Transfer function?

radiocolonel.it · Jun 16, 2005, 08:29 PM

Quote:

By the way, have you read the kx effects programming guide?

... YES, I have the newest one with the plots of log and exp, but u know sometime i need to ask some to solve confusion in my head. I bought a PC on October 2003... and i'm already able to do a lot of things, i record, do the radio, my site and i learned most of things by myself in this short time,
I really appreciate the help U and Max, Russ are giving me!!!

radiocolonel.it · Jun 17, 2005, 12:39 PM

... Hy Guys, I was making tries with the fuction I posted two days ago:

Quote:

amount should be in [-1..1]

x = input in [-1..1]
y = output
k = 2*amount/(1-amount);

f(x) = (1+k)*x/(1+k*abs(x))

i tried to set a static k and to change some to avoid overflow and i came up with this that seems to work:

Quote:

macints a, 0, in, 0x4
tstneg abs, a, a, 0
macs b, 0.25, abs, 0.75

macints tmp_sign, 0, a, b ;
limit tmp_sign, tmp_sign, 0x3, 0x1 ;
log tmp1, a, 0x1F, 0x1 ; This is
log tmp2, b, 0x1F, 0x1 ;
macsn tmp2, tmp2, 1, 1 ; the division approx
macsn tmp3, tmp1, tmp2, 1 ;
exp result, tmp3, 0x1F, tmp_sign ; i found on the guide

macs out, 0, result, 0.25;

Let me know what u think!

radiocolonel.it · Jun 18, 2005, 02:02 AM

.... Ok, since nobody replied to the above post I tried to work on what i wanted to do and i came up with something that for me is working and u can control the amount of "companding" so u can use it on both low and stronger sources.
If i made some rough error in the code let me know, i'll be glad to learn from my mistakes!!!

http://www.radiocolonel.it/kx/ColHQ_Compander.zip

Russ · Jun 21, 2005, 05:30 AM

Quote:

Originally Posted by radiocolonel.it

Let me know what u think!

Sorry, I was busy the last few days and only had time for quick replies.
That code looks good to me. It looks as though you are doing:
f(x) = x / ( 0.25 + (abs(x) * 0.75) )

And your new version looks like:
x = input sample, y = amount
f(x,y) = x * ( 0.25 + (y * 0.75) ) / ( 0.25 + (abs(x) * (y * 0.75)) )

I do not see any problems with the code, and trying it out, it seems to work pretty good.

-Russ

Russ · Jun 21, 2005, 05:53 AM

Quote:

Originally Posted by Tiger M

By the way, have you read the kx effects programming guide?

Speaking of the kx effects programming guide, where did it go (the new version)? I just noticed that the whole thread about the guide is gone.

Russ · Jun 21, 2005, 06:53 AM

Sorry, after further examination I did notice a problem that is causing the output to be phase inverted.
You should be using limitn instead of limit.

i.e.
limitn tmp_sign, tmp_sign, 0x3, 0x1;

-Russ

radiocolonel.it · Jun 21, 2005, 11:13 AM

Quote:

Originally Posted by Russ

Sorry, I was busy the last few days and only had time for quick replies.
That code looks good to me. It looks as though you are doing:
f(x) = x / ( 0.25 + (abs(x) * 0.75) )

And your new version looks like:
x = input sample, y = amount
f(x,y) = x * ( 0.25 + (y * 0.75) ) / ( 0.25 + (abs(x) * (y * 0.75)) )

I do not see any problems with the code, and trying it out, it seems to work pretty good.

-Russ

Thank so much for your interest and help!

Yes that is the formula i used f(x)=(0.25+k)*x/(0.25+k*abs(x)) k=0.75*amount (i just wrote it differently)

I'm so glad i've been able to make this little plugin!
In almost 6 months i made a lot of progresses in dane programming, at the beginning i was just able to make volume controls!

radiocolonel.it · Jun 21, 2005, 11:16 AM

Quote:

Originally Posted by Russ

Sorry, after further examination I did notice a problem that is causing the output to be phase inverted.
You should be using limitn instead of limit.

i.e.
limitn tmp_sign, tmp_sign, 0x3, 0x1;

-Russ

Thanks! I'll correct my code now!

