Hello,

I'm having a problem that I don't remember having some time ago (maybe
pre 5.10?). Using pvsfread to constantly loop a 1.5 seconds stereo pvx
file produces different sound each time it loops. I made this short
csd for testing purposes:




sr=48000
ksmps=64
nchnls=2

	instr 1
ipvxflen filelen "castanetas2b.pvx"
kposcps = (1/ipvxflen)
kphasor phasor kposcps
kpos = ipvxflen * kphasor


fsigInlB	pvsfread	kpos, "castanetas2b.pvx", 0
fsigInrB	pvsfread	kpos, "castanetas2b.pvx", 1

aoutL		pvsynth		fsigInlB
aoutR		pvsynth		fsigInrB

outc aoutL, aoutR
	endin



i1 0 20
e



The file "castanetas2b.pvx" can be found here in case it has something
to do with the problem (it was created using pvanal -n1024):
http://www.hcenteno.net/audio/castanetas2b.pvx

And this is how it sounds rendered in my system using Fedora 10 and
Csound 5.10: http://www.hcenteno.net/audio/castanetast_test.wav

Another odd thing is that there is a pause between each repetition
while there is no such thing when looping the original wav.

Thanks!

Hector

Which version are you using, CVS?
----- Original Message ----- 
From: "Hector Centeno" 
To: 
Sent: Sunday, May 24, 2009 7:32 PM
Subject: [Csnd] looping pvsfread sounds different each time


> Hello,
>
> I'm having a problem that I don't remember having some time ago (maybe
> pre 5.10?). Using pvsfread to constantly loop a 1.5 seconds stereo pvx
> file produces different sound each time it loops. I made this short
> csd for testing purposes:
>
> 
> 
>
> sr=48000
> ksmps=64
> nchnls=2
>
> instr 1
> ipvxflen filelen "castanetas2b.pvx"
> kposcps = (1/ipvxflen)
> kphasor phasor kposcps
> kpos = ipvxflen * kphasor
>
>
> fsigInlB pvsfread kpos, "castanetas2b.pvx", 0
> fsigInrB pvsfread kpos, "castanetas2b.pvx", 1
>
> aoutL pvsynth fsigInlB
> aoutR pvsynth fsigInrB
>
> outc aoutL, aoutR
> endin
>
> 
> 
> i1 0 20
> e
> 
> 
>
> The file "castanetas2b.pvx" can be found here in case it has something
> to do with the problem (it was created using pvanal -n1024):
> http://www.hcenteno.net/audio/castanetas2b.pvx
>
> And this is how it sounds rendered in my system using Fedora 10 and
> Csound 5.10: http://www.hcenteno.net/audio/castanetast_test.wav
>
> Another odd thing is that there is a pause between each repetition
> while there is no such thing when looping the original wav.
>
> Thanks!
>
> Hector
>
>
> Send bugs reports to this list.
> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe 
> csound" 

Thanks Victor,

I'm using the 5.10 rpms for FC10 from Koji  but had the same problem
with a CVS build from 2 or 3 months ago.

Hector

On Sunday, May 24, 2009, victor  wrote:
> Which version are you using, CVS?
> ----- Original Message ----- From: "Hector Centeno" 
> To: 
> Sent: Sunday, May 24, 2009 7:32 PM
> Subject: [Csnd] looping pvsfread sounds different each time
>
>
>
> Hello,
>
> I'm having a problem that I don't remember having some time ago (maybe
> pre 5.10?). Using pvsfread to constantly loop a 1.5 seconds stereo pvx
> file produces different sound each time it loops. I made this short
> csd for testing purposes:
>
> 
> 
>
> sr=48000
> ksmps=64
> nchnls=2
>
> instr 1
> ipvxflen filelen "castanetas2b.pvx"
> kposcps = (1/ipvxflen)
> kphasor phasor kposcps
> kpos = ipvxflen * kphasor
>
>
> fsigInlB pvsfread kpos, "castanetas2b.pvx", 0
> fsigInrB pvsfread kpos, "castanetas2b.pvx", 1
>
> aoutL pvsynth fsigInlB
> aoutR pvsynth fsigInrB
>
> outc aoutL, aoutR
> endin
>
> 
> 
> i1 0 20
> e
> 
> 
>
> The file "castanetas2b.pvx" can be found here in case it has something
> to do with the problem (it was created using pvanal -n1024):
> http://www.hcenteno.net/audio/castanetas2b.pvx
>
> And this is how it sounds rendered in my system using Fedora 10 and
> Csound 5.10: http://www.hcenteno.net/audio/castanetast_test.wav
>
> Another odd thing is that there is a pause between each repetition
> while there is no such thing when looping the original wav.
>
> Thanks!
>
> Hector
>
>
> Send bugs reports to this list.
> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe csound"
>
>
>
>
> Send bugs reports to this list.
> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe csound"
>

Hello again,

Just for testing I built Csound form CVS and it gives the same
problematic results.

