Metadata #169

I'm looking at the TODO, and I'm a bit confused on what some stuff means.

First, by "metadata", I assume you mean stuff like EXIF? If I download this, for example, and then compress it, the EXIF is gone. Again, I assume this is what you mean? CMIIW, though.

Second, this:

When both metadata and data are wanted in the same .xz file, two or more Streams would be concatenated.

Going back to my image example, if an .xz file has just one Stream, does that mean it's only either just the image without the EXIF, or just the EXIF without the actual image?

Thanks.