How to make speaker render silence output for 2 sec in ALSA ( Advanced Linux Sound Architecture)
0
I want make the audio speaker on a computer silence for 2 sec by writing 0's data to "default" device using ALSA (Advanced Linux Sound Architecture). Below is code snippet.
int val
int size = 24000;
u_char *tmp_buffer = (u_char *)malloc(size);
memset(tmp_buffer,0,size);
if ((val = snd_pcm_writei(pcm_handle, tmp_buffer, size)) == -EPIPE)
{
snd_pcm_prepare(pcm_handle);
}
else if (val < 0)
{
qDebug()<<"ERROR. Can't write to PCM device " << snd_strerror(val);
}
free(tmp_buffer);
With the above code, it render as "chuck chuck .." noise not silence .
How to render silence output to speaker for 2 sec?
linux alsa
edited Feb 15 at 1:09
JakeGould
32.2k1098141
asked Feb 15 at 1:04
Chakravarthi PradeepChakravarthi Pradeep
215
add a comment |
0
I want make the audio speaker on a computer silence for 2 sec by writing 0's data to "default" device using ALSA (Advanced Linux Sound Architecture). Below is code snippet.
int val
int size = 24000;
u_char *tmp_buffer = (u_char *)malloc(size);
memset(tmp_buffer,0,size);
if ((val = snd_pcm_writei(pcm_handle, tmp_buffer, size)) == -EPIPE)
{
snd_pcm_prepare(pcm_handle);
}
else if (val < 0)
{
qDebug()<<"ERROR. Can't write to PCM device " << snd_strerror(val);
}
free(tmp_buffer);
With the above code, it render as "chuck chuck .." noise not silence .
How to render silence output to speaker for 2 sec?
linux alsa
edited Feb 15 at 1:09
JakeGould
32.2k1098141
asked Feb 15 at 1:04
Chakravarthi PradeepChakravarthi Pradeep
215
Wouldn't leaving the speaker off and playing nothing be quieter than trying to play what ends up being "white noise"? PS. If you're asking about programming specifically, stackoverflow.com is great
– Xen2050
Feb 15 at 3:22
What are the sample format, rate, and channels?
– CL.
Feb 15 at 7:54
@CL,Sample rate 48000, channel is 2 and format is S16_LE.
– Chakravarthi Pradeep
Feb 15 at 8:47
add a comment |
0
0
0
I want make the audio speaker on a computer silence for 2 sec by writing 0's data to "default" device using ALSA (Advanced Linux Sound Architecture). Below is code snippet.
int val
int size = 24000;
u_char *tmp_buffer = (u_char *)malloc(size);
memset(tmp_buffer,0,size);
if ((val = snd_pcm_writei(pcm_handle, tmp_buffer, size)) == -EPIPE)
{
snd_pcm_prepare(pcm_handle);
}
else if (val < 0)
{
qDebug()<<"ERROR. Can't write to PCM device " << snd_strerror(val);
}
free(tmp_buffer);
With the above code, it render as "chuck chuck .." noise not silence .
How to render silence output to speaker for 2 sec?
linux alsa
edited Feb 15 at 1:09
JakeGould
32.2k1098141
asked Feb 15 at 1:04
Chakravarthi PradeepChakravarthi Pradeep
215
I want make the audio speaker on a computer silence for 2 sec by writing 0's data to "default" device using ALSA (Advanced Linux Sound Architecture). Below is code snippet.
int val
int size = 24000;
u_char *tmp_buffer = (u_char *)malloc(size);
memset(tmp_buffer,0,size);
if ((val = snd_pcm_writei(pcm_handle, tmp_buffer, size)) == -EPIPE)
{
snd_pcm_prepare(pcm_handle);
}
else if (val < 0)
{
qDebug()<<"ERROR. Can't write to PCM device " << snd_strerror(val);
}
free(tmp_buffer);
With the above code, it render as "chuck chuck .." noise not silence .
