Manually dropping video frame in element

[Ryan Brigden]

What you suggest is a nice solution given that the wrapper can be
shared from a single crate. We've put together an example that adapts
the CustomMetaAPI example in gstreamer-rs [1] to our current approach.

The master branch of the example repo reproduces the double meta api
initialization error [2].

Another branch [3] of this repo contains our attempt to resolve the
issue by separating the implementation (gst-meta-imp), which is built
as a dylib, and wrapper (gst-meta). The example in this branch also
includes a plugin that uses the custom meta.

In [3], the custom_meta example (in the gst-meta crate) runs fine, but
the test_pipeline fails with the error:
./target/release/test_pipeline: error while loading shared libraries:
libstd-e12de7683a34c500.so: cannot open shared object file: No such
file or directory

We're not sure what exactly requires a libstd shared object? Perhaps
we are taking the incorrect approach here?

Thanks again

[1]: https://gitlab.freedesktop.org/gstreamer/gstreamer-rs/-/blob/master/examples/src/bin/custom_meta.rs
[2]: https://gitlab.freedesktop.org/alex4/gstmeta-test-case/-/tree/master
[3]: https://gitlab.freedesktop.org/alex4/gstmeta-test-case/-/tree/attempt-dynamic-linking