[sigrok-devel] How to slice up an existing session?

[Angus G. <gu...@pr...>]

Does sigrok include tools to slice up an existing debug session, ie
extract a subset of samples?

This is a problem I'm particularly sensitive to as I'm using fx2lafw
to take long-running captures of debugger sessions, but then only
really wanting to look at a few events out of thousands.

I've looked on the wiki but I might be searching the wrong terms (in
which case I apologise in advance for inadequate RTFM.)

I also noticed sigrok-cli's --samples option doesn't seem to do
anything if reading from a session, so you can't use something like:

sigrok-cli -i new.sr --samples 250k <blah>

to limit the number of samples you read from the session.


If there isn't an easy way to do this at the moment, I was thinking I
could look at implementing it in sigrok-cli as follows:

* amend the --samples option so it works when reading from a session file.

* Add a --skip-samples option that skips N samples from the beginning
  of the capture (or after triggering if a trigger point is
  specified).

So then you can do something like:

sigrok-cli -i new.sr -o subset.sr --samples 1k --skip-samples 100k

To extract 1000 samples from 100000 samples into the capture.

* Possibly even a --skip-time option would be useful, so you can
  extract a subset by looking at timestamps in pulseview.

Does this sound useful, or would it be totally redundant?


Angus