IFF ANIM: support decoding of Anim Brushes

[ami_stuff]

decodes correctly with CyberAnim:

​http://aminet.net/package/gfx/show/CyberAnim13

​https://raw.githubusercontent.com/sabberworm/node-iff-parser/master/doc/IFF_FORMS/ANIM/ANIM_brush.txt

D:\>ffmpegx -i D:\anim\Camera.AnBr out.avi
ffmpeg version N-79991-g86e493a 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. 24.100 / 55. 24.100
  libavcodec     57. 41.102 / 57. 41.102
  libavformat    57. 36.100 / 57. 36.100
  libavdevice    57.  0.101 / 57.  0.101
  libavfilter     6. 45.100 /  6. 45.100
  libswscale      4.  1.100 /  4.  1.100
  libswresample   2.  0.101 /  2.  0.101
  libpostproc    54.  0.100 / 54.  0.100
Input #0, iff, from 'D:\anim\Camera.AnBr':
  Duration: N/A, bitrate: N/A
    Stream #0:0: Video: iff_ilbm (ANIM / 0x4D494E41), pal8, 154x99, SAR 10:11 DA
R 140:99, 60 fps, 60 tbr, 60 tbn
File 'out.avi' already exists. Overwrite ? [y/N] y
[avi @ 0x424c760] Using AVStream.codec to pass codec parameters to muxers is dep
recated, use AVStream.codecpar instead.
Output #0, avi, to 'out.avi':
  Metadata:
    ISFT            : Lavf57.36.100
    Stream #0:0: Video: mpeg4 (FMP4 / 0x34504D46), yuv420p, 154x99 [SAR 10:11 DA
R 140:99], q=2-31, 200 kb/s, 60 fps, 60 tbn
    Metadata:
      encoder         : Lavc57.41.102 mpeg4
    Side data:
      cpb: bitrate max/min/avg: 0/0/200000 buffer size: 0 vbv_delay: -1
Stream mapping:
  Stream #0:0 -> #0:0 (iff_ilbm (iff) -> mpeg4 (native))
Press [q] to stop, [?] for help
frame=   33 fps=0.0 q=31.0 Lsize=      88kB time=00:00:00.70 bitrate=1024.1kbits
/s speed=73.5x
video:81kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing ov
erhead: 8.197593%

[ami_stuff]

also plays correctly with MultiShow

​http://www.randelshofer.ch/multishow/index.html

[Elon Musk]

Fixed in a5c5ae5ed855f65f33abf27ce2f5839e07c7c8e9.