Thanks for the recommendations. I should clarify that I am a software engineer, not a signals engineer, and my recurring need to visualize time-series data is often satisfied without having to invoke DSP. An example of the sort of thing I frequently want to do is to interactively explore data collected from multiple wireless sensors (e.g., six months of temperature and humidity data collected at 1-minute intervals). Technically signals, but simple shifts, scales, and basic windowed statistics are more useful than FFTs and complex filters.
Sometimes I do need DSP techniques to extract the data from third-party wireless transmissions, hence my current dabbling with GNU Radio, but it's the data not the extraction process that's the primary focus. For example, the reason I'm using GNU Radio is my need to demodulate packets from a WS-2080 Weather Station and some other 433 MHz OOK sensors. Yes, I've tried rtl433 and rtlsdr-433m-sensor; the signal I'm capturing is too noisy or I don't have frequency/bandwidth/filter settings right. The specific use case that introduced my question about analysis tools is my desire to interactively identify regions of interest from wideband captures and then re-play that data repeatedly through various processing chains, tweaking parameters until I get something that reliably produces the underlying data. @mossman: The GSoC project is very close to what I'd want for DSP-oriented analysis. If it existed it'd probably handle the motivating example above. It's too domain-specific for generalized time-series visualization, though, so I'd still have an unmet need. @marcus.mueller: Thanks for the details. My experience is that a metered stream/dataflow-oriented architecture is simply unsuited to the sort of offline analysis I'm trying to do. The ability to jump forwards and backwards in time is crucial, as is the ability to decouple the signal rate from the data processing rate. Example: Qt Time Raster schedules its updates based on wall clock not sample time, so speeding up or slowing down the rate of data through the system changes the displayed images, and running unthrottled drops all the information. @dan.cajacob: pandas reminds me a lot of R. The intro video showed it'd be good for CLI-based data manipulation, but my initial need is to explore data graphically. @mdammer: kst-plot's web site shows some promising graphs, and it built cleanly (though it doesn't obey CMAKE_INSTALL_PREFIX), but I've been unable to locate examples and documentation that would allow me to evaluate its capabilities quickly. @madengr: Lack of source code for baudline and its focus on DSP knocks it out of contention for my general needs. On 07/16/2014 09:52 AM, Peter A. Bigot wrote:
The sort of capabilities I'm looking for include: Read time-series data from files of different formats (some too large to fit in physical memory). Display the data, optionally applying linear transformations. Interactively pan and zoom. Jump forwards and backwards among time-registered events. Enable/disable/time-shift data overlays. Export selected data to new files. Calculate and display statistics and other non-linear transformations of selected data.
A rough course towards the tool I imagine would be: * Collect/develop a suite of Qt/C++ widgets for graphical data display and manipulation that are not sensitive to the processing rate, don't have a unidirectional concept of time, can be accessed from Python, and can be combined to build something with the capabilities listed above. * Use a command-line interface like pandas/R to display original files, extract regions of interest, apply transformations, and repeat until satori. * Use GNU Radio Companion to glue components together to form domain-specific analysis applications. That's a lot of yak shaving just to get a reliable OOK packet extractor, so it probably won't happen. Thanks again for the suggestions. Peter _______________________________________________ Discuss-gnuradio mailing list [email protected] https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
