Noise Residual
Definition
The signal remaining after a denoising filter removes the scene component from an image. For PRNU estimation, the residual approximates the sum of PRNU and random noise. Averaging many residuals cancels random noise and isolates PRNU.
Related terms
- Camera Noise Model
- A mathematical description of a sensor's noise as a function of signal level, combining signal-dependent shot noise and signal-independent readout noise. The...
- CFA (Colour Filter Array)
- The mosaic of colour filters placed over a sensor so that each photosite captures one colour channel. The Bayer pattern (RGGB arrangement)...
- CFA Phase
- The spatial offset of the CFA mosaic pattern in an image. Pasting a region from a different image or after a non-CFA-aligned...
- Demosaicing
- The algorithm used to interpolate full-colour pixel values from the single-channel raw sensor data. Common methods include bilinear interpolation, gradient-based algorithms (AHD,...
- Flat-Field Image
- A photograph of a uniformly illuminated surface, typically a white wall or diffuser, taken at moderate brightness to avoid saturation. Used to...
- Normalised Cross-Correlation (NCC)
- A scalar statistic in the range -1 to 1 that measures how closely the noise residual of a query image matches a...
- Peak-to-Correlation Energy (PCE)
- An extension of NCC that computes the ratio of the squared correlation peak to the energy of the surrounding correlation map. PCE...
- Photo Response Non-Uniformity (PRNU)
- A fixed-pattern noise component caused by microscopic sensitivity differences between individual sensor pixels. PRNU is deterministic and camera-specific, making it a sensor...
- PRNU Fingerprint
- Photo Response Non-Uniformity: the unique pattern of pixel-level sensitivity variations in a camera sensor, which acts as a device fingerprint. Used to...
- Steganography
- Concealing one file inside another in a way that hides the existence of the hidden file. LSB image manipulation, JPEG DCT coefficient...
Explained in these topics
- Noise and CFA Inconsistency DetectionThe high-frequency component of an image obtained by subtracting a denoised version from the original. The residual retains camera-model fingerprint noise and...
- Photo Response Non-Uniformity and Sensor FingerprintingThe signal remaining after a denoising filter removes the scene component from an image. For PRNU estimation, the residual approximates the sum of PRNU and ran...