Automating Tasks with RDCatch
Choosing the Correct Automation Tool
Rivendell includes two modules specially optimized for performing
automatic operations: the RDCatch and RDAirPlay modules. However,
these two
modules take radically different approaches in how they go about
organizing and controlling operations, so a few words regarding
each may be in order here.
RDCatch is aimed at executing actions on the basis of a strict
time-based schedule, referred to as an event list. Each action
(which can be a recording, a
play out, an
upload or download,
a macro execution or an operation on an audio
switcher device) executes on
the basis of its scheduled time in the event list, independently of
all other actions. As such, RDCatch is often best suited for use in
settings such as network head end operations or 'auxiliary' roles at
broadcast stations, where the transitions between events are
generally not an important part of the presentation.
RDAirPlay takes a very different approach, in that most events are
organized into one or more playlists or logs. A Rivendell log is a
list of one or more carts, organized in chronological order. As the
name implies, RDAirPlay is optimized for use in situations where the
transitions between the various program elements are a key part of
the delivery and presentation of the content, such as in live air
play environments.
Of course, it's entirely possible to use both modules, even together
on the same machine at the same time – the Linux OS makes for a very
robust and capable multitasking system. In this chapter, we will
take a look at the capabilities of RDCatch.
The RDCatch Main Window
After starting up RDCatch, you will see the
. The window consists of four
areas: the record / play out decks at the top, the filter areas just
below the decks, the events list and the audition buttons and other
buttons at the bottom. We'll cover each of these in turn.
The Record / Play Out Deck Area
If the system administrator has configured one or more RDCatch
record or play out decks, they will be visible at the top of the
RDCatch main window. A record deck is a virtual 'recorder' that
can be used to make automated recordings, while a play out deck
can be used to automatically play out audio. It does not matter
on which particular host a particular deck resides – all
Rivendell decks throughout the system are visible in RDCatch,
regardless of which host it is run upon.
Starting at the left-hand edge of each deck, there is the deck's
name, consisting of the name of the deck's host machine followed
by a number and a letter, an R
to indicate a record deck and a
P to indicate a play out deck.
Next, for record decks, there is
a MON button, used to monitor the
audio present at the deck input,
followed by an ABORT button, used
to manually stop an event
running in the deck. A description of the currently running event
next appears (this area will be blank if no event is currently
active), followed by the deck's status, which could be any of the
values in .
RDCatch Event States
Status
Meaning
IDLE
The deck is available for events
READY
The deck has started monitoring audio but the transport is
not yet rolling (record decks only).
WAITING
The deck is waiting for a GPI event (record decks only)
RECORDING
The deck is recording (record decks only)
PLAYING
The deck is playing out (play out decks only)
OFFLINE
The deck is configured but not available
The RDCatch Main Window
Finally, each deck has an audio meter on its right-hand end, used
to verify audio levels in realtime.
The Filter Area
Immediately below the decks is the filter area, consisting of the
Show Only Active Events,
Show Only Today's Events
Show DayOfWeek and
Show Event Type
controls, which are used to select which events will be
visible in the events list area immediately below.
The Event List
The event list is a system wide list of all events to be executed
by RDCatch on all of the various hosts on the Rivendell network,
with each event occupying a single line. The status of each event
is indicated by its background color, as shown in
RDCatch Event State Colors
Color
Meaning
YELLOW
The event is next to be executed.
GREEN
The event is active.
CYAN
The event is in the READY state.
VIOLET
The event is in the WAITING state.
RED/PINK
The event is reporting an error.
Each entry in the event list starts with an icon that indicates
the type of the event, as shown in
RDCatch Event Icons
[RECORD_ICON]
Record Event
[PLAYOUT ICON]
Play Out Event
[SWITCH ICON]
Switch Event
[MACRO ICON]
Macro Event
[UPLOAD ICON]
Upload Event
[DOWNLOAD ICON]
Download Event
Next on each line comes the
Description (settable by the user) and
Location for the event, the
location being the name of the host/deck
where the event will run. Then comes the
Start and
End parameters.
