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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."
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.
Because often, what you can't see is as important as what you can. Imagination is important. Composition is important, and emotion is important.
Because it makes the intended subject stand out more.
systemd is Roko's Basilisk.
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.
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.
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.
lenses that can achieve a narrower field of focus are the more expensive ones, so there is established artistic value. Lens flare can also have value, and is really difficult to use effectively, so there is probably also a market for that.
Depends what you mean by 3D modelling. Looking further at the article, it's a depth mapping technique for each pixel. Which is more analogous to DOOM than Quake. Remember those restrictions? No bridges in the map, no tables. Just a single height for the floor and a single height for the ceiling at any map position.
As the OP says it's 2.5D not 3D.
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!
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
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
Just because you know what you're talking about, and we're among friends:
It's bokeh, with an 'h'. And it refers to the character of the blur, not the blur itself. If you've got an image, say f/3.4, a hipster might say "nice bokeh" to you, but he means that you have a good lens, not that you've selected a good aperture. And then he might also suggest you make a "glisse" print. ;)
And, of course, shallow depth of field is a huge fad, and there's an entire generation of kids who won't ever be able to tell where they were in any of their childhood pictures. *That* will seem very "early 21st century" in a couple decades.
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
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.
Consider this picture of a spider dining on its prey--possibly a cricket.
What's important? the spider, the web, the meal.
What's not important? the storm drain, the foliage
It's not completely successful, but both the foliage and the storm drain are out of focus, while the spider, the meal, and the web are in focus. The aperture control on a large sensor camera lets the photographer select where the blurriness ends, and where it begins. Generally, the longer the focal length of the lens, the more dramatic the effects of opening up the aperture. Since camera phones use short focal length lenses, the blurring effect is quite subtle, and is often insufficient to draw in the viewers eye.
In this particular case, it's a macro shot, so even a very narrow aperture (f/16) involves some blurriness. Quite often, macro-photographers use very narrow apertures-- f/16-f32, in an attempt to resolve all of the interesting aspects of their subjects.
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.
and emotion is important.
but I have aspergers you insenitive clod!
Who logs in to gdm? Not I, said the duck.
Bullshit.
A well done wide-open portrait with tack-sharp eyes and everything else blurred connects you with the model like no other shot could. I know it sounds hipsterish, but it's an immutable reality.
Right, the thing is though theres more going on to depth of field than just "This part of the image in focus, and that part out of focus". I mean its definately a useful effect because it pretty much defines what part of the photo your supposed to be looking at, but good shallow DOF really is quite an amazing effect down well and terrible when done bad.
On my 50mm lens (I recomend a 50mm to ANYONE whos playing with SLRs. Its a cheap lens, handles great in low light and very easy to take attractive photos with) the depth of field also interacts with light so you see these great specks of light all through the background and other esoteric effects that really enhance the effect. If I just put the background out of focus with a blur, it'd be just.... well blury.
Finally its not a linear blur either. Some parts are more in focus than others and this adds to the effect because its how your eye does it too.
The test photo in the article just makes it look like someones put a lasso tool on the model, inverted it, then just done some sort of blur on the background. Its just not the same as the DOF on a real wide apearature camera.
Excuse the Unicode crap in my posts. That's an apostrophe, and slashdot is busted.
Why would I want to ruin large parts of a good image with this effect?
Portrait photography.
Or any time when the presence of crap in the background degrades the photo. That candid picture of your Mom sharing a moment with your aunt would look great if it were not for the Ronald McDonald billboard in the background.
Will
Quality bridge cameras ($300+ models) also have the ability to mimic a narrow depth of field. That can be very useful in wedding party photography, etc, where capturing candid portrait shots is critical to the photographer's success, and he will not have time to swap between lenses on his DSLR.
On my Fuji HS25EXR, the camera identifies the subject with its face recognition technology and takes 2 or 3 shots, The foreground is handled normally but the extra images are used to double or triple expose the background for the shallow DOF effect. Results are often quite good and can reduce the amount of post work by quite a bit.
Will
You're describing Bokeh. And yes, it is one of those techniques that done well, can greatly enhance a picture. There are entire web sites and discussion groups devoted to the topic - which lens, camera, technique is best and who is a total poser. There have been numerous attempts to do this in software, all of which have yielded meh results. I suspect that Google's attempt will be another one of these, but who knows. Perhaps they will finally figure out how to let photographers match their $15,000 DLSR rigs with an $800 smartphone and a .99 app.
Faster! Faster! Faster would be better!
And, of course, shallow depth of field is a huge fad, and there's an entire generation of kids who won't ever be able to tell where they were in any of their childhood pictures.
Wow lets step back a bit. Though I guess someone called the automobile a fad at some point.
The battle for wider apertures dated back to post war. The 1950s was all about big lenses, wide apertures. I fondly recall using a Canon R mount 50mm f/1.2. Not a very sharp lens but provided incredibly narrow depth of field. Mind you it wasn't until the FE mount in the 80s they managed to get a 50mm f/0.95, something which Leica managed quite a lot earlier on their M series cameras in the 1960s.
Now that the history lesson is over, how about an art lesson. Depth of field is used to direct attention. If you want someone looking at a subject rather than the image on the whole you can isolate the subject by blurring the background. I did this on my holidays and I'm going to look back and think about what I looked like at the time who the hell cares where I was. If I wanted to take a photo of where I was I would do so. Now on the flip side, why the hell would you want to ruin a perfectly good photo of the Pantheon or some other wonderful place by standing in front of it? Why would you want to give up artistic control to some passer by telling them to look through the viewfinder and push the button.
You seem to know the technical details of how something is done, but not have a clue of why someone would do it. Go to your grandpa and ask him if he used wide apertures when he took photos. You'll likely find him don his oversize framed glasses and say "Kid, I was the master of bokeh before it was cool."
Fad indeed.