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Google's New Camera App Simulates Shallow Depth of Field
New submitter katiewilliam (3621675) writes with a story at Hardware Zone about a new feature that Google's working on for Android phones' built-in cameras: the illusion of shallow depth of field in phone snapshots, which typically err on the side of too much in focus, rather than too little. Excerpting: "The Google Research Blog [note: here's a direct link] revealed that there's quite a fair bit of algorithms running to achieve this effect; to put it in a nutshell, computer vision algorithms create a 3D model of the world based on the shots you have taken, and estimate the depth to every point in the scene."
There is no 3D modelling involved. And the results are, well, mixed.
Why would I want to ruin large parts of a good image with this effect? It seems just as stupid as adding a large lense flare.
comes with a new 'Lens Blur' feature that lets you adds creamy bokeh to your pictures.
Yeah, hi, I have a question. Does it have to be creamy?
Brave Sir Robin ran away. ("No!") Bravely ran away away. ("I didn't!")
Just take a look at the auto-blurring used in street-view, nothing beats it. My neighbors dogs face was blurred instead of their kid. ;)
What this world is coming to - is for you and me to decide.
Lumin pretty much does this by the virtue of how it works. Nothing new to be seen here.
As is obligatory in any discussion of phone cameras, there is a fundamental difference between a device designed solely for photography, and one where photography is a relatively minor feature in a device designed mostly for mobility and communication. Advancements in this second field should be considered in an entirely different light (if you'll pardon the pun).
Another 'new feature' that's been out for over a year. https://itunes.apple.com/gb/app/focustwist/id597654594?mt=8 Kinda like the 'awesome' photosphere which MSFT had out for 2 years (as photosynth) before they did it.
When Google finally reveals its true name, Skynet, this is the technology that will allow its T-1000s to exterminate most of humanity.
But don't worry, they'll be sure to take an instagram of your death and post it to your Google+ livestream so your friends and family can mourn.
(There will also be ads for bereavement-related products. Neither Google nor Skynet are monopolies, honest.)
Futurist Traditionalism
But I absolutely, totally LOVE depth of field. Screw the art school graduates. I bought a large screen digital tv for the illusion of a window upon the world.
I would like to think -- I sincerely HOPE -- that artificially inducing audience "focus" by depth of field will be as quaint as silent movie captions in 50 years.
there's quite a fair bit of algorithms
I'll wait for version 2, with 50% more algorithms.
systemd is Roko's Basilisk.
Distortion lowers contrast? I thought internal reflections lowered contrast. Also, while all you've mentioned is true, I'd expect that lenses of moderate quality (and reasonable aperture) are probably possible, if expensive, in the thickness budget (which seems to be the limiting parameter in phones). But people certainly aren't ready to pay for such lenses in cheap phones.
Ezekiel 23:20
He seems to be mixing some terms a little bit. Correcting distortion lowers sharpness -- though for any image displayed only at 1080p, it probably makes no difference. Correcting some other aberrations, like chromatic aberration (CA) lowers contrast (and sharpness). Higher sensitivity in a digital sensor lowers contrast a whole lot more, though. That, and poorly-controlled lens flare, usually the major driver of low-contrast images out of smartphones. If you take a picture in daylight, don't point it right at the sun, and have a clean lens, the picture comes out pretty good.
I don't have a good sense as to how good the smartphone lenses are now. But people are now making pancake lenses for interchangeable-lens cameras that are tiny and of very high quality. I suspect that it's not to hard to engineer good smartphone lenses, either.
The problem is that with such a small sensor, you need very bright lenses to get shallow depth of field or good low-light performance, and those are just plain hard to make.
Wow. You're so awesome. You own a big-boy camera and know all the fancy photography words!*
That's what you wanted to hear, right? Because I can't think of any other good reason for you to post this.
The "muggles" have all got cameras now. This is just a nice bit of software that'll make their shots a bit more fancy.
Get over it.
(*disclaimer: so do I, but I don't use it as an excuse for scoffing at those who don't)
You'll take my Haruo Sato designed lenses away from me when you pry them from my cold, dead fingers.
No-one's coming for your lenses, you self-aggrandizing lunatic.
systemd is Roko's Basilisk.
I would like to think -- I sincerely HOPE -- that artificially inducing audience "focus" by depth of field will be as quaint as silent movie captions in 50 years.
The point of inducing focus is because not everything in the frame is as important as everything else.
Yes, if you're on top of the Grand Canyon, the Eiffel Tower, or the Great Wall of China, you may want to have the entire panorama in focus.
