24 Jul
2010
24 Jul
'10
10:06 p.m.
Hello.
Just a follow up to something I said a while back.
I think Gene H. was saying he couldn't get audio
and I had replied that I disabled Pulse and it
appeared to be working.
But even after disabling Pulse, sometimes I still was
not getting audio in Flash on YouBoob etc.
When I did have audio, I noticed that every video's
audio seemed slower and lower in pitch.
I was fooled into thinking that the owners of the
videos had somehow remixed them at lower
pitches or something.
It turns out that Flash wants to play everything
at a 48000Hz sample rate.
Since my audio card is an Envy24 based card,
it always boots up in 44100Hz sample rate mode.
So now, before I play Flash videos, I must open the
envy24control mixer and set the sample rate to 48000Hz.
It works every time now !
Can someone explain the process of how Flash plays audio,
and how to force it to use 44100Hz?
I'm confused because at 44100Hz the audio is in sync
with the video, yet it is lower in pitch and slower.
Does this mean Flash is really playing the video slower?
Thanks. Tim.
24 Jul
24 Jul
11:54 p.m.
As usual, the nature of the problem becomes clearer
immediately after I form my question and post it.
So let me re-phrase the problem and question:
I think these issues are part of a more general
bug with ALSA + envy24.
ALSA is not able to change the envy24's sample rate.
This requires the user to manually set the rate in the
envy24control mixer before starting any ALSA based app.
With Flash, it is simply playing through ALSA using
whatever the default ALSA sample rate is.
In this case that's 48000Hz, (or so each *believes*).
But the true rate is set by the envy24control mixer
which by default is 41000Hz.
Thus when playing Flash videos, the audio is the wrong
pitch and too slow.
I now recall Amarok has the same problem.
And certainly, when starting Jack with the ALSA back end, I must
set Jack's sample rate to match envy24control's sample rate.
Otherwise the audio is wrong.
So the solution is one of the following:
1) Fix the bug. ALSA should change the envy24's sample rate.
2) Change the default ALSA sample rate to 44100Hz. (How to do that??)
3) Do it on an app by app basis setting each app's sample rate
to match envy24's rate.
The original question is still valid though - even if the bug was fixed
and ALSA was able to set envy24 to 48000Hz when starting Flash,
what if I want to play Flash videos at 44100Hz? How to do that?
These issues may have been fixed in the year or so since my
current distro. Must check.
Thanks again. Tim.
On July 24, 2010 03:54:19 pm Tim E. Real wrote:
Hello.
Just a follow up to something I said a while back.
I think Gene H. was saying he couldn't get audio
and I had replied that I disabled Pulse and it
appeared to be working.
But even after disabling Pulse, sometimes I still was
not getting audio in Flash on YouBoob etc.
When I did have audio, I noticed that every video's
audio seemed slower and lower in pitch.
I was fooled into thinking that the owners of the
videos had somehow remixed them at lower
pitches or something.
It turns out that Flash wants to play everything
at a 48000Hz sample rate.
Since my audio card is an Envy24 based card,
it always boots up in 44100Hz sample rate mode.
So now, before I play Flash videos, I must open the
envy24control mixer and set the sample rate to 48000Hz.
It works every time now !
Can someone explain the process of how Flash plays audio,
and how to force it to use 44100Hz?
I'm confused because at 44100Hz the audio is in sync
with the video, yet it is lower in pitch and slower.
Does this mean Flash is really playing the video slower?
Thanks. Tim.
_______________________________________________
Linux-audio-dev mailing list
Linux-audio-dev(a)lists.linuxaudio.org
http://lists.linuxaudio.org/listinfo/linux-audio-dev
25 Jul
25 Jul
12:44 a.m.
For the alsa "default" device, as used by web-apps and other things
where you haven't explicitly set the device, consider using a "dmix"
device such as done in http://nielsmayer.com/npm/dot-asoundrc.txt
What would be more interesting, and I haven't explored yet, would be
to combine the "dmix" and "dshare" examples from the file above,
which
would allow reserving a single stereo pair for "default" that would
resample to 44.1K no matter what the sample rate -- thus no diddling
around between playing web video @ 48K versus audio @ 44.1K.
