freeMXF.org

Open discussion about freeMXF.org tools and MXF in general
It is currently Tue Jul 23, 2019 11:29 pm
Board index » MXF Categories » MXF Clarifications



Post new topic Reply to topic  [ 3 posts ] 
Author
Search for:
Message

Offline
Rookie

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

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

 Profile  

Offline
Insider

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

Post Posted: Wed Apr 20, 2011 7:59 am 
Top  
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.

 Profile WWW  

Offline
Rookie

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

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

 Profile  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 3 posts ] 

Jump to:  


Who is online

Users browsing this forum: No registered users and 1 guest

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum
cron
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group :: Style based on FI Subice by phpBBservice.nl :: All times are UTC