Bokehlicious Selfies • Hacker News Board

Re: Bokehlicious Selfies

#31

Post by dewey » Sat, Mar 28, 2020, 11:32 AM UTC

lsh wrote: post #30

website has no scrollbar??

Only works if you scroll while hovering over the "content" part of the website in the center.

Re: Bokehlicious Selfies

#32

Post by StavrosK » Sat, Mar 28, 2020, 12:00 PM UTC

mark-r wrote: post #13

I just discovered that Zoom teleconferencing software has the ability to detect the background and replace it with an arbitrary video in real time. I have no idea how they do it, but it's as impressive as heck.

They detect the face and then extrapolate the body. You can tell because hiding your face (or turning away) makes you background.

Re: Bokehlicious Selfies

#33

Post by kingkawn » Sat, Mar 28, 2020, 12:22 PM UTC

Ain’t no lens that would blur the front brim of her hat and her face is clear like that. Disregarding the nature of the optics you are emulating ruins the value of the effect

Re: Bokehlicious Selfies

#34

Post by Jaxan » Sat, Mar 28, 2020, 1:19 PM UTC

mark-r wrote: post #13

I just discovered that Zoom teleconferencing software has the ability to detect the background and replace it with an arbitrary video in real time. I have no idea how they do it, but it's as impressive as heck.

Skype, Jitsi and MS teams also have this feature for some time now.

Re: Bokehlicious Selfies

#35

Post by fulafel » Sat, Mar 28, 2020, 1:32 PM UTC

rezistik wrote: post #4

This is really cool, but it isn't bokeh, it's just blur.

Bokeh is a type of blur (that's what the original word stands for too). The most common image processing blur is gaussian blur. According to the article the author is using a type of blur that simulates bokeh.

Re: Bokehlicious Selfies

#36

Post by kyberias » Sat, Mar 28, 2020, 1:35 PM UTC

Page is broken with no scrollbar.

Re: Bokehlicious Selfies

#37

Post by amelius » Sat, Mar 28, 2020, 1:50 PM UTC

One problem with bokeh is that it disappears when you scale the image down. Perhaps this technique can help solve that (but I suppose there would be better ways to do this).

Anyway, the entire technique is also very easy to do manually with Photoshop.

Re: Bokehlicious Selfies

#38

Post by amelius » Sat, Mar 28, 2020, 1:51 PM UTC

tobr wrote: post #24

rezistik wrote: post #4

This is really cool, but it isn't bokeh, it's just blur.

It also isn’t a selfie!

Yes. This hints at a more interesting application of DL: modify a selfie such that it doesn't look like a selfie anymore.

Re: Bokehlicious Selfies

#39

Post by sabalaba » Sat, Mar 28, 2020, 1:58 PM UTC

mark-r wrote: post #13

I just discovered that Zoom teleconferencing software has the ability to detect the background and replace it with an arbitrary video in real time. I have no idea how they do it, but it's as impressive as heck.

It’s likely some type of segmentation network like Mask RCNN or SegNet. Look up Mask RCNN for some state of the art segmentation results. This stuff has been able to run on mobile phones in real time for years now.

Re: Bokehlicious Selfies

#40

Post by Derbasti » Sat, Mar 28, 2020, 2:00 PM UTC

To make the Gaussian blur look better, it needs to be applied to linear lightness, not to gamma-encoded colors, as it is done here. In reality, the blur is induced by the lens, on linear lightness, and only gamma-encoded afterwards.

The effect being that blurred colors mix wrongly, as you can see where the red from the flower mixes with the green. The transition looks wrong, and not how a lens would render it.