[Freeswitch-users] Choosing a Codec.

[Vinuth Madinur]

Hi,

I am playing a file to a landline number.

the format of the file is as follows:

[root at static-host var]# file message.wav
message.wav: RIFF (little-endian) data, WAVE audio, ITU G.711 mu-law, mono
8000 Hz

In my vars.xml file I have used the following codec prefs:

<X-PRE-PROCESS cmd="set" data="global_codec_prefs=PCMU,PCMA,GSM"/>
<X-PRE-PROCESS cmd="set" data="outbound_codec_prefs=PCMU,G722,GSM"/>

However, when freeswitch plays it, it always chooses the L16 at 8000hz codec.
I'm not understanding why this is so.

EXECUTE sofia/external/5135692990 at 208.78.161.197 playback(/var/message.wav)
2009-12-22 17:16:57.357048 [DEBUG] switch_ivr_play_say.c:1135 Codec
Activated L16 at 8000hz 1 channels 20ms
2009-12-22 17:17:30.777182 [DEBUG] switch_ivr_play_say.c:1429 done playing
file


My basic intent is to avoid on-the-fly transcoding, while having a high
quality audio playing on PSTN.

Have I configured it wrong or does this transcoding always happen?

Thanks,
Vinuth.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.freeswitch.org/pipermail/freeswitch-users/attachments/20091223/3d272e5d/attachment.html

[Brian West]

Why? You don't have to avoid it... why bother?

/b

My basic intent is to avoid on-the-fly transcoding, while having a high quality audio playing on PSTN.

[Vinuth Madinur]

The audio quality is a lot different when it plays on the landline. And the
quality degrades a bit when the message played is lengthy >30s. So I thought
it would be better if I have the file in mu-law and play it as is..

Thanks,
Vinuth.

Post by Brian West
Why? You don't have to avoid it... why bother?
/b

Post by Vinuth Madinur
My basic intent is to avoid on-the-fly transcoding, while having a high

quality audio playing on PSTN.
_______________________________________________
FreeSWITCH-users mailing list
FreeSWITCH-users at lists.freeswitch.org
http://lists.freeswitch.org/mailman/listinfo/freeswitch-users
UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users
http://www.freeswitch.org

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.freeswitch.org/pipermail/freeswitch-users/attachments/20091223/20e9b85f/attachment.html

[Brian West]

If its degrading like that you have bigger issues... the sound files played from wav files vs raw PCM files is NO different on a land line and I speak from very many years of experience... your wav files are ulaw in wav containers thus will never play native which might just be part of your problem. You would have to have raw headerless data in a .PCMU file for it to play native.

Can you elaborate on your setup a bit more?

/b

The audio quality is a lot different when it plays on the landline. And the quality degrades a bit when the message played is lengthy >30s. So I thought it would be better if I have the file in mu-law and play it as is..
Thanks,
Vinuth.

[David Knell]

On the other hand, a u-law WAV turned into L16 and then back to u-law to
be sent down the line shouldn't suffer any alteration at all - if it
does, the there's something wrong with the translation.

The quality dropping over time is almost certainly down to something
else. Vinuth -can you get a recording to compare with the original?

--Dave

Post by Brian West
If its degrading like that you have bigger issues... the sound files played from wav files vs raw PCM files is NO different on a land line and I speak from very many years of experience... your wav files are ulaw in wav containers thus will never play native which might just be part of your problem. You would have to have raw headerless data in a .PCMU file for it to play native.
Can you elaborate on your setup a bit more?
/b

The audio quality is a lot different when it plays on the landline. And the quality degrades a bit when the message played is lengthy >30s. So I thought it would be better if I have the file in mu-law and play it as is..
Thanks,
Vinuth.

_______________________________________________
FreeSWITCH-users mailing list
FreeSWITCH-users at lists.freeswitch.org
http://lists.freeswitch.org/mailman/listinfo/freeswitch-users
UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users
http://www.freeswitch.org

[EdPimentl]

Have you considered GIPS http://www.gipscorp.com/products/overview.php ?
-E
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.freeswitch.org/pipermail/freeswitch-users/attachments/20091222/99a38e79/attachment.html

[Michael Jerris]

That being said, ulaw l16 alaw will cause degredation and any other
modifications such as volume adjustment in this path will make it
worse. Tha being said that does not sound like what you are
experiencing

Mike

Post by David Knell
On the other hand, a u-law WAV turned into L16 and then back to u-
law to
be sent down the line shouldn't suffer any alteration at all - if it
does, the there's something wrong with the translation.
The quality dropping over time is almost certainly down to something
else. Vinuth -can you get a recording to compare with the original?
--Dave

