What the WhatsApp Cleaner scans and deletes in DeDup 1.5.3 on Android
The WhatsApp Cleaner in DeDup 1.5.3 looks at the images, videos and documents WhatsApp has saved on your phone. It finds exact copies, files you sent, and large files, and lets you delete them. It starts only when you tap Start Scan.
What it scans
It reads three groups of WhatsApp folders: WhatsApp Images, WhatsApp Video and WhatsApp Documents, inside WhatsApp's Media folder. Files in a Sent subfolder are kept apart from the ones you received.
- Images are read from Android's image index, videos from the video index, and documents from the general files index. The scan asks Android's media database (MediaStore) for files whose path matches; it doesn't walk the folders itself.
- Statuses aren't scanned. The screen's intro text mentions stale statuses, but the scanner leaves them out. A comment in the code says the hidden statuses folder isn't indexed and can't be reached without the all-files permission.
- Audio files aren't queried at all.
The screen doesn't ask for a permission of its own. What it can see depends on the media access DeDup already has.
How results are grouped
DeDup computes a SHA-256 checksum for files that share a size with another file, and for any file of 10 MB or more. Two files with the same checksum are byte-for-byte identical. Photos that only look alike aren't matched.
The results screen shows a Potential Savings figure, then up to three sections:
- Redundant Sent Media. Every file found in the Sent folders: images, videos and documents. The code adds all of them to this list. It doesn't first check that you still have a received copy. There's a Delete All button here, so look through the list before you use it.
- Duplicate Groups. For each set of identical images or videos, every file except the first is listed. The first one is left out of the list.
- Large Files. Files of 10 MB or more, largest first. The screen shows the top 10.
Potential Savings adds up the extra copies in duplicate groups and every file in Redundant Sent Media. It doesn't include Large Files.
Some matching is worked out but not shown in 1.5.3. Duplicate documents and sent-versus-received matches are computed, yet this screen has no section for them.
How deletion works
- Tap the trash icon on a row, or Delete All under Redundant Sent Media.
- If you're browsing as a guest, DeDup shows a "Sign in required" dialog instead, and nothing is deleted.
- Otherwise DeDup calls Android's ContentResolver delete on each file straight away.
This screen's code shows no confirmation step. It also doesn't build the system delete request that the photo and video scanners use, so DeDup doesn't raise that system prompt here. It doesn't send anything to DeDup's Trash either. In 1.5.3 nothing in the scanners does. The delete is permanent.
Only files Android reports as removed leave the list. If Android refuses a file, it stays in the list, and the screen shows no message about it.
What it can't see
- Any folder outside those three patterns.
- Files Android's media index doesn't list.
- Copies of a photo that exist outside WhatsApp's folders. It compares files only within what it scanned.
- Pictures that look similar but aren't identical.
Scope of this post
Checked against: DeDup 1.5.3 source code (Android).
Not tested on a device: what Android does when DeDup calls delete on WhatsApp's files, on any Android version. Also not tested: which documents the media index returns on your Android version, and how long a scan takes on a large library.