How to render silence output to speaker for 2 sec?
linux alsa
linux alsa
edited Feb 15 at 1:09
JakeGould
32.2k1098141
asked Feb 15 at 1:04
Chakravarthi PradeepChakravarthi Pradeep
215
edited Feb 15 at 1:09
JakeGould
32.2k1098141
asked Feb 15 at 1:04
Chakravarthi PradeepChakravarthi Pradeep
215
edited Feb 15 at 1:09
JakeGould
32.2k1098141
edited Feb 15 at 1:09
JakeGould
32.2k1098141
edited Feb 15 at 1:09
JakeGould
32.2k1098141
32.2k1098141
asked Feb 15 at 1:04
Chakravarthi PradeepChakravarthi Pradeep
215
asked Feb 15 at 1:04
Chakravarthi PradeepChakravarthi Pradeep
215
asked Feb 15 at 1:04
Chakravarthi PradeepChakravarthi Pradeep
215
215
Wouldn't leaving the speaker off and playing nothing be quieter than trying to play what ends up being "white noise"? PS. If you're asking about programming specifically, stackoverflow.com is great
– Xen2050
Feb 15 at 3:22
What are the sample format, rate, and channels?
– CL.
Feb 15 at 7:54
@CL,Sample rate 48000, channel is 2 and format is S16_LE.
– Chakravarthi Pradeep
Feb 15 at 8:47
add a comment |
Wouldn't leaving the speaker off and playing nothing be quieter than trying to play what ends up being "white noise"? PS. If you're asking about programming specifically, stackoverflow.com is great
– Xen2050
Feb 15 at 3:22
What are the sample format, rate, and channels?
– CL.
Feb 15 at 7:54
@CL,Sample rate 48000, channel is 2 and format is S16_LE.
– Chakravarthi Pradeep
Feb 15 at 8:47
Wouldn't leaving the speaker off and playing nothing be quieter than trying to play what ends up being "white noise"? PS. If you're asking about programming specifically, stackoverflow.com is great
– Xen2050
Feb 15 at 3:22
Wouldn't leaving the speaker off and playing nothing be quieter than trying to play what ends up being "white noise"? PS. If you're asking about programming specifically, stackoverflow.com is great
– Xen2050
Feb 15 at 3:22
What are the sample format, rate, and channels?
– CL.
Feb 15 at 7:54
What are the sample format, rate, and channels?
– CL.
Feb 15 at 7:54
@CL,Sample rate 48000, channel is 2 and format is S16_LE.
– Chakravarthi Pradeep
Feb 15 at 8:47
@CL,Sample rate 48000, channel is 2 and format is S16_LE.
– Chakravarthi Pradeep
Feb 15 at 8:47
add a comment |
1 Answer
1
active
oldest
votes
1
With a sample rate of 48000 Hz, two seconds need 96000 frames, so that is the number you need to give to snd_pcm_writei().
With four bytes per frame, the size of the temporary buffer must be 384000.
answered Feb 15 at 10:25
CL.CL.
1,321910
snd_pcm_writei(pcm_handle, tmp_buffer, 384000) for 2 sec this will render silence or noise to speaker...?
– Chakravarthi Pradeep
Feb 16 at 3:00
384000 frames would be wrong.
– CL.
Feb 16 at 9:47
I understand that temp buffer size should be 384000 (48000*2*2*2) but what should be number of frames for snd_pcm_writei?
– Chakravarthi Pradeep
Feb 16 at 10:54
The size of one frame is four bytes.
– CL.
Feb 16 at 16:33
thanks I understood (384000 /4) is number of frames.(pcm_handle, tmp_buffer, 96000)
– Chakravarthi Pradeep
Feb 17 at 9:43
add a comment |
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1 Answer
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1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
1
With a sample rate of 48000 Hz, two seconds need 96000 frames, so that is the number you need to give to snd_pcm_writei().
With four bytes per frame, the size of the temporary buffer must be 384000.
answered Feb 15 at 10:25
CL.CL.
1,321910
snd_pcm_writei(pcm_handle, tmp_buffer, 384000) for 2 sec this will render silence or noise to speaker...?
– Chakravarthi Pradeep
Feb 16 at 3:00
384000 frames would be wrong.
– CL.
Feb 16 at 9:47
I understand that temp buffer size should be 384000 (48000*2*2*2) but what should be number of frames for snd_pcm_writei?
– Chakravarthi Pradeep
Feb 16 at 10:54
The size of one frame is four bytes.
– CL.
Feb 16 at 16:33
thanks I understood (384000 /4) is number of frames.(pcm_handle, tmp_buffer, 96000)
– Chakravarthi Pradeep
Feb 17 at 9:43
add a comment |
1
With a sample rate of 48000 Hz, two seconds need 96000 frames, so that is the number you need to give to snd_pcm_writei().
With four bytes per frame, the size of the temporary buffer must be 384000.
answered Feb 15 at 10:25
CL.CL.
1,321910
snd_pcm_writei(pcm_handle, tmp_buffer, 384000) for 2 sec this will render silence or noise to speaker...?
