Re:IP Over QR Code
by ChuckMcM on Saturday November 19, 2016 @02:48PM
(#12995236)
That is an awesome project, much better than the QR Clock I did.
My experience with the clock was that I really needed ECC mode 'M' to get the maximum ECC bits which worked around all sorts off issues with differences in scan rates between display and reader.
In my setup the QR clock is displayed on an array of 64 x 64 LEDs, when the LEDs were operating at a 60hz refresh rate you could induce some pretty interesting interference with the camera scan rate on phones with QR readers, once I boosted the refresh rate to 240 hz that interference went away, then it was a question of how much "dwell time" did the code need to be recognized and I got it down to 100mS as the fastest I could go and the QR libraries on the iPhone and Android could still pick it up.
So for reliability considerations maximize the display refresh rate and the ECC correction level.
My experience with the clock was that I really needed ECC mode 'M' to get the maximum ECC bits which worked around all sorts off issues with differences in scan rates between display and reader.
In my setup the QR clock is displayed on an array of 64 x 64 LEDs, when the LEDs were operating at a 60hz refresh rate you could induce some pretty interesting interference with the camera scan rate on phones with QR readers, once I boosted the refresh rate to 240 hz that interference went away, then it was a question of how much "dwell time" did the code need to be recognized and I got it down to 100mS as the fastest I could go and the QR libraries on the iPhone and Android could still pick it up.
So for reliability considerations maximize the display refresh rate and the ECC correction level.