The upcoming move to iCloud Photos with iOS 8 and OS X Yosemite has got me worried. It’s not because I don’t trust Apple’s ability to pull off cloud services, but because my photo library hides a shameful secret: thousands of duplicate photos. My move from iPhoto to Aperture back in 2011, the MobileMe to iCloud Transition, and some computer backup/restores has created a mess of duplicate photos. With the cheap availability of massive hard drives, I put off doing anything about the problem because it was easier to upgrade to a 1TB drive than it was to go through and delete all those unneeded photos.
The time has come for some spring cleaning; with limited storage space in iCloud and my recent purchase of a MacBook Air, the problem of duplicate photos has ratcheted up several clicks in urgency. But what to do? Never fear, because PhotoSweeper can handle duplicate photo identification and deletion without putting you through the pain of manual review. Problem solved!
PhotoSweeper’s simple. You can point it at an iPhoto Library, an Aperture Library, Adobe Lightroom, or a folder of photos on your hard drive, then choose how you want PhotoSweeper to identify the duplicates. There are multiple options for this, and once you’ve done this identification, the app nondestructively isolates those photos by moving them to the trash or tagging them so you can easily delete them from within your preferred photo management app. PhotoSweeper’s intelligent enough to identify duplicates even if they’re not in the same format; a large number of my duplicate files are export-ready JPEGs I created from RAW files for a specific purpose like web sharing or printing. I rarely remembered to go back and delete these files, and my Aperture Library’s size reflects it.
PhotoSweeper’s main app window presents a photo browser and uses a simple workflow that lets you select photos, identify duplicates, then do comparisons to help weed out the unwanted photos. You can do a one-duplicate side-by-side comparison or see an overall view of all your duplicates grouped together, and the app can automatically mark photos it thinks should be deleted (it usually prefers to save the largest file, meaning the highest quality version gets saved).
PhotoSweeper makes a slight deviation from the normal File->Open, and instead uses either a Media Browser (accessed via a button on the lower left) or Photos->Add Photos to List. The Media Browser lets you point to an app-controlled photo library like iPhoto or Aperture, while the Add Photos lets you grab a folder using the standard file structure on your hard drive. The App imports all the selected photos, then you move over to the right hand side of the window where you can choose the Comparison Method; essentially, you tell the app how you want it to identify duplicates. There are six choices:
- Bitmap: PhotoSweeper makes a small version of the image to compare, and flags those that are visually the same
- Histogram: The app identifies duplicate images by their RGB histograms
- Time Interval: The app will flag images that were shot close together—great for manually identifying photos shot in burst mode (something iOS 7 automated)
- Time + Bitmap / Time + Histogram: The app can identify photos that are similar but not exactly the same by identifying photos that look the same and were shot at the same time
- Duplicates Only: This mode identifies only photos that are exact copies, and is the most conservative. The other modes identify near-matches and come with a slider letting you choose the exactness of the Matching Level, which can help you weed out photos that are similar (e.g. multiple shots of the same scene).
Once you’ve loaded photos and selected your comparison method, PhotoSweeper launches a window that feels very Hollywood-esque; it flashes tiny versions of the pictures being compared, much like facial recognition in the movies. But the app is actually comparing photos and identifying duplicates, then it slides you to the right to the Results pane, where it groups and presents photos identified as potential duplicates. The app can either automark duplicates or you can go through and manually mark duplicates. I found the auto mark selections to be accurate almost 100% of the time.
At the right of the window is a photo information pane that shows a preview, histogram, and the full EXIF data on the picture, so if you choose to review the duplicates you can easily get lots of information to support your comparison. At the bottom of the window the full file path of the selected photo is shown, which is great for figuring out where a particular picture exists. You have all the data you need at hand when conducting a review.
Once you’ve marked your duplicate photos, you can Trash the items elected quite easily with the “Trash Marked” button. My favorite PhotoSweeper feature is its nondestructive nature, so the photos you mark as trashed are not permanently deleted. Instead they’re moved to the iPhoto/Aperture Trash, OS X Trash, or moved into a special gallery in Lightroom where you can review or restore them if needed. This gave me the opportunity to review the photos that were left after PhotoSweeper did its work, so I could make sure I still had the shots I care about.
Photos and videos are becoming massive space hogs on our devices, as evidenced by iOS 8′s disappearing photo/video feature in iMessages. Apple has recognized how much space they take up, so photos and videos are now ephemeral; if it’s important you must save it, otherwise it disappears. However, for those of us who bought into the Mac-as-a-digital-hub, there are 14 years worth of non-ephemeral pictures that have been slowly multiplying in iPhoto and Aperture libraries. Duplicates are inevitable as we did backups, migrated computers, made edits, or switched apps, and PhotoSweeper’s powerful and refined features make it easy to declutter the digital detritus that’s resulted over the years..
The only missing feature I’d like to see in PhotoSweeper is an ability for it to reconcile photo duplicates across other apps, such as iMessages and Mail. I know I’ve got pictures that were sent to me via iMessage and which I subsequently saved into Aperture; iMessage isn’t a photo management tool, so I’d obviously like to be rid of those copies. Otherwise, it’s a stable and solid app that does exactly what it advertises—it’s an app that does one thing but it does it very well, and it’s helped me streamline my Aperture library in preparation for iOS 8/OS X Yosemite and the iCloud photo transition.
The full featured version of PhotoSweeper comes with all the duplicate identification modes and is well worth its $10 price tag, being especially useful to amateur or professional photogs who take multiple shots of a scene to capture just the right picture. If you just need to quickly streamline a collection of snapshots, there’s a $3 Lite version which only identifies exact duplicate photos and removes them. The Lite version would be great if you need to weed out your library of mainly snapshots that might have occasional duplicates from editing. There’s also a free demo version available outside the App Store that lets you try the deduplication on up to 101 photos.