How do I make REACTIVE LED LIGHT STRIPS

Other Hardware LEDs and Multiplexing
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I want this effect: RGB LED Strips controlled by IR sensors (Arduino) - YouTube

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scarcityoutlook:
I want this effect: https://m.youtube.com/watch?v=SbovbL4UM4A&time_continue=21&ebc=ANyPxKqw9CvDqZUde61JozFJUP_vt05g4i1HqYD6AGI4P1b5xdnGSgu7o3my3BovGLWz-Limj3IVbEBLXZjupw8D4NVISgNZ2w

There is a link on that youtube page http://legacy.andrewflo.com/work/infrared-midi-controller/ . Maybe look there first?