Security · Browser-first processing
Encode mode writes a length-prefixed message into a newly generated PNG; decode mode checks for the ImgNimble marker.
Select a supported file or enter the requested values, then run the tool.
This browser tool does not upload the selected source to ImgNimble. Closing or refreshing clears the selected files and generated result from the page.
Common questions
Steganography Encoder and Decoder reads the selected input into browser memory and performs its documented operation on this device. It does not submit the source file to ImgNimble while using this browser-first workspace.
A PNG carrying a hidden message or extracted text from a compatible PNG.
Steganography is not encryption. Recompression, resizing or social-media processing will usually destroy the message, and a determined analyst may detect it.
Steganography Encoder and Decoder validates the selected file before processing. Use JPG, JPEG, PNG, WEBP, GIF, HEIC, HEIF, SVG within the 40 MB per-file limit. Keep an untouched original for comparison.
The Steganography Encoder and Decoder workflow runs in browser memory. ImgNimble does not receive the source file for this local operation; refreshing or closing the page clears the selected input and generated in-page result.
Practical checks
Encode mode writes a length-prefixed message into a newly generated PNG; decode mode checks for the ImgNimble marker.
Keep the source, download the Steganography Encoder and Decoder result as a new file, and verify dimensions, transparency, colour, metadata and visual detail before replacing any production asset.