From mboxrd@z Thu Jan 1 00:00:00 1970 Content-Type: multipart/mixed; boundary="===============0502492649371308508==" MIME-Version: 1.0 From: Denis Kenzior Subject: Re: [PATCH v1 1/7] doc: Add EchoCancelingNoiseReduction to Handsfree Date: Mon, 22 Apr 2013 06:56:36 -0500 Message-ID: <51752574.7010705@gmail.com> In-Reply-To: List-Id: To: ofono@ofono.org --===============0502492649371308508== Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Hi Claudio, On 04/22/2013 11:46 AM, Claudio Takahasi wrote: > Hi Denis: > > On Mon, Apr 22, 2013 at 6:04 AM, Denis Kenzior wrot= e: >> Hi Claudio, >> >> >> On 04/22/2013 07:58 AM, Claudio Takahasi wrote: >>> >>> This patch adds echo canceling and noise reduction property to Handsfree >>> interface, allowing the handsfree unit to enable or disable this feature >>> in the audio gateway. >>> >>> According to Bluetooth HFP 1.6 spec: By default, if the AG supports its >>> own embedded echo canceling and/or noise reduction functions, it shall >>> have them activated until the AT+NREC command is received. >>> --- >>> doc/handsfree-api.txt | 7 +++++++ >>> 1 file changed, 7 insertions(+) >>> >>> diff --git a/doc/handsfree-api.txt b/doc/handsfree-api.txt >>> index 0b5d421..6855d93 100644 >>> --- a/doc/handsfree-api.txt >>> +++ b/doc/handsfree-api.txt >>> @@ -56,6 +56,13 @@ Properties array{string} Features [readonly] >>> to activate or deactivate the function from the >>> HF, or >>> the AG could autonomously initiate it. >>> >>> + boolean EchoCancelingNoiseReduction [readwrite] >>> + >>> + Boolean representing whether echo canceling and >>> noise >>> + reduction is enabled in the AG. This property m= ay >>> be >>> + written to activate or deactivate this feature >>> from >>> + the HF unit. >>> + >> >> >> This feature can only be disabled, not enabled for a given SLC. So sett= ing >> this to 'True' should return an error or do something way fancier. >> >> I suspect that to implement this properly we need to store the ECNR sett= ing >> on disk (e.g. /var/lib/ofono///handsfree or >> something) and manage it appropriately inside the core. > > It is true, the HFP spec defines the procedure to disable it only. > I implemented an option to disable it because I noticed different > behavior between the phones/modems. Anyway, I will remove it, we can > extend the API later if necessary. This interface is specific to HFP, so don't worry about real modems. > > Regarding the storage, the spec (page 53) is a little bit confusing to > me, I understood that the AG will enable it again when the connection > is dropped. So, we don't need to stored it. > In theory we could remember the previous setting and just simply send it = automatically the next time a device is connected. However, your = approach will be fine for now. Regards, -Denis --===============0502492649371308508==--