README: please add about compression: is it enabled by default? For all file formats?

[vitaly-zdanevich]

Can we regulate compression ratio? What is the compression format?

[benoit74]

There is nothing special about this in the zimit scraper, we just use regular mechanisms of the libzim. Transferring issue there.

[rgaudin]

Here's the details if you want to submit a PR for that

• Compression method is chosen a ZIM creation time.
• A ZIM can only use one compression method.
• libzim currently only supports zstd (zstandard) and none (no compression at all for any entries)
• Compression is per entry ; not the whole thing
• ZIM creator can choose to compress or not compress any entry when adding to ZIM
• When adding an entry, if compression information is not supplied, a decision is made automatically:
  • if mimetype of entry to be added starts with text/, then it is compressed
  • if not, it is not compressed.

[vitaly-zdanevich]

Thanks, created PR openzim/zimit#459