加载自定义gstreamer插件会引发gst.ElementNotFoundError

Question

I'm trying to set GST_PLUGIN_PATH environment variable before loading custom gstreamer plugin in an integration test, so I need to change GST_PLUGIN_PATH programmatically.

But without GST_PLUGIN_PATH set in shell, gst.element_factory_make fails.

I'm using gstreamer-0.10, python2.6 and linux 3.2.0 (debian 6).

Example:

import gst, os
os.environ['GST_PLUGIN_PATH'] = '/tmp'
print gst.element_factory_make('myelem')

Without GST_PLUGIN_PATH set in shell:

$ export GST_PLUGIN_PATH=
$ ./gstpathtest.py
Traceback (most recent call last):
  File "./gstpathtest.py", line 7, in <module>
    print gst.element_factory_make('myelem')
gst.ElementNotFoundError: myelem

With GST_PLUGIN_PATH set in shell:

$ GST_PLUGIN_PATH=/tmp ./gstpathtest.py
/MyElem:myelem0 (__main__.MyElem)

or with GST_PLUGIN_PATH exported in shell:

$ export GST_PLUGIN_PATH=/tmp
$ ./gstpathtest.py
/MyElem:myelem0 (__main__.MyElem)

When run with GST_DEBUG=6 I noticed that myelem gets created but is immediately unref-ed and destroyed, which is probably the cause of the error.

I even tried to add the path to os.environ['PATH'] , or directly to sys.path but it didn't change anything.

My main question is: am I doing something wrong on python-level (and what exactly) or does it indicate some bug in the myelem plugin itself?

Answer 1

噢，愚蠢的我-如果我在导入gst之前设置了os.environ['GST_PLUGIN_PATH'] ，那么一切都会按预期进行。

Answer 2

Also, gst.registry.scan_path works:

import gst
gst.registry_get_default().scan_path('/tmp')
print gst.element_factory_make('myelem')