[Libav-user] non-causal or two-pass filters

Stefano Sabatini stefasab at gmail.com
Fri Apr 26 23:44:52 CEST 2013

In data Friday 2013-04-26 21:21:04 +0300, Yaron Segalov ha scritto:
> Is it possible to create a non-causal filter, or even a two-pass filter?


> An example filter: an audio filter which normalizes the audio gain based on
> the MAX gain throughout the entire movie.

There are a few filters which allow to collect data about a stream,
see ebur128 and the astats filter currently reviewed. The problem with
a two-steps process is that we didn't yet designed a mechanism to pass
global data (data collected at the end of the stream processing) to
the outside, right now we log it which may or may not be an optimal
way to send information around. Help in this area is welcome.
FFmpeg = Frightening Fundamental Multipurpose Pacific Eager Glue

More information about the Libav-user mailing list