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 Xmas receiver mathematical insights bulligan Junior Member Posts: 4 Threads: 1 Joined: May 2023 Institution: Torricelli 05-12-2023, 09:46 AM (05-05-2023, 06:08 PM)Jens Noritzsch Wrote: Technically, https://phyphox.org/xmas/ already provides most of the information: the general principle is explained and the .phyphox file is open source (see https://phyphox.org/wiki/index.php/Phyphox_file_format). I try to break it down a bit. The audio file plays four concurrent notes, one each in the ranges [749…2249] (x coordinate), [2249…3749] (y coordinate), [3749…5249] (color and repeat), and [5249…5624] (checksum) Hertz. Each segment is divided into subranges of the width 48000/2048=23.4375 Hz. On each of these range a FFT is mapped and in each the maximum is searched. If the maximum of the first range is in the nx-th segment, then the x coordinate is this nx (1…64). If the maximum of the second range is in the ny-th segment, then the y coordinate is this ny (1…64). If the maximum of the third range is in the n-th segment, then the remainder of n divided by 8 gives the color (0…7) and the quotient of n divided by 8 (the integer part of n/8) tells how often the point should be repeated in x direction (internally we add one, so 1…8 is the possible length of the horizontal block in the graph). If the maximum of the forth range is in the c-th segment, then the remainder of (nx+ny+n) divided by 16 needs to match c–1 (0…15) or the entire point is discarded. HTH a bit. Thanks, i'll start from this. I have the idea of trying to use the generator and analyze the spectrum of the .wav file when encrypting RGB images (for example: completely white or green or blue or red or green) to see how it works. « Next Oldest | Next Newest »

 Messages In This Thread Xmas receiver mathematical insights - by bulligan - 05-05-2023, 09:53 AM RE: Xmas receiver mathematical insights - by Jens Noriʇzsɔɥ - 05-05-2023, 06:08 PM RE: Xmas receiver mathematical insights - by bulligan - 05-12-2023, 09:46 AM RE: Xmas receiver mathematical insights - by Jens Noriʇzsɔɥ - 05-05-2023, 06:11 PM RE: Xmas receiver mathematical insights - by Jens Noriʇzsɔɥ - 05-12-2023, 10:17 AM RE: Xmas receiver mathematical insights - by bulligan - 05-15-2023, 12:10 PM RE: Xmas receiver mathematical insights - by Jens Noriʇzsɔɥ - 05-15-2023, 02:25 PM RE: Xmas receiver mathematical insights - by bulligan - 05-22-2023, 06:40 PM

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