Post by Brian West
If its degrading like that you have bigger issues... the sound
files played from wav files vs raw PCM files is NO different on a
land line and I speak from very many years of experience... your
wav files are ulaw in wav containers thus will never play native
which might just be part of your problem. You would have to have
raw headerless data in a .PCMU file for it to play native.
Can you elaborate on your setup a bit more?
/b

Post by Vinuth Madinur
The audio quality is a lot different when it plays on the
landline. And the quality degrades a bit when the message played
is lengthy >30s. So I thought it would be better if I have the
file in mu-law and play it as is..
Thanks,
Vinuth.

_______________________________________________
FreeSWITCH-users mailing list
FreeSWITCH-users at lists.freeswitch.org
http://lists.freeswitch.org/mailman/listinfo/freeswitch-users
UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-
users
http://www.freeswitch.org

_______________________________________________
FreeSWITCH-users mailing list
FreeSWITCH-users at lists.freeswitch.org
http://lists.freeswitch.org/mailman/listinfo/freeswitch-users
UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-
users
http://www.freeswitch.org

[David Knell]

Post by Michael Jerris
That being said, ulaw l16 alaw will cause degredation and any other
modifications such as volume adjustment in this path will make it
worse.

Indeed. Storing prompts
as 8k, 16-bit WAVs
makes a lot of sense.

[I am inordinately pleased with the above]

--Dave

[Vinuth Madinur]

Post by David Knell

Post by Michael Jerris
That being said, ulaw l16 alaw will cause degredation and any other
modifications such as volume adjustment in this path will make it
worse.

Indeed. Storing prompts
as 8k, 16-bit WAVs
makes a lot of sense.
[I am inordinately pleased with the above]
--Dave

Thanks, will try and get back.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.freeswitch.org/pipermail/freeswitch-users/attachments/20091223/9a4ae9f3/attachment.html

[Vinuth Madinur]

Post by David Knell

Post by Michael Jerris
That being said, ulaw l16 alaw will cause degredation and any other
modifications such as volume adjustment in this path will make it
worse.

Indeed. Storing prompts
as 8k, 16-bit WAVs
makes a lot of sense.
[I am inordinately pleased with the above]
--Dave

Thanks, will try and get back.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.freeswitch.org/pipermail/freeswitch-users/attachments/20091223/9a4ae9f3/attachment-0002.html

[David Knell]

Post by Michael Jerris
That being said, ulaw l16 alaw will cause degredation and any other
modifications such as volume adjustment in this path will make it
worse.

Indeed. Storing prompts
as 8k, 16-bit WAVs
makes a lot of sense.

[I am inordinately pleased with the above]

--Dave

[Steve Underwood]

Post by David Knell
On the other hand, a u-law WAV turned into L16 and then back to u-law to
be sent down the line shouldn't suffer any alteration at all - if it
does, the there's something wrong with the translation.
The quality dropping over time is almost certainly down to something
else. Vinuth -can you get a recording to compare with the original?

A linear->ulaw->linear->ulaw->linear->ulaw chain *should* only loose
quality on the first cycle. However:
- Many ulaw implementation are buggy, because they are based on the
same broken Sun code. People are gradually waking up and fixing this.
The broken
implementations can loose considerable quality on each cycle.
- Anywhere people fiddle with gains, you will loose quality on each
cycle.

Steve

[EdPimentl]

Have you considered GIPS http://www.gipscorp.com/products/overview.php ?
-E
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.freeswitch.org/pipermail/freeswitch-users/attachments/20091222/99a38e79/attachment-0002.html

[Michael Jerris]

That being said, ulaw l16 alaw will cause degredation and any other
modifications such as volume adjustment in this path will make it
worse. Tha being said that does not sound like what you are
experiencing

Mike

Post by David Knell
On the other hand, a u-law WAV turned into L16 and then back to u-
law to
be sent down the line shouldn't suffer any alteration at all - if it
does, the there's something wrong with the translation.
The quality dropping over time is almost certainly down to something
else. Vinuth -can you get a recording to compare with the original?
--Dave

Post by Brian West
If its degrading like that you have bigger issues... the sound
files played from wav files vs raw PCM files is NO different on a
land line and I speak from very many years of experience... your
wav files are ulaw in wav containers thus will never play native
which might just be part of your problem. You would have to have
raw headerless data in a .PCMU file for it to play native.
Can you elaborate on your setup a bit more?
/b

Post by Vinuth Madinur
The audio quality is a lot different when it plays on the
landline. And the quality degrades a bit when the message played
is lengthy >30s. So I thought it would be better if I have the
file in mu-law and play it as is..
Thanks,
Vinuth.