See 66ch12 66ch34 66ch56 66ch78 66spdif for the dshare devices made
out of a single ice1712 device (Delta 66). So if "default" is assigned
to channels 1+2, I could still use
devices 66ch34 66ch56 66ch78 or 66spdif to access other outputs,
independently of whether a web browser has tied up channels 1/2. (too
bad jackd won't work (?) with such a configuration of "sharing" part
of a card via ALSA dshare -- last time I tried it treated the card as
"busy" until I released resources associated with the remaining
dshare'd part of the card)
Another example of a dmix'd default device -- an ICE1724 --
http://nielsmayer.com/npm-dynex-asoundrc.txt which also duplicates the
stream to both analog (i.e. headphone out) and SPDIF outputs
simultaneously. Although now that I understand this card better, for
the particular example of a dynex dx-sc51 I'd run it at 48K because of
the particular AC97 codec used on this $0.99 best-buy special.
Niels
http://nielsmayer.com
PS: ob-envy24: I'm close to releasing my improvements of
envy24control. Just one more bug to fix. Some screenshots:
http://nielsmayer.com/envy24control/Screenshot-Envy24Control-AnalogVolume.p…
http://nielsmayer.com/envy24control/Screenshot-Envy24Control-MonitorInputs.…
http://nielsmayer.com/envy24control/Screenshot-Envy24Control-MonitorPCM.png
5:55 a.m.
On July 24, 2010 06:44:40 pm you wrote:
For the alsa "default" device, as used by
web-apps and other things
where you haven't explicitly set the device, consider using a "dmix"
device such as done in http://nielsmayer.com/npm/dot-asoundrc.txt
I've battled
with .asoundrc before so I know my way around a bit.
Been a while since I looked at dmix.
If I run at say 128 Jack frames, will dmix slow things appreciably,
particularly with a complex .asoundrc ?
What would be more interesting, and I haven't explored yet, would be
to combine the "dmix" and "dshare" examples from the file above,
which
would allow reserving a single stereo pair for "default" that would
resample to 44.1K no matter what the sample rate -- thus no diddling
around between playing web video @ 48K versus audio @ 44.1K.
See 66ch12 66ch34 66ch56 66ch78 66spdif for the dshare devices made
out of a single ice1712 device (Delta 66). So if "default" is assigned
to channels 1+2, I could still use
devices 66ch34 66ch56 66ch78 or 66spdif to access other outputs,
independently of whether a web browser has tied up channels 1/2. (too
bad jackd won't work (?) with such a configuration of "sharing" part
of a card via ALSA dshare -- last time I tried it treated the card as
"busy" until I released resources associated with the remaining
dshare'd part of the card)
Another example of a dmix'd default device -- an ICE1724 --
http://nielsmayer.com/npm-dynex-asoundrc.txt which also duplicates the
stream to both analog (i.e. headphone out) and SPDIF outputs
simultaneously. Although now that I understand this card better, for
the particular example of a dynex dx-sc51 I'd run it at 48K because of
the particular AC97 codec used on this $0.99 best-buy special.
This would be
handy.
Niels
http://nielsmayer.com
PS: ob-envy24: I'm close to releasing my improvements of
envy24control. Just one more bug to fix. Some screenshots:
http://nielsmayer.com/envy24control/Screenshot-Envy24Control-AnalogVolume.p
ng
http://nielsmayer.com/envy24control/Screenshot-Envy24Control-MonitorInputs.
png
http://nielsmayer.com/envy24control/Screenshot-Envy24Control-MonitorPCM.png
Holy crud that's nice !!! You really went to town on this !
How the heck did you manage the slider markings, after I posted I thought it
was impossible to satisfy, especially with different cards ?
Cheers. Tim.
6:06 p.m.
On Sat, Jul 24, 2010 at 8:43 PM, Tim E. Real <termtech(a)rogers.com> wrote:
On July 24, 2010 06:44:40 pm you wrote:
Holy crud that's nice !!! You really went to town on this !
I figured these cards are worth it... One of the changes I made
seriously reduces the number of interrupts/ticks envy24control 0.6.0
generates, by replacing a bunch of 100ms timers with a single 100ms
timer. And not updating the hardware meters across umpteen channels at
25 times a second. Which IMHO is hardware peak-metering abuse -- if
you really need to visualize your sound in realtime, you might as well
just run "jkmeter" or "yass" on the inputs or outputs and be done
with
it.... I want to be able to have 'envy24control' up and running all
the time, using hardware peak meters to monitor the levels without
significantly increasing CPU processing, and with metering that
doesn't induce epileptic attacks... This "1.0.0" envy24control will be
able to do that, and the lower resource usage will help save the
planet too!
