0

Question about Sound Card Capture Capabilities
Moderators: adafruit_support_bill, adafruit

Forum rules
Talk about Adafruit Raspberry Pi® accessories! Please do not ask for Linux support, this is for Adafruit products only! For Raspberry Pi help please visit: http://www.raspberrypi.org/phpBB3/
Please be positive and constructive with your questions and comments.

Question about Sound Card Capture Capabilities

by jcdale on Fri May 10, 2019 2:41 pm

Greetings;

I'm picking-up a sound card for my RP.

I run Raspbian on a PiII.

Currently, I'm using Java to capture 44k mono unsigned PCM on a mac.

What can I expect in terms of Wav format capture from this (I can adjust my code):
https://www.adafruit.com/product/1475

Sincerely,

John

jcdale
 
Posts: 4
Joined: Fri May 10, 2019 2:37 pm

Re: Question about Sound Card Capture Capabilities

by adafruit_support_mike on Sat May 11, 2019 4:07 am

The CM-type adapters can do 44.1 audio, so that shouldn't be a problem.

adafruit_support_mike
 
Posts: 58887
Joined: Thu Feb 11, 2010 2:51 pm

Re: Question about Sound Card Capture Capabilities

by jcdale on Sat May 11, 2019 8:33 am

adafruit_support_mike wrote:The CM-type adapters can do 44.1 audio, so that shouldn't be a problem.


Very good news - can't wait!

jcdale
 
Posts: 4
Joined: Fri May 10, 2019 2:37 pm

Re: Question about Sound Card Capture Capabilities

by jcdale on Thu Jun 13, 2019 12:14 am

Greetings;

So, I got the sound card and with no modification I could capture and process my audio stream!

Lovely.

However, I can't seem to stop the target data line in Java.

I read up on this a little and discovered some issues with little vs big endian, but in examining my code, I was in compliance.

Here's my target format .. when I call "drain" and "close" on the target data line, it doesn't stop .. just keeps on capturing:

final AudioFormat format = new AudioFormat(44100.0F, 16, 1, true, false);

Any ideas?

Again, just to note, I can capture the audio just fine and process .. just can't stop!

Sincerely,

John

jcdale
 
Posts: 4
Joined: Fri May 10, 2019 2:37 pm

Re: Question about Sound Card Capture Capabilities

by adafruit_support_mike on Sat Jun 15, 2019 12:38 am

I'm afraid we don't know much about Java on the RasPi, but we do know the whole Linux audio system is arcane and poorly documented.

You might want to check with the folks over at the RasPi Foundation forums:

http://www.raspberrypi.org/forums/

They know more about what Raspbian does under the hood.

adafruit_support_mike
 
Posts: 58887
Joined: Thu Feb 11, 2010 2:51 pm

Please be positive and constructive with your questions and comments.