But if you're at (say) a street festival you may only want your friends in-focus, and not the fellow in the background who is mid-bite through a kebab. The important part of the picture for the grand parents is the smiling grandchild, not the playground's wing set in the background.
Can boken be overdone? Sure. A 1mm think depth of field is overdoing it, but so is shooting at f/16 everywhere. But even a thin DoF and the right can result in some magical results:
http://regex.info/blog/2012-05-28/2001#i110569bw
Wow. You're so awesome. You own a big-boy camera and know all the fancy photography words!*
This being slashdot, I think it's appropriate to discuss the technical aspects of photographic lenses. You might even learn something by reading it with an open mind.
The best feature of the new camera app is that if you try to take vertical video it puts up an overlay telling you to hold it right! Hopefully everyone will copy this!
It's a pain in the ass to use on the tablet "too fast.... too fast"
"If any question why we died, Tell them because our fathers lied."
Just what is needed . . . another Photoshop-esque filter for all the douchebag hipsters of the world to make their snaps look even more deep and brooding.
The summary makes it sound like this is an algorithm tuning problem - "err on the side of too much in focus" - which isn't the case. It's a byproduct of sensor size.
Even with real cameras the rule of thumb is a full frame (35mm film equivalent size) camera, at a given focal length, has a stop "better" depth of field than a camera with an APS-C sensor taking the same picture - so a Nikon D7100 would need to shoot at f/2.0 to get the same blurring as a D800 shooting the same photo at f/2.8.
Most camera phone sensors are rather tiny compared to real cameras.
On a side note... pedants may going to have fun nitpicking all of this apart. :-)
#DeleteChrome
and Teh G is gonna have to pay. AGAIN!
Digital TV with artificial interference.
Digital audio player that simulates permanent scratches in vinyl records.
Automobile interior that smells like horseshit.
Digital camera that 'exposes' (erases) your photos if you open the battery compartment incorrectly.
I have blurred out backgrounds of photos to bring attention to the foreground, but it never looks the same as when you actually use a large apeture on a SLR.
The reason cell phone camera err on the side of too much in focus is because they originally were all fixed-focus lenses. If you didn't have a high depth of field, you'd have to make sure your subject was an exact distance from the camera to get them in focus. Even once we had focusing lenses the auto-focus software wasn't the greatest at determining what the real subject of the photo was supposed to be.
You know what would give a great shallow depth of field? A better lens in the camera. A lens with an aperture that could open up to lower f-stops would give a REAL depth of field effect, plus it would make the camera just plain better at taking pictures -- better low-light performance, less noise in high ISO speeds captures.
You'll take my Haruo Sato designed lenses away from me when you pry them from my cold, dead fingers.
But it's not an Apple board, so there's no need to be so smug about it.
APK quotes people (including myself) without context and should not be trusted. Just thought you should know.
This being slashdot, I think it's appropriate to discuss the technical aspects of photographic lenses.
The AC wasn't trying to start a discussion. He just wanted to sneer down his nose at people using "inferior" tech.
We all know real cameras take better photos than smart phones, and this software isn't going to suddenly close the gap, so I don't know why the AC was acting so threatened and insulted.
systemd is Roko's Basilisk.
I think I know why google is doing this, it's to combat complaints about google glass taking unwanted/unwelcome images of people.
This is an attempt to help aleiveate people's fears about glass. If they can say that all the background of images taken with glass will be blurred beyond recognition that will go a long way with normal people that were worried about being filmed by glass
I am not a fan of glass in anyway shape or form! Blurred background or not !
BNZ is too lazy to login
*is* working on? It's already released.
I saw this a few days ago on my son's upgraded nexus phone. The neat thing is you can adjust the focus after taking the picture.
unless the sensor were much larger. even at fast focal ratios, a cell phone sensor still has close to infinite depth of field if you're focusing on any subject closer than a few inches away. The smaller the sensor size, the shallower the depth of field for a given focal ratio. That's why large and medium format lenses don't have to be as fast as 35mm.
The problem with "artistic" blur: shrink the image a bit, and the blur is gone!
(Try it and be amazed).
If Pandora's box is destined to be opened, *I* want to be the one to open it.
And my ex-wife simulated Shallow Depth of Character!
that would be really useful for extracting mattes and such in photoshop!
I tend to side with the pragmatic individuals here who are saying, it's bad enough that our modern historical record lacks the fine grain of Matthew Brady's silver emulsion plates and are generally USELESS for blow-ups of large groups of humans standing in groups --- "Mommy why does granny look like my LEGO people?"
