Effective detection for linear up-sampling by factor of fraction.
Summary
This study introduces a new method to detect linear image up-sampling. The technique accurately identifies up-sampling and its fractional factor, outperforming existing approaches.
Area of Science:
- Digital Image Processing
- Computer Vision
Background:
- Linear up-sampling is a common image processing technique.
- Detecting the specific resampling factor used is challenging for existing methods.
Purpose of the Study:
- To develop an effective method for detecting linear image up-sampling.
- To identify the resampling fraction used in image up-sampling.
Main Methods:
- Resampling Matrix Construction (RMC): Derives the resampling matrix for fractional factors.
- Zeroing Mask Derivation (ZMD): Creates a zeroing mask for the resampling process.
- Up-sampling Detection (UD): Detects up-sampling using derived zeroing masks.
Main Results:
- The proposed method effectively detects linear up-sampling across various fractional factors.
- The method can accurately recover the specific up-sampling fraction.
- Preliminary experiments confirm the effectiveness of the proposed approach.
Conclusions:
- The developed method offers a robust solution for detecting linear image up-sampling.
- This technique provides a means to identify the resampling fraction, improving image forensics and analysis.
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