Signed-off-by: Paul B Mahol <onemda@gmail.com>

The 'sqrt' and 'cbrt' scalers were added in commit
80262d8c86e94ff9a4bb3a9e3c2d734e04ccb399, but their symbolic option values
only made available to the showwaves filter, not showwavespic, despite
the scalers working properly by their numerical option values.

Signed-off-by: Moritz Barsnick <barsnick@gmx.net>

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

Signed-off-by: Paul B Mahol <onemda@gmail.com>

Signed-off-by: Paul B Mahol <onemda@gmail.com>

Many of the functions from avfilter/formats can return errors, usually AVERROR(ENOMEM).
This propagates the return values.

All of these were found by using av_warn_unused_result, demonstrating its utility.

Tested with FATE. I am least sure of the changes to avfilter/filtergraph,
since I don't know what/how reduce_format is intended to behave and how it should
react to errors.

Fixes: CID 1325680, 1325679, 1325678.

Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Previous version Reviewed-by: Nicolas George <george@nsup.org>
Previous version Reviewed-by: Clément Bœsch <u@pkh.me>
Signed-off-by: Ganesh Ajjanagadde <gajjanagadde@gmail.com>

Fixes potential division by zero
Fixes: CID1292295

Reviewed-by: Ganesh Ajjanagadde <gajjanag@mit.edu>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

This is a variant of showwaves. It is implemented as a different filter
so that the user is not allowed to use meaningless options which belong
to showwaves (such as rate).

Major edits done by Stefano Sabatini, from a patch by ubitux.

See thread:
From: Clément Bœsch <u@pkh.me>
To: ffmpeg-devel@ffmpeg.org
Date: Wed, 24 Dec 2014 15:03:26 +0100
Subject: [FFmpeg-devel] [PATCH] avfilter/showwaves: add single_pic option

This fixes depending on implementation defined behavior

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

It caused segfaults.

Signed-off-by: Marton Balint <cus@passwd.hu>
Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

Signed-off-by: Paul B Mahol <onemda@gmail.com>

Signed-off-by: Paul B Mahol <onemda@gmail.com>

Signed-off-by: Paul B Mahol <onemda@gmail.com>

Signed-off-by: Paul B Mahol <onemda@gmail.com>

outpicref is not always in synch with showwaves->outpicref, which is
changed as a side effect of the call to functions.

Fix regression introduced in 5f634480d1c4ed7711a15d1be07e49177cf351c1,
+10l to me.

Found-by: durandal_1707
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

This is following 568c70e79e.

Based on patch by Anton Khirnov
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

Also remove it in once case when it is not needed.

Signed-off-by: Paul B Mahol <onemda@gmail.com>

Also fix Coverity issue CID 733743: Dereference after null check

Signed-off-by: Paul B Mahol <onemda@gmail.com>

This allows the iteration callbacks to discover the internal class and
options, and show them when required.

This reduces from 3 to 2 messages for the same syntax error in ffprobe,
and from 4 to 3 in filters.

The video frame reference is passed along the filterchain, and is not
possessed anymore by the filter. If out_buf is not set to NULL, it will
be freed by ff_end_frame() causing a crash.

Reduce log clutter, consistent with 1a49a169eb.

Fix signature mismatch warnings.

Avoids a huge memleak when n != 1.

The macro can be used to define consistently the internal class of a
filter, save some typing and factorize.