Regards,

Hector


On Sun, May 24, 2009 at 3:19 PM, victor  wrote:
> Which version are you using, CVS?
> ----- Original Message ----- From: "Hector Centeno" 
> To: 
> Sent: Sunday, May 24, 2009 7:32 PM
> Subject: [Csnd] looping pvsfread sounds different each time
>
>
>> Hello,
>>
>> I'm having a problem that I don't remember having some time ago (maybe
>> pre 5.10?). Using pvsfread to constantly loop a 1.5 seconds stereo pvx
>> file produces different sound each time it loops. I made this short
>> csd for testing purposes:
>>
>> 
>> 
>>
>> sr=48000
>> ksmps=64
>> nchnls=2
>>
>> instr 1
>> ipvxflen filelen "castanetas2b.pvx"
>> kposcps = (1/ipvxflen)
>> kphasor phasor kposcps
>> kpos = ipvxflen * kphasor
>>
>>
>> fsigInlB pvsfread kpos, "castanetas2b.pvx", 0
>> fsigInrB pvsfread kpos, "castanetas2b.pvx", 1
>>
>> aoutL pvsynth fsigInlB
>> aoutR pvsynth fsigInrB
>>
>> outc aoutL, aoutR
>> endin
>>
>> 
>> 
>> i1 0 20
>> e
>> 
>> 
>>
>> The file "castanetas2b.pvx" can be found here in case it has something
>> to do with the problem (it was created using pvanal -n1024):
>> http://www.hcenteno.net/audio/castanetas2b.pvx
>>
>> And this is how it sounds rendered in my system using Fedora 10 and
>> Csound 5.10: http://www.hcenteno.net/audio/castanetast_test.wav
>>
>> Another odd thing is that there is a pause between each repetition
>> while there is no such thing when looping the original wav.
>>
>> Thanks!
>>
>> Hector
>>
>>
>> Send bugs reports to this list.
>> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe
>> csound"
>
>
>
> Send bugs reports to this list.
> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe
> csound"
>

I wonder if this has to do with interpolation of frames. Did you
say the problem did not happen in earlier versions?
I am quite sure pvsfread has not changed, but I'll take a look.

Victor

----- Original Message ----- 
From: "Hector Centeno" 
To: 
Sent: Monday, May 25, 2009 4:21 AM
Subject: [Csnd] Re: Re: looping pvsfread sounds different each time


> Hello again,
>
> Just for testing I built Csound form CVS and it gives the same
> problematic results.
>
> Regards,
>
> Hector
>
>
> On Sun, May 24, 2009 at 3:19 PM, victor  wrote:
>> Which version are you using, CVS?
>> ----- Original Message ----- From: "Hector Centeno" 
>> To: 
>> Sent: Sunday, May 24, 2009 7:32 PM
>> Subject: [Csnd] looping pvsfread sounds different each time
>>
>>
>>> Hello,
>>>
>>> I'm having a problem that I don't remember having some time ago (maybe
>>> pre 5.10?). Using pvsfread to constantly loop a 1.5 seconds stereo pvx
>>> file produces different sound each time it loops. I made this short
>>> csd for testing purposes:
>>>
>>> 
>>> 
>>>
>>> sr=48000
>>> ksmps=64
>>> nchnls=2
>>>
>>> instr 1
>>> ipvxflen filelen "castanetas2b.pvx"
>>> kposcps = (1/ipvxflen)
>>> kphasor phasor kposcps
>>> kpos = ipvxflen * kphasor
>>>
>>>
>>> fsigInlB pvsfread kpos, "castanetas2b.pvx", 0
>>> fsigInrB pvsfread kpos, "castanetas2b.pvx", 1
>>>
>>> aoutL pvsynth fsigInlB
>>> aoutR pvsynth fsigInrB
>>>
>>> outc aoutL, aoutR
>>> endin
>>>
>>> 
>>> 
>>> i1 0 20
>>> e
>>> 
>>> 
>>>
>>> The file "castanetas2b.pvx" can be found here in case it has something
>>> to do with the problem (it was created using pvanal -n1024):
>>> http://www.hcenteno.net/audio/castanetas2b.pvx
>>>
>>> And this is how it sounds rendered in my system using Fedora 10 and
>>> Csound 5.10: http://www.hcenteno.net/audio/castanetast_test.wav
>>>
>>> Another odd thing is that there is a pause between each repetition
>>> while there is no such thing when looping the original wav.
>>>
>>> Thanks!
>>>
>>> Hector
>>>
>>>
>>> Send bugs reports to this list.
>>> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe
>>> csound"
>>
>>
>>
>> Send bugs reports to this list.
>> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe
>> csound"
>>
>
>
> Send bugs reports to this list.
> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe 
> csound" 

