Please reply to my last question in this thread~

On Nov 5, 11:06 am, ani <[email protected]> wrote:
> Hack,
>
> I just want one information.When i am playing music+ringtone in that
> case there will be a buffer for both the sounds.
>
> questions are:
> a.These mixing of buffers takes place in audiomixer.cpp?
> b.If i increase of decrease the volume of music,am i increasing or
> decreasing the gain of codec or is it taken care by audiomixer while
> mixing the buffers?
>
> Thanks in advance.
>
> On Sep 16, 10:15 am, Dianne Hackborn <[email protected]> wrote:
>
> > Like I said, I can't help you at this level of detail.  I wouldn't be
> > surprised if everything is going through the global mixer though.
>
> > 2009/9/15 Andy <[email protected]>
>
> > > Hi Dianne Hackborn,
>
> > > Then may I know if every audio stream that you mentioned in different
> > > modes (e.g. ringer volume, media volume, etc.) is always going through
> > > a mixer for audio processing? For such a mixer, does it mean the
> > > source file AudioMixer.cpp? I would be appreciated for your further
> > > comments.
>
> > > On 9月16日, 上午10時24分, Dianne Hackborn <[email protected]> wrote:
> > > > Sorry I can't help you with codecs, maybe somebody else can.
>
> > > > 2009/9/15 Andy <[email protected]>
>
> > > > > Dianne Hackborn, thanks for your comments.
>
> > > > > Right, I know this about the ringer and media volumes. But what I
> > > > > concern here is how to set the volume level gain in the real hardware
> > > > > codec driver (instead of the "software" volume change if it is) when
> > > > > the volume level is changed in the Android. Here is more observations
> > > > > that I missed to mention in the case:
>
> > > > > 1. When playback a song and make changed the volume level in the
> > > > > Android, I observe the media volume is using. For what I observed, the
> > > > > "software" volume is somehow using as I mentioned before.
>
> > > > > 2. When not in music playback, I observe the ringer volume is using.
> > > > > If I make changed the volume level in this case, I found the
> > > > > corresponding hardware codec driver is called to set the volume gain
> > > > > (i.e. I can see the corresponding codec registers changed by
> > > > > alsa_amixer). However, what I found the LOGCAT is strange. The codec
> > > > > driver is merely called to set zero volume level first (i.e. 0 value)
> > > > > and then set back to its maximum value (i.e. 255 value out of the
> > > > > maximum 255 level).
>
> > > > > As I need to ensure that the direct hardware codec driver is called
> > > > > for audio quality concern, I need to be clear of what happens here or
> > > > > what is going wrong with some settings in my case.
>
> > > > > What can I do? Thanks!
>
> > > > > On 9月16日, 上午4時07分, Dianne Hackborn <[email protected]> wrote:
> > > > > > You aren't adjusting the overall volume level, you are adjusting the
> > > > > volumes
> > > > > > of one of the streams being mixed.  Typically by default you are
> > > > > adjusting
> > > > > > the ringer volume, and if playing media you will be adjusting the
> > > media
> > > > > > volume.
>
> > > > > > On Tue, Sep 15, 2009 at 3:10 AM, Andy <[email protected]> wrote:
>
> > > > > > > Hi all,
>
> > > > > > > I found in my Android platform that everytime when I adjust the
> > > volume
> > > > > > > level (i.e. press the volume key +/-), it seems a software volume
> > > > > > > control scheme is used (Instead, I expect a direct function call 
> > > > > > > to
> > > a
> > > > > > > codec hardware driver, and changing audio gain in corresponding
> > > > > > > registers).
>
> > > > > > > I found this using the alsa_amixer to list out the volume change 
> > > > > > > in
> > > a
> > > > > > > "Master Volume" element. Here is what I figure out this following
> > > the
> > > > > > > sequence below:
>
> > > > > > > 1. After bootup, monitor the current volume level of the "Master
> > > > > > > Volume" element using the alsa_amixer. The GET value is 255 out of
> > > the
> > > > > > > maximum 255.
>
> > > > > > > 2. Playback a song using the Android music player.
>
> > > > > > > 3. Adjust the volume level in the Android to see if there is
> > > changed
> > > > > > > in the "Master Volume" status.
>
> > > > > > > 4. I found I can hear the change in the headphone audio output, 
> > > > > > > but
> > > > > > > the "Master Volume" element still keeps the value 255 no matter I
> > > > > > > changed the volume from the lowest to the highest.
>
> > > > > > > I would like to disable this software volume if it is really using
> > > and
> > > > > > > use the hardware. Does anyone have any idea about what is going on
> > > in
> > > > > > > my case? Thanks!!!
>
> > > > > > --
> > > > > > Dianne Hackborn
> > > > > > Android framework engineer
> > > > > > [email protected]
>
> > > > > > Note: please don't send private questions to me, as I don't have 
> > > > > > time
> > > to
> > > > > > provide private support, and so won't reply to such e-mails.  All
> > > such
> > > > > > questions should be posted on public forums, where I and others can
> > > see
> > > > > and
> > > > > > answer them.- 隱藏被引用文字 -
>
> > > > > > - 顯示被引用文字 -
>
> > > > --
> > > > Dianne Hackborn
> > > > Android framework engineer
> > > > [email protected]
>
> > > > Note: please don't send private questions to me, as I don't have time to
> > > > provide private support, and so won't reply to such e-mails.  All such
> > > > questions should be posted on public forums, where I and others can see
> > > and
> > > > answer them.- 隱藏被引用文字 -
>
> > > > - 顯示被引用文字 -
>
> > --
> > Dianne Hackborn
> > Android framework engineer
> > [email protected]
>
> > Note: please don't send private questions to me, as I don't have time to
> > provide private support, and so won't reply to such e-mails.  All such
> > questions should be posted on public forums, where I and others can see and
> > answer them.- Hide quoted text -
>
> > - Show quoted text -
>
>

-- 
unsubscribe: [email protected]
website: http://groups.google.com/group/android-porting

Reply via email to