But are you sure you are getting the sample rate you asked for? How would
you know? As you can see from my very first posting, all the checks you
are doing here work fine for me too, and I actually do get the number of
samples per second I ask for. But they are not true samples. They have
been faked by up-sampling. The system takes 8000 samples per second and
then duplicates each sample enough times to make up 44100 or 22050 or
whatever. But I know those samples are not true samples because I see
aliasing around 4000 Hz in the frequency spectrum. Unless you specifically
look for this problem by testing with a pure tone above 4000 Hz and analyze
with an FFT and look for aliasing below 4000 Hz, everything will appear
fine. Again this only happens on a very few models - specifically the LG
G3 and the Asus Nexus 7.
On Wednesday, January 27, 2016 at 10:57:45 AM UTC-6, Julian Bunn wrote:
>
> Yes, that looks fine to me ... In case it helps, here is a snippet of what
> I do to check a samplerate is going to work:
>
> minBuffer = AudioRecord
> .getMinBufferSize(rate, config, encoding);
> if (minBuffer != AudioRecord.ERROR_BAD_VALUE
> && minBuffer != AudioRecord.ERROR) {
> boolean bGood = true;
> try {
> audio = new AudioRecord(audioSource, rate, config,
> encoding, minBuffer);
> int istate = audio.getState();
> if (istate != AudioRecord.STATE_INITIALIZED)
> bGood = false;
> } catch (Exception e) {
> bGood = false;
> }
> audio.release();
> audio = null;
> if (bGood)
> return rate;
>
>
> On Tuesday, January 26, 2016 at 12:49:46 PM UTC-8, RLScott wrote:
>>
>> I am calling
>> AudioRecord.getMinBufferSize(44100,AudioFormat.CHANNEL_IN_MONO,AudioFormat.ENCODING_PCM_16BIT)
>>
>> and using the returned minAudioRecordBufSize in
>>
>> new AudioRecord(MediaRecorder.AudioSource.MIC,
>> 44100,AudioFormat.CHANNEL_IN_MONO,
>> AudioFormat.ENCODING_PCM_16BIT, minAudioRecordBufSize);
>>
>> Is that sizing the buffers correctly?
>>
>> Thanks for the offer for the enumeration app, but I do not have a failing
>> device at my disposal. Only a few devices are failing, and they are all
>> owned by my customers. I can't ask too much of them in the way of
>> debugging help.
>>
>>
>> On Friday, January 15, 2016 at 1:34:15 AM UTC-6, Julian Bunn wrote:
>>>
>>> Make sure you are sizing the buffers correctly i.e. respecting the
>>> minimum recording buffer size (in bytes) required. If you don't then I
>>> believe the system will drop you down to 8kHz sample rate, which is what
>>> you are seeing (I think?).
>>>
>>>
>>> On Wednesday, December 23, 2015 at 9:52:37 AM UTC-8, Robert Scott wrote:
>>>>
>>>> I first call *AudioRecord.getMinBufferSize(22050...* If this returns
>>>> an error (<1) then I call *AudioRecord.getMinBufferSize(44100...*
>>>> Whichever one of these calls succeeds, I use that rate in my call to "*new
>>>> AudioRecord(..,sampleRate..)*"
>>>>
>>>> I don't actually have one of these misbehaving devices, so my
>>>> experiments so far have been with the help of my customers.
>>>>
>>>> -Robert Scott
>>>> Hopkins, MN
>>>>
>>>>
--
You received this message because you are subscribed to the Google Groups
"Android Developers" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to android-developers+unsubscr...@googlegroups.com.
To post to this group, send email to android-developers@googlegroups.com.
Visit this group at https://groups.google.com/group/android-developers.
To view this discussion on the web visit
https://groups.google.com/d/msgid/android-developers/c04a2d86-42bd-46dc-892e-4ef32b4b6759%40googlegroups.com.
For more options, visit https://groups.google.com/d/optout.