Thanks Victor,

I don't remember having the same problem before. I noticed this issue
first time recently when I was working with longer PVX files and was
able to hear some sound degradation when looping them for long time.
Then I loaded a shorter one and it became quite obvious. As you can
hear in my example the longer you keep looping the worst it gets, the
transients start to blur and some kind of aliasing appears.

Hector


On Mon, May 25, 2009 at 2:34 AM, victor  wrote:
> I wonder if this has to do with interpolation of frames. Did you
> say the problem did not happen in earlier versions?
> I am quite sure pvsfread has not changed, but I'll take a look.
>
> Victor
>
> ----- Original Message ----- From: "Hector Centeno" 
> To: 
> Sent: Monday, May 25, 2009 4:21 AM
> Subject: [Csnd] Re: Re: looping pvsfread sounds different each time
>
>
>> Hello again,
>>
>> Just for testing I built Csound form CVS and it gives the same
>> problematic results.
>>
>> Regards,
>>
>> Hector
>>
>>
>> On Sun, May 24, 2009 at 3:19 PM, victor  wrote:
>>>
>>> Which version are you using, CVS?
>>> ----- Original Message ----- From: "Hector Centeno" 
>>> To: 
>>> Sent: Sunday, May 24, 2009 7:32 PM
>>> Subject: [Csnd] looping pvsfread sounds different each time
>>>
>>>
>>>> Hello,
>>>>
>>>> I'm having a problem that I don't remember having some time ago (maybe
>>>> pre 5.10?). Using pvsfread to constantly loop a 1.5 seconds stereo pvx
>>>> file produces different sound each time it loops. I made this short
>>>> csd for testing purposes:
>>>>
>>>> 
>>>> 
>>>>
>>>> sr=48000
>>>> ksmps=64
>>>> nchnls=2
>>>>
>>>> instr 1
>>>> ipvxflen filelen "castanetas2b.pvx"
>>>> kposcps = (1/ipvxflen)
>>>> kphasor phasor kposcps
>>>> kpos = ipvxflen * kphasor
>>>>
>>>>
>>>> fsigInlB pvsfread kpos, "castanetas2b.pvx", 0
>>>> fsigInrB pvsfread kpos, "castanetas2b.pvx", 1
>>>>
>>>> aoutL pvsynth fsigInlB
>>>> aoutR pvsynth fsigInrB
>>>>
>>>> outc aoutL, aoutR
>>>> endin
>>>>
>>>> 
>>>> 
>>>> i1 0 20
>>>> e
>>>> 
>>>> 
>>>>
>>>> The file "castanetas2b.pvx" can be found here in case it has something
>>>> to do with the problem (it was created using pvanal -n1024):
>>>> http://www.hcenteno.net/audio/castanetas2b.pvx
>>>>
>>>> And this is how it sounds rendered in my system using Fedora 10 and
>>>> Csound 5.10: http://www.hcenteno.net/audio/castanetast_test.wav
>>>>
>>>> Another odd thing is that there is a pause between each repetition
>>>> while there is no such thing when looping the original wav.
>>>>
>>>> Thanks!
>>>>
>>>> Hector
>>>>
>>>>
>>>> Send bugs reports to this list.
>>>> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe
>>>> csound"
>>>
>>>
>>>
>>> Send bugs reports to this list.
>>> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe
>>> csound"
>>>
>>
>>
>> Send bugs reports to this list.
>> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe
>> csound"
>
>
>
> Send bugs reports to this list.
> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe
> csound"
>

Hello again,

So I installed Csound 5.03 and tested the same orchestra. It seems
that I was wrong about previous versions not presenting this problem
but it actually behaves different. These are the renders in both
versions:

Csound 5.10: http://www.hcenteno.net/audio/castanetas_test.wav
Csound 5.03: http://www.hcenteno.net/audio/castanetas_test2.wav

Even if pvsfread was considered not suitable for looping, the first
time it plays (under both versions) the sound is far from the
original. On the other hand, when looping it is not until the 3rd or
4th iteration that it sounds like the original.

I hope this info is helpful.

