4 ms·

I wonder what throughput it can give when used as an animated sequence of codes? I experimented with animated QRs for data transfer last week and the real maxim

by divan 8y ago

I wonder what throughput it can give when used as an animated sequence of codes? I experimented with animated QRs for data transfer last week and the real maximum I’ve achieved was around 9KB/s. https://divan.github.io/posts/animatedqr https://divan.github.io/posts/animatedqr Using colored high-capacity encoding should yield much better results, given the decoder is as fast as QR one.

specialist 8y ago
Cool. How does Apple's iPhone-to-Watch pairing animated graphic work? Maybe their technique has higher bandwidth.
- divan 8y ago
  Unlikely. I skimmed through both patents [1][2], and I don't recall any numbers on throughput. But the general principle is super cool – they analyze the change in luminance of the picture, and chrominance can be whatever you wish (so they can replace particle cloud with any custom animation). The idea is that human eye is much more perceptible to changes in color than to changes in luminance, but for image processing software it's quite different - they can decode luminance changes quite reliably :) So my guess is that Apple's approach is optimized for coolness, rather than transfer speed. [1] http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&u=%2Fnetahtml%2FPTO%2Fsearch-adv.htm&r=2&p=1&f=G&l=50&d=PTXT&S1=(235%2F469.CCLS.+AND+20150505.PD.)&OS=ccl/235/469+and+isd/5/5/2015&RS=(CCL/235/469+AND+ISD/20150505) http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=H... [2] http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&u=%2Fnetahtml%2FPTO%2Fsearch-adv.htm&r=1&p=1&f=G&l=50&d=PTXT&S1=(235%2F469.CCLS.+AND+20150505.PD.)&OS=ccl/235/469+and+isd/5/5/2015&RS=(CCL/235/469+AND+ISD/20150505) http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=H...
- paulgb 8y ago
  Speaking of screen-to-watch data transfer, the Timex Data Link watch somehow accomplished this in the mid-90s. There must have been some dark magic to make it work on a watch-battery powered processor at the time. https://youtu.be/2VmtPaiOBwI https://youtu.be/2VmtPaiOBwI
  - divan 8y ago
    That’s definitely a dark magic! Thanks for sharing this.
deathanatos 8y ago
Neat! I've always been a fan of these "low-tech" (not involving complicated radio protocols like Bluetooth that inevitably seem to never work) transmission protocols. I kinda wish something like what you built was more widely supported, so I could transfer files between my phone and OS X. (Which both have Bluetooth, yet it never works. So I upload to Drive.) Similarly, but with audio[1]: http://www.whence.com/minimodem/ http://www.whence.com/minimodem/ [1]: (and yes, I know this is how it "used" to be done / I am old enough to remember it.)
klohto 8y ago
What if you used high capacity code like HCCB or CQR Code-9. CQR has a capacity of 3KB per square inch [1], based on your formula of 11 frames per second, you could easily do 33KB/s. And that is just a square inch, I think you could reach pretty good transfer speeds with higher resolution and wider dimensions. [1] - https://pdfs.semanticscholar.org/95c7/fe455a084b0f0ce9923e996652156c1f7998.pdf https://pdfs.semanticscholar.org/95c7/fe455a084b0f0ce9923e99...

by divan 8y ago

specialist 8y ago

Cool. How does Apple's iPhone-to-Watch pairing animated graphic work? Maybe their technique has higher bandwidth.

divan 8y ago
Unlikely. I skimmed through both patents [1][2], and I don't recall any numbers on throughput. But the general principle is super cool – they analyze the change in luminance of the picture, and chrominance can be whatever you wish (so they can replace particle cloud with any custom animation). The idea is that human eye is much more perceptible to changes in color than to changes in luminance, but for image processing software it's quite different - they can decode luminance changes quite reliably :) So my guess is that Apple's approach is optimized for coolness, rather than transfer speed. [1] http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&u=%2Fnetahtml%2FPTO%2Fsearch-adv.htm&r=2&p=1&f=G&l=50&d=PTXT&S1=(235%2F469.CCLS.+AND+20150505.PD.)&OS=ccl/235/469+and+isd/5/5/2015&RS=(CCL/235/469+AND+ISD/20150505) http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=H... [2] http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&u=%2Fnetahtml%2FPTO%2Fsearch-adv.htm&r=1&p=1&f=G&l=50&d=PTXT&S1=(235%2F469.CCLS.+AND+20150505.PD.)&OS=ccl/235/469+and+isd/5/5/2015&RS=(CCL/235/469+AND+ISD/20150505) http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=H...
paulgb 8y ago
Speaking of screen-to-watch data transfer, the Timex Data Link watch somehow accomplished this in the mid-90s. There must have been some dark magic to make it work on a watch-battery powered processor at the time. https://youtu.be/2VmtPaiOBwI https://youtu.be/2VmtPaiOBwI
- divan 8y ago
  That’s definitely a dark magic! Thanks for sharing this.

deathanatos 8y ago

Neat! I've always been a fan of these "low-tech" (not involving complicated radio protocols like Bluetooth that inevitably seem to never work) transmission protocols. I kinda wish something like what you built was more widely supported, so I could transfer files between my phone and OS X. (Which both have Bluetooth, yet it never works. So I upload to Drive.) Similarly, but with audio[1]: http://www.whence.com/minimodem/ http://www.whence.com/minimodem/ [1]: (and yes, I know this is how it "used" to be done / I am old enough to remember it.)

klohto 8y ago

What if you used high capacity code like HCCB or CQR Code-9. CQR has a capacity of 3KB per square inch [1], based on your formula of 11 frames per second, you could easily do 33KB/s. And that is just a square inch, I think you could reach pretty good transfer speeds with higher resolution and wider dimensions. [1] - https://pdfs.semanticscholar.org/95c7/fe455a084b0f0ce9923e996652156c1f7998.pdf https://pdfs.semanticscholar.org/95c7/fe455a084b0f0ce9923e99...