On Fri, 18 Feb 2011 21:20:15 +0000 Fons Adriaensen <f...@linuxaudio.org> wrote:
> On Fri, Feb 18, 2011 at 11:30:24AM -0800, Mark Knecht wrote: > > On Wed, Feb 16, 2011 at 10:45 AM, Fons Adriaensen <f...@linuxaudio.org> > > wrote: > > <SNIP> > > > > > > Some filtering followed by RMS detection will provide a good > > > approximation to subjective loudness. > > > > > <SNIP> > > > > Is this part to implement something like like Fletcher-Munson curves? > > In general that is not the case, probably because for most types of > content the mid-frequency range is dominant. And loudness measuring > systems are expected to give good results for typical content, not > to estimate the subjective loudness of single tones or narrow band > signals. > > The filter recommended by the ITU and EBU is a combination of a 2nd > order highpass (around 50 Hz) and a shelf filter providing 4 dB gain > at 4 kHz and above. Listening tests have shown this to work quite > well in practice. > > Ciao, Interesting. Where do they roll off the top end? Or don't they say? -- Will J Godfrey http://www.musically.me.uk Say you have a poem and I have a tune. Exchange them and we can both have a poem, a tune, and a song. _______________________________________________ Linux-audio-dev mailing list Linux-audio-dev@lists.linuxaudio.org http://lists.linuxaudio.org/listinfo/linux-audio-dev