– Chakravarthi Pradeep
Feb 16 at 3:00
384000 frames would be wrong.
– CL.
Feb 16 at 9:47
I understand that temp buffer size should be 384000 (48000*2*2*2) but what should be number of frames for snd_pcm_writei?
– Chakravarthi Pradeep
Feb 16 at 10:54
The size of one frame is four bytes.
– CL.
Feb 16 at 16:33
thanks I understood (384000 /4) is number of frames.(pcm_handle, tmp_buffer, 96000)
– Chakravarthi Pradeep
Feb 17 at 9:43
add a comment |
1
1
1
With a sample rate of 48000 Hz, two seconds need 96000 frames, so that is the number you need to give to snd_pcm_writei().
With four bytes per frame, the size of the temporary buffer must be 384000.
answered Feb 15 at 10:25
CL.CL.
1,321910
With a sample rate of 48000 Hz, two seconds need 96000 frames, so that is the number you need to give to snd_pcm_writei().
With four bytes per frame, the size of the temporary buffer must be 384000.
answered Feb 15 at 10:25
CL.CL.
1,321910
answered Feb 15 at 10:25
CL.CL.
1,321910
answered Feb 15 at 10:25
CL.CL.
1,321910
answered Feb 15 at 10:25
CL.CL.
1,321910
1,321910
snd_pcm_writei(pcm_handle, tmp_buffer, 384000) for 2 sec this will render silence or noise to speaker...?
– Chakravarthi Pradeep
Feb 16 at 3:00
384000 frames would be wrong.
– CL.
Feb 16 at 9:47
I understand that temp buffer size should be 384000 (48000*2*2*2) but what should be number of frames for snd_pcm_writei?
– Chakravarthi Pradeep
Feb 16 at 10:54
The size of one frame is four bytes.
– CL.
Feb 16 at 16:33
thanks I understood (384000 /4) is number of frames.(pcm_handle, tmp_buffer, 96000)
– Chakravarthi Pradeep
Feb 17 at 9:43
add a comment |
snd_pcm_writei(pcm_handle, tmp_buffer, 384000) for 2 sec this will render silence or noise to speaker...?
– Chakravarthi Pradeep
Feb 16 at 3:00
384000 frames would be wrong.
– CL.
Feb 16 at 9:47
I understand that temp buffer size should be 384000 (48000*2*2*2) but what should be number of frames for snd_pcm_writei?
– Chakravarthi Pradeep
Feb 16 at 10:54
The size of one frame is four bytes.
– CL.
Feb 16 at 16:33
thanks I understood (384000 /4) is number of frames.(pcm_handle, tmp_buffer, 96000)
– Chakravarthi Pradeep
Feb 17 at 9:43
snd_pcm_writei(pcm_handle, tmp_buffer, 384000) for 2 sec this will render silence or noise to speaker...?
– Chakravarthi Pradeep
Feb 16 at 3:00
snd_pcm_writei(pcm_handle, tmp_buffer, 384000) for 2 sec this will render silence or noise to speaker...?
– Chakravarthi Pradeep
Feb 16 at 3:00
384000 frames would be wrong.
– CL.
Feb 16 at 9:47
384000 frames would be wrong.
– CL.
Feb 16 at 9:47
I understand that temp buffer size should be 384000 (48000*2*2*2) but what should be number of frames for snd_pcm_writei?
– Chakravarthi Pradeep
Feb 16 at 10:54
I understand that temp buffer size should be 384000 (48000*2*2*2) but what should be number of frames for snd_pcm_writei?
– Chakravarthi Pradeep
Feb 16 at 10:54
The size of one frame is four bytes.
– CL.
Feb 16 at 16:33
The size of one frame is four bytes.
– CL.
Feb 16 at 16:33
thanks I understood (384000 /4) is number of frames.(pcm_handle, tmp_buffer, 96000)
– Chakravarthi Pradeep
Feb 17 at 9:43
thanks I understood (384000 /4) is number of frames.(pcm_handle, tmp_buffer, 96000)
– Chakravarthi Pradeep
Feb 17 at 9:43
add a comment |
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Wouldn't leaving the speaker off and playing nothing be quieter than trying to play what ends up being "white noise"? PS. If you're asking about programming specifically, stackoverflow.com is great
– Xen2050
Feb 15 at 3:22
What are the sample format, rate, and channels?
– CL.
Feb 15 at 7:54
@CL,Sample rate 48000, channel is 2 and format is S16_LE.
– Chakravarthi Pradeep
Feb 15 at 8:47