Opus encoder fails on eof

[Carl Eugen Hoyos]

The opus encoder starts looping on eof.

$ ./ffmpeg -i fate-suite/svq3/Vertical400kbit.sorenson3.mov -vn -c:a libopus -b:a 64k out.opus
ffmpeg version N-45010-g5e6439a Copyright (c) 2000-2012 the FFmpeg developers
  built on Oct  4 2012 00:24:37 with gcc 4.7 (SUSE Linux)
  configuration: --enable-gpl --enable-libopus
  libavutil      51. 73.101 / 51. 73.101
  libavcodec     54. 63.100 / 54. 63.100
  libavformat    54. 29.105 / 54. 29.105
  libavdevice    54.  3.100 / 54.  3.100
  libavfilter     3. 19.102 /  3. 19.102
  libswscale      2.  1.101 /  2.  1.101
  libswresample   0. 16.100 /  0. 16.100
  libpostproc    52.  1.100 / 52.  1.100
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x2e31280] max_analyze_duration 5000000 reached at 5000998
Guessed Channel Layout for  Input Stream #0.1 : mono
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'fate-suite/svq3/Vertical400kbit.sorenson3.mov':
  Metadata:
    creation_time   : 2001-03-20 16:17:18
    title           : Vertical Online SV3 Demo
    title-eng       : Vertical Online SV3 Demo
    artist          : Logan Kelsey
    artist-eng      : Logan Kelsey
    copyright       : © Vertical Online 2001
    copyright-eng   : © Vertical Online 2001
    encoder         : Sorenson Video 3
    encoder-eng     : Sorenson Video 3
  Duration: 00:00:43.57, start: 0.000000, bitrate: 580 kb/s
    Stream #0:0(eng): Video: svq3 (SVQ3 / 0x33515653), yuvj420p, 320x240, 391 kb/s, 30.02 fps, 30 tbr, 600 tbn, 600 tbc
    Metadata:
      creation_time   : 2001-03-20 16:17:18
      handler_name    : Apple Alias Data Handler
    Stream #0:1(eng): Audio: adpcm_ima_qt (ima4 / 0x34616D69), 44100 Hz, mono, s16, 176 kb/s
    Metadata:
      creation_time   : 2001-03-20 16:17:18
      handler_name    : Apple Alias Data Handler
Output #0, ogg, to 'out.opus':
  Metadata:
    encoder-eng     : Sorenson Video 3
    title           : Vertical Online SV3 Demo
    title-eng       : Vertical Online SV3 Demo
    artist          : Logan Kelsey
    artist-eng      : Logan Kelsey
    copyright       : © Vertical Online 2001
    copyright-eng   : © Vertical Online 2001
    encoder         : Lavf54.29.105
    Stream #0:0(eng): Audio: opus, 48000 Hz, mono, s16, 64 kb/s
    Metadata:
      creation_time   : 2001-03-20 16:17:18
      handler_name    : Apple Alias Data Handler
Stream mapping:
  Stream #0:1 -> #0:0 (adpcm_ima_qt -> libopus)
Press [q] to stop, [?] for help
Multiple frames in a packet from stream 1
Trying to remove 480 samples, but que empty56.3kbits/s
[libopus @ 0x2e39560] Trying to remove 480 samples, but que empty
    Last message repeated 911505 times
Trying to remove 480 samples, but que empty
[libopus @ 0x2e39560] Trying to remove 480 samples, but que empty
^C    Last message repeated 25332 times
Trying to remove 480 samples, but que empty
[libopus @ 0x2e39560] Trying to remove 480 samples, but que empty
^C    Last message repeated 32213 times
Trying to remove 480 samples, but que empty
[libopus @ 0x2e39560] Trying to remove 480 samples, but que empty
^C    Last message repeated 33491 times
Received signal 2: terminating.

(Pressed Ctrl-C several times.)