Grass Valley K2 Edge Protocol Manual v1.0 - Manual (Page 22)

K2 Edge Protocol Manual – document version 1.0 – Page 22
During this life cycle the template instance passes a number of well-defined points such as start or play,
and reaching these points is what we call an event.
The feedback messages described here report on these events via the event field in the feedback
message. Possible field values are shown in the right most column in the table below.
The recognized points in the lifecycle of NRE commands are:
point name phase/type
description fb-event field
value
reception Reception of a command in nexos: acknowledged or not
acknowledged.
ack or nak
start preload Start of the preload phase. Preloading is needed to
prepare assets for immediate start when a template play
is received.
start
error preload Optional errors encountered during preloading, for
example assets that could not be found or have invalid
content. Feedback will only be generated when errors
are encountered.
error
ready preload End of the preload phase. The template is now ready for
playback. If errors were encountered during preload,
playing the template will result in limited functionality.
ready
play playback Start of the template playback phase. play
error playback Errors encountered during playback, for example
problems when accessing new assets needed later
down the time line. Feedback will only be generated
when errors are encountered.
error
safe playback The point in time during playback where a template no
longer depends on new media data and is guaranteed
not to encounter any errors. From this point on, a
template can run forever until stopped.
safe
stop playback The point in time where a template instance is explicitly
or implicitly stopped. At this point the template instance
is removed from memory and can no longer be
accessed.
stop
ready one-shot
commands
One-shot commands not associated with a template
instance (e.g. sub command object-info) only have
two points: the standard reception point and a ready
point that indicates the finish of the short time the
command actually ran.
ready