_______________________________________________
FreeSWITCH-users mailing list
FreeSWITCH-users at lists.freeswitch.org
http://lists.freeswitch.org/mailman/listinfo/freeswitch-users
UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-
users
http://www.freeswitch.org

_______________________________________________
FreeSWITCH-users mailing list
FreeSWITCH-users at lists.freeswitch.org
http://lists.freeswitch.org/mailman/listinfo/freeswitch-users
UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-
users
http://www.freeswitch.org

[Steve Underwood]

Post by David Knell
On the other hand, a u-law WAV turned into L16 and then back to u-law to
be sent down the line shouldn't suffer any alteration at all - if it
does, the there's something wrong with the translation.
The quality dropping over time is almost certainly down to something
else. Vinuth -can you get a recording to compare with the original?

A linear->ulaw->linear->ulaw->linear->ulaw chain *should* only loose
quality on the first cycle. However:
- Many ulaw implementation are buggy, because they are based on the
same broken Sun code. People are gradually waking up and fixing this.
The broken
implementations can loose considerable quality on each cycle.
- Anywhere people fiddle with gains, you will loose quality on each
cycle.

Steve

[Vinuth Madinur]

My setup is as follows:

FreeSWITCH -> SIP Trunk -> PSTN.

From freeswitch, I'm making outbound calls using event socket via the

"external" profile. Except for the ext_rtp_ip and ext_sip_ip, everything is
default settings. Using "playback" application, I'm playing a mu-law audio.
I'm also starting the "vmd" application, so that I can replay the message on
beep.

Thanks for your suggestion on native format. I'll try it.

Thanks,
Vinuth.

If its degrading like that you have bigger issues... the sound files played
from wav files vs raw PCM files is NO different on a land line and I speak
from very many years of experience... your wav files are ulaw in wav
containers thus will never play native which might just be part of your
problem. You would have to have raw headerless data in a .PCMU file for it
to play native.
Can you elaborate on your setup a bit more?
/b

Post by Vinuth Madinur
The audio quality is a lot different when it plays on the landline. And

the quality degrades a bit when the message played is lengthy >30s. So I
thought it would be better if I have the file in mu-law and play it as is..

Post by Vinuth Madinur
Thanks,
Vinuth.

_______________________________________________
FreeSWITCH-users mailing list
FreeSWITCH-users at lists.freeswitch.org
http://lists.freeswitch.org/mailman/listinfo/freeswitch-users
UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users
http://www.freeswitch.org

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.freeswitch.org/pipermail/freeswitch-users/attachments/20091223/9ee6022d/attachment.html

[Brian West]

VMD will force a transcode anyway too.

/b

Post by Vinuth Madinur
FreeSWITCH -> SIP Trunk -> PSTN.
From freeswitch, I'm making outbound calls using event socket via the "external" profile. Except for the ext_rtp_ip and ext_sip_ip, everything is default settings. Using "playback" application, I'm playing a mu-law audio. I'm also starting the "vmd" application, so that I can replay the message on beep.
Thanks for your suggestion on native format. I'll try it.
Thanks,
Vinuth.

[Anthony Minessale]

It's more than highly likely you have some other problem like jitter or a
bad network connection.
Not many people would be able to tell the difference between the sound of an
8k PCM file and the same file encoded to G711 just by listening to it unless
there was a severe problem somewhere. Since you are behind NAT you are even
more likely to experience drops etc.

Record your files as 8k raw 16 bit PCM to get the best out of the file
playback in FS and look elsewhere for your audio issues.

You can always make sure you are using the latest build of FS to rule out
any temporary issues in the code.

Post by Brian West
VMD will force a transcode anyway too.
/b

Post by Vinuth Madinur
FreeSWITCH -> SIP Trunk -> PSTN.
From freeswitch, I'm making outbound calls using event socket via the

"external" profile. Except for the ext_rtp_ip and ext_sip_ip, everything is
default settings. Using "playback" application, I'm playing a mu-law audio.
I'm also starting the "vmd" application, so that I can replay the message on
beep.

Post by Vinuth Madinur
Thanks for your suggestion on native format. I'll try it.
Thanks,
Vinuth.

