Add support for AMR-WB+ codec

[boris]

FFmpeg currently does not have a decoder for AMR-WB+ codec.

A free encoder + decoder for AMR-WB+ can be downloaded from ​https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=1451. The ZIP file has both binaries (encoder.exe, decoder.exe) and source code.

Here are some usage instructions,

$ wget http://www.music.helsinki.fi/tmt/opetus/uusmedia/esim/a2002011001-e02-16kHz.wav

$ wine encoder.exe -rate 16 -if a2002011001-e02-16kHz.wav -of out.3gp
3gp File Format
Encoding @  16.00kbps
 --- Running ---

$ mediainfo out.3gp
General
Complete name                            : out.3gp
Format                                   : MPEG-4
Format profile                           : 3GPP Media Release 6 Basic
Codec ID                                 : 3gp6 (3gp6/isom)
File size                                : 110 KiB
Duration                                 : 54 s 160 ms
Overall bit rate mode                    : Constant
Overall bit rate                         : 16.7 kb/s
Encoded date                             : UTC 2017-02-10 06:10:58
Tagged date                              : UTC 2017-02-10 06:10:58

Audio
ID                                       : 1
Format                                   : sawp
Codec ID                                 : sawp
Duration                                 : 54 s 160 ms
Bit rate mode                            : Constant
Bit rate                                 : 16.2 kb/s
Channel(s)                               : 2 channels
Sampling rate                            : 6 464 Hz
Bit depth                                : 16 bits
Stream size                              : 107 KiB (97%)
Encoded date                             : UTC 2017-02-10 06:10:58
Tagged date                              : UTC 2017-02-10 06:10:58

$ wine decoder.exe  -if out.3gp  -of out.wav
...
File type brand '3gp6' minor version 256
Compatible brands: 'isom' (yes) '3gp4' (no) '3gp5' (no)
Track 1 'sawp'  Duration 54.160s  Time scale 72000
Decoding @  16.00kbps

$ mediainfo out.wav
General
Complete name                            : out.wav
Format                                   : Wave
File size                                : 9.92 MiB
Duration                                 : 54 s 160 ms
Overall bit rate mode                    : Constant
Overall bit rate                         : 1 536 kb/s

Audio
Format                                   : PCM
Format settings, Endianness              : Little
Format settings, Sign                    : Signed
Codec ID                                 : 1
Duration                                 : 54 s 160 ms
Bit rate mode                            : Constant
Bit rate                                 : 1 536 kb/s
Channel(s)                               : 2 channels
Sampling rate                            : 48.0 kHz
Bit depth                                : 16 bits
Stream size                              : 9.92 MiB (100%)

It would be great to get support for AMR-WB+ codec in FFmpeg.

[boris]

Audio sample using AMR-WB+ codec

[boris]

​http://samples.mplayerhq.hu/A-codecs/amr/amr-wb+_encoded/ has another sample which is correctly decoded by "decoder.exe".

https://ffmpeg.org/pipermail/ffmpeg-devel/2008-December/044239.html also seems relevant to this ticket.