codec / predictor / lossless

delta_n

Store how values change down each column.

delta_n compares every sample with the one directly above it. The first row stays complete, then each column continues independently. Choose it when values vary smoothly from north to south: the remaining differences are small and easier to compress.

ctid

0x72D702

header

uint32 · row width in samples
+ uint32 · plane count, when above one

widths

8 · 16 · 32 · 64-bit integers

decode

rᵢ + row above, per column