How the heck did you manage the slider markings, after
I posted I thought it
was impossible to satisfy, especially with different cards ?
I hopefully did the same thing as with 'alsamixer' which gives dB
readings for all sliders -- but I'd love to have this tested with
different cards to find out if there's problems. In particular M-Audio
Delta 1010's, M-Audio Audiophile 2496, TerraTec EWS 88MT, TerraTec EWS
88D, TerraTec Phase 88, Hoontech SoundTrack DSP 24.
http://nielsmayer.com/envy24control/envy24control-0.6-to-1.0.patch
(patch to 'envy24control' from GIT trunk of alsa-tools)
http://nielsmayer.com/envy24control/envy24control-1.0.tar.gz
(full directory, just follow README directions to build/install)
http://nielsmayer.com/envy24control/envy24control-1.0-fc12-x86_64.tar.gz
(x86_64 binary that should work on fedora12 and equivalent OpenSuse release)
http://nielsmayer.com/envy24control/envy24control-1.0.README
(summary of changes from 0.6.0 to 1.0.0)
-- Niels
http://nielsmayer.com
5:53 a.m.
On July 24, 2010 03:54:19 pm Tim E. Real wrote:
It turns out that Flash wants to play everything
at a 48000Hz sample rate.
Since my audio card is an Envy24 based card,
it always boots up in 44100Hz sample rate mode.
So now, before I play Flash videos, I must open the
envy24control mixer and set the sample rate to 48000Hz.
It works every time now !
Can someone explain the process of how Flash plays audio,
and how to force it to use 44100Hz?
Good grief, I am not playing with a 'full deck' today !
I turned off the 'lock' control in envy24control and now Flash can
set the rate to 48000Hz.
Yipeee ! Sorry for the noise about that bit.
Tim.
4:40 p.m.
On Sat, Jul 24, 2010 at 8:41 PM, Tim E. Real <termtech(a)rogers.com> wrote:
I turned off the 'lock' control in
envy24control and now Flash can
set the rate to 48000Hz.
I forgot to mention the "Multi Track Rate Locking" and "Multi Track
Rate Reset" issues... Or the fact that sometimes you have to switch
the clock rate around a few times manually to force it to reset when
externally sync'd via SPDIF...
Part of the problem is that the "Locked" and "Reset" are badly named
in envy24control.
In a screenshot I didn't include, one of the minor changes I made is
to use the standard ALSA names,
so at least the poor user faced with weird lockups can get some
meaningful google searches back:
http://www.google.com/search?hl=en&q=ice1712+ice1724+multi+track+rate+l…
or
http://www.google.com/search?hl=en&q=ice1712+ice1724+multi+track+rate+r…
.......................
@@ -667,7 +700,7 @@ static void create_rate_state(GtkWidget *box)
gtk_container_add(GTK_CONTAINER(frame), hbox);
gtk_container_set_border_width(GTK_CONTAINER(hbox), 6);
- check = gtk_check_button_new_with_label("Locked");
+ check = gtk_check_button_new_with_label("Multi Track\nRate Locking");
hw_rate_locking_check = check;
gtk_widget_show(check);
gtk_box_pack_start(GTK_BOX(hbox), check, FALSE, FALSE, 0);
@@ -676,7 +709,7 @@ static void create_rate_state(GtkWidget *box)
(gpointer)"locked");
- check = gtk_check_button_new_with_label("Reset");
+ check = gtk_check_button_new_with_label("Multi Track\nRate Reset");
hw_rate_reset_check = check;
gtk_widget_show(check);
gtk_box_pack_start(GTK_BOX(hbox), check, FALSE, FALSE, 0);
..................
Niels
http://nielsmayer.com
PS: Now playing, and generally excellent once you get past the talking
(and amarok's or m4a's refusal to let me fast-forward past it...) It
just suckers you in with that big fat "supersaw" (?) synth line at the
beginning of "Subway to Cologne" I swear..... (( requesting equivalent
yoshimi patch, plz! ))
http://www.whatpeopleplay.com/tracks/podcasts/27.m4a
That's STORY #27
DJ Mix by ??? including interview with the mysterious A&R of the
secret STORY label
Tracklisting:
1. story01-Subway To Cologne
2. story02 - deepcut59
3. story03-whobadu
4. Juju & Jordash - Hired guns - downbeat
5. Kai Alce - ??? - real soon
6. San Soda - Ode aan de Nacht - we play house
7. stl - vintage hunter - something
8. Theo Parrish - I cant take it - sound signature
9. the mole - The Date - spectral
10. Trickski - ??? - still love 4 music
11. Dreevsn - ??? - acido
12. even tuell - lunch time with lowtec - out to lunch
13. Levon Vincent - Six figures - novel sound
14. Marcellus Pittman - Skylark - fxhe
15. Oni Ayhun - ooar003-b - oar
9:43 p.m.
