- From: Jean-Marc Valin <jmvalin@mozilla.com>
- Date: Thu, 02 May 2013 22:42:36 -0400
- To: Chris Rogers <crogers@google.com>
- CC: Frederick Umminger <frederick.umminger@gmail.com>, "public-audio@w3.org" <public-audio@w3.org>
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 The idea here is just to change the way the signals are specified. In CD audio, you have a 16-bit values, so any instantaneous value between - -32768 and 32767 is valid (any value beyond that is clipped). The problem with specifying the maximum instantaneous value is that it leads to lousness war mastering where everyone is trying to mix as loud as possible, while destroying any sort of dynamic range. In that context, anyone trying to produce a good mix with a decent dynamic range would end up with a recording that's *much* lower than loudness war recordings. What would make more sense (and what I'm proposing) is that instead of specifying the maximum instantaneous value, we just specify the maximum *average* amplitude (e.g. RMS or weighted RMS). Anything that's recorded at or below that level passes through without any sort of modification. Only signals that exceed that level are limited -- in the same was as PCM signals exceeding 32767 are clipped. Now, developers can still use other compression effect as they please, but at least we would have a way to have both uniform audio levels *and* make it possible to have a decent dynamic range. Jean-Marc On 05/02/2013 06:55 PM, Chris Rogers wrote: > I'm not a big fan of the idea of a hard-coded compressor/limiter, > but if there were one then I wouldn't want it touching the signal > at all if the signal remains below 0dBFS. Sound > designers/producers take great care to master their music using > their own mastering compressors/limiters, etc. so should have the > option (the default) to pass their signal through cleanly without > any processing at all. In other words a "straight wire". My idea > with the DynamicsCompressorNode is that developers can choose to > use it, especially in cases where they may be mixing multiple sound > sources together, in which case it can help glue the mix together. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.13 (GNU/Linux) Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iQEcBAEBAgAGBQJRgyQcAAoJEJ6/8sItn9q9214IAIz/hVLrtbK7ohQ3ELGAk216 HBgerLiBTECtok92Wn7jJgPwXhjV/2+HS6DIRv0xU/0pX109EJNG8gLFbju4qnyb wBuiGVrw1VjSk9FKqrRW7i9yurvo/k8axGEAeowYd0xUC52ZfI/dxm+u/POprOFK ZO0rS7M+94sSMmHjzaApU3ZfFB1WvMgP662D6s6t+xPZDCuskx5drv1DWVplwKNS EUTkpcQ6dUfgTrbNgrYa799kAggs7H/1nliQMTbcVSCrS3UFGty5fFCbLOdleCOj WCB8DAnNvP0m2W6q4+taQgHsoXlWXyH6/4ucFVx8uZrAY6wGMn1bkEWPxmuY4IY= =PbNb -----END PGP SIGNATURE-----
Received on Friday, 3 May 2013 02:43:04 UTC