| 1 | preview
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| - Note that the preview parameter has a nested-cumulative behaviour, i. e. if one specifies VoCentering's preview parameter together with NxtomoLoader's preview parameter, then VoCentering will effectively be selecting a subset from NxtomoLoader's own subset (rather than the entire dataset). Note also that VoCentering's subset must always be specified by indexing NxtomoLoader's own subset (rather than the entire dataset). For instance, one must set VoCentering's preview parameter to [:, 0, :] in order to select the initial slice of any dataset previously loaded by NxtomoLoader, which may, for example, be the [:, 123:456, :] subset of the entire dataset.
- If you use any kind of parameter tuning before applying VoCentering, then the latter will automatically receive (from the immediately preceding process) a dataset of order higher than 3, in which case you must slice the incoming dataset by specifying the preview parameter of VoCentering in such a way as to generate a desired rank-3 sub-set of that higher-rank dataset. For instance, if you generate have generated a new dataset of shape (D, img_W, img_L, T) by applying a single parameter-tuning operation to the original (D, img_W, img_L) data, then this new, rank-4 dataset needs to be sliced in the last dimension, e. g. if the preview parameter of VoCentering is set to be the [:, mid, :, 0] slice of the parameter-tuned dataset, then the resulting rank-3 subset selects the middle slice sinogram from (D, img_W, img_L), corresponding to the first initial value of the tuning parameter.
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| 3 | search_area
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| If the value of the search_area parameter is set to the default interval of (-50, 50), then VoCentering will attempt to search for an optimal value of CoR in the (start_pixel - 50, start_pixel + 50) interval. For some datasets, this default range of search (100 pixel) may be not sufficiently large to include an optimal value of CoR, leading to subsequent sub-optimal reconstruction. Therefore, if the value of CoR determined by VoCentering is found to coincide with one of the search-interval limits (i. e. either start_pixel - 50 or start_pixel + 50), then this value of CoR may not necessarily be optimal, and one should then re-run VoCentering with a larger value of the search_area parameter to confirm this result. |