Check extended-square dimensions in a Celestia diagnostic dump
Celestia extends a square along both dimensions. A diagnostic viewer must identify which coordinate space a sample belongs to before interpreting it as application data.
Map an example coordinate
Start with an original square of width eight. The extended width is sixteen, and the original square occupies the upper-left eight-by-eight quadrant. With zero-based indexing, coordinate (2, 11) belongs to the extended area. A tool that labels every coordinate with row less than eight as original will misclassify it.
original square: 8 × 8 = 64 shares
extended square: 16 × 16 = 256 shares
row roots + column roots: 16 + 16 = 32
Compare with the authenticated header
Check the number of row and column roots against the extended width for this block. Even within the original quadrant, protocol data and padding can occur. Recover a user payload with its share format and namespace instead of concatenating every byte of that quadrant.