Public Lab Research note

Tips on Sorting on Windows, including re-naming filenames

by eustatic | June 08, 2014 17:03 08 Jun 17:03 | #10540 | #10540

To Grind or to Automate?

During the Barataria work, mapknitters have found that sorting the images from flights to be a time limiting step. Many of us work in the windows environment, and use windows or (free) picasa preview to quickly scroll through thousands of images, but selection can still take hours.

There's a general guideline that a map shouldn't be made from more than 30 images, or you should consider how to map the area at a higher altitude. Experienced cartographers can handle more than that, but it seems that most people will probably only have patience for ten images or so. Alex Stoicof, as an experienced mapmaker, expressed a bit of frustration that she could georectify imagery in QGIS much faster than stitching in mapknitter, and would have mapknitters use that open source method.

There has been repeated discussion of using Visual SFM to stitch images, and thus let the computer decide which images are the most useful. This has not yet been actualized, as Chad Netto is the only one which experience using Visual SFM to do such a computationally intensive task.

Numbers, Names, and 'A,B,C's'

get rid of water, shoe shots, find the b's and c's

Initial screening of the ~2000 photos on an SD card can include notes on the ranges of numbers containing shots of the launch and the landing --photos that might be useful for "aeries" or "selfies" or expository imagery (C), but not for mapping.

Similarly, photos series often contain oblique shots that have no mapping value, but can be beautiful illustrations of the landscape nonetheless (B).

It generally saves time to skip to the highest altitude shots first, just like when mapknitting. This can give you a better mental representation of the features of the landscape as you make your photo selection. I find that I have to make a mental map of how the features fit together to make a decent photo selection. This takes more brainpower than you would think, especially for tricky wetland photography.

The number of the filename allows a mapper to locate a similar photo in the series, if that is ever needed again, so the file number is information worth keeping.

Naming the file makes it searchable by string.

In windows file explorer, images can be viewed as thumbnails (see photo), and the thumbnails can be viewed at different resolutions by selecting such in the "View" menu or using the scroll wheel to enlarge the images.

a little history

During initial meetings of mapknitters in 2013, Scott showed his method, which entailed re-naming the images to include descriptions.
--changing filenames from "IMG1234" to "IMG1234 west wetland berm unplanted"
with the idea being that images would then appear as distinct, even when only viewing the filenames, enabling an informal selection that was simple to drag and drop to google drive for collective stitching effort in mapknitter.

Jenna DeBoisblanc had the idea of re-naming the best mapping photos with alphabetical prefixes,

"IMG1234" to "a IMG1234."

This would promote good map photos to the top of the filenames in a detail view.

Scott had the idea, then, of "b" and "c" photos --"b" meaning useful obliques, and "c" meaning "aeries" or funny shots with other uses.

Thus, from ~2000 images, the sort will contain an alphabetical list of photos, sorting on their utility and retaining the image number, in case mappers want to return to the original imageset for a similar image geographically close to a previously selected image.

Thus, a collection of best images might end up like this:

a IMG1234 start map
a IMG1246
a IMG1276 pond feature
a IMG1345 boat alexis aerie
b IMG1187 cool oblique surge barrier feature
c IMG1445 alexis

For Infragram, numbers can be correllated by name, i.e.
a IMG1234 RGB IMG1344 IR

so that their matches can be easily found

From here, the numbered photos would be uploaded to google drive for collective use. Placing them in the top of the list makes it simpler to drag and drop photos.

next steps

We should be recording how much time it takes for trained and untrained, experienced and inexperienced mapknitters to sort images, so that any software authors can think about what processes are worthy of automation and which processes could be programmed with human instruction.

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Great tutorial! I added it to the balloon mapping wiki page

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This is a really important topic. Scott, what is the program in the main image above? Is that what you use to do the sorting you describe here? What version of Windows are you using?

Windows always comes with Windows Media Player which can display, sort, rate, and tag photos. Here is a tutorial for sorting, rating, and tagging photos in Windows Media Player 12. It might be more suitable than Windows Explorer. Windows Explorer also allows most of these functions, but Media Player is designed to maintain a database of media assets, so is probably faster and smarter at it. I assume Windows Explorer does not create a database, so every sort requires extracting data from each photo file.

Neither of these programs is very adept at the task of organizing photos, so it would be good to hear about other Windows programs that are. I don't know of any free programs, so I bought Adobe Lightroom. My Lightroom database has 78,000 photos in it, which includes all the EXIF data, IPTC data, other metadata, and exposure/cropping adjustments (the photo files are not in the database, just thumbnails and a pointer to wherever they are on my hard drives). The program still runs fast, unlike Windows Explorer which bogged down sorting a few dozen photos. Lightroom can store a rating (1-5) for each photo, but also a color code (1 of 5), and a flag (yes or no). So there is never a need to edit the file name of a photo, which as Scott says usually encodes the capture order of the photos and should be maintained. Lightroom allows infinitely resizeable preview icons, rotation, and sorting on 12 parameters. When photos are imported from an SD card or hard drive, the file name can be modified to include a meaningful string, and tags, titles, location, and dozens of other fields can be automatically entered for each photo. If all or some of your kite photos are too dark, or too light, or too dull, Lightroom can batch adjust them. It can even batch crop photos, so if 500 photos have the soda bottle edge in the corner, or a timestamp, you can crop it out of all of them at once.

Lightroom costs $150 or $80 for academics. Or subscribe to Photoshop for $10/month for the rest of your life and they throw in Lightroom. There is a 30 day free trial.

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Chris, interesting point about the tags and software.

I use picasa, as it lets me scroll through images faster than windows preview alone. I've used it on XP, 7, the other one, and windows 8.

What I do like about the naming system that we have stumbled into is that it's pretty platform-neutral, while containing three kinds of information.

It would be nice to have something that displays the photo on a map, or the lat / long, more easily, as windows doesn't always make that part of the EXIF data very obvious. Picasa does this mapping thing better. I use flickr a ton, and I like flickr for sharing and webhosting, although it only seems to be going downhill as yahoo tries to monetize everything.

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Oh right, Picasa. Picasa was once my primary photo organizer. Then Google started to link it up with Google+ so it became a front end to storing your photos online with Google. It got really confusing, and it seemed like the default action was uploading my photos to Google+ even if I didn't want them there. Picasa (Google+) and Flickr are great ways to store photos online, but kite mappers probably have too many photos to make that efficient or economical. I think Picasa is free and should be a good solution as long as you learn how to keep the photos only on your hard drive.

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Hmm. I only use Picasa for this "quick scrolling" preview purpose, and because it instantly gives me a map with the location if there is EXIF data. I use it for nothing else. I haven't had to link it to any Google Plus evil, so.

I actually sort photos using file names and file folders. i'm kind of old school. all my photos get archived on harddrives.

thanks for the tips

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