_______________________________________________
FreeSWITCH-users mailing list
FreeSWITCH-users at lists.freeswitch.org
http://lists.freeswitch.org/mailman/listinfo/freeswitch-users
UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users
http://www.freeswitch.org

--
Anthony Minessale II

FreeSWITCH http://www.freeswitch.org/
ClueCon http://www.cluecon.com/
Twitter: http://twitter.com/FreeSWITCH_wire

AIM: anthm
MSN:anthony_minessale at hotmail.com <MSN%3Aanthony_minessale at hotmail.com>
GTALK/JABBER/PAYPAL:anthony.minessale at gmail.com<PAYPAL%3Aanthony.minessale at gmail.com>
IRC: irc.freenode.net #freeswitch

FreeSWITCH Developer Conference
sip:888 at conference.freeswitch.org <sip%3A888 at conference.freeswitch.org>
iax:guest at conference.freeswitch.org/888
googletalk:conf+888 at conference.freeswitch.org<googletalk%3Aconf%2B888 at conference.freeswitch.org>
pstn:[phone]
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.freeswitch.org/pipermail/freeswitch-users/attachments/20091223/5f0a921c/attachment.html

[Anthony Minessale]

It's more than highly likely you have some other problem like jitter or a
bad network connection.
Not many people would be able to tell the difference between the sound of an
8k PCM file and the same file encoded to G711 just by listening to it unless
there was a severe problem somewhere. Since you are behind NAT you are even
more likely to experience drops etc.

Record your files as 8k raw 16 bit PCM to get the best out of the file
playback in FS and look elsewhere for your audio issues.

You can always make sure you are using the latest build of FS to rule out
any temporary issues in the code.

Post by Brian West
VMD will force a transcode anyway too.
/b

Post by Vinuth Madinur
FreeSWITCH -> SIP Trunk -> PSTN.
From freeswitch, I'm making outbound calls using event socket via the

"external" profile. Except for the ext_rtp_ip and ext_sip_ip, everything is
default settings. Using "playback" application, I'm playing a mu-law audio.
I'm also starting the "vmd" application, so that I can replay the message on
beep.

Post by Vinuth Madinur
Thanks for your suggestion on native format. I'll try it.
Thanks,
Vinuth.

_______________________________________________
FreeSWITCH-users mailing list
FreeSWITCH-users at lists.freeswitch.org
http://lists.freeswitch.org/mailman/listinfo/freeswitch-users
UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users
http://www.freeswitch.org

--
Anthony Minessale II

FreeSWITCH http://www.freeswitch.org/
ClueCon http://www.cluecon.com/
Twitter: http://twitter.com/FreeSWITCH_wire

AIM: anthm
MSN:anthony_minessale at hotmail.com <MSN%3Aanthony_minessale at hotmail.com>
GTALK/JABBER/PAYPAL:anthony.minessale at gmail.com<PAYPAL%3Aanthony.minessale at gmail.com>
IRC: irc.freenode.net #freeswitch

FreeSWITCH Developer Conference
sip:888 at conference.freeswitch.org <sip%3A888 at conference.freeswitch.org>
iax:guest at conference.freeswitch.org/888
googletalk:conf+888 at conference.freeswitch.org<googletalk%3Aconf%2B888 at conference.freeswitch.org>
pstn:[phone]
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.freeswitch.org/pipermail/freeswitch-users/attachments/20091223/5f0a921c/attachment-0002.html

[Brian West]

VMD will force a transcode anyway too.

/b

Post by Vinuth Madinur
FreeSWITCH -> SIP Trunk -> PSTN.
From freeswitch, I'm making outbound calls using event socket via the "external" profile. Except for the ext_rtp_ip and ext_sip_ip, everything is default settings. Using "playback" application, I'm playing a mu-law audio. I'm also starting the "vmd" application, so that I can replay the message on beep.
Thanks for your suggestion on native format. I'll try it.
Thanks,
Vinuth.

[David Knell]

On the other hand, a u-law WAV turned into L16 and then back to u-law to
be sent down the line shouldn't suffer any alteration at all - if it
does, the there's something wrong with the translation.

The quality dropping over time is almost certainly down to something
else. Vinuth -can you get a recording to compare with the original?

--Dave

Post by Brian West
If its degrading like that you have bigger issues... the sound files played from wav files vs raw PCM files is NO different on a land line and I speak from very many years of experience... your wav files are ulaw in wav containers thus will never play native which might just be part of your problem. You would have to have raw headerless data in a .PCMU file for it to play native.
Can you elaborate on your setup a bit more?
/b

The audio quality is a lot different when it plays on the landline. And the quality degrades a bit when the message played is lengthy >30s. So I thought it would be better if I have the file in mu-law and play it as is..
Thanks,
Vinuth.

