I have two questions about DVD-Audio
a)
can you help me to reading the DVD-Audio specification? They are not on
the net as far as I've seen. I want to do some modifications at
dvd-audio.sf.net .
b)
A GUI for authoring DVD-Audio is wanted.
Regarding this whole audio over Cat5 thread, do we actually understand what the objective is of this exercise / project? Is the original authors use of terminology such that we know what is actually supposed to be achieved?
When I first read this, I thought the idea was to produce some sort of network-transported audio stream, like that of a video stream, something which could be "listened to" by some network-connected client computer with its own audio output hardware. Since routers themselves have no speakers, I could not reach any other conclusion. Now it sounds more like a hack to get packets to somehow generate audio as a byproduct ... kind of like the audio version of streaming video via ASCII on a character terminal. Or a better analogy would be getting the old PC "speaker" to emit discernible sounds by sending digital data to it's IO port.
It reminds me of a story my uncle the television engineer told me about how there was a scrap pile of old bolts and cables lying on the floor in the corner of the antenna-transmitter shack of the VHF TV station where he was chief engineer for a number of years before he retired. One day, after replacing a couple of guy wire mounting brackets on the tower (a tower of about 1200'), he threw the scrap hardware on the junk pile in the shack. Suddenly, he could hear the audio signal for the station coming out of the junk pile. He tried to leave the pile undisturbed after that to preserve the effect, but eventually someone bumped or otherwise changed the pile and it stopped "working".
Sorry, I digress. So tell me again ... what is the real goal of this project?
- Doug H
Hi list.
I' m using alsa-lib v1.0.14rc2 on gentoo-linux (v2.6.20-gentoo-r8)
my soundcard is RME Hammerfall HDSP9632 (snd-hdsp driver)
i have been using it for a while - all fine
i only run a few applications for my sound experiments.
one of those is Snd (from CCRMA), it was okay until i have done a few
updates lately - kernel from 2.6.17 to 2.6.20 and alsa-lib as well.
i'm not sure about either of these but i check Snd src-tree and the
mailing list - nothing was changed ..
the error msg that i get is:
:(play)
;status of hw:0
hw_params status of hw:0
ACCESS: MMAP_NONINTERLEAVED RW_NONINTERLEAVED
FORMAT: S32_LE
SUBFORMAT: STD
SAMPLE_BITS: 32
FRAME_BITS: [128 384]
CHANNELS: [4 12]
RATE: [32000 192000]
PERIOD_TIME: (333 256000]
PERIOD_SIZE: [64 8192]
PERIOD_BYTES: [2560 393216]
PERIODS: 2
BUFFER_TIME: (666 512000]
BUFFER_SIZE: [128 16384]
BUFFER_BYTES: [2560 786432]
TICK_TIME: 1000
sw_params status of hw:0
start_mode: DATA
xrun_mode: STOP
tstamp_mode: NONE
period_step: 0
sleep_min: 0
avail_min: 0
xfer_align: 0
silence_threshold: 0
silence_size: 0
boundary: 0
;Invalid argument: hw:0: access type RW_INTERLEAVED not available
can't play : Invalid argument: hw:0: access type RW_INTERLEAVED not
available
#f
:
i had tried to modify audio.c in Snd's tree to use both ACCESS types
given above , but it didn't help - showed device is busy error instead.
i'm only studying C, so can't be sure ..
anyway here is a problem which i could not solve yet and haven't seen
anyone helpful around #alsa, neither i could google anything out.
for a ref.: Cmdist mailing list Cmdist(a)ccrma.stanford.edu http://ccrma-mail.stanford.edu/mailman/listinfo/cmdist
and our discussion is here:
http://ccrma-mail.stanford.edu/pipermail/cmdist/2007-July/004221.html
could anyone have a look at this at somepoint, please .
--
thank you,
Ilya. D
errordeveloper|*@*|gmail|*dot*|com
Hello,
Some interesting products based on Ethernet <-> audio applications may be
found here
http://audioscience.com/
Linux drivers ara available too.
Maybe this can help :)
vedran
Hi,
I am an undergrad student working on a project related to playing audio on a
Linksys WRT54GL Router through cat5 cable. I have the following setup.
A Linksys WRT54GL router with OpenWRT firmware on it. What i want to do is
to play some audio file (prefrably mp3 format), and stream the output over
Ethernet through CAT5 cables and convert it through a balun. I have broken
the process in following steps
1. Get the audio file and decode it (through libmad or a similar library)
2. Convert this to analog form
3. Send it over Ethernet
I understand the first part, and have already started the implementation,
but the other two steps are where i have problems.
To play it directly on a speaker i would need to convert it to Analog, but
how do make those analog signals travel over ethernet?
As you can i dont have much knowledge about audio programming, so i would
appreciate any help i could get on this mailing list.
