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Lens Blur in the new Google Camera app

googleresearch.blogspot.com

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Re: Lens Blur in the new Google Camera app

#141

Post by coldtea »

grecy wrote: post #132
acjohnson55 wrote: post #125

Earlier quoted context omitted.

Those permitted edits you mention seem to all preserve the pixel-level integrity of the image. The fact that intentional blurring does not do this seems to be a distinction to me. I think that the fact that the blur layer must be synthesized heuristically indicates that not all of the information of the final image was really captured from the real world. I suppose that resizing (resampling) an image might be said to…

>Those permitted edits you mention seem to all preserve the pixel-level integrity of the image. Curiously, you're allowed to convert color to black and white, which in my opinion is not preserving the pixel-level integrity. An algorithm is making a guess at what level of black to convert a pixel to. > Question for professionals -- how are noise reduction, masks (unsharp), etc. treated? I'm not a pro yet, but my under…

Huh? Noise reduction is not a no no by any means. At least in some newspapers I know.

Also, I have to add that it differs for news reporting versus stuff like interview shots, travel shots etc.

Re: Lens Blur in the new Google Camera app

#142

Post by ISL »

ISL wrote: post #46
apu wrote: post #21

Earlier quoted context omitted.

Lytro is also "just" simulating it, but with slightly more/different data. They capture a light field but that doesn't magically give them depth values; they have to estimate them using an optimization, and then render the final image using a very similar algorithm.

Edit: Whoops: I mis-read the article; 'Lens Blur' uses multiple frames. That lets you get a lot more information.

Well, The Lytro will still win on moving subjects where a sequence convolves subject motion with the depth map.

Re: Lens Blur in the new Google Camera app

#143

Post by dharma1 »

the accurate depth map creation from 2 photos on a mobile device is impressive. The rest has been done many times before

This is cool, but I am waiting more for RAW images exposed in Android camera API. Will be awesome to do some cutting edge tonemapping on 12bits of dynamic range that the sensor gives, which is currently lost.

Re: Lens Blur in the new Google Camera app

#145

Post by grecy »

coldtea wrote: post #141
grecy wrote: post #132

Earlier quoted context omitted.

>Those permitted edits you mention seem to all preserve the pixel-level integrity of the image. Curiously, you're allowed to convert color to black and white, which in my opinion is not preserving the pixel-level integrity. An algorithm is making a guess at what level of black to convert a pixel to. > Question for professionals -- how are noise reduction, masks (unsharp), etc. treated? I'm not a pro yet, but my under…

Huh? Noise reduction is not a no no by any means. At least in some newspapers I know. Also, I have to add that it differs for news reporting versus stuff like interview shots, travel shots etc.

> Also, I have to add that it differs for news reporting versus stuff like interview shots, travel shots etc.

Right, it really depends on if the shot is being used for "news" or if it's just an artistic shot to fill space.

That's why at the start of this whole thread I reference photojournalism.

Re: Lens Blur in the new Google Camera app

#146

Post by timbre »

DangerousPie wrote: post #70

Isn't this just a copy of Nokia's Refocus? https://refocus.nokia.com/ edit - better link: http://www.engadget.com/2014/03/14/nokia-refocus-camera-app-...

The method at least is very different. The Google app is doing structure from motion, which essentially uses parallax to get the 3D shape of the scene. From there, you can blur/deblur according to depth. The Nokia app uses focal sweep, i.e. it just takes lots of pictures of the same scene focussed at different depths. I'm not sure what the pros and cons of each approach are.

Re: Lens Blur in the new Google Camera app

#148

Post by sjtrny »

nileshtrivedi wrote: post #130

With these algorithms, will it become feasible to make a driverless car that doesn't need a LIDAR and can run with just a few cameras? Currently, the cost of LIDARs are prohibitive to make (or even experiment with) a DIY self-driving car.

In the future maybe. Computing the depth maps in this simple case is not very costly because it only requires a relatively sparse amount of key points. To recreate the full scene geometry around a car while moving at 100kmph is a lot harder. Not only do you need to use a massive amount of key points but you need to produce a depth map in millisecond time frames.

Re: Lens Blur in the new Google Camera app

#149

Post by lnanek2 »

cfqycwz wrote: post #124
wooster wrote: post #37

Earlier quoted context omitted.

Yeah, it's complicated. On the one hand, you have dodging and burning, which were often used in actual darkrooms and are still used by respected photojournalists to increase the impact of their photos. [0] Then you have things like this: http://en.wikipedia.org/wiki/Adnan_Hajj_photographs_controve... Where clumsy and obvious use of the clone tool damaged the reputation of an entire news organization. The AP standards…

I'm curious to know why the AP don't allow red-eye removal--if the only manipulations allowed are those that help restore the clarity and accuracy to reality of the photographs, I'm not quite sure why red-eye removal wouldn't be permitted--most people's eyes, after all, are not red.

Sure they are red - in the brief instant the flash lights them up. You can see it with a spotlight too, try following someone around a dark stage with a spotlight.
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