Re: [Asterisk-Users] Asterisk Native Sound Distortion (ulaw)
shadowym wrote:
I found that the distortion was consistent. In other words it happened in
the same way at the same time in a particular file. I suspect it has
something to do with how Asterisk plays it back and not any sort of
hardware/IDE/interrupt issue. Kris, the developer of Astlinux didn't seem
to have any ideas why it would not work as well on Asterisk either.
If the distortion is consistant as you say, then you are probably seeing
the same problem I found a workaround for.
I was disappointed in the sound quality of the gsm files, so I was happy
to find the Native Sounds files. However, I then ran into the clicks and
pops when playing them. Reading some of the earlier comments in this
discussion someone mentioned an issue with Asterisk not padding files to
even 20ms increments when playing them. So, although that may be a bug
in Asterisk, I thought I would see if that was the problem by writing a
quick C program to pad all my ulaw files to multiples of 160 bytes.
Voila, all clicks and pops were gone. So, I don't know if that is the
only issue, and perhaps there are other problems people are having, but
padding the files fixed the issue for me. Obviously this should be fixed
in Asterisk.
If anyone else wants to try this experiment I've enclosed the simple C
program I wrote below. If you compile it and call it padulaw here is how
I fixed all the files:
find /var/lib/asterisk/sounds -type f -name '*.ulaw' | xargs padulaw
This program could be easily modified to pad .sln files to a multiple of
320 bytes (the files would be padded with 0x rather than 0xff).
John
#include stdio.h
#include fcntl.h
#include sys/stat.h
#include sys/types.h
#define ULAW_SILENCE 0xff
#define MS20_BYTES 160
unsigned char silence[MS20_BYTES];
void pad_file(char *);
main(int argc, char **argv)
{
int i;
int nfiles;
if (argc 2) {
fprintf(stderr,Usage: %s file name ...\n,argv[0]);
exit(1);
}
nfiles = argc - 1;
for (i = 0; i nfiles; i++) {
pad_file(argv[i+1]);
}
exit(0);
}
void
pad_file(char *fname)
{
int fd;
int i;
struct stat sbuf;
int filesize;
int remainder;
int nwrite;
fd = open(fname,O_WRONLY|O_APPEND);
if (fd 0) {
fprintf(stderr,Could not open %s for writing.\n,fname);
return;
}
if (fstat(fd,sbuf) != 0) {
fprintf(stderr,Could not stat file %s.\n,fname);
return;
}
filesize = (int) sbuf.st_size;
remainder = filesize % MS20_BYTES;
if (remainder == 0) {
close(fd);
return;
}
nwrite = MS20_BYTES - remainder;
for (i = 0; i nwrite; i++)
silence[i] = (unsigned char)ULAW_SILENCE;
if (write(fd,(void *)silence,nwrite) != nwrite) {
fprintf(stderr,Write Failure on file %s\n,fname);
return;
}
close(fd);
return;
}
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Re: [Asterisk-Users] Asterisk Native Sound Distortion (ulaw)
On 9/12/06, John Marvin [EMAIL PROTECTED] wrote: shadowym wrote: [snip] Asterisk not padding files to even 20ms increments when playing them. So, although that may be a bug in Asterisk, I thought I would see if that was the problem by writing a quick C program to pad all my ulaw files to multiples of 160 bytes. Voila, all clicks and pops were gone. So, I don't know if that is the only issue, and perhaps there are other problems people are having, but padding the files fixed the issue for me. Obviously this should be fixed in Asterisk. If anyone else wants to try this experiment I've enclosed the simple C program I wrote below. If you compile it and call it padulaw here is how I fixed all the files: find /var/lib/asterisk/sounds -type f -name '*.ulaw' | xargs padulaw This program could be easily modified to pad .sln files to a multiple of 320 bytes (the files would be padded with 0x rather than 0xff). John [snip] I don't suppose you know what the silence padding bytes would be for ALAW? Thanks, Steve ___ --Bandwidth and Colocation provided by Easynews.com -- asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
Re: [Asterisk-Users] Asterisk Native Sound Distortion (ulaw)
On 9/12/06, Steve Davies [EMAIL PROTECTED] wrote: I don't suppose you know what the silence padding bytes would be for ALAW? Found it... It is 0x55. Thanks for the program :) Steve ___ --Bandwidth and Colocation provided by Easynews.com -- asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
Re: [Asterisk-Users] Asterisk Native Sound Distortion (ulaw)
