Steganalysis
Definition
The forensic discipline of detecting the presence of hidden data in a carrier file. Steganalysis uses statistical tests (chi-squared, RS analysis, sample pair analysis) and machine-learning classifiers trained on clean and stego media.
Related terms
- Blind Steganalysis
- Detection without prior knowledge of the embedding algorithm. A classifier trained on images with and without payloads generalises across multiple tools.
- Cover Medium
- The original, unmodified carrier file (image, audio, video, or document) into which secret data will be embedded. The cover medium is chosen...
- DCT Coefficient Embedding
- A steganographic technique that hides data in the quantised discrete cosine transform coefficients of a JPEG image after compression. Because the embedding...
- Embedding Rate
- The payload size divided by the carrier capacity, usually expressed as bits per pixel. Detection difficulty decreases sharply at low embedding rates...
- False Positive Rate (FPR)
- The proportion of true non-matches (or true negatives) that a classification method declares as matches (or positives). Also called the type I...
- LSB Substitution
- Least-significant-bit substitution: the lowest-order bit of each sample value (pixel colour channel or audio sample) is overwritten with one bit of the...
- Rich Model Steganalysis (SRM)
- A feature-extraction approach that computes hundreds of statistical features from pixel-residual co-occurrence matrices and feeds them to an ensemble classifier such as...
- Spread-Spectrum Embedding
- A technique that distributes the energy of the hidden message across many frequency components at very low amplitude, similar to a wideband...
- Stego Object
- The modified carrier file containing the embedded secret data. A stego object should be visually or audibly indistinguishable from the cover medium,...
- Targeted Steganalysis
- Detection methods designed against a specific steganography tool or algorithm. Effective when the tool is known but fails against novel or unknown...
Explained in these topics
- Steganalysis: Statistical Detection MethodsThe detection of steganographic content in carrier files, using statistical, machine-learning, or tool-signature methods to determine whether a file has been m...
- Steganography Principles and Common Carrier FormatsThe forensic discipline of detecting the presence of hidden data in a carrier file. Steganalysis uses statistical tests (chi-squared, RS analysis, sample pair...