Hi Even, I have seen pretty much everywhere that COG's are created in 3 steps:
1. compress and tile the image $ gdal_translate -co TILED=YES -co COMPRESS=DEFLATE in.tif tmp.tif 2. add overviews $ gdaladdo -r average 2 4 8 16 tmp.tif 3. reorder overviews $ gdal_translate -co TILED=YES -co COMPRESS=DEFLATE -co COPY_SRC_OVERVIEWS=YES tmp.tif out.tif However, it seems that we're tiling and compressing with gdal_translate twice, which doesn't seem to be the most efficient way to do things. I have run some initial tests on an untiled/uncompressed image basically skipping step 1 and going straight to adding overviews and translating to reorder, compress, and tile. The resulting image passes the COG validator test, meaning it is a "valid" COG, though the overview offset values are slightly different: >>> validate(gdal.Open('tile_first_cog.tif')) ... ([], {'ifd_offsets': {'main': 8, 'overview_2': 31886, 'overview_3': 32822, 'overview_0': 18238, 'overview_1': 28966}, 'data_offsets': {'main': 180166631, 'overview_2': 2300609, 'overview_3': 33246, 'overview_0': 45588773, 'overview_1': 11129028}}) >>> validate(gdal.Open('no_init_tile_cog.tif')) ... ([], {'ifd_offsets': {'main': 8, 'overview_2': 31138, 'overview_3': 32074, 'overview_0': 17490, 'overview_1': 28218}, 'data_offsets': {'main': 180165883, 'overview_2': 2299861, 'overview_3': 32498, 'overview_0': 45588025, 'overview_1': 11128280}}) I am wondering, is there any downside to not starting with an initial tiling/compression? -- Sent from: http://osgeo-org.1560.x6.nabble.com/GDAL-Dev-f3742093.html _______________________________________________ gdal-dev mailing list gdal-dev@lists.osgeo.org https://lists.osgeo.org/mailman/listinfo/gdal-dev