DCT coefficient embedding
Definition
A steganographic technique that hides data in the quantised discrete cosine transform coefficients of a JPEG image after compression. Because the embedding operates on the compressed data rather than the pixel values, the hidden data survives JPEG re-saving.
Related terms
- Cover medium
- The original, unmodified carrier file (image, audio, video, or document) into which secret data will be embedded. The cover medium is chosen...
- 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...
- 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...
- Steganalysis
- The forensic discipline of detecting the presence of hidden data in a carrier file. Steganalysis uses statistical tests (chi-squared, RS analysis, sample...
- Stego object
- The modified carrier file containing the embedded secret data. A stego object should be visually or audibly indistinguishable from the cover medium,...
Explained in
- Steganography Principles and Common Carrier FormatsA steganographic technique that hides data in the quantised discrete cosine transform coefficients of a JPEG image after compression. Because the embedding ope...