_______________________________________________
FreeSWITCH-users mailing list
FreeSWITCH-users at lists.freeswitch.org
http://lists.freeswitch.org/mailman/listinfo/freeswitch-users
UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users
http://www.freeswitch.org

[Vinuth Madinur]

My setup is as follows:

FreeSWITCH -> SIP Trunk -> PSTN.

From freeswitch, I'm making outbound calls using event socket via the

"external" profile. Except for the ext_rtp_ip and ext_sip_ip, everything is
default settings. Using "playback" application, I'm playing a mu-law audio.
I'm also starting the "vmd" application, so that I can replay the message on
beep.

Thanks for your suggestion on native format. I'll try it.

Thanks,
Vinuth.

If its degrading like that you have bigger issues... the sound files played
from wav files vs raw PCM files is NO different on a land line and I speak
from very many years of experience... your wav files are ulaw in wav
containers thus will never play native which might just be part of your
problem. You would have to have raw headerless data in a .PCMU file for it
to play native.
Can you elaborate on your setup a bit more?
/b

Post by Vinuth Madinur
The audio quality is a lot different when it plays on the landline. And

the quality degrades a bit when the message played is lengthy >30s. So I
thought it would be better if I have the file in mu-law and play it as is..

Post by Vinuth Madinur
Thanks,
Vinuth.

_______________________________________________
FreeSWITCH-users mailing list
FreeSWITCH-users at lists.freeswitch.org
http://lists.freeswitch.org/mailman/listinfo/freeswitch-users
UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users
http://www.freeswitch.org

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.freeswitch.org/pipermail/freeswitch-users/attachments/20091223/9ee6022d/attachment-0002.html

[Brian West]

If its degrading like that you have bigger issues... the sound files played from wav files vs raw PCM files is NO different on a land line and I speak from very many years of experience... your wav files are ulaw in wav containers thus will never play native which might just be part of your problem. You would have to have raw headerless data in a .PCMU file for it to play native.

Can you elaborate on your setup a bit more?

/b

The audio quality is a lot different when it plays on the landline. And the quality degrades a bit when the message played is lengthy >30s. So I thought it would be better if I have the file in mu-law and play it as is..
Thanks,
Vinuth.

[Vinuth Madinur]

The audio quality is a lot different when it plays on the landline. And the
quality degrades a bit when the message played is lengthy >30s. So I thought
it would be better if I have the file in mu-law and play it as is..

Thanks,
Vinuth.

Post by Brian West
Why? You don't have to avoid it... why bother?
/b

Post by Vinuth Madinur
My basic intent is to avoid on-the-fly transcoding, while having a high

quality audio playing on PSTN.
_______________________________________________
FreeSWITCH-users mailing list
FreeSWITCH-users at lists.freeswitch.org
http://lists.freeswitch.org/mailman/listinfo/freeswitch-users
UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users
http://www.freeswitch.org

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.freeswitch.org/pipermail/freeswitch-users/attachments/20091223/20e9b85f/attachment-0002.html

[Vinuth Madinur]

Hi,

I am playing a file to a landline number.

the format of the file is as follows:

[root at static-host var]# file message.wav
message.wav: RIFF (little-endian) data, WAVE audio, ITU G.711 mu-law, mono
8000 Hz

In my vars.xml file I have used the following codec prefs:

<X-PRE-PROCESS cmd="set" data="global_codec_prefs=PCMU,PCMA,GSM"/>
<X-PRE-PROCESS cmd="set" data="outbound_codec_prefs=PCMU,G722,GSM"/>

However, when freeswitch plays it, it always chooses the L16 at 8000hz codec.
I'm not understanding why this is so.

EXECUTE sofia/external/5135692990 at 208.78.161.197 playback(/var/message.wav)
2009-12-22 17:16:57.357048 [DEBUG] switch_ivr_play_say.c:1135 Codec
Activated L16 at 8000hz 1 channels 20ms
2009-12-22 17:17:30.777182 [DEBUG] switch_ivr_play_say.c:1429 done playing
file


My basic intent is to avoid on-the-fly transcoding, while having a high
quality audio playing on PSTN.

Have I configured it wrong or does this transcoding always happen?

Thanks,
Vinuth.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.freeswitch.org/pipermail/freeswitch-users/attachments/20091223/3d272e5d/attachment-0002.html

[Brian West]

Why? You don't have to avoid it... why bother?

/b

My basic intent is to avoid on-the-fly transcoding, while having a high quality audio playing on PSTN.