Plugin prefix not great

[Artoria2e5]

The plugin path is currently hardcoded to be $PREFIX/lib/gstreamer-1.0. This is not great in a number of cases:

• When gstreamer and gstpeaq are in different prefixes. When trying out a package, I tend to put it in /usr/local, which is not where gstreamer is (/usr).
• When gestreamer has a multilib plugin path. On Debian, the actual plugin path is /lib/x86_64-linux-gnu/gstreamer-1.0/.

There are two ways to work around that:

• The system-wide way is to find the real plugin dir with pkg-config --variable=pluginsdir gstreamer-1.0.
• The user-level way is to drop the thing in ~/.local/share/gstreamer-1.0/plugins. I actually made it a symlink to /usr/local/lib/gstreamer-1.0, which works well so far.

[martinholters]

Hm, yeah, that is not great. I'm using https://github.com/GStreamer/common/blob/52adcdb89a9eb527df38c569539d95c1c7aeda6e/m4/gst-plugindir.m4 (copied in verbatim to https://github.com/HSU-ANT/gstpeaq/blob/0b9315ecdaac6440db757eed8eabfa0cfc7dfd8e/m4/gst-plugindir.m4) which I hoped would do the right thing. OTOH, it's not entirely clear that with the prefix being e.g. /usr/local, the user would really likes to have anything installed outside of it. I'm not sure what the best behavior is here, but tend to keep it as is, where if you want to install most of gstpeaq in /usr/local, but the plugin somewhere else, you need to supply libdir, e.g. ./configure --libdir=/lib/x86_64-linux-gnu . This is already mentioned in the docs:

https://github.com/HSU-ANT/gstpeaq/blob/0b9315ecdaac6440db757eed8eabfa0cfc7dfd8e/INSTALL#L16-L20

But also mentioning --libdir=$(dirname $(pkg-config --variable=pluginsdir gstreamer-1.0)) there could be helpful, thanks for bringing it up.

It might also be a good idea to check whether the plugin installation path is something where Gstreamer will look and print a warning otherwise, either during configure or make. Not everyone reads the docs first, after all...