On Sat, Jul 01, 2006 at 01:29:30PM +0200, Paul Hewlett wrote: Maybe on other distros the sound files are being read from an IDe disk and the interrupts generated are distorting the sound - on astlinux the soundfiles are in a memory filesystem - no interrupts - no distortion ? Bigger systems have large buffers. An hourly cron job to can the sound files you normally use to /dev/null? -- Tzafrir Cohen sip:[EMAIL PROTECTED] icq#16849755 iax:[EMAIL PROTECTED] +972-50-7952406 jabber:[EMAIL PROTECTED] [EMAIL PROTECTED] http://www.xorcom.com ___ --Bandwidth and Colocation provided by Easynews.com -- asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
RE: [Asterisk-Users] Asterisk Native Sound Distortion (ulaw)
I have the same problem and so do many others. I filed a bug report but it was cancelled because the developers did not feel it was a problem with Asterisk. Perhaps they just don't want to support native sounds. If they did it would technically be considered a problem with Asterisk. So basically there does not appear to be any interest in fixing this. I found that the distortion was consistent. In other words it happened in the same way at the same time in a particular file. I suspect it has something to do with how Asterisk plays it back and not any sort of hardware/IDE/interrupt issue. Kris, the developer of Astlinux didn't seem to have any ideas why it would not work as well on Asterisk either. -Original Message- From: Tzafrir Cohen [mailto:[EMAIL PROTECTED] Sent: Sunday, September 10, 2006 11:20 PM To: asterisk-users@lists.digium.com Subject: Re: [Asterisk-Users] Asterisk Native Sound Distortion (ulaw) On Sat, Jul 01, 2006 at 01:29:30PM +0200, Paul Hewlett wrote: Maybe on other distros the sound files are being read from an IDe disk and the interrupts generated are distorting the sound - on astlinux the soundfiles are in a memory filesystem - no interrupts - no distortion ? Bigger systems have large buffers. An hourly cron job to can the sound files you normally use to /dev/null? -- Tzafrir Cohen sip:[EMAIL PROTECTED] icq#16849755 iax:[EMAIL PROTECTED] +972-50-7952406 jabber:[EMAIL PROTECTED] [EMAIL PROTECTED] http://www.xorcom.com ___ --Bandwidth and Colocation provided by Easynews.com -- asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
Re: [Asterisk-Users] Asterisk Native Sound Distortion (ulaw)
Tzafrir Cohen wrote: On Sat, Jul 01, 2006 at 01:29:30PM +0200, Paul Hewlett wrote: Maybe on other distros the sound files are being read from an IDe disk and the interrupts generated are distorting the sound - on astlinux the soundfiles are in a memory filesystem - no interrupts - no distortion ? Bigger systems have large buffers. An hourly cron job to can the sound files you normally use to /dev/null? Although tmpfs is used extensively in AstLinux, all of the sound prompts are stored and read from disk. This issue has come up several times, and I have no idea why they sound so much better in AstLinux. Don't get me wrong - I'm glad they do, but they should work equally well for all users of Asterisk, not just those that use AstLinux! Actually, now that I think about it, AstLinux does have one crucial difference. By default, DMA for IDE transfers are disabled (better compatibility with compact flash - rather safe than sorry)... I should try to enable DMA on a system that supports it and see what happens. -- Kristian Kielhofner ___ --Bandwidth and Colocation provided by Easynews.com -- asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
Re: [Asterisk-Users] Asterisk Native Sound Distortion (ulaw)
On Thursday 29 June 2006 18:07, Kristian Kielhofner wrote: shadowym wrote: I too have noticed problems with Asterisk native sounds using ulaw on Asterisk 1.2.9.1. Don't know about other versions but it seems to work quite well in Astlinux 0.40. In theory, since I am using ulaw for SIP there is no transcoding so it is a more efficient use of CPU resources and it should sound much better in general. It does sound better except for the frequent cracles, pops, and momentary dropouts which makes it much more objectionable to listen to compared to the standard GSM files. Is there a bug report on this yet? shadowym, While I haven't noticed this myself, many people have pointed this out. I can assure you that the prompts in AstLinux 0.4 are the same native prompts provided on astlinux.org. I don't know why they seem to sound so much better in AstLinux