Copy-Move Detection
Definition
A class of image forensics algorithms that search for duplicated regions within a single image, indicating a patch-and-conceal manipulation. Implemented via block feature matching or keypoint descriptor matching followed by geometric consistency filtering.
- Target
- Duplicated regions within a single image
- Methods
- Block or keypoint descriptor matching
- Follow-up step
- Geometric consistency filtering
Common questions
How does copy-move detection differ from splicing detection?+
Copy-move detection looks for a region duplicated from elsewhere within the same image, while splicing detection looks for content inserted from an entirely separate source image.
Why is geometric consistency filtering needed after the initial feature matching step?+
Raw feature matching often produces false matches from naturally repetitive textures like grass or brickwork, so requiring matched regions to share a consistent transformation removes those false positives before flagging a manipulation.
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