# Invisible Watermarks - Steganography ### **What are invisible watermarks?** If you came this far in reading the documentation, you've probably already tried scanning one of our watermarks. Invisible watermarks are a form of steganography using fourier transform, but put on steroids through deep learning enhanced algorithms for detection, error correction and normalization. Xeal uses invisible watermarking technology to link digital and physical assets to the blockchain, ensuring authenticity and enabling verification. Although detectable by machines, the watermarks use a chrominance channels that are barely visible through human eyes. ### **Key Features** 1. Imperceptibility: Watermarks are embedded in a way that is undetectable to the human eye. 2. Robustness: Watermarks can withstand common image processing operations like compression, resizing, and color adjustment. 3. Verifiability: Watermarks can be detected and verified using the Xeal mobile app. ### **Embedding Process** 1. Color Space Conversion: Image is converted from RGB to YUV or YCbCr color space. 2. Watermark Generation: A pseudo-random sequence of bits is generated to represent the watermark. 3. Embedding: The watermark is primarily embedded in the chrominance channels (U and V) to minimize visual impact. ### **Detection Process** 1. Image Preprocessing: Captured images are corrected for distortions and normalized. 2. Synchronization Signal Detection: A known pattern is identified to align the image for watermark extraction. 3. Watermark Extraction: The embedded watermark is retrieved using inverse operations of the embedding process. ### **Applications** * Linking digital assets to blockchain records * Authenticating physical products * Enabling augmented reality experiences * Protecting intellectual property ### **Security** Watermark hashes, rather than actual watermarks, are batched together as proofs and stored on the blockchain to enhance security and prevent unauthorized replication. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://xeal.gitbook.io/xeal/getting-started/invisible-watermarks-steganography.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.