RabidHaMsTeR.Org

Hi all -

What a fantastic program R4 is. However, a bit daunting for me. I am trying to learn how to make a preset that will have a true lissajou figure in it. That is, I need to plot the left and right stereo audio signals (x-horizontal and y-vertical). Is this possible in R4? I see many presets with things that look a bit loke Lissajou patterns, but I am not sure that they are true (unadorned).

If something like this already exists, could someone point me to it and offer a little direction?

Thanx for you help!

Dave

I can't really answer your question, but I did a quick google and was wondering if I'm understanding your question right. Are lissajou figures kinda like the old fashioned beziers screen saver on Windows? Sounds like it could make for an interesting scene.

Hi

A Lissajous figure plots two changing signals each on the X and Y axes. In audio it is often used to display phase relationships in a stereo signal. For instance, if you had a stereo signal of 1000Hz in each channel and those signals were in phase, you would get a diagonal line in the display both signal would rise and fall at the same time). If the signals are 180 degrees OUT of Phase, then the figure would be a circle.

If the signals are not the same frequency, you get more interesting patterns: With signal such as 1000Hz and 500 Hz, you would get a type of fisgure eight. If you usem say 1000Hz and 499 hz, the you would get a figure eight the slowly rotates at 1 Hz...
With normal stereo signal, the effect cabn range from wild scribbling (fast, uncorrolated left and right channels) to slow, changing ovals and figure eights with more static low sounds.

This may be a more technical explaination than necessary. On an Old Skool oscilloscope it was very easy. One would attach the left channel to the x axis and the Right channel to the Y axis and off you go!

But you are right, the figure looks a little like the Belzier curves.

Perhaps R4 is more involved than I need (though it is just so beautiful!) I just need to plot the relationship of two signals on a cartesian plane... is this 2D request too simple for R4 or is it (or perhaps I) just too simple for R4?

Dave

high!

this is a little bit incorrect, because waveRight[512]/waveLeft[512]/specLeft[512]/specRight[512] is an arrays, which contains 512 values (waveRight[0] - 0hz, waveRight[511] - 22khz? ). so your changes will operate only with most higher available frequency. and i'm not sure is it possible to get true sound frequency value, not separated by frequency ranges.. so, if you will find any web resources about sound analysis, please, post a links - it can helps