than with standard Asterisk installs, but as I said many people have noticed this. In theory, the native sounds should sound much better no matter how you play them back. Interesting... -- Kristian Kielhofner Maybe on other distros the sound files are being read from an IDe disk and the interrupts generated are distorting the sound - on astlinux the soundfiles are in a memory filesystem - no interrupts - no distortion ? Paul ___ --Bandwidth and Colocation provided by Easynews.com -- Asterisk-Users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users ___ --Bandwidth and Colocation provided by Easynews.com -- Asterisk-Users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
[Asterisk-Users] Asterisk Native Sound Distortion (ulaw)
I too have noticed problems with Asterisk native sounds using ulaw on Asterisk 1.2.9.1. Don't know about other versions but it seems to work quite well in Astlinux 0.40. In theory, since I am using ulaw for SIP there is no transcoding so it is a more efficient use of CPU resources and it should sound much better in general. It does sound better except for the frequent cracles, pops, and momentary dropouts which makes it much more objectionable to listen to compared to the standard GSM files. Is there a bug report on this yet? -Original Message- From: Tim Panton [mailto:[EMAIL PROTECTED] Sent: Thursday, June 29, 2006 2:04 AM To: Asterisk Users Mailing List - Non-Commercial Discussion Subject: Re: [Asterisk-Users] Standard Sound Files Distortion On 28 Jun 2006, at 19:50, Douglas Garstang wrote: -Original Message- From: Doug Lytle [mailto:[EMAIL PROTECTED] Sent: Wednesday, June 28, 2006 12:31 PM To: Asterisk Users Mailing List - Non-Commercial Discussion Subject: Re: [Asterisk-Users] Standard Sound Files Distortion Douglas Garstang wrote: I've been noticing lately what seems to be some distortian in the standard asterisk sound files, used for voicemail. These files are stored on the local Asterisk system. When Asterisk plays them, I can hear some cracles and pops. I'd never noticed these until recently. What I've learned from reading the list, is it usually is a sign of shared IRQs. Just a thought. Thanks for the reply. I just worked out what it was. I had ulaw copies of all the sound files in the digits/ directory. For some reason, the ulaw files either had the cracks and pops in the recordings, or when asterisk played the ulaw files, it generated the cracks and pops. I've noticed something that may (or may not) be related. If you have a sound file that isn't an exact multiple of 20ms long, then asterisk 1.2.9.1 (don't know about other versions - yet) sends out a 'partial' packet with the remaining data in it. For ulaw, the data would normally be 160 bytes, but a few (the last?) packet(s) might be 54 bytes (or whatever). This confuses my softphone. Do we think this is correct behavior ? Shouldn't asterisk pad the sound out to 20ms? Note - this never occurs with GSM data, like the 'standard' voice files, as gsm is always a multiple of 20ms long. T. Tim Panton [EMAIL PROTECTED] ___ --Bandwidth and Colocation provided by Easynews.com -- Asterisk-Users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
Re: [Asterisk-Users] Asterisk Native Sound Distortion (ulaw)
shadowym wrote: I too have noticed problems with Asterisk native sounds using ulaw on Asterisk 1.2.9.1. Don't know about other versions but it seems to work quite well in Astlinux 0.40. In theory, since I am using ulaw for SIP there is no transcoding so it is a more efficient use of CPU resources and it should sound much better in general. It does sound better except for the frequent cracles, pops, and momentary dropouts which makes it much more objectionable to listen to compared to the standard GSM files. Is there a bug report on this yet? shadowym, While I haven't noticed this myself, many people have pointed this out. I can assure you that the prompts in AstLinux 0.4 are the same native prompts provided on astlinux.org. I don't know why they seem to sound so much better in AstLinux than with standard Asterisk installs, but as I said many people have noticed this. In theory, the native sounds should sound much better no matter how you play them back. Interesting... -- Kristian Kielhofner ___ --Bandwidth and Colocation provided by Easynews.com -- Asterisk-Users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
