...

Does anyone have examples or documentation on how to configure

periods,

...

frames and buffers for various sample rates? I am writing a

program to

...

route a mp3 decoder output to ALSA on an ARM processor, and I

get noisy

...

audio. For a CD quality stream (S16_LE, 44100 kHz, Stereo, 128

bps) I am

...

using an output buffer of 44100 bytes, a period of

44100/(channels*2). With

...

Be careful about the distinction between bytes and frames (i.e. a frame of stereo S16 is 4 bytes)

Start with the period 1024 frames = 4096 bytes then make your buffer at least 2x this: 8192 bytes

(I'm not an app developer, so others may jump in with a better explanation)

Did you look at the code in alsa-lib/test?

Thanks Eliot, I will try this buffer size.

I did look at alsa tests, but I was not too convinced, as when I run those apps I still got plenty of short writes. Would someone please explain why do these 'short writes' occur?

...

a buffer this big, I do not get underruns, but I do get all

short writes. I

...

have not been able to find the right configuration to avoid

short writes,

...

and more importantly, to get good quality audio. What do

'short writes' (I

...

am using writei) really mean? Is this a performance issue in

the driver, or

is mainly because of buffer setup? I would really appreciate

any help with

...

this. Magdalena