The words, explained.
Photo metadata hides behind a wall of four-letter acronyms. Here is the small set of terms that actually decide what ScrubPony keeps and what it drops, each in a sentence or two, with a fuller page behind it if you want the depth.
What is in a photo 6
EXIF
The block that holds GPS, timestamps and your device serial.
GPS in photos
Coordinates accurate to a few metres, written by default.
XMP
Adobe's XML metadata packet — and often GPS again.
IPTC
Captions, credits and location names, in an APP13 record.
Embedded thumbnail
A small copy of the picture, from before you cropped it.
Maker notes
Undocumented vendor blocks — a good place to hide a serial.
How a JPEG is built 6
APPn segment
The 16 slots where metadata lives — and why the number tells you nothing.
JFIF
The APP0 header almost every JPEG starts with — and its thumbnail-carrying cousin.
ICC profile
Colour information that is kept by default, because dropping it shifts colour.
MPF
A block that can hold a whole second photograph, under the ICC profile's marker.
SOS marker
Where the metadata stops and the picture starts.
EXIF orientation
Why most metadata strippers leave you a folder of sideways photos.
The ideas behind it 4
Get ScrubPony
Strips identifying metadata out of your photos — JPEG, PNG, WebP and HEIC — without touching a pixel. A C99 command line tool for macOS and Linux, and a native Android app on the same core.