Re: [ecasound] moving from sox, how do I increase volume by X decibels?

-ea amplifies by percentage; db, is a logarithmic scale, so the latter
can't be plugged into the former without first converting it. Also
problematic is that db is a ratio, so there is no specific value for
any given db.

That being said, a good conversion from db to amplitude is:

amp = 10^(db/10)

With this formula, a db of 0.0 would correspond to unity, or 1.0,
negative db values would decrease the amplitude, positive values would
increase it.

This would in turn need to be multiplied by 100 to be a percentage.

Hope that helps,
JP

On Apr 29, 2009, at 11:26 AM, Jason Galyon wrote:

> I am moving a system's dependency on Sox to Ecasound and am not sure
> exactly how to go about increasing volume a set amount of decibels.
> To
> explain, we have xml templates where effects are applied to the audio
> and the current sox based system requires a value in decibels.
>
> I have tried taking the decibel number, multiplying it by 100 and
> giving
> that as a value to '-eva'.
>
> However, my new system produces clipped and loud audio whereas the
> current legacy system is smooth and much quieter.
>
> What is a good algorithm I can implement?
>
> --
> Jason Galyon
> Silver Screen Tele-Reality, Inc.
> http://www.sister.tv | http://www.videocarlot.tv
> Phone: 972-855-3500 | Fax: 413-778-2146
>
>
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Received on Thu Apr 30 00:15:02 2009