Wegener Communications 6420 user manual Insertion of Audio from Stored Files, Simple File inserts

iPump 6420 User’s Manual

3.4.Insertion of Audio from Stored Files

This section discusses the reason Store/Forward implementers have purchased and deployed WEGENER iPump6420s. The essential function is to allow local file-based content to play in place of the live audio stream, synchronized to overlay specific time epochs we call “spot avails”. These avails are those time periods a default network commercial is playing in the live audio track, as originating in the customer’s automation system, and usually co-located with the uplink compression and control system. The avail becomes the opportunity to play out a locally- relevant commercial spot in substitution, thus offering true “localization”.

3.4.1.Simple File inserts

The iPump6420 can, under Compel or local user command, seamlessly insert the decoded audio from valid files into the decoded audio track from the live satellite PID streams. When a Decoder is set to play live audio from the satellite Transport, defined by Program and Audio LD, then that is called permanent setting, because it is non-volatile, surviving unit resets. File audio inserts, with only special exceptions, are temporary.

The i6420 can execute 1) simple file plays of named files; 2) simple file plays of named files, but with asset alias indirection in the path; 3) or file plays based on keyword indirection into a folder containing a selection of files. It can also play one or more files as part of a playlist, also using the same methods of file identification as just described (see next subsection). For all these file insertions, whether discrete or as part of a playlist, the currently-supported file types are 1) the recorded MPEG program stream files with mpg extensions, 2) MPEG elementary stream files with mp2 extensions, 3) 16-bit PCM wave files with wav extensions, and 4) MPEG I layer 3 files with mp3 extensions (if option is installed, see Section 3.7.4).

When a file is requested to play, its compressed file data will be passed to the audio codec after a time interval following the command, depending on the source. If that source is in- channel Compel, a Command Delay is applied and then decoding begins. For all other sources, the decoding begins virtually immediately, probably less than 50 mS. Remembering the model for the i6420 internal functions (see Figure 1-3), the decoded linear audio data is then passed to a 500 mS deep buffer, creating an automatic 500 mS latency on file plays.* So the system implementer must keep this in mind to avoid confusion: After a Compel file (or playlist) play command, there will be a Compel Command Delay before execution. Then, after execution begins, the old live audio will continue to play for 500 mS before the new file-based audio is heard. The same applies on exiting the file play and return to the live satellite audio stream.

* For purposes of this discussion, it makes no difference whether the file audio is actually compressed-audio data or linear PCM wave-file

data.

Logging: All temporary file plays are logged to the As-run Log.

Relevant indicators are:

1.PLAYBACK LED on during play of any file-based audio, whether temporary or permanent

2.“File-not-found” fault indication

Relevant user controls are:

1.File insertion by named file, by indirection with asset alias (see section 3.4.6), and/or by indirection with keyword-based selection from folder (see section 3.4.5)

2.Abort file play (only a local operation)

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