avcodec: Remove libaacplus

TODO: bump minor

It's inferior in quality to fdk-aac and has an arguably more problematic
license.

As early as 2012, a HydrogenAudio user reported:

> It has however one huge advantage: much better quality at low bitrates than
> faac and libaacplus.

(https://hydrogenaud.io/index.php?PHPSESSID=ckiq394pdglka0kj2fin6ij8t7&topic=95989.msg804633#msg804633)

I myself have made a few spectrograms for a comparison of the two
encoders as well. The FDK output is consistently better than the
libaacplus one, in all bitrates I tested.

libaacplus license is 3GPP + LGPLv2. 3GPP copyright notice is completely
proprietory, as follows:

> No part may be reproduced except as authorized by written permission.
>
> The copyright and the foregoing restriction extend to reproduction in
> all media.
>
> © 2008, 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TTA, TTC).
>
> All rights reserved.

(The latest 26410-d00 zip from 3GPP has the same notice, but the copyright
year is changed to 2015)

The copyright part of the FDK AAC license (section 2) is a copyleft
license that permits redistribution under certain conditions (and
therefore the LGPL + libfdk-aac combination is not prohibited by
configure):

> Redistribution and use in source and binary forms, with or without
> modification, are permitted without payment of copyright license fees
> provided that you satisfy the following conditions:
>
> You must retain the complete text of this software license in
> redistributions of the FDK AAC Codec or your modifications thereto in
> source code form.
>
> You must retain the complete text of this software license in the
> documentation and/or other materials provided with redistributions of
> the FDK AAC Codec or your modifications thereto in binary form.
>
> You must make available free of charge copies of the complete source
> code of the FDK AAC Codec and your modifications thereto to recipients
> of copies in binary form.
>
> The name of Fraunhofer may not be used to endorse or promote products
> derived from this library without prior written permission.
>
> You may not charge copyright license fees for anyone to use, copy or
> distribute the FDK AAC Codec software or your modifications thereto.
>
> Your modified versions of the FDK AAC Codec must carry prominent
> notices stating that you changed the software and the date of any
> change. For modified versions of the FDK AAC Codec, the term
> "Fraunhofer FDK AAC Codec Library for Android" must be replaced by the
> term "Third-Party Modified Version of the Fraunhofer FDK AAC Codec
> Library for Android."

Changelog

@@ -60,6 +60,7 @@ version <next>:
 - convolution filter
 - libquvi support removed
 - support for dvaudio in wav and avi
+- libaacplus support removed
 
 
 version 2.8:

LICENSE.md

@@ -104,7 +104,7 @@ license version needs to be upgraded by passing `--enable-version3` to configure
 incompatible libraries
 ----------------------
 
-The Fraunhofer AAC library, FAAC and aacplus are under licenses which
+The Fraunhofer AAC library and FAAC are under licenses which
 are incompatible with the GPLv2 and v3. We do not know for certain if their
 licenses are compatible with the LGPL.
 If you wish to enable these libraries, pass `--enable-nonfree` to configure.

configure

@@ -207,7 +207,6 @@ External library support:
                            if openssl is not used [no]
   --disable-iconv          disable iconv [autodetect]
   --enable-ladspa          enable LADSPA audio filtering [no]
-  --enable-libaacplus      enable AAC+ encoding via libaacplus [no]
   --enable-libass          enable libass subtitles rendering,
                            needed for subtitles and ass filter [no]
   --enable-libbluray       enable BluRay reading using libbluray [no]
@@ -1435,7 +1434,6 @@ EXTERNAL_LIBRARY_LIST="
     gnutls
     iconv
     ladspa
-    libaacplus
     libass
     libbluray
     libbs2b
@@ -2604,7 +2602,6 @@ mjpeg2jpeg_bsf_select="jpegtables"
 
