[FFmpeg-devel] [PATCH] swresample/resample: add force_comp argument

[Muhammad Faiz]

On 11/24/16, Muhammad Faiz <mfcc64 at gmail.com> wrote:
> On 11/23/16, Michael Niedermayer <michael at niedermayer.cc> wrote:
>> On Mon, Nov 21, 2016 at 02:21:07AM +0700, Muhammad Faiz wrote:
>>> On 11/21/16, Michael Niedermayer <michael at niedermayer.cc> wrote:
>>> > On Sun, Nov 20, 2016 at 03:56:28PM +0700, Muhammad Faiz wrote:
>>> >> this allow to use phase_count_compensation on init (rather than
>>> >> rebuild on swr_set_compensation) when options suggest that
>>> >> soft compensation is enabled
>>> >>
>>> >> Signed-off-by: Muhammad Faiz <mfcc64 at gmail.com>
>>> >> ---
>>> >>  libswresample/resample.c            | 4 +++-
>>> >>  libswresample/soxr_resample.c       | 2 +-
>>> >>  libswresample/swresample.c          | 5 ++++-
>>> >>  libswresample/swresample_internal.h | 3 ++-
>>> >>  4 files changed, 10 insertions(+), 4 deletions(-)
>>> >
>>> > please document this in the code with a comment or 2
>>> > its not immedeatly obvious from reading the code
>>>
>>> ok, new patch attached
>>>
>>> thanks
>>
>>>  resample.c            |    7 ++++++-
>>>  soxr_resample.c       |    3 ++-
>>>  swresample.c          |    7 ++++++-
>>>  swresample_internal.h |    3 ++-
>>>  4 files changed, 16 insertions(+), 4 deletions(-)
>>> ecc69d7aba15455780250ea23b661ebf136656c2
>>> 0001-swresample-resample-add-soft_compensation-argument.patch
>>> From 5846ba0a6df69e41783ab4caa88d392abd339ed1 Mon Sep 17 00:00:00 2001
>>> From: Muhammad Faiz <mfcc64 at gmail.com>
>>> Date: Mon, 21 Nov 2016 02:08:40 +0700
>>> Subject: [PATCH] swresample/resample: add soft_compensation argument
>>>
>>> this allow to use larger phase_count on init (rather than
>>> rebuild on swr_set_compensation) when options suggest that
>>> soft compensation is enabled
>>>
>>> this affects only when exact_rational is enabled
>>
>> what if an application reinitializes the context more often than
>> triggering soft compensation ?
>
> In this case (or in worse condition such as no actual soft compensation
> happens
> because timestamps are correct), the drawback is slower init/reinit,
> slightly
> slower resampling and increased memory usage.
>
>>
>> maybe keeping statistics on actual soft_compensation use vs reinit
>> would be a better deciding factor
>> but maybe iam missing something
>
> How I keep the statistics?
>
> The main goal is to avoid rebuilding filter bank at runtime that
> hurts real time application that use soft compensation e.g.
> AV sync that uses non audio clock.
>
> Actually I'm not sure with this.
>
> Thank's
>

Probably explicit option is better.
I drop this.
Probably I will post a patch with more functionality.

Thank's