ralf: fix mono support

[ami_stuff]

​https://www.datafilehost.com/d/9256aef0

C:\>ffmpegx -i lossless_8khz_mono.ra out.wav
ffmpeg version N-79343-g901b0f1 Copyright (c) 2000-2016 the FFmpeg developers
  built with gcc 4.5.0 (GCC) 20100414 (Fedora MinGW 4.5.0-1.fc14)
  configuration: --prefix=/var/www/users/research/ffmpeg/snapshots/build --arch=
x86 --target-os=mingw32 --cross-prefix=i686-pc-mingw32- --cc='ccache i686-pc-min
gw32-gcc' --enable-pthreads --enable-memalign-hack --enable-runtime-cpudetect --
enable-cross-compile --enable-static --disable-shared --extra-libs='-lws2_32 -lw
inmm -lpthread' --extra-cflags='--static -I/var/www/users/research/ffmpeg/snapsh
ots/build/include' --extra-ldflags='-static -L/var/www/users/research/ffmpeg/sna
pshots/build/lib' --enable-bzlib --enable-zlib --enable-gpl --enable-version3 --
enable-nonfree --enable-libx264 --enable-libspeex --enable-libtheora --enable-li
bvorbis --enable-libfaac --enable-libxvid --enable-libopencore-amrnb --enable-li
bopencore-amrwb --enable-libmp3lame --enable-libfreetype --enable-libvpx --disab
le-decoder=libvpx
  libavutil      55. 20.100 / 55. 20.100
  libavcodec     57. 34.100 / 57. 34.100
  libavformat    57. 33.100 / 57. 33.100
  libavdevice    57.  0.101 / 57.  0.101
  libavfilter     6. 41.100 /  6. 41.100
  libswscale      4.  1.100 /  4.  1.100
  libswresample   2.  0.101 /  2.  0.101
  libpostproc    54.  0.100 / 54.  0.100
[rm @ 0x2884020] Invalid stream index 1 for index at pos 275061
[rm @ 0x2884020] Invalid stream index 2 for index at pos 275081
Input #0, rm, from 'lossless_8khz_mono.ra':
  Metadata:
    title           :
    author          :
    copyright       :
    comment         :
    Audiences       : dtdrive_custom_audience;
    audioMode       : music
    Creation Date   : 4/13/2016 18:34:27
    Generated By    : Helix Producer SDK 11.1 for Windows, Build 11.1.0.2848
    Modification Date: 4/13/2016 18:34:27
    videoMode       : normal
    ASMRuleBook     : AverageBandwidth=64000,MaximumBandwidth=128125,TimeStampDe
livery=TRUE,marker=0;AverageBandwidth=0,MaximumBandwidth=0,TimeStampD
    SDPData         : a=fmtp:96 streamtype=5; profile-level-id=254; mode=generic
; objecttype=192; config=4c53443a010300000001001000001f40000020000000
  Duration: 00:00:30.10, start: 0.000000, bitrate: 73 kb/s
    Stream #0:0: Audio: ralf (LSD[58] / 0x3A44534C), 8000 Hz, mono, s16p, 72 kb/
s
[wav @ 0x288c420] Using AVStream.codec to pass codec parameters to muxers is dep
recated, use AVStream.codecpar instead.
Output #0, wav, to 'out.wav':
  Metadata:
    INAM            :
    author          :
    ICOP            :
    ICMT            :
    Audiences       : dtdrive_custom_audience;
    audioMode       : music
    Creation Date   : 4/13/2016 18:34:27
    Generated By    : Helix Producer SDK 11.1 for Windows, Build 11.1.0.2848
    Modification Date: 4/13/2016 18:34:27
    videoMode       : normal
    ASMRuleBook     : AverageBandwidth=64000,MaximumBandwidth=128125,TimeStampDe
livery=TRUE,marker=0;AverageBandwidth=0,MaximumBandwidth=0,TimeStampD
    SDPData         : a=fmtp:96 streamtype=5; profile-level-id=254; mode=generic
; objecttype=192; config=4c53443a010300000001001000001f40000020000000
    ISFT            : Lavf57.33.100
    Stream #0:0: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 8000 Hz, mono, s16, 1
28 kb/s
    Metadata:
      encoder         : Lavc57.34.100 pcm_s16le
Stream mapping:
  Stream #0:0 -> #0:0 (ralf (native) -> pcm_s16le (native))
Press [q] to stop, [?] for help
[ralf @ 0x288c020] I'm pedaling backwards
    Last message repeated 1 times
[ralf @ 0x288c020] Sir, I got carsick in your office. Not decoding the rest of p
acket.
[ralf @ 0x288c020] I'm pedaling backwards
    Last message repeated 50 times
[ralf @ 0x288c020] Sir, I got carsick in your office. Not decoding the rest of p
acket.
[ralf @ 0x288c020] I'm pedaling backwards
    Last message repeated 13 times
[ralf @ 0x288c020] Sir, I got carsick in your office. Not decoding the rest of p
acket.
[ralf @ 0x288c020] I'm pedaling backwards
    Last message repeated 9 times
lossless_8khz_mono.ra: I/O error
size=      54kB time=00:00:29.56 bitrate=  14.8kbits/s speed= 378x
video:0kB audio:54kB subtitle:0kB other streams:0kB global headers:0kB muxing ov
erhead: 0.142377%

[Elon Musk]

Have encoder or decoder?

[ami_stuff]

RealPlayer SP is able to decode (and encode) such files (and probably newer versions too, but I didn't test):

​http://www.oldapps.com/real.php?old_real_player=21?download

​http://www.wine-reviews.net/2009/11/realplayer-sp-102-on-linux-with-wine.html

​http://www.oldapps.com/real.php

[Elon Musk]

Fixed in 9cd2ca9966d0f6c07192a01cbe6184bba0167d05.

[Carl Eugen Hoyos]

While the samples sound fine, everything except 11kHz mono is not bit-exact: There may be an issue with the last frame afaict.

[Elon Musk]

Last frame size or decoded samples are off?

[ami_stuff]

Replying to cehoyos:

While the samples sound fine, everything except 11kHz mono is not bit-exact: There may be an issue with the last frame afaict.

It's hard to compare what is correct and what is not because "RealPlayer Converter" decodes all ra files to 44khz, stereo mode:

​https://www.datafilehost.com/d/9f9ac17f

[Carl Eugen Hoyos]

FFmpeg produces output files that are longer than the wav file you uploaded: Are the Real Converter files also longer?

[ami_stuff]

The output from 44khz stereo ra file seems to match what ffmpeg decoder outputs (if I remember correctly). The rest of the modes I didn't test, but all of the files are in the archive which I posted.