What is Element 84's perspective on when to use Zarr versus Cloud-Optimized GeoTIFF (COG) formats for geospatial data? Additionally, identify two open-source technologies or standards that Element 84 mentions contributing to or being involved with, based on their blog's recommended topics.
Navigate to the 'Blog' section of the website. Use the search bar to find the blog post 'Is Zarr the new COG?'. Extract Element 84's perspective on the use cases for Zarr and COG from the search result snippet. Identify two open-source technologies or standards listed under 'Recommended topics' on the blog page.
State that Element 84 views Zarr and COG as complementary, with Zarr being suitable for Level 3 and Level 4 n-dimensional data cubes, and COG for Level 1, Level 2, and other non-data-cube rasters. List two distinct open-source technologies or standards from the 'Recommended topics' section of the blog (e.g., STAC, Raster Vision, Open Source).