[FFmpeg-devel] [PATCH] avfilter: add loudnorm
k at ylo.ph
Wed Apr 6 22:28:13 CEST 2016
On Wed, Apr 6, 2016 at 10:02 AM, Clément Bœsch <u at pkh.me> wrote:
> On Wed, Apr 06, 2016 at 09:52:51AM -0500, Kyle Swanson wrote:
>> On Wed, Apr 6, 2016 at 12:45 AM, Clément Bœsch <u at pkh.me> wrote:
>> > On Tue, Apr 05, 2016 at 07:01:14PM -0500, Kyle Swanson wrote:
>> >> Here's another audio filter. I hinted at this a few months ago, but I found out that
>> >> finishing the last 5% took almost as long as the first 95%. This is an EBU R128
>> >> dynamic loudness normalization filter. This filter uses libebur128 v1.1.0 and must be
>> >> configured with `--enable-libebur128'. Please also see the accompanying blog post
>> >> which has an algorithm description, as well as some usage instructions.
>> >>  https://github.com/jiixyj/libebur128
>> >>  http://k.ylo.ph/2016/04/04/loudnorm.html
>> >> Thanks!
>> >> Kyle
>> >> Signed-off-by: Kyle Swanson <k at ylo.ph>
>> >> ---
>> >> Changelog | 1 +
>> >> MAINTAINERS | 1 +
>> >> configure | 5 +
>> >> doc/filters.texi | 42 +++
>> >> libavfilter/Makefile | 1 +
>> >> libavfilter/af_loudnorm.c | 905 ++++++++++++++++++++++++++++++++++++++++++++++
>> >> libavfilter/allfilters.c | 1 +
>> >> libavfilter/version.h | 4 +-
>> >> 8 files changed, 958 insertions(+), 2 deletions(-)
>> >> create mode 100644 libavfilter/af_loudnorm.c
>> > Mmh. That's nice and all but... why not use/adjust the native ebur128
>> > filter we have instead of relying on an external library?
>> > [...]
>> > --
>> > Clément B.
>> This could be an option for the future. We'll need to break all the
>> EBU R128 logic out into utility functions
> why? what do you need exactly from the filter? The meta are exported in
> each audio frame.
That could work, but in this filter there is a second internal
loudness measurement. Frame meta would only work for the input stream.
>> and update it to use the newest version BS.1770 so it can be used by
>> both filters. Using libebur128 is a
>> good option because it is widely used, actively developed, and updated
>> whenever the spec changes.
> except it's an external dependency and we have code builtin available,
> doing the same thing, and with no open issue (afaik).
> Clément B.
> ffmpeg-devel mailing list
> ffmpeg-devel at ffmpeg.org
More information about the ffmpeg-devel