Fix image shape calculation in ToTensor method#90
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This PR fixes how the
ToTensormethod in theBonsai.ML.Torchpackage computes the width of a tensor converted from anIplImage. Previously, the width was derived by dividingWidthStepby the number of channels. However, sinceWidthStepis the row stride in bytes, this calculation is only correct for images with 1-byte element types (U8/S8). For images with wider element types (S16,S32,F32,F64), the computed width was inflated by the element size in bytes, producing a tensor with an incorrect shape that describes more memory than the underlying image buffer actually contains.This PR changes the calculation to first convert the byte stride into an element stride, by dividing
WidthStepby the element size of the input image data type, before dividing by the number of channels. The tensor dimensions are now correctly mapped to the image's data for all supported bit depths, and the resulting tensor no longer overruns the backing buffer.Fixes #88.