Cheers,

Hector


On Mon, May 25, 2009 at 2:34 AM, victor  wrote:
> I wonder if this has to do with interpolation of frames. Did you
> say the problem did not happen in earlier versions?
> I am quite sure pvsfread has not changed, but I'll take a look.
>
> Victor
>
> ----- Original Message ----- From: "Hector Centeno" 
> To: 
> Sent: Monday, May 25, 2009 4:21 AM
> Subject: [Csnd] Re: Re: looping pvsfread sounds different each time
>
>
>> Hello again,
>>
>> Just for testing I built Csound form CVS and it gives the same
>> problematic results.
>>
>> Regards,
>>
>> Hector
>>
>>
>> On Sun, May 24, 2009 at 3:19 PM, victor  wrote:
>>>
>>> Which version are you using, CVS?
>>> ----- Original Message ----- From: "Hector Centeno" 
>>> To: 
>>> Sent: Sunday, May 24, 2009 7:32 PM
>>> Subject: [Csnd] looping pvsfread sounds different each time
>>>
>>>
>>>> Hello,
>>>>
>>>> I'm having a problem that I don't remember having some time ago (maybe
>>>> pre 5.10?). Using pvsfread to constantly loop a 1.5 seconds stereo pvx
>>>> file produces different sound each time it loops. I made this short
>>>> csd for testing purposes:
>>>>
>>>> 
>>>> 
>>>>
>>>> sr=48000
>>>> ksmps=64
>>>> nchnls=2
>>>>
>>>> instr 1
>>>> ipvxflen filelen "castanetas2b.pvx"
>>>> kposcps = (1/ipvxflen)
>>>> kphasor phasor kposcps
>>>> kpos = ipvxflen * kphasor
>>>>
>>>>
>>>> fsigInlB pvsfread kpos, "castanetas2b.pvx", 0
>>>> fsigInrB pvsfread kpos, "castanetas2b.pvx", 1
>>>>
>>>> aoutL pvsynth fsigInlB
>>>> aoutR pvsynth fsigInrB
>>>>
>>>> outc aoutL, aoutR
>>>> endin
>>>>
>>>> 
>>>> 
>>>> i1 0 20
>>>> e
>>>> 
>>>> 
>>>>
>>>> The file "castanetas2b.pvx" can be found here in case it has something
>>>> to do with the problem (it was created using pvanal -n1024):
>>>> http://www.hcenteno.net/audio/castanetas2b.pvx
>>>>
>>>> And this is how it sounds rendered in my system using Fedora 10 and
>>>> Csound 5.10: http://www.hcenteno.net/audio/castanetast_test.wav
>>>>
>>>> Another odd thing is that there is a pause between each repetition
>>>> while there is no such thing when looping the original wav.
>>>>
>>>> Thanks!
>>>>
>>>> Hector
>>>>
>>>>
>>>> Send bugs reports to this list.
>>>> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe
>>>> csound"
>>>
>>>
>>>
>>> Send bugs reports to this list.
>>> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe
>>> csound"
>>>
>>
>>
>> Send bugs reports to this list.
>> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe
>> csound"
>
>
>
> Send bugs reports to this list.
> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe
> csound"
>

Could you be so kind to compare it with pvread?
----- Original Message ----- 
From: "Hector Centeno" 
To: 
Sent: Thursday, May 28, 2009 1:18 AM
Subject: [Csnd] Re: Re: Re: Re: looping pvsfread sounds different each time


