In MSparkles, the filter size is specified via a filter'S kernel half-size parameter. The actual filter size is then computed as 2*HalfSize+1. This ensures, an odd size of the filter which is computationally advantageous, since is ensures the existance of a central element within the filter kernel and avoids additional interpolations. Especially for median filters this is advantageous, since it does not introduce new values and helps preserve sharp edges of structures within an image or signal.
For more details on image filtering, please refer to the MATLAB help.
Filter name | Parameters |
---|---|
Spatial Gauss filter Temporal Gauss filter |
A Gaussian smoothing filters uses a Gauss-curve as weighting function for the pixels covered by the filter kernel. Typically the kernel half-size is 3*sigma |
Spatial median filter Temporal median filter |
The median filter sorts the values within the filter window in ascending order and chooses the central element (median) as local answer of the filter. |
Spatial boxcar filter Temporal boxcar filter |
The boxcar (or mean filter) computed the mean grey value of the pixels within the filter window as to local answer of the filter. |
Stack registration |
Automated, intensity-based stack registration. Imagees are aligned with respect to a reference frame and a reference channel. After registration the stack is automatically cropped and meta data are updated (if neccessary). |
SURE-LET denoising | Automated, per frame denoising, using the SURE-LET algorithm. |
Linear unmixing | Linear unmixing of multi-channel images, based on a least-squares algorithm. |
Temporal Savitzky-Golay filter |
Polynomial smoothing of 1D, time-dependent signals. Order specifies the order of the fitted polynom within the filter window. Order must be less then the length of the filter window (KernelHalfSize*2+1). See MATLAB help for more details. |