JPEG Ghost Analysis
Definition
A technique (Farid, 2009) that identifies double-compressed patches by resaving a composite JPEG at multiple quality levels and identifying the quality at which the difference between the composite and the resaved version is minimised for a localised region.
Related terms
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- Copy-Move Detection
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- Cross-Reference Table (Xref)
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- Error Level Analysis (ELA)
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- EXIF (Exchangeable Image File Format)
- A metadata standard embedded in JPEG and TIFF files by capture devices. EXIF fields record camera make and model, lens data, exposure...
- Incremental Update
- The PDF mechanism by which an editing application appends new or modified objects to the end of an existing file without overwriting...
- PRNU Fingerprint
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- XMP Metadata
- Extensible Metadata Platform (ISO 16684), an XML-based metadata stream embedded in many PDF and image files alongside the information dictionary. Discrepancies between...
Explained in
- PDF Metadata Forensics and Document Image AuthenticationA technique (Farid, 2009) that identifies double-compressed patches by resaving a composite JPEG at multiple quality levels and identifying the quality at whic...