> Hello again,
>
> So I installed Csound 5.03 and tested the same orchestra. It seems
> that I was wrong about previous versions not presenting this problem
> but it actually behaves different. These are the renders in both
> versions:
>
> Csound 5.10: http://www.hcenteno.net/audio/castanetas_test.wav
> Csound 5.03: http://www.hcenteno.net/audio/castanetas_test2.wav
>
> Even if pvsfread was considered not suitable for looping, the first
> time it plays (under both versions) the sound is far from the
> original. On the other hand, when looping it is not until the 3rd or
> 4th iteration that it sounds like the original.
>
> I hope this info is helpful.
>
> Cheers,
>
> Hector
>
>
> On Mon, May 25, 2009 at 2:34 AM, victor  wrote:
>> I wonder if this has to do with interpolation of frames. Did you
>> say the problem did not happen in earlier versions?
>> I am quite sure pvsfread has not changed, but I'll take a look.
>>
>> Victor
>>
>> ----- Original Message ----- From: "Hector Centeno" 
>> To: 
>> Sent: Monday, May 25, 2009 4:21 AM
>> Subject: [Csnd] Re: Re: looping pvsfread sounds different each time
>>
>>
>>> Hello again,
>>>
>>> Just for testing I built Csound form CVS and it gives the same
>>> problematic results.
>>>
>>> Regards,
>>>
>>> Hector
>>>
>>>
>>> On Sun, May 24, 2009 at 3:19 PM, victor  
>>> wrote:
>>>>
>>>> Which version are you using, CVS?
>>>> ----- Original Message ----- From: "Hector Centeno" 
>>>> To: 
>>>> Sent: Sunday, May 24, 2009 7:32 PM
>>>> Subject: [Csnd] looping pvsfread sounds different each time
>>>>
>>>>
>>>>> Hello,
>>>>>
>>>>> I'm having a problem that I don't remember having some time ago (maybe
>>>>> pre 5.10?). Using pvsfread to constantly loop a 1.5 seconds stereo pvx
>>>>> file produces different sound each time it loops. I made this short
>>>>> csd for testing purposes:
>>>>>
>>>>> 
>>>>> 
>>>>>
>>>>> sr=48000
>>>>> ksmps=64
>>>>> nchnls=2
>>>>>
>>>>> instr 1
>>>>> ipvxflen filelen "castanetas2b.pvx"
>>>>> kposcps = (1/ipvxflen)
>>>>> kphasor phasor kposcps
>>>>> kpos = ipvxflen * kphasor
>>>>>
>>>>>
>>>>> fsigInlB pvsfread kpos, "castanetas2b.pvx", 0
>>>>> fsigInrB pvsfread kpos, "castanetas2b.pvx", 1
>>>>>
>>>>> aoutL pvsynth fsigInlB
>>>>> aoutR pvsynth fsigInrB
>>>>>
>>>>> outc aoutL, aoutR
>>>>> endin
>>>>>
>>>>> 
>>>>> 
>>>>> i1 0 20
>>>>> e
>>>>> 
>>>>> 
>>>>>
>>>>> The file "castanetas2b.pvx" can be found here in case it has something
>>>>> to do with the problem (it was created using pvanal -n1024):
>>>>> http://www.hcenteno.net/audio/castanetas2b.pvx
>>>>>
>>>>> And this is how it sounds rendered in my system using Fedora 10 and
>>>>> Csound 5.10: http://www.hcenteno.net/audio/castanetast_test.wav
>>>>>
>>>>> Another odd thing is that there is a pause between each repetition
>>>>> while there is no such thing when looping the original wav.
>>>>>
>>>>> Thanks!
>>>>>
>>>>> Hector
>>>>>
>>>>>
>>>>> Send bugs reports to this list.
>>>>> To unsubscribe, send email sympa@lists.bath.ac.uk with body 
>>>>> "unsubscribe
>>>>> csound"
>>>>
>>>>
>>>>
>>>> Send bugs reports to this list.
>>>> To unsubscribe, send email sympa@lists.bath.ac.uk with body 
>>>> "unsubscribe
>>>> csound"
>>>>
>>>
>>>
>>> Send bugs reports to this list.
>>> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe
>>> csound"
>>
>>
>>
>> Send bugs reports to this list.
>> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe
>> csound"
>>
>
>
> Send bugs reports to this list.
> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe 
> csound" 

There is an inherent problem with looping phase vocoder files, as I 
found out a while back in implementing a standalone player. The problem 
is, as usual, the phase, or rather the running accumulation of it. When 
a performance starts phases are reset to a default position (e.g. all 
zero, as the CARL code does); and the phases naturally cycle along as 
the sound is rendered. One may say that at the end of the sound, the 
final phase values represent in a sense the whole history of the sound. 
To get a seamless (glitch-free) looping, one has no choice but to resume 
with whatever the current phase values are, and very often (I would say 
probably always), the sound will be different, sometimes extremely so.

It is a bit like a group of athletes running a race. They all start off 
in a tidy line, but usually end randomly distributed. Then you ask them 
to run the race again, but with the same relative positions they had at 
the end. The result will be different each time (the faster runners may 
tire more than the plodders, etc), so that perchance from time to time 
they will start in a line again.

I have not found a solution to this. Inevitably, zeroing or otherwise 
resetting the phases at the loop point will introduce a glitch. The only 
thing I have so far thought of is simply crossfading the start of a new 
render with the end of the previous one - hardly ideal.


Richard Dobson


victor wrote:
> Could you be so kind to compare it with pvread?
> ----- Original Message ----- From: "Hector Centeno" 
> To: 
> Sent: Thursday, May 28, 2009 1:18 AM
> Subject: [Csnd] Re: Re: Re: Re: looping pvsfread sounds different each time
> 
> 
>> Hello again,
>>
>> So I installed Csound 5.03 and tested the same orchestra. It seems
>> that I was wrong about previous versions not presenting this problem
>> but it actually behaves different. These are the renders in both
>> versions:
>>