Hi,<div><br></div><div>When I&#39;m programming, I find it immensely helpful to be able to plot audio data at different points in its processing, for debugging, and to test new ideas.</div><div><br></div><div>Essentially I want an oscilloscope, which plots each chunk of 1024 samples.</div>

<div><br></div><div>I&#39;ve tried using libplot, but it seems too slow.  It&#39;s causing constant xruns, even when I only plot every 5th sample.</div><div><br></div><div>I thought that maybe libplot was too abstract, and that I needed to draw the pixels on the screen directly.  I tried using SDL, but it caused excessive xruns also.  Simply setting 48000 pixels per second was enough to cause the flow of xruns.  This is  *not* erasing the screen, just drawing the points.  I&#39;d expect that erasing the screen is the slow part, but apparently not.</div>

<div><br></div><div>At this point I&#39;m not sure if it&#39;s even possible to plot the audio data in realtime.  I did a rough calculation, that on my 2 Ghz cpu, it should have roughly 40,000 cycles to process each sample.  It seems to me that considering running the whole plugin only uses 1/4 of my cpu, the other 30000 cycles should be plenty to put a pixel on the screen.</div>

<div><br></div><div>So I would guess that something else is the bottleneck, like my video chip, or maybe the libraries I&#39;m using.</div><div><br></div><div>So basically my question is:  Has anyone else had any luck with plotting audio data in real time, and if so, how?  Is it not possible to plot every sample, but only a certain percentage of them?  Is there a fundamental restriction on doing so, or is my problem in software?</div>

<div><br></div><div>Jeremy</div>