I uploaded the last version of the programming guide on my site so u can download it:

http://www.radiocolonel.it/kx/KX_Programming.html

Russ · Jun 21, 2005, 11:25 AM

Quote:

Originally Posted by radiocolonel.it

Thanks! I'll correct my code now!

I uploaded the last version of the programming guide on my site so u can download it:

http://www.radiocolonel.it/kx/KX_Programming.html

No problem, glad I could be of some help.
As for the guide, I do not currently need it (I probably even have a copy of it here somehwere myself), I was just wondering what happened to it. In any case, I am glad that it is still available from your sight.

Tiger M · Jun 21, 2005, 12:35 PM

The code is good, it works nice, the problem is that you can never get a perfectly smooth curve with using log and exp in any situation (division,roots etc.), so it's better to do things the traditional way.

radiocolonel.it · Jun 21, 2005, 12:38 PM

Quote:

Originally Posted by Tiger M

The code is good, it works nice, the problem is that you can never get a perfectly smooth curve with using log and exp in any situation (division,roots etc.), so it's better to do things the traditional way.

I understand, this is because it is an approximation.
I'm so glad it works! At the end i've been able to make some is working!!!

This happened because of help of u guys!

Russ · Jun 21, 2005, 01:09 PM

Do you realize that the guide on your site is missing the graph's?

radiocolonel.it · Jun 21, 2005, 01:17 PM

Quote:

Originally Posted by Russ

Do you realize that the guide on your site is missing the graph's?

I don't know, it works on me, try now if it is better

Russ · Jun 21, 2005, 01:18 PM

Ok, now I see them

radiocolonel.it · Jun 21, 2005, 02:58 PM

... Ok, now it works again! http://www.hardwareheaven.com/images/s...big%20grin.gif

Jun 18, 2005, 02:02 AM	#93
radiocolonel.it DriverHeaven Lover Join Date: Jan 2005 Location: Italy Posts: 192 Rep Power: 0	.... Ok, since nobody replied to the above post I tried to work on what i wanted to do and i came up with something that for me is working and u can control the amount of "companding" so u can use it on both low and stronger sources. If i made some rough error in the code let me know, i'll be glad to learn from my mistakes!!! http://www.radiocolonel.it/kx/ColHQ_Compander.zip __________________ http://www.rossanodembech.it Last edited by radiocolonel.it; Jun 18, 2005 at 02:58 AM.

Jun 21, 2005, 02:58 PM	#105
radiocolonel.it DriverHeaven Lover Join Date: Jan 2005 Location: Italy Posts: 192 Rep Power: 0	... Ok, now it works again! http://www.hardwareheaven.com/images/s...big%20grin.gif __________________ http://www.rossanodembech.it

Jun 21, 2005, 06:53 AM	#96
Russ HardwareHeaven Extreme Member Join Date: Jan 2005 Posts: 5,563 Rep Power: 62	Sorry, after further examination I did notice a problem that is causing the output to be phase inverted. You should be using limitn instead of limit. i.e. limitn tmp_sign, tmp_sign, 0x3, 0x1; -Russ

Jun 21, 2005, 12:35 PM	#100
Tiger M kX user Join Date: Apr 2004 Posts: 851 Rep Power: 0	The code is good, it works nice, the problem is that you can never get a perfectly smooth curve with using log and exp in any situation (division,roots etc.), so it's better to do things the traditional way.

Jun 21, 2005, 01:09 PM	#102
Russ HardwareHeaven Extreme Member Join Date: Jan 2005 Posts: 5,563 Rep Power: 62	Do you realize that the guide on your site is missing the graph's?

Jun 21, 2005, 01:18 PM	#104
Russ HardwareHeaven Extreme Member Join Date: Jan 2005 Posts: 5,563 Rep Power: 62	Ok, now I see them