Thanks.
Hallo list!
I am just thinking about the right strategy for denormal handling in a
floating point (single or double prec) audio application (and yes I
already read the docs of the different methods at musicdsp and so on ...)
Basically my question is, if it is enough to simply turn on the
Flush-to-zero and Denormals-are-zero mode and then compile everything
with -msse -mfpmath=sse ?
I know it won't run on older Pentium3,2 etc. - but for the machines
which support this feature, is this enough ?
Thanks for any hint,
LG
Georg
Hi!
I am trying to create a userspace driver with module uinput and I am
getting into trouble when I terminate the program that creates the
device. After a while the machine will crash ...
The object is to create a joystick device, and I might be missing some
important bits of documentation. So far I am not writing any data to the
interface, but js_demo will find it and open it, showing the expected
number of axis. The name of the interface looks like random though,
which worries me and gets me to suspect that something is wrong
Any idea why the machine is crashing or has a pointer to some example I
could study? As long as I just let the program run, there is no
problem ... Only on termination.
This is what I have gotten so far in the uinput department:
--8<-------------------------------------------------
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <signal.h>
#include <linux/input.h>
#include <linux/uinput.h>
int create_uinput() {
int fd = -1;
fd = open ("/dev/uinput", O_RDWR);
if (fd <= 0)
{
fprintf (stderr,"could not open uinput device\n");
exit(EXIT_FAILURE);
}
memset (&uinp, 0, sizeof (struct uinput_user_dev));
strncpy (uinp.name, "NoJoy!", 7); // FIXME!
uinp.id.version = 4;
uinp.id.bustype = BUS_USB;
ioctl (fd, UI_SET_EVBIT, EV_ABS);
ioctl (fd, UI_SET_EVBIT, EV_KEY);
ioctl (fd, UI_SET_ABSBIT, ABS_X);
ioctl (fd, UI_SET_ABSBIT, ABS_Y);
ioctl (fd, UI_SET_ABSBIT, ABS_Z);
ioctl (fd, UI_SET_ABSBIT, ABS_THROTTLE);
ioctl (fd, UI_SET_KEYBIT, BTN_TOP);
ioctl (fd, UI_SET_KEYBIT, BTN_TOP2);
ioctl (fd, UI_SET_KEYBIT, BTN_BASE);
ioctl (fd, UI_SET_KEYBIT, BTN_BASE2);
ioctl (fd, UI_SET_KEYBIT, BTN_BASE3);
ioctl (fd, UI_SET_KEYBIT, BTN_BASE4);
// Create device
write (fd, &uinp, sizeof (uinp));
if (ioctl (fd, UI_DEV_CREATE))
{
fprintf (stderr,"could not create uinput device.\n");
exit(EXIT_FAILURE);
}
sigset(SIGINT,destroy_uinput);
sigset(SIGTERM,destroy_uinput);
return fd;
}
void destroy_uinput()
{
fprintf(stderr,"NoJoy says: BYE!\n");
if(uinp_fd > 0)
{
ioctl (uinp_fd, UI_DEV_DESTROY);
close (uinp_fd);
}
exit(0);
}
--
Fons Adriaensen <fons(a)kokkinizita.net> sez:
>
> On Thu, Sep 27, 2007 at 09:03:32PM -0700, Maitland Vaughan-Turner wrote:
>
> > There was something like a 50% success rate in choosing the audio
> > source correctly.
>
> Which means it was just a random selection...
>
Obviously... (not that it proves anything either way)
I just thought it was an interesting coincidence that this article
appeared right on the heels of our discussion of the subject.
I *did* say maybe you're right and maybe it *is* all in my head.
hehe, no need to rub salt in it. :)
~Maitland
Hiho,
I am having a discussion on the supercollider front about what is the proper
way for dynamic linking.
as far as I know, you use ldconfig and have the library location that programs
dynamically link to defined in /etc/ld.so.conf
but what is supposed to happen if the user just installs the program to a
directory in his home directory?
how should the dynamic linking be defined?
esp. if the user does not have the root rights to change anything
in /etc/ld.so.conf or to run ldconfig.
I did not find anything quick on the net about this, so maybe one of you can
enlighten me what is the "proper" way of dealing with this.
sincerely,
Marije
Hallo!
> our experience with ardour has been that DC bias is measurably more
> effective at reducing CPU load than DAZ, FTZ or both combined. DAZ and
> FTZ do both help significantly, however.
One more question: is it not necessary to deactivate DAZ, FTZ again
after the application (or operation) ?
Or is this done automatically ?
(because I cannot see it e.g. in your ardour code)
Because e.g. in this document:
http://developer.apple.com/documentation/Performance/Conceptual/Accelerate_…
they set it back afterwards.
Thanks,
LG
Georg
