Re: [Discuss-gnuradio] timestamp in saved data

[Eric Blossom]

On Tue, Sep 19, 2006 at 06:04:15PM -0400, Chuck Swiger wrote:
> On Tue, 2006-09-19 at 13:28 -0400, Charles Swiger wrote:
> > On Tue, 2006-09-19 at 11:45 -0400, Charles Swiger wrote:
> > > I just used Jim Cooley's file headers to put timestamps in my
> > > shortwave radio data so when I play back a pirate radio broadcast
> > > I can see that, hey, that was on last Saturday at 8:15PM. The
> > > gui now sports a clock showing either current or playback time.
> > > 
> > > gr.file_hdr_sink|source seem pretty flexible, just an arbitrary
> > > length of int's that can mean anything you want to define. Anyway,
> > 
> > Oh well - unfortunately, it's a case of gaining on thing, metadata, but
> > losing another, the ability to SEEK around in the data file!
> > 
> 
> Actually, best I can do with header timestamps is a 'fast forward' by
> connecting the file src to a null_sink, that does about a minute every 3
> seconds ;)    Rewind is still impossible, but de-headering to raw data
> is easy.
> 
> --Chuck

Chuck,

gr.file_source has a seek method which will allow you to seek
instantly anywhere in the file.  

[Actually, I note that it's defined with a long instead of int64_t
offset, so to move more than 4GB, you have to do it in multiple steps]

Eric