how to install new codec for video?

[twd]

How do I install a new codec for a video stream type not
already supported.

The playlist item info on the file I am trying to use
says that the stream: 0 Type: video has a
Codec: undf.

It shows the resolution of 672x288 and frame rate
of 30.0 fps.

All the other info on the other tracks/stream
components are absolutely correct (like the Audio).

I need to make this undefined video codec known to VLC.

The info I have from my MatroskaDiag v1.0.0.62 shows that
I need to use the following codec which I have installed
in C:\Program Files\LD-Anime\MKV\RealMediaSplitter.ax
but it is unknown to VLC.

Any ideas on how to make this video codec known to VLC?

Thanks!
-twd

===============
File size : 688.90 MB
File complete : yes
Duration : 02:15:50.607
Title : Matroska Test File
Writing application : mkvmerge v0.9.3 built on Jul 18 2004 18:24:15
Muxing application : libebml v0.7.0 + libmatroska v0.7.0
Date : 2003-07-23 16:45:22.000
Tracks : 4

Track 1 : Video

Codec : RealVideo 9/10 (V_REAL/RV40)
Possible filter : RealMedia Splitter/Decoder
Installed : yes, in C:\Program Files\LD-Anime\MKV\RealMediaSplitter.ax (1.0.1.0)
Install comments : You also need to install RealPlayer One or RealAlternative.
Link : http://sourceforge.net/projects/guliverkli
Name : Matroska Test File RealVideo 9
Language : English (eng)
Pixel Width : 672
Pixel Height : 288

Track 2 : Audio

Codec : Vorbis (A_VORBIS)
Possible filter : CoreVorbis
Installed : yes, in C:\Program Files\LD-Anime\CoreVorbis.ax (1.1.0.79)
Link : http://corevorbis.corecodec.org
Name : Audio English
Language : English (eng)
Sampling Frequency : 48000
Channels : 2

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