I use google to search gst-omx and gstopenmax, but I think that the functionality of two plugins seem to be same. I don't understand what is the relationship between gst-omx and gstopenmax.
According to their individual documentation:
gst-openmax is a GStreamer plug-in that allows communication with OpenMAX IL components.
gst-omx is module that contains a plugin that wraps available OpenMAX IL components and makes them available as standard GStreamer elements.
At above two points I think that they are implementation of OpenMAX IL wrapper. Why implement them by two methods if they are same wrapper for OpenMAX IL? Anybody have any idea for me, thank you to explain this issue for me.
Use gst-omx -> http://cgit.freedesktop.org/gstreamer/gst-omx/
Both aim at providing Openmax IL components features as GStreamer elements. gst-openmax was the first implementation. gst-omx was done later and is maintained by the GStreamer community these days. Not sure what is the status of maintenance of gst-openmax.