By red I mean a RGB value (0.5, 0, 0). ++ Jack
Le 24/10/2017 à 19:07, Jack a écrit : > OK, I tested your patch and on my side, i get a solid red square. No > flicker. > ++ > > Jack > > > > Le 24/10/2017 à 18:33, Jack a écrit : >> Hello, >> >> Le 24/10/2017 à 11:24, Peter P. a écrit : >>> * cyrille henry <c...@chnry.net> [2017-10-24 13:32]: >>>> >>>> >>>> Le 24/10/2017 à 13:18, Peter P. a écrit : >>>>> Hi list, >>>>> >>>>> I am trying to convert an audio signal to pixel data using pix_sig2pix~ >>>>> and then back to audio data using pix_pix2sig~ without further >>>>> manipulations. Please see attached patch. >>>>> >>>>> I do scale the audio signal from -1 to 1 to lie in a range compliant >>>>> to pixel data, which I assume to be 0 to 1. >>>>> >>>>> Not having connected an input to the subpatch, this signal will hence be >>>>> 0.5 and will display in the red color channel. >>>>> >>>>> Converting that red channel back to audio signals and doing the opposite >>>>> scaling operation, I am getting a 51dB constant signal at the output >>>>> even without having attached a signal to the input of pix_sig2pix~. >>>>> Checking with a snapshot~ object indicates a constant signal of 0.003921 >>>>> >>>>> I assume this to be due to limited resolution numbers in the pixel data >>>>> and wonder what their resolution is? >>>> >>>> 8 bits / channels >>>> >>>> so resolution is 1/256 = 0.0039... >>>> >>>> You can code MSB in Red, and LSB in green is you want 16 bits... >>>> >>>>> >>>>> Then I texture the pixel data onto a rectangle. This rectangle >>>>> does flicker and flip diagonally from time to time and I wonder if it is >>>>> an error on my machine only and where it could come from. >>>> >>>> I don't see any flicker in your patch. (linux / intel GPU) >>> >>> Thank you Cyrille for this helpful information! >>> >>> Jack, I am on Debian GNU/Linux with an onboard Intel graphics controller >>> (i915 variant). >> >> OK, i guessed you were on nvidia because if you are not sync to vblank, >> you often get a line diagonaly separating two pictures. It is called >> "screen tearing". >> I didn't test your patch yet... >> ++ >> >> Jack >> >> >>> >>> P >>> >>> _______________________________________________ >>> Pd-list@lists.iem.at mailing list >>> UNSUBSCRIBE and account-management -> >>> https://lists.puredata.info/listinfo/pd-list >>> >> >> >> _______________________________________________ >> Pd-list@lists.iem.at mailing list >> UNSUBSCRIBE and account-management -> >> https://lists.puredata.info/listinfo/pd-list >> > > > _______________________________________________ > Pd-list@lists.iem.at mailing list > UNSUBSCRIBE and account-management -> > https://lists.puredata.info/listinfo/pd-list > _______________________________________________ Pd-list@lists.iem.at mailing list UNSUBSCRIBE and account-management -> https://lists.puredata.info/listinfo/pd-list