Re: [Discuss-gnuradio] Raw sample storage format

[David Young]

On Thu, Mar 10, 2005 at 12:38:13AM +0000, Dan Gisselquist wrote:
> [snip snip]
> I'd personally place the name/description, date, and if_frequency 
> information  into optional header fields, call them "header packets", all 
> having a a  preamble such as:
> 
> uint16                Header packet type (such as 1 for name/description)
> uint16                Header packet length
> (whatever)    Header packet contents
> 
> That way, any program that processes the header can quickly scan through 
> all  of these packets to find any information it understands, while 
> skipping any  other information.  Better yet, extending this format is easy.
> 
> The one question I would have, however, is whether or not this format would 
> support recording data from multiple antennas at the same time?  Would the  
> format be limited to single data channels, or would it support multiple?  
> It's  also worth asking how important word alignment is in this 
> process--especially  since compilers like to align things to word 
> boundaries automatically.

The organization formerly known as the National Center for Supercomputing
Applications (NCSA) has a data format called Hierarchical Data Format
that may fit the bill.  It's commonly used to store scientific data-sets
where there may be multiple channels/dimensions to the data, multiple
representations, etc.  There are well-maintained, highly-portable
libraries for reading/writing the format.  The HDF format is extensible
and I *think* self-describing, FSVO of self-describing.  HDF might also
be overkill for SDR.  Just a thought.

Dave

-- 
David Young             OJC Technologies
address@hidden      Urbana, IL * (217) 278-3933