(sorry Harry, I missed to CC the list) On 12/21/2011 03:29 AM, Harry van Haaren wrote: > Hey all, > > I've been writing a scope the last while, and I'm intrested in how other > people have approached plotting the data.
http://kokkinizita.linuxaudio.org/linuxaudio/downloads/yass-0.0.2.tar.bz2 or http://xoscope.sourceforge.net/ > Currently I'm taking every 50th sample, and drawing a line from the > previous sample to there, and so on. Not particulary neat. > So is there a resample, or smoothing of the samples, or how does one plot a > "smooth" waveform like Ardour / QTractor? IIRC ardour uses all audio samples and lets cairo do the scaling. > My other question is about RMS, is calculating it in its literal sense > best? It depends on the use-case. A traditional analog scope does that. Well, it is not true RMS but a low-pass filter. >Or perhaps only taking every 5th sample? Better take the min/max of all sample that fall on a single pixel on the time-axis and draw a box (actually a vertical line if x is the time-axis). > Resampling the signal from 44.1 or 48k to say 11025? I'm not really sure > which way to go. 11025? 25 (fps) (or actually: screen update-freq aka vblank-frequency) multiplied by the width of display in pixels is more appropriate. Cheers! robin _______________________________________________ Linux-audio-dev mailing list Linux-audio-dev@lists.linuxaudio.org http://lists.linuxaudio.org/listinfo/linux-audio-dev