transcodedaemon start well but transcode doesn't start after uploading video

[gbcbooks]

/opt/Plone/buildout-cache/eggs/pycrypto-2.4.1-py2.7-linux-x86_64.egg/Crypto/Util/number.py:57: PowmInsecureWarning: Not using mpz_powm_sec. You should rebuild using libgmp >= 5 to avoid timing attack vulnerability.
_warn("Not using mpz_powm_sec. You should rebuild using libgmp >= 5 to avoid timing attack vulnerability.", PowmInsecureWarning)
INFO:collective.transcode:Initializing
INFO:collective.transcode:Launched http channel
INFO:collective.transcode:Launched TranscodeDaemon scheduler thread....
INFO:collective.transcode:Scheduler thread running

i saw some output of /opt/Plone/zinstance/var/log/transcodedaemon-stdout---supervisor-c9zy7d.log
but i do not think that matters.

when will trigger transcodedaemin to transcode video ?