 # external libraries
 chromaprint_muxer_deps="chromaprint"
-libaacplus_encoder_deps="libaacplus"
 libcelt_decoder_deps="libcelt"
 libdcadec_decoder_deps="libdcadec"
 libfaac_encoder_deps="libfaac"
@@ -4888,7 +4885,6 @@ die_license_disabled gpl libxavs
 die_license_disabled gpl libxvid
 die_license_disabled gpl x11grab
 
-die_license_disabled nonfree libaacplus
 die_license_disabled nonfree libfaac
 die_license_disabled nonfree nvenc
 enabled gpl && die_license_disabled_gpl nonfree libfdk_aac
@@ -5464,7 +5460,6 @@ enabled gmp               && require2 gmp gmp.h mpz_export -lgmp
 enabled gnutls            && require_pkg_config gnutls gnutls/gnutls.h gnutls_global_init
 enabled ladspa            && { check_header ladspa.h || die "ERROR: ladspa.h header not found"; }
 enabled libiec61883       && require libiec61883 libiec61883/iec61883.h iec61883_cmp_connect -lraw1394 -lavc1394 -lrom1394 -liec61883
-enabled libaacplus        && require "libaacplus >= 2.0.0" aacplus.h aacplusEncOpen -laacplus
 enabled libass            && require_pkg_config libass ass/ass.h ass_library_init
 enabled libbluray         && require_pkg_config libbluray libbluray/bluray.h bd_open
 enabled libbs2b           && require_pkg_config libbs2b bs2b.h bs2b_open

doc/general.texi

@@ -881,10 +881,10 @@ following image formats are supported:
 @item Name @tab Encoding @tab Decoding @tab Comments
 @item 8SVX exponential       @tab     @tab  X
 @item 8SVX fibonacci         @tab     @tab  X
-@item AAC+                   @tab  E  @tab  IX
-    @tab encoding supported through external library libaacplus
 @item AAC                    @tab  E  @tab  X
-    @tab encoding supported through external library libfaac and libvo-aacenc
+    @tab encoding supported through external library libfaac, libfdk-aac and libvo-aacenc
+@item AAC+                   @tab  E  @tab  IX
+    @tab encoding supported through external library libfdk-aac
 @item AC-3                   @tab IX  @tab  IX
 @item ADPCM 4X Movie         @tab     @tab  X
 @item APDCM Yamaha AICA      @tab     @tab  X

doc/platform.texi

@@ -314,7 +314,7 @@ These library packages are only available from
 @uref{http://sourceware.org/cygwinports/, Cygwin Ports}:
 
 @example
-yasm, libSDL-devel, libfaac-devel, libaacplus-devel, libgsm-devel, libmp3lame-devel,
+yasm, libSDL-devel, libfaac-devel, libgsm-devel, libmp3lame-devel,
 libschroedinger1.0-devel, speex-devel, libtheora-devel, libxvidcore-devel
 @end example
 

libavcodec/Makefile

@@ -798,7 +798,6 @@ OBJS-$(CONFIG_WTV_DEMUXER)             += mpeg4audio.o mpegaudiodata.o
 OBJS-$(CONFIG_ELBG_FILTER)             += elbg.o
 
 # external codec libraries
-OBJS-$(CONFIG_LIBAACPLUS_ENCODER)         += libaacplus.o
 OBJS-$(CONFIG_LIBCELT_DECODER)            += libcelt_dec.o
 OBJS-$(CONFIG_LIBDCADEC_DECODER)          += libdcadec.o dca.o
 OBJS-$(CONFIG_LIBFAAC_ENCODER)            += libfaac.o

libavcodec/allcodecs.c

@@ -593,7 +593,6 @@ void avcodec_register_all(void)
     REGISTER_ENCODER(LIBXAVS,           libxavs);
     REGISTER_ENCODER(LIBXVID,           libxvid);
     REGISTER_DECODER(LIBZVBI_TELETEXT,  libzvbi_teletext);
-    REGISTER_ENCODER(LIBAACPLUS,        libaacplus);
 
     /* text */
     REGISTER_DECODER(BINTEXT,           bintext);