Re: R18. User perceived latency of synthesis must be minimized

On Fri, Nov 5, 2010 at 10:57 AM, Olli Pettay <Olli.Pettay@helsinki.fi>wrote:

> On 11/05/2010 08:42 AM, Robert Brown wrote:
>
>> Agreed that the server case is out of scope.  I wonder if there's
>> anything that could be said about the client.  Perhaps it could be
>> rewritten as "user agents should provide/playback rendered TTS audio
>> to the app immediately as it's received from the TTS service".
>>
> This might be actually quite "wrong" wording if we're going to
> extend HTML5's media elements to provide TTS.
> The application may want to cache the result from TTS engine before
> playing it out.


Yes, such wording would prohibit the HTMLMediaElement autobuffer attribute
from working, which ironically would increase latency.

I think that the only point of a latency requirement would be to make sure
that spec proposals don't prohibit low-latency processing. For example, a
spec that requires that audio capture must finish without the user aborting
it before any audio transmission or speech processing is allowed to take
place would force high latency in implementations.

For recognition latency (the next requirement), maybe something like this
would be appropriate: "Implementations should be allowed to start processing
captured audio before the capture completes." For TTS, I don't think that
such a requirement is needed, since the text to synthesize is typically
available immediately (as opposed to captured audio which becomes available
at a fixed rate).



 Hmm... could do with better wording, and may be just stating the
>> obvious.
>>
>> -----Original Message----- From: Satish Sampath
>> [mailto:satish@google.com] Sent: Thursday, November 04, 2010 3:08 PM
>> To: Robert Brown Cc: Bjorn Bringert; Dan Burnett;
>> public-xg-htmlspeech@w3.org Subject: Re: R18. User perceived latency
>> of synthesis must be minimized
>>
>> This seems more of a requirement on the speech service which
>> synthesizes the audio, than the UA, since usually the complexity lies
>> in the synthesizer. I equate this to a requirement like 'web pages
>> must load as fast as possible' which in reality turns into 'web
>> servers should process received requests as fast as they can' and the
>> latter is really up to the implementation based on a lot of factors
>> which are not in the control of the UA.
>>
>> If we agree that to be the case, I think it is out of scope.
>>
>> Cheers Satish
>>
>>
>>
>> On Thu, Nov 4, 2010 at 10:22 PM, Robert
>> Brown<Robert.Brown@microsoft.com>  wrote:
>>
>>> It may just be a requirement that's really obvious.
>>>
>>>
>>>
>>> From: public-xg-htmlspeech-request@w3.org
>>> [mailto:public-xg-htmlspeech-request@w3.org] On Behalf Of Bjorn
>>> Bringert Sent: Thursday, November 04, 2010 1:27 PM To: Dan Burnett
>>> Cc: public-xg-htmlspeech@w3.org Subject: Re: R18. User perceived
>>> latency of synthesis must be minimized
>>>
>>>
>>>
>>> I don't see a need for this to be a requirement. It's up to
>>> implementations to be fast, and it's unrealistic to set any
>>> specific latency limits.
>>>
>>>
>>>
>>> On Thu, Nov 4, 2010 at 9:23 PM, Dan Burnett<dburnett@voxeo.com>
>>> wrote:
>>>
>>> Group,
>>>
>>> This is the next of the requirements to discuss and prioritize
>>> based on our ranking approach [1].
>>>
>>> This email is the beginning of a thread for questions, discussion,
>>> and opinions regarding our first draft of Requirement 18 [2].
>>>
>>> Please discuss via email as we agreed at the Lyon f2f meeting.
>>> Outstanding points of contention will be discussed live at the next
>>> teleconference.
>>>
>>> -- dan
>>>
>>> [1]
>>> http://lists.w3.org/Archives/Public/public-xg-htmlspeech/2010Oct/0024.
>>>
>>>
>>>  html [2]
>
>> http://lists.w3.org/Archives/Public/public-xg-htmlspeech/2010Oct/att-0
>>>
>>>
>>>  001/speech.html#r18
>
>>
>>>
>>> -- Bjorn Bringert Google UK Limited, Registered Office: Belgrave
>>> House, 76 Buckingham Palace Road, London, SW1W 9TQ Registered in
>>> England Number: 3977902
>>>
>>
>>
>>
>>
>


-- 
Bjorn Bringert
Google UK Limited, Registered Office: Belgrave House, 76 Buckingham Palace
Road, London, SW1W 9TQ
Registered in England Number: 3977902