Best shot selector mode (Poor man's IS)

[Lilien]

Poor man's Image Stabilizer - best shot selector mode

What about shooting (fast continuous) a (predefined?) number of shots,
compare the JPEG file sizes, and then only keep the sharpest shot
(biggest file size will contain more details)?
The auto deletion should include the RAW files, so there only remains
the best/sharpest JPEG/RAW pair.

I would like to see this feature, is it possible?

I think this functionality is not possible as a script, because there are
no script file commands, right?

[jetzt]

In Theory a really good idea, how I think, but what, if the best shot is the one with the lower depth of field?
You loose your best shot
But marking them could be indeed useful.

[PS]

Bad idea to let the camera decide which picture is 'best'…

[yg2007]

I'm so glad that someone are requesting the same feature.  I think BBS is still useful nowaday. I really wish such feature could be added. I hope it will be a script so that I could trigger BBS with just one click.

here's some info about BBS:
http://digitalimaging.patyuen.com/shootout/cp5kvg2/bss.htm

[carlos]

I think BBS is still useful nowaday. I really wish such feature could be added.

Currently cataloging hundreds of small to tiny items using an old Nikon 775 (2.14 mp) because it has the BSS feature (shooting hand-held macros). Of course, one may shoot bursts with another camera; selecting the biggest file oneself ... but better when this is automated!

A great addition to CHDK, imo, if possible.

Thanks for the suggestion Lilien!

[carlos]

............  if the best shot is the one with the lower depth of field?
You loose your best shot

Exposure settings remain constant; therefore no change in depth of field. Selection is from a "burst" series - BSS keeps the sharpest shot.

Bad idea to let the camera decide which picture is 'best'…

"Best" here means sharpest; BSS applies to focus only. This is a useful program to use with discretion.

[brainwash]

Ok, I have compiled a list of articles that deal with digital still image stabilization and focus detection (which is what I think the BSS is doing):

Image motion deblurring (short) - http://homepages.inf.ed.ac.uk/rbf/CVonline/LOCAL_COPIES/AV0506/s0198594.pdf

Method for reducing motion blur in a digital image (patent, somewhat abstract) - Method for reducing motion blur in a ... - Google Patents

see pages 102 and 103 of this document: http://www.safecomprogram.gov/NR/rdonlyres/B20DC842-B760-4DB0-B3B6-D3F1B0A5F26B/0/PS_SoR2_v10_9112006.pdf
for measuring sharpness in an image

sharpness determination using gaussian blur (very slow, for reference only) - http://www.ph.tn.tudelft.nl/~lucas/publications/2003/CAIP2003_JDMGRALVPV.pdf

google's (no)answer - Google Answers: Autofocus program or algorithm - the suggestion to use image size is very useful and could mean BSS could be implemented really fast with acceptable results; it could really mean shoot in burst mode and record which files are written, then delete all but the largest written since the shutter has been pressed

last, and probably least, a method for improving auto-focus speed and accuracy, would be nice if implemented on these cheap cameras, but I wouldn't hold my breath - Welcome to IEEE Xplore 2.0: Efficient auto-focus algorithm utilizing discrete difference equation prediction model for digital still cameras (don't ask me for the paper, I do not have access to the site since I graduated)

[carlos]

....... BSS could be implemented really fast with acceptable results; it could really mean shoot in burst mode and record which files are written, then delete all but the largest written since the shutter has been pressed

brainwash,

That's just, as I understand it, what Nikon BSS does. I take 4 or 5 shot bursts x 3 in BSS, then select one of the three 'bests' by file size (saves comparing images by eye).

Thanks for bumping this topic.

carlos (the needy)

[LjL]

Feature implemented.

I'm attaching a patch to trunk / AllBest 441, which adds a core/bss.c and modifies core/main.c (and other files for configuration / locales).

I'm also attaching a binary build for my camera, the A720IS.

The system can be activated in the "Extra photo operations" menu, and will engage when the camera is in Continuous drive mode.

The JPG file that takes the most space is kept, others are removed.

KNOWN BUGS:

• deleted files will still be indexed in Play mode until the camera is turned off and on again, and show up as "Unidentified" (it's a feature so you can see which one was kept, not a bug!)
• the system will deactivate as soon as a shot is taken in anything but Continuous mode FIXED
• I can't get the darn menu item text to actually show up, you'll see only a blank menu line with a togglebox FIXED
• camera sometimes crashes after the first 3 shots or so FIXED
• BSS bails out and deactivates if you release shoot-full but keep shoot-half pressed while taking burst shots

Clearly, this patch DELETES FILES, so while testing is appreciated, please be careful, use at your own risk, and preferably on an SD card with no important data.

[PhyrePhoX]

nic work
i think you built a lot of diffs by now, they seem to be scattered around this place. don't you wanna create a thread gathering all these changes and explaining them a little bit in detail?

[carlos]

THANK YOU, LjL!

[LjL]

PhyrePhoX, you mean, like... a build? ;-)
(Can't really be a build, especially the DataGhost-related parts... I hope the collaborative build guys or even trunk might be interested in merging some)

Anyway, I suppose "General Discussion and Assistance" would be the place for that?

[PhyrePhoX]

well, i didnt really mean a build. yeah, of course we're interested in merging with the collabo build, who wouldn't
general discussion and assistance sounds about right.

[LjL]

I uploaded a new revision. It fixes two bugs and a previously unknown memory leak, and the code should be cleaner (as in, commented).

It also tries to avoid camera crashes, but unfortunately they still seem to occur. I guess they might be related to the fact that I'm deleting files under the OS's nose, I'm not sure really.

[LjL]

This time I might have fixed the nasty crashing bug - or not.

Please test this, as the crashing occurs unpredictably - if it still occurs -, and I need to know if it does occur.

One problem that's certainly still there is that, if you release shoot-full but still keep it half pressed, and then resume taking photographs, BSS bails out. It's actually not a problem, it's the "safety" routine that thinks there's something wrong and disables BSS just in case.

But the question is, should this behavior trigger anything special? I was thinking, for instance, that half-releasing the shutter button could mean "I've changed my mind, please keep all the shots I've taken". What's your preference?