rmdec: fix timestamps for sipr in version 4 container (ra4)

[ami_stuff]

​http://ffmpeg.org/trac/ffmpeg/raw-attachment/ticket/2052/RA5.0_16kbps_voice_wideband.ra

C:\>ffmpeg -i RA5.0_16kbps_voice_wideband.ra -f null -
ffmpeg version N-48116-g2e6bd22 Copyright (c) 2000-2012 the FFmpeg developers
  built on Dec 23 2012 02:22:15 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-w32threads --enable-memalign-hack --enable-runtime-cpudetect
--enable-cross-compile --enable-static --disable-shared --extra-libs='-lws2_32 -
lwinmm -lpthread' --extra-cflags='--static -I/var/www/users/research/ffmpeg/snap
shots/build/include' --extra-ldflags='-static -L/var/www/users/research/ffmpeg/s
napshots/build/lib' --enable-bzlib --enable-zlib --enable-gpl --enable-version3
--enable-nonfree --enable-libx264 --enable-libspeex --enable-libtheora --enable-
libvorbis --enable-libfaac --enable-libxvid --enable-libopencore-amrnb --enable-
libopencore-amrwb --enable-libmp3lame --enable-libvpx --disable-decoder=libvpx
  libavutil      52. 12.100 / 52. 12.100
  libavcodec     54. 81.100 / 54. 81.100
  libavformat    54. 49.102 / 54. 49.102
  libavdevice    54.  3.102 / 54.  3.102
  libavfilter     3. 29.101 /  3. 29.101
  libswscale      2.  1.103 /  2.  1.103
  libswresample   0. 17.102 /  0. 17.102
  libpostproc    52.  2.100 / 52.  2.100
Truncating packet of size 160 to 28
[rm @ 0x1eeea80] Estimating duration from bitrate, this may be inaccurate
Input #0, rm, from 'RA5.0_16kbps_voice_wideband.ra':
  Metadata:
    title           :
    author          :
    copyright       :
    comment         :
  Duration: 00:00:30.29, bitrate: 16 kb/s
    Stream #0:0: Audio: sipr (sipr / 0x72706973), 16000 Hz, mono, flt, 16 kb/s
Output #0, null, to 'pipe:':
  Metadata:
    title           :
    author          :
    copyright       :
    comment         :
    encoder         : Lavf54.49.102
    Stream #0:0: Audio: pcm_s16le, 16000 Hz, mono, s16, 256 kb/s
Stream mapping:
  Stream #0:0 -> #0:0 (sipr -> pcm_s16le)
Press [q] to stop, [?] for help
Multiple frames in a packet from stream 0
[null @ 0x1ffc3a0] st:0 PTS: 900 DTS: 900 < 6301 invalid, clipping
[null @ 0x1ffc3a0] st:0 PTS: 1800 DTS: 1800 < 6302 invalid, clipping
[null @ 0x1ffc3a0] st:0 PTS: 2700 DTS: 2700 < 6303 invalid, clipping
[null @ 0x1ffc3a0] st:0 PTS: 3600 DTS: 3600 < 6304 invalid, clipping
[null @ 0x1ffc3a0] st:0 PTS: 4500 DTS: 4500 < 6305 invalid, clipping
[null @ 0x1ffc3a0] st:0 PTS: 5400 DTS: 5400 < 6306 invalid, clipping
[null @ 0x1ffc3a0] st:0 PTS: 6300 DTS: 6300 < 6307 invalid, clipping
[null @ 0x1ffc3a0] st:0 PTS: 1800 DTS: 1800 < 7201 invalid, clipping
[null @ 0x1ffc3a0] st:0 PTS: 2700 DTS: 2700 < 7202 invalid, clipping
[null @ 0x1ffc3a0] st:0 PTS: 3600 DTS: 3600 < 7203 invalid, clipping
[...]
[null @ 0x1ffc3a0] st:0 PTS: 341100 DTS: 341100 < 343804 invalid, clipping
[null @ 0x1ffc3a0] st:0 PTS: 342000 DTS: 342000 < 343805 invalid, clipping
[null @ 0x1ffc3a0] st:0 PTS: 342900 DTS: 342900 < 343806 invalid, clipping
[null @ 0x1ffc3a0] st:0 PTS: 343800 DTS: 343800 < 343807 invalid, clipping
[null @ 0x1ffc3a0] st:0 PTS: 339300 DTS: 339300 < 344701 invalid, clipping
[null @ 0x1ffc3a0] st:0 PTS: 340200 DTS: 340200 < 344702 invalid, clipping
[null @ 0x1ffc3a0] st:0 PTS: 341100 DTS: 341100 < 344703 invalid, clipping
[null @ 0x1ffc3a0] st:0 PTS: 342000 DTS: 342000 < 344704 invalid, clipping
[null @ 0x1ffc3a0] st:0 PTS: 342900 DTS: 342900 < 344705 invalid, clipping
[null @ 0x1ffc3a0] st:0 PTS: 343800 DTS: 343800 < 344706 invalid, clipping
[null @ 0x1ffc3a0] st:0 PTS: 344700 DTS: 344700 < 344707 invalid, clipping
[sipr @ 0x1eef420] Error processing packet: packet size (7) too small
Error while decoding stream #0:0: Error number -1 occurred
[null @ 0x1ffc3a0] st:0 PTS: 340200 DTS: 340200 < 345601 invalid, clipping
RA5.0_16kbps_voice_wideband.ra: Input/output error
size=       0kB time=00:00:03.85 bitrate=   0.0kbits/s
video:0kB audio:945kB subtitle:0 global headers:0kB muxing overhead -100.000000%

[Carl Eugen Hoyos]

Also reproducible with Audible files, this may also break seeking.

[Elon Musk]

Fixed in 40cf943714007d32308e445a9dc43894f6c9479f.

Audible AA files have no real support for seeking.