ubuntu install gstreamer pocketsphinx plugin - No such element or plugin 'pocketshpinx'

[Cindy Chang]

Edited: this problem is solved. Please see my comments below.

Ubuntu version 18 or 16(in my mac)
After installing sphixbase, pocketsphinx（using --prefix=/usr/local/ option when configuring）, and gstreamer, the command
gst-inspect-1.0 pocketsphinx
gave me

No such element or plugin 'pocketshpinx' .

P.S. my GST_PLUGIN_PATH at that time was

/usr/local/lib/gstreamer-1.0

Initially from the config.log I thought it was due to the .pc file not copied at the correct place.
So immediately I ran this copying step before configuring:

$cd /usr/lib/x86_64-linux-gnu/pkgconfig
$cp gstreamer-1.0.pc /home/cindy951357/Downloads/pocketsphinx/src/libpocketsphinx/.libs/
$cp gstreamer-base-1.0 /home/cindy951357/Downloads/pocketsphinx/src/libpocketsphinx/.libs/
$ cp gstreamer-plugins-base-1.0 /home/cindy951357/Downloads/pocketsphinx/src/libpocketsphinx/.libs/

After copying, I re-ran ./configure --prefix=/usr/local/

Now the config.log has no error msg about gstreamer. Then I re-ransudo make install

Afterwards, I re-rangst-inspect-1.0 pocketsphinx
It gave me

No such element or plugin 'pocketshpinx'

Also did:

$sudo cp /usr/local/lib/libpocketsphinx.so /usr/local/lib/gstreamer-1.0/
$sudo cp /usr/local/lib/libpocketsphinx.so.3 /usr/local/lib/gstreamer-1.0/

inside config.log:

configure:13242: checking for GStreamer
configure:13252: $PKG_CONFIG --exists --print-errors "gstreamer-$GST_MAJORMINOR >= 1.0
gstreamer-base-$GST_MAJORMINOR >= 1.0
gstreamer-plugins-base-$GST_MAJORMINOR >= 1.0"
configure:13257: $? = 0
configure:13276: $PKG_CONFIG --exists --print-errors "gstreamer-$GST_MAJORMINOR >= 1.0
gstreamer-base-$GST_MAJORMINOR >= 1.0
gstreamer-plugins-base-$GST_MAJORMINOR >= 1.0"
configure:13281: $? = 0
configure:13323: result: yes

What went wrong? Thanks.

[Cindy Chang]

From another angle,
If I don't copy the three .pc file but use this command

export PKG_CONFIG_PATH=/usr/lib/x86_64-linux-gnu/pkgconfig
the result is that the./config --prefex=/usr/local and make install worked fine. However the inspect command still says the same error:
No such element or plugin 'pocketshpinx' .

[Cindy Chang]

For your information,
Running gst-inspect-1.0 -b, I saw these msgs:
Blacklisted files:
libpocketsphinx.so
libgstpocketsphinx.so

[Cindy Chang]

[solved]
Run

gst-inspect-1.0 /usr/local/lib/gstreamer-1.0/libgstpocketsphinx.so

Then run

gst-inspect-1.0 -b

The libgstpocketsphinx.so is no loger in the blacklist.
Then run

gst-inspect-1.0 pocketsphinx

The terminal outputs message indecating success.