If you mean binary files saved by Origin itself (.opj, ogw, ...), I believe no description of such is available publicly. Or, that about general binary file format is really a topic too big to describe in details.
QtiPlot can import data saved by Origin, once, the old format. You may try to see how it works. The new format supports multiple sheets. Whether this is supported or not by QtiPlot, I don't know (it's been some time since my last time using it...). If you are working on Windows, there is Orglab for you: http://blog.originlab.com/2014/new-orglab-methods.
PS: it's said that there's a new format coming, see http://www.originlab.com/forum/topic.asp?TOPIC_ID=20085.
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Origin binary format
Posted - 02/16/2015 : 4:00:44 PM
