From f157736ec5ef430512d08a38151626939d52367c Mon Sep 17 00:00:00 2001 From: "Timothy B. Terriberry" <tterribe@xiph.org> Date: Thu, 14 Aug 2014 10:21:41 -0700 Subject: [PATCH] Ogg Opus updates from Ian Nartowicz. These are the changes proposed in <http://www.ietf.org/mail-archive/web/codec/current/msg03058.html>, with some minor additions (see follow-up on the list). --- doc/draft-ietf-codec-oggopus.xml | 15 +++++---------- 1 file changed, 5 insertions(+), 10 deletions(-) diff --git a/doc/draft-ietf-codec-oggopus.xml b/doc/draft-ietf-codec-oggopus.xml index db4542dec..7f5c5ab9d 100644 --- a/doc/draft-ietf-codec-oggopus.xml +++ b/doc/draft-ietf-codec-oggopus.xml @@ -688,9 +688,9 @@ sample *= pow(10, output_gain/(20.0*256)) , <vspace blankLines="1"/> Virtually all players and media frameworks should apply it by default. If a player chooses to apply any volume adjustment or gain modification, such - as the R128_TRACK_GAIN, R128_ALBUM_GAIN (see <xref target="comment_header"/>) - or a user-facing volume knob, the adjustment MUST be applied in addition - to this output gain in order to achieve playback at the desired volume. + as the R128_TRACK_GAIN (see <xref target="comment_header"/>), the adjustment + MUST be applied in addition to this output gain in order to achieve playback + at the normalized volume. <vspace blankLines="1"/> An encoder SHOULD set this field to zero, and instead apply any gain prior to encoding, when this is possible and does not conflict with the user's wishes. @@ -1215,15 +1215,10 @@ If present, R128_TRACK_GAIN and R128_ALBUM_GAIN MUST correctly represent If a player chooses to make use of the R128_TRACK_GAIN tag or the R128_ALBUM_GAIN tag, it MUST apply those gains <spanx style="emph">in addition</spanx> to the 'output gain' value. -</t> -<t> -If an encoder wishes to use R128 normalization, and the output gain is not - otherwise constrained or specified, the encoder SHOULD write the R128 gain - into the 'output gain' field and store a tag containing "R128_TRACK_GAIN=0". -That is, it should assume that by default tools will respect the 'output gain' - field, and not the comment tag. If a tool modifies the ID header's 'output gain' field, it MUST also update or remove the R128_TRACK_GAIN and R128_ALBUM_GAIN comment tags if present. +An encoder should assume that by default tools will respect the 'output gain' + field, and not the comment tag. </t> <t> To avoid confusion with multiple normalization schemes, an Opus comment header -- GitLab