On July 25, 2010 10:40:22 am you wrote:
On Sat, Jul 24, 2010 at 8:41 PM, Tim E. Real
<termtech(a)rogers.com> wrote:
Yeah, if someone like me who's studied the code, can forget
(or never learned?) what that lock was for, imagine the
trouble others have. To be fair, I never RTFM, hmm, is there a manual?
I would prefer tooltips on some of those controls, although maybe that's
not the right place to say "Leave lock off for normal usage" or something...
Trouble is, I think it boots up like that, with the lock on.
My friend who's setting up a studio and who's never tried linux before,
has a Delta1010LT card (like me), and took the plunge and installed Ubuntu.
His first phone call to me was "Uh, Tim, no audio !"
Good thing he's got me to help, er, or hinder ...
Thanks for the amazing work on this. Will test and report.
Tim.
I turned off the 'lock' control in
envy24control and now Flash can
set the rate to 48000Hz.
I forgot to mention the "Multi Track Rate Locking" and "Multi Track
Rate Reset" issues... Or the fact that sometimes you have to switch
the clock rate around a few times manually to force it to reset when
externally sync'd via SPDIF...
Part of the problem is that the "Locked" and "Reset" are badly named
in envy24control.
In a screenshot I didn't include, one of the minor changes I made is
to use the standard ALSA names,
so at least the poor user faced with weird lockups can get some
meaningful google searches back:
http://www.google.com/search?hl=en&q=ice1712+ice1724+multi+track+rate+l…
ng or
http://www.google.com/search?hl=en&q=ice1712+ice1724+multi+track+rate+r…
.......................
@@ -667,7 +700,7 @@ static void create_rate_state(GtkWidget *box)
gtk_container_add(GTK_CONTAINER(frame), hbox);
gtk_container_set_border_width(GTK_CONTAINER(hbox), 6);
- check = gtk_check_button_new_with_label("Locked");
+ check = gtk_check_button_new_with_label("Multi Track\nRate Locking");
hw_rate_locking_check = check;
gtk_widget_show(check);
gtk_box_pack_start(GTK_BOX(hbox), check, FALSE, FALSE, 0);
@@ -676,7 +709,7 @@ static void create_rate_state(GtkWidget *box)
(gpointer)"locked");
- check = gtk_check_button_new_with_label("Reset");
+ check = gtk_check_button_new_with_label("Multi Track\nRate Reset");
hw_rate_reset_check = check;
gtk_widget_show(check);
gtk_box_pack_start(GTK_BOX(hbox), check, FALSE, FALSE, 0);
..................
Niels
http://nielsmayer.com
PS: Now playing, and generally excellent once you get past the talking
(and amarok's or m4a's refusal to let me fast-forward past it...) It
just suckers you in with that big fat "supersaw" (?) synth line at the
beginning of "Subway to Cologne" I swear..... (( requesting equivalent
yoshimi patch, plz! ))
http://www.whatpeopleplay.com/tracks/podcasts/27.m4a
That's STORY #27
DJ Mix by ??? including interview with the mysterious A&R of the
secret STORY label
Tracklisting:
1. story01-Subway To Cologne
2. story02 - deepcut59
3. story03-whobadu
4. Juju & Jordash - Hired guns - downbeat
5. Kai Alce - ??? - real soon
6. San Soda - Ode aan de Nacht - we play house
7. stl - vintage hunter - something
8. Theo Parrish - I cant take it - sound signature
9. the mole - The Date - spectral
10. Trickski - ??? - still love 4 music
11. Dreevsn - ??? - acido
12. even tuell - lunch time with lowtec - out to lunch
13. Levon Vincent - Six figures - novel sound
14. Marcellus Pittman - Skylark - fxhe
15. Oni Ayhun - ooar003-b - oar
5327
days inactive
5328
days old
linux-audio-dev@lists.linuxaudio.org
7 comments
2 participants
participants (2)
-
Niels Mayer -
Tim E. Real