These time-based parameters come in one of three different forms:
a hard time, which is simply an absolute time (in twenty-four hour
'military' format), a length (in HH:MM format, relative to an
earlier start time), or a GPI start. The GPI parameters can be
somewhat involved. They are specified in the following format:
Gpi: <start-time>,<end-time>,<gpi-num>,<wait-time>
Where:
<start-time>
The time, in HH:MM:SS format, when RDCatch will start looking
for a GPI event (also sometimes referred to as the window
start time).
<end-time>
The time, in HH:MM:SS format, when RDCatch will stop looking
for a GPI event (also sometime referred to as the window end
time).
<gpi-num>
The number of the GPI event to wait for, in the format
MATRIX:LINE. We will deal with GPI matrix and line numbers
in detail when we cover RDAdmin.
<wait-time>
The amount of time to wait, in MM:SS format, between the
reception of the GPI event and the actual start of the event
(used only for Start parameters).
For example, the start parameter 'Gpi: 14:00:00,14:05:59,0:1,01:00'
has a window start time of 14:00:00 [2:00:00 PM], a window end time
of 14:05:59, looks for a GPI event on line 0:1 and will wait one
minute [01:00] after receiving the GPI before starting the event.
Next come the Source and
Destination fields.
The uses of these will
vary depending upon what type of event is being listed, but should
normally be fairly self-evident. For example, for a record event,
the source field indicates the audio source from which the recording
is to be made, while the destination indicates the cat/cut combo to
which the recording should be made. Some events may leave one or the
other of these fields blank.
Now come the day of the week fields. These indicate on which days
of the week the listed event should be executed, followed by the
Origin field, which is simply a
readout of the Origin data of the
events underlying cut. There are a number of other fields which
follow, but these are less important for understanding the
operation of RDCatch.
The Button Area
At the bottom of the main window are various buttons. On the
left-hand side, the Add,
Edit and
Delete buttons are used to manage
events in the event list. Clicking the
Scroll button toggles
RDCatch into and out of 'scroll mode'. In this mode, the event
list display will be advanced automatically so as to keep the first
actively running event centered within the event list area.
On the right hand side, in addition to
Close, are three audition
buttons. These buttons can be used to audition the head and tail
of each cut referenced by an event, thus making it possible to
quickly verify that a set of automatic recordings were properly
executed.
Adding New Events
A new event can be added to the event list by simply clicking the
Add button to bring up the Add
Event Dialog (see ).
Simply clicking the button that correspond to the desired type of
event will create it.
The Add Event Dialog
Automating Recordings
Automated recordings are configured by means of the Edit Recording
dialog (see ), which can be accessed either by clicking
the Recording button in the Add Event
dialog to create a new record
event or by touching the Edit button
to modify an existing event.
The 'Start Parameters' Section
The start parameters of each recording are configured in the
'Start Parameters' section. A recording can be programmed to start
on the basis of the wall clock time, referred to the hard start
time, or upon reception of a general-purpose input, or GPI event
originated by a satellite receiver, tone decoder or other external
device. Programming a hard start time is merely a matter of
entering the desired start time, in 24 hour 'military' format.
Programming a GPI start involves, in addition to entry of the GPI
parameters themselves (matrix and GPI line numbers) that
Window Start and
Windows End times be entered,
that define the 'window'
during which reception of the appropriate GPI event will be
'recognized' by RDCatch. It is also optionally possible to specify
a Start Delay between reception of
the GPI event and the actual start of the recording.
The Edit Recording Dialog
The 'End Parameters' Section
The end parameters of each recording are configured in the
'End Parameters' section. A recording can be programmed to end on
the basis of a hard time, its absolute length or in response to a
GPI event. Programming of the
Hard Time and
Length parameters
should be fairly self-explanatory, while the parameters needed to
program a GPI event are similar to those used for the start
parameters, with the exception of the
Max Record Length setting,
which limits the maximum length of the recording in the event that
the expected GPI event is never received.
Programming Multiple Recordings in a Single Event
If a record event is configured to use GPI for its start and Length
or GPI for its end parameter, then it is possible to configure the
event to make repeated, multiple recordings within a single event
by checking the
Allow Multiple Recordings Within This Window
box in the 'Start Parameters' section. This can significantly reduce
the amount of required record events when capturing material with
high on-air turnover, such as newscasts or traffic reports.
