Hello trid users,
some days ago i handle some video files. I run TrID on VirtualDub links with
file name extension vdr and related videos.
All VDR samples are described correctly as Generic RIFF container by
riff.trid.xml ( see appended output/trid-v-old.txt), but sub type
classification is missing.
The newest file(1) command describes such CDR examples as VirtualDub link
(see appended output/file-new.txt).
All such inspected VDR samples are RIF containers. This is expressed by XML
construct like:
<Bytes>52494646</Bytes>
<ASCII> R I F F</ASCII>
<Pos>0</Pos>
Some information about such VirtualDub links is found on file formats
archive team website. That is now expressed by line like:
<RefURL>
https://fileinfo.com/extension/vdr</RefURL>
According to documentation the second RIFF tag for VirtualDub link
is VDRM. After that characteristic string comes the up cased phrase PATH,
that is followed by pascal string with remote-path to video file.
That information is shown by XML construct like:
<Bytes>00005644524D50415448</Bytes>
<ASCII> . . V D R M P A T H</ASCII>
<Pos>6</Pos>
The size of PATH is stored as 4 byte integer at offset 16. Because of file
system limitation the high values could never appear. So assuming a possible
maximal value 65535 for path gives 2 null upper bytes. That is expressed by
XML construct like:
<Bytes>0000</Bytes>
<Pos>18</Pos>
A user defined mime type is shown by line like:
<Mime>video/x-vdr</Mime>
With the new definition files the VirtualDub links are now recognized ( see
appended output/trid-v-new.txt). TrID definition, some examples and output
are stored in archive vdr.zip. I hope that my XML file can be used in future
version of triddefs.
With best wishes
Jörg Jenderek
