Median Compression Ratio
DEMzip (no options)
DEMzip (-epsg, -nodata_min)
GDAL GTiff (COMPRESS=LZW, PREDICTOR=2)
GDAL GTiff (COMPRESS=LZW, PREDICTOR=3)
GDAL GTiff (COMPRESS=LZW, PREDICTOR=3, DISCARD_LSB=12)
GDAL GTiff (COMPRESS=ZSTD, PREDICTOR=3)
GDAL GTiff (COMPRESS=LERC_ZSTD, PREDICTOR=3, MAZ_Z_ERROR=0.01)
GDAL GTiff (COMPRESS=LERC_ZSTD, PREDICTOR=3, MAZ_Z_ERROR=0.01, DISCARD_LSB=12)
He writes that "the only compressor that occasionally beats DEMzip is the very dangerous “only use if you know what you’re doing” LZW with predictor 3 and discarding the least significant 12 bits, which also produces somewhat unreliable results (I only guessed at the 12 bits instead of actually thinking about it). So DEMzip with NODATA removal is by far the best compression tested."
Thank you, Nathanael, for these excellent experiments.
[src_min src_max [dst_min dst_max]]