Extreme imaging using cell phones: SeeInTheDark [pdf]
graphics.stanford.eduNice PDF. Some cool new stuff, smart decisions & remarks (noise, hotpixels, matching frames, etc).
If you have an iOS device, check out the app Average Cam Pro[1]. I've had it on my iPad for several years now. It does an awesome job taking noise-free, detailed pictures (as long as you don't hold it in your hand) by taking up to 100 pictures and merging them. You can adjust exposure etc. after the fact. Great stuff.
I have yet to find a good replacement for my Android phone. The closest thing to [1] is Multiple Exposure Camera [2] which has a terrible interface and no exposure setting, but some other nifty settings to remove moving objects etc. (note: just don't use the 0s interval or it crashes)
[1] https://itunes.apple.com/us/app/average-camera-pro/id4155778...
[2] https://play.google.com/store/apps/details?id=com.conslazy.m...
I just installed average camera pro. Very blurry. Not useful for indoor photography. Does not allow for adjustment of the shutter speed. Don't buy.
It's Nothing like what the paper describes.
Operator error. Like I said, it's not for handheld use (the only way to get blurry shots).
Correct way:
- Settings: Set the number of shots to 32 or higher. 1s interval. 3s pre-start timer
- Point at scene. Lean it against an object (don't touch/move) or mount on a tripod.
- Select exposure/focus/whitebalance with longpress (I select a light part of the scene, exposure/gain can be adjusted upward afterwards).
- Lock exposure/focus/whitebalance (could be an L in the middle, or text on your screen left, boldface is locked in)
- Shoot.
- After it's done (don't touch!) adjust the exposure if needed.
====
If you want even higher quality images, you can subtract banding noise (also mentioned in the PDF by the way).
In order to get the banding noise image for your camera:
- set shots to 128, delay 5 seconds
- point lens at light source (e.g. on table, don't move)
- hit shoot, put piece of white paper over the lens
- wait ~2mins (till it stops shooting).
- Select N in middle, "save image as noise fingerprint".
Then take another shot of a scene. Once final pic shows, hit N, now say "remove banding noise".
@ricw - here, a very quick and dirty comparison, iPad3, dirty keyboard, watch, focus/exposure locked on rim of the watch.
https://goo.gl/photos/9FM2c9JZRcDitPdd6
Watch full screen for best comparison. Taken in dark office, with just a desk light.
That was a great read, back in the early 80's at the Image Processing Lab at USC there was a project to turn, what was then, a new "CCD" imager into something that could collect images that were useful for image analysis. At the time these "TV" cameras were equivalent to a really low end web camera. What we came up with was basically the first half of this talk, taking frame after frame and integrating it into the frame buffer with a filter function. Sad that I can't find the technical reports in Google Books.
Very impressive! I have an app on my android that follows the same basic idea (accumulate frames) but doesn't come anywhere near this.
Unfortunately the author, in a reply to a youtube comment, stated that this is work he did for Google and doesn't know if the company has any plans for this.
He's Marc Levoy and he knows Google's plans very well; he just can't talk about them on YouTube, since it's the stuff that gets announced on stage at I/O and similar events.
There is an old free software package ALE ( https://unix4lyfe.org/ale/ ) that does some of the processing like this. It was much easier to get working if you had linear light images... and registration of really noisy images was quite hard on it.
Here's a (v short) video by the paper's author showing the app in action with there manuscript that features early on in the paper: https://youtu.be/S7lbnMd56Ys
In php is quite simple to merge images by pixel, I also tried to delete moving object https://github.com/br1n0/phpPhotosMerger
Nice job
Is this what makes the google pixel phone camera so outstanding? it would explain why a technically inferior camera (slower aperture, no optical image stabilisation) outperforms both apple and Samsung flagship phones.
Mirror [85 MB]: https://dl.dropboxusercontent.com/u/9910153/seeinthedark-pub...
Another mirror in case it goes over the dropbox limit: http://files.jjcm.org/seeinthedark-public-15sep16.key.pdf
Thanks, it did :)
I just want to say, I only came for the comments, but clicked after seeing people report so many downloads that it went over your rehosting limit.
The pictures in the PDF are absolutely stunning. I encourage everyone to have a look.
If anyone needs a quick spoiler (a pair of comparison images I copied from the PDF into a gallery for you) here you go:
Dropbox suspended my public folder due to large bandwidth to the mirror.
I think I can post this instead as it doesn't use my Public folder: https://www.dropbox.com/s/ixruqswy86fwr8t/seeinthedark-publi...
Hubble - does it take one long exposure or similarly multiple short ones?
A bit of both. Hubble can have single exposures that are hundreds of seconds long - but remember it's in low orbit, so eventually the subject will fall beneath the horizon. Most Hubble observations stitch together exposures from multiple orbits. Ultra Deep Field is an extreme example which comprises ~a million seconds of exposure over 400 orbits: https://en.m.wikipedia.org/wiki/Hubble_Ultra-Deep_Field
In astronomy you need multiple exposures to get rid of cosmic rays, which appear as bright lines or dots. A median filter can be applied to the exposures. HST uses tools called drizzlepac and multidrizzle to combine multiple dithered images to better make use of the telescope's native resolution which would otherwise be degraded by the detector.
>Need long exposure, but cell phones have no shutters.
Mine have... 1020 and 808.
excellent! now someone make an app out of this.
Sounds interesting, too bad the server is dead