Selecting a Record Source
If the selected record deck (chosen in the
Location drop-down menu
at the top of the dialog) as been configured to operate with an
audio switcher device, the appropriate audio input can be chosen
from the Source drop-down menu.
Selecting a Record Destination
Each programmed recording must have a 'destination', a designated
Cart/Cut which will hold the audio. The currently programmed
destination is shown in the Destination field, and can be changed
by clicking the Select button.
Setting the Active Days for a Recording
A check should be placed next to each day of the week for which a
recording should be made in the
Active Days box. If no days are
checked, then no recordings at all will be made.
Record List Management with Event Active and Make OneShot
The record event will be actually executed only if
Event Active check box
(in the upper left corner of the dialog box) is ticked. By
clearing this box, it's possible to 'bank' a record event without
actually having it run, useful for events that are only used
sporadically.
For events that need to be executed only once, the
Make OneShot
box can be ticked. Such an event will execute just once, and
then automatically delete itself from the event list.
Automating Playouts
Automated playouts are configured by means of the Edit Playout
dialog (see ), which can be accessed either by
clicking the Playout button in
the Add Event dialog to create a new
record event or by touching the
Edit button to modify an existing
event. The process of configuring a playout is very similar to that
for configuring a recording – see the
above for details.
The Edit Playout Dialog
Automating Uploads/Downloads
It's possible to use RDCatch to automatically upload and download
material from both local and Internet-based servers. Automated
downloads are configured by means of the Edit Download dialog, which
can be accessed either by clicking the
Download button in the Add
Event dialog (see ) to create a new record event or
by touching the Edit button to
modify an existing event.
The Edit Download Dialog
With the exception of the Url,
Username and
Password controls,
the process of configuring a download is very similar to that for
configuring a recording – see the
above for
details.
The Url control is used to specify
the Uniform Resource Locater for
the material to be downloaded. The following download types are
supported: http:,
ftp:, sftp: and
file:. The Url
field can also include
wildcard characters that can be used to construct date-based URLs.
The Username and
Password fields are used to
indicate the username
and password required for access to the server referenced in the
Url.
For public web pages and anonymous FTP servers, these fields can be
left blank.
Automated uploads are configured by means of the Edit Upload dialog
(see ), which can be accessed either by clicking the
Upload button in the Add Event
dialog to create a new record event or
by touching the Edit button to
modify an existing event. The
following upload types are supported: ftp:,
sftp: and file:. As with
downloads, the Url field can also
include wildcard characters that
can be used to construct date-based URLs.
The Edit Upload Dialog
Configuration of an upload event is very similar to that of a download,
with the addition of the
Export Format control.
This is used to set
what file format should be used for the upload. Depending upon what
software encoders have been installed by the system administrator,
the following export types may be available:
PCM16 Linear (*.wav)
Free Lossless Audio Codec [FLAC] (*.flac)
MPEG Layer 2 (*.mp2)
MPEG Layer 3 (*.mp3)
OggVorbis (*.ogg)
The desired upload format and parameters are set by clicking the
Set button.
Automating Macro Execution
It's possible to configure the automatic execution of a Macro Cart
by means of the Edit Cart Event dialog (see ), which
can be accessed either by clicking the
Macro Cart button in the Add
Event dialog to create a new Macro Cart event or by touching the
Edit button to modify an existing
event. The process of configuring
a macro cart event is very similar to that for configuring a
recording – see
above for details.
The Edit Cart Event Dialog
Automating Switcher Operations
It's possible to configure an automatic operation on a switcher
device by means of the Edit Switcher Event dialog (see
), which can be accessed either by clicking the
Switch Event button
in the Add Event dialog to create a new switch event or by touching
the Edit button to modify an
existing event.
The Edit Switcher Event Dialog
In addition to the usual fields, a switch event has
Switch Matrix
(the name of one of the switch matrices associated with the selected
Location),
Switch Input and
Switch Output controls.
When executed, a
switch events causes a take operation to be performed on the specified
switcher device between the specified input and output. It is
possible to specify the input and output either by their alphanumeric
names (assigned in RDAdmin) or by their absolute numbers.