rely on TTS > including: > > * It's harder to independently manage TTS volume vis a vis volume > * of other audio events. This is true also for other audio > * characteristics such as eq, panning, etc. > > * It's impossible to independently direct audio output. If the > * user wants movie audio to go to an external Bluetooth soundbar, > * she must accept that the TTS will also now be heard via those > * same Bluetooth speakers. This makes no sense from a > * functionality perspective inasmuch as the TTS is ostensibly part > * of a highly interactive user interface paradigm, whereas the > * movie audio is simply presentational. Lag times for TTS matter a > * lot, but for movie audio only synchronization with the video > * matters. > > * It's impossible for TTS events to be properly prioritized when > * they're lumped together with other audio events this way. > * Because TTS is part of a highly interactive user interface, its > * system priority should always remain quite high, and should > * remain closely correlated to on screen touch events. This breaks > * down when prioritization is driven by playback of presentational > * audio such as music or movie/video sound tracks. One result of > * such inappropriate prioritization is also the poor performance > * of DTMF after the completion of a telephone call. Both IOS and > * Android are very poor at this for reasons of inappropriate > * system event prioritization. > > THE SOLUTION: With today's more powerful, multi-core CPUs, and with > today's independent audio management subsystems, it's perfectly > reasonable to request a better architecture for TTS dependent user > interfaces. The TTS used by screen readers should be managed in its own > audio channel until the final mixdown for speaker/headset presentation. > > Thank you, David, for conveying this concern to the Mobile A11y TF on my > behalf. > > Janina > > > > -- > > Janina Sajka, Phone: +1.443.300.2200 <tel:%2B1.443.300.2200> > sip:janina@asterisk.rednote.net <mailto:sip%3Ajanina@asterisk.rednote.net> > Email: janina@rednote.net <mailto:janina@rednote.net> > > Linux Foundation Fellow > Executive Chair, Accessibility Workgroup: http://a11y.org > > The World Wide Web Consortium (W3C), Web Accessibility Initiative (WAI) > Chair, Protocols & Formats http://www.w3.org/wai/pf > > > -- Patrick H. Lauke www.splintered.co.uk | https://github.com/patrickhlauke http://flickr.com/photos/redux/ | http://redux.deviantart.com twitter: @patrick_h_lauke | skype: patrick_h_lauke
Received on Tuesday, 6 October 2015 17:18:15 UTC