In order to preserve what vibrant detail can be captured and push focus tricks into post-production where they belong, how about this,
A stereo multi-megapixel camera, where a second ccd+lens is on an outrigger that stores against the body but can be slid or swung out to human eye separation or better. It would click into position parallel with the main lens, but could also swivel outward and click precisely ~30,45 degrees out, so you could more easily build stitchable panoramas.
The operating modes:
1. Ultimate 3D HQ stereo photographs where the max resolution of both lenses is committed to memory, for panorama stitching or delaying 3D parallax calcs to post processing.
2. A series of more economical 2.5D modes from high to low resolution where a single photo is captured into memory --- but also --- a separate grey channel is saved, which is built by calculating parallax displacement of the pictures arriving from the lenses to the best of the camera's ability at max internal resolution, a smooth overlay that ranges from black=none=distant to nearby=white=close.
Your separate grey parallax channel saved in the 2.5 modes arrives into Photoshop ready to serve as a range selection mask so you can do these evil information-destroying transforms to your heart's content -- based on 'true' depth information.
<blink>down the rabbit hole</blink>
There is no 'all the information'. You are sampling both in space and time (shutter speed) integrating photons on a CCD. The process is noisy; all the information would be high frequency noise. Perceptually the high frequency components are distracting when it's not an element you're interested in. I suspect the spider and some web would be camouflaged in the background if the lens didn't act like a low pass filter on the background, doing a better job of allowing someone to see the subject.
As a fellow aspie (officially diagnosed, not "claimed"), we have just as much right to call people insensitive as anyone else - *if* we can actually figure out if that's what's going on around us. We don't have a monopoly on lacking the "filter" that stops us from saying what we're thinking !
In it's simplest form, it is that at the plane of focus, the lens will be as sharp as the lens is capable of being. In that plane, the circles of confusion will be as small as that lens can make them
Moving closer to or further away from the lens, the circles of confusion become larger and larger, until they can no longer carry any worthwhile information, and are completely unsharp.
The circles of confusion can be controlled to an extent, by altering the size of the lens aperture, referred to as "F-stop"
There is a fallacy among many people that a telephoto lens has a smaller depth of field. It does not. Any image made with any lens, at the same main subject size - and the same lens aperture will have the same depth of field. Most people get the depth compression or expansion of the various lenses confused with depth of field.
The circles of confusion effect can be in principle nullified by very small apertures. This is the "pinhole" lens. At some point, a pinhole aperture negates the need for any glass lens at all. There are many pinhole video cameras, and most of the smartphone camera lenses approach pinhole aperture.
The problem with pinhole lenses, is that they are hampered by diffraction. The hole is so small - near in size to the wavelength of the light trying to get through it, that light cannot be brought into sharp focus because it is being bent out of focus.
Now in practical terms, in the early days of photography, film sensitivity was much lower than it was when film hit it's peak of quality and performance.
Since this could make for uncomfortably long exposures, the solution was to use larger aperture lenses. Which had that shallower depth of field due to that aperture.
Not surprisingly, this fault was found to be an advantage in many cases. It allowed the camera user to focus on what they wanted to viewer to see. Portraits tended to look much better, as someone here noted, having th eeyes in sharp focus, while the tip of the nose was leaving forward focus, and the background out of focus is a very positive effect.
Another nice effect is the ability to remove obstructions. Properly used, a photographer can shoot through obstructions like chain link fences using depth of field. The fence disappears, at the cost of some contrast in the final image.
So while some folks like to call laws of physics, "Hipsterism", they are simply laws of physics. They are in fact arguing for what they are arguing against. Because modern Smartphone cameras are up against their own laws of physics.
Smartphone cameras use very small, very sensitive pixel packed sensors. This requires very small, very short focal length lenses.
In order to end up with images that look normal in aspect to the human eye, you need to gather information to be included at certain angles away from the center of the image. Approximating the human eye, so to speak.
As the imaging area gets smaller, what constitutes a telephoto lens, normal or wide angle lens gets smaller. In 35 mm film with it's 24 by 36 aspect, a focal length of 50 mm is fairly close in approximating this. Sensors for many digital cameras are a bit smaller, which is why many lenses for digital SLR's are shorter focal length. They do however, have about that same imaging capability.
So this should be a good thing really. Lenses get smaller, lighter. It sort of is, sort of isn't.
Let's look at that smartphone camera. Very small lens, with an even smaller aperture. Due to the small size of the sensor, it must be a very short focal length lens. And to avoid focusing, it has what looks a loto like a pinhole in there. It is a very short focal length semi pinhole lens. Not as much diffraction as a true pinhole, which is good. Very small aperture, which is not so good for image control, and a very short focal length lens, with all the defects those short lenses inherently have.
The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.