On Tue, Aug 24, 2010 at 01:49:09PM -0700, Phong Do wrote: > > Hello Tom, > > Can you explain me why should gr_peak_detector need negative inputs ?
If you use grep, you can find places in the code where it is used, and then answer your own question. > What about the variable "look ahead" ? I wrote in the last message that > "look ahead" has no function in gr_peak_detector. My guess is that look_ahead was a feature that turned out not to be needed to solve the problem at hand, but was accidentally left in the constructor. > Do you know how can I add this feature in peak detector ? Yes. Write the code that implements it. Eric > On Thu, Aug 12, 2010 at 8:26 AM, Phong Do <stadtwald...@yahoo.de> wrote: > > > > Hello, > > > > I'm working now with peak_detector block and find out that some functions > > don't really work. > > I've used the following 2 blocks: > > > > - Peak Detector (gr_peak_detector): the parameter "look ahead" seems have > > no > > function. I gave "look ahead" many values but the peak value did not > > change. > > I've seen in the gr_peak_detector_xx.cc that the variable d_look_ahead is > > called but it is not used in the main program. So I think the developer > > has > > forgotten this function. > > > > - Peak Detector 2 (gr_peak_detector2): in this block "look ahead" is used, > > but sometimes the peak detector freezes (output signal stops running in > > scope sink). > > I've changed the cpp code a little bit and it does not freeze anymore. But > > I'm not sure if the detector will work correctly after that. > > Here is what I've changed: > > original code: return tmp - 1; > > changed code: return tmp; > > > > Can anyone of the development team have a look at the 2 cpp ? > > > > best regards > > Phong Do > > Keep in mind that the gr_peak_detector actually expects negative > inputs. So if your signal goes from 0 to 100, adjust it so that it > goes from -100 to 0. > > Of course, I say "keep in mind" even though we probably haven't > provided any documentation in the code to that affect... > > Tom _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio