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Comment by theoh | Hacker News Reader

I don't know for sure but the code may be derived from or related to Marc Levoy's SynthCam: https://sites.google.com/site/marclevoy/

It does similar things, and in fact I could believe it if the Google app was just a dumbed down version of the functionality intended to be usable by a wider audience.

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They did hire Marc Levoy. I have been hoping for this for awhile. Can't wait for the next iteration. There are certain things you can't replicate with just a single tiny camera, but they are doing a great job! https://news.ycombinator.com/item?id=6483182

> There are certain things you can't replicate with just a single tiny camera

MOST DoF and bokeh effects in photography can't be replicated with a single small camera.

As a photographer, bokeh is surprisingly difficult to fake, and looks glaringly bad when you notice. The blur effect is due to focal distance ratio differences, and it's very difficult to determine the distance in software. Hell, it's hard to determine it with 2 lenses, as the HTC implementation does.

If you want to compare what "fake bokeh" looks like compared to real stuff, you can look at http://www.trustedreviews.com/opinions/htc-one-m8-camera-vs-... for a review of the HTC One M8, which has a 2-lens setup.

Look at this picture, for example: http://static.trustedreviews.com/94/00002b836/8517/blue-htc-... For most software, it's extremely difficult, even with distance data, to separate the bush in the back from the blue toy. As a result... messy looking blur.

I look forward to a review of this software vs HTC vs dSLR. My first instinct is this is much less artificial.

Very true. We do this kind of work in VFX all the time to reduce CG rendering costs for blurs that are expensive in 3d but cheap in 2d. Even with access to sub pixel (4x, 8x etc.) depth maps there are always lots of issues to deal with around edges.

But given that jpeg is good enough for most people I'm sure these types of tools are too.

Unfortunately, as a non-professional photographer, I think this article very disingenuous. Most of the shots aren't taken from the same distance, angle, nor lighting. "Here we are, closer to the subject and from a different angle; notice that we don't have to deal with distinguishing our focused subject from subjects that no longer exist!" "Sure these look the same, but this one is done with optics and is definitely better!"

While it is unfortunate that they did not do the exact angle in all shots, it is still possible to see the difference in the simulated and real effects.

I can say that, as a non-professional photographer, picking up a prime lens and using that for the family shots has been an extremely eye opening experience. To the point that I actually dislike most photos from point and shoots.

There is definitely a bit of "quit caring about aperture." And I can't argue against progress in making the phone cameras better. I'm just not seeing compelling evidence to ditch my DSLR.

They're clearly taken with the same lightning (outdoors and around the same time), but with different iso/aperture/exposure -- as they would have to be. The dedicated camera will let in much more light than the phone camera.

I do agree the zoom/distancing on the "foliage" photos are unfortunate for comparison -- but the fluffy animals more than make up for it IMNHO.

According to the article, and my own experience with google's version, it's good enough for simple portraits. Since most photos, and close to 100% of photos anybody actually cares about, are portraits that makes it a pretty useful feature.

There have been multiple implementations of this class of algorithm (collectively "synthetic aperture") using different techniques.

Edit: below mentions the HTC "double camera" phones, and in fact it's also possible to create synthetic aperture photography with multiple cameras instead of moving a single camera to multiple positions. Then you have the added advantage of not needing to assume a static scene! But a single-camera algorithm is great for rolling out to the common devices most of us have in our pockets.

Marc Levoy's SynthCam used a circular wiping motion, and attempted to "paint" the 3d space occupied by your theoretical processed aperture.

This Google Camera only requires a single linear move, and processes the rest!

It looks like this isn't creating a synthetic aperture, it's just creating a depth map and applying a depth-dependent blur to a single frame.

According to the text the blur itself is simulating an actual lens. Without seeing the exact algorithm it's hard to know how accurate that claim is. There are many ways to do a blur and I know what I'd use if I were trying to generate good bokeh.

Point taken. Arguably it's a case of David Pye's notion of the workmanship of certainty (in this case heavy-lifting computer vision) replacing the workmanship of risk (making adept movements of camera) But if it works better under all conditions, fine. http://en.m.wikipedia.org/wiki/David_Pye_(furniture)

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