Hi EZ and Robert, The knee width in the DSP System Toolbox Dynamic Range Compressor is based on the following reference (available online): 'Digital Dynamic Range Compressor Design - Tutorial and Analysis', Giannoulis, Dimitrios; Massberg, Michael; Reiss, Joshua D., JAES Volume 60 Issue 6 pp. 399-408; June 2012
More specifically, the soft knee characteristic of Equation (4) is implemented. The knee width may be specified in dB on the compressor. There is a figure in the example I linked to that shows the static compression characteristic for knee widths of 0, 5 and 10 dB. Thanks, Jihad -----Original Message----- From: music-dsp-boun...@music.columbia.edu [mailto:music-dsp-boun...@music.columbia.edu] On Behalf Of zhiguang e zhang Sent: Tuesday, July 15, 2014 7:14 PM To: A discussion list for music-related DSP Subject: Re: [music-dsp] scripted dynamics compression Another one here interested in how the knee was implemented. EZ On Jul 15, 2014, at 5:13 PM, robert bristow-johnson <r...@audioimagination.com> wrote: > On 7/15/14 10:06 AM, Jihad Ibrahim wrote: >> MATLAB ships a dynamic range compressor and a dynamic range expender as part >> of the DSP System Toolbox. The dynamic range compressor allows you to >> control multiple compression parameters, such as the compression ratio, >> threshold, knee width, make up gain, and attack and release times. You can >> use it in a MATLAB script. >> >> For information on this functionality, you can refer to the 'Dynamic Range >> Compression' section of the following example: >> http://www.mathworks.com/help/dsp/examples/multiband-dynamic-range-co >> mpression.html#zmw57dd0e6282 >> > > i'd like to see mathematically how the MATLAB compressor defines the knee > (and the knee width). can anyone (perhaps with access to the source code) > say? > > -- > > r b-j r...@audioimagination.com > > "Imagination is more important than knowledge." > > > > -- > dupswapdrop -- the music-dsp mailing list and website: > subscription info, FAQ, source code archive, list archive, book > reviews, dsp links http://music.columbia.edu/cmc/music-dsp > http://music.columbia.edu/mailman/listinfo/music-dsp -- dupswapdrop -- the music-dsp mailing list and website: subscription info, FAQ, source code archive, list archive, book reviews, dsp links http://music.columbia.edu/cmc/music-dsp http://music.columbia.edu/mailman/listinfo/music-dsp -- dupswapdrop -- the music-dsp mailing list and website: subscription info, FAQ, source code archive, list archive, book reviews, dsp links http://music.columbia.edu/cmc/music-dsp http://music.columbia.edu/mailman/listinfo/music-dsp
