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Joined: Mon Apr 18, 2011 11:57 am
Posts: 2
Location: UK

Post Posted: Mon Apr 18, 2011 12:20 pm 
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Hi

As far I know, all variables lengths in MXF are BER encoded.

That's why when reading length for "Index Entry Array" was finding it through BER function.

It all have been working fine, but recently have issues with few files, where first byte of length is 0x80, which I suppose is wrong.

Also mentioned by code line
http://www.koders.com/cpp/fid6A7143C828AF1376B7DCBF5072F5AF2FE5E8783B.aspx?s=mdef%3Ainsert#L142

I want to know, what is correct way to read length of "Index Entry Array" either to find it using BER method or by reading just 2 bytes. If I read only 2 bytes after 0x3F0A everything works fine again.

Thanks a lot

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Joined: Thu Apr 15, 2004 10:39 am
Posts: 198
Location: Scotland

Post Posted: Wed Apr 20, 2011 7:59 am 
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Lengths of sets and packs are coded using BER lengths, but generally all lengths within MXF sets are 2-byte values (MSByte first).

There is provision in 377-1-2009 to encode some sets to use BER lengths internally, but this is best avoided as there are some strict requirements to use it and most implementations do not support it.

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Post Posted: Wed Apr 20, 2011 8:51 am 
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Thanks

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