POIS Conditioning - AWS Elemental Server

This is version 2.15 of the AWS Elemental Server documentation. This is the latest version. For prior versions, see the Previous Versions section of AWS Elemental Conductor File and AWS Elemental Server Documentation.

POIS Conditioning

You can configure AWS Elemental jobs to communicate with a POIS server. During processing of the input, each time a SCTE-35 message is encountered, the AWS Elemental encoder sends the message contents to the server. The POIS responds with SCTE-35 content that may be identical to, slightly different from, or completely different from the original.

The AWS Elemental encoder also supports handling of “out-of-band” SCTE-35 messages from the POIS – messages that are not in response to a message originally sent by the AWS Elemental encoder. If such a message is received, the AWS Elemental encoder accepts and processes it.

Effect of POIS Conditioning

When you enable POIS conditioning, an extra step is inserted into the regular processing of the SCTE-35 messages. The job’s ad avail mode, of manifest decoration, of ad avail blanking, of blackout and of SCTE-35 passthrough still apply to some degree.

You should read the other SCTE-35 topics and the following to determine how POIS conditioning changes the standard behavior.

Ad Avail Mode

When POIS conditioning is enabled, the ad avail mode is always set to “splice insert.” For information about the implications for manifest decoration and ad avail blanking that are performed by the AWS Elemental encoder, see Getting Ready: Setting the Ad Avail Mode.

SCTE-35 Messages Inserted by REST API

All these messages are sent to the POIS along with messages that were already in the input.

New or Conditioned SCTE-35 Messages

The POIS can send an instruction to insert a new SCTE-35 message, modify an existing one, or delete an existing one. A message received from the POIS may include any message type and segmentation type.

Manifest Decoration

The effect of POIS conditioning on manifest decoration is as follows:

  • HLS Outputs – A message received from the POIS may include instructions to decorate an HLS manifest (not other types of manifests). This information is used to decorate the HLS manifest.

    How the AWS Elemental encoder processes the decoration information depends on how the job has been configured:

    • If the job does not have manifest decoration enabled for HLS outputs, then the information is ignored.

    • If the job does have it enabled, then the decoration information is inserted in the manifest.

    • The information is inserted into the manifest “as is.” The style of the information may not match the styles (ad marker styles) specified in the job. The AWS Elemental encoder does not check for format inconsistencies between these instructions and the ad marker style.

  • Other Outputs – Decoration of other manifest types occurs according to the information in the SCTE-35 message, how the AWS Elemental encoder job is set up for manifest decoration, and which ad avail mode is enabled. The POIS conditioning has no effect on these manifest types.

Blanking and Blackout

The effect of POIS conditioning on blanking and blackout is as follows:

  • Extra Blackout Instructions – A message received from the POIS may include explicit “blank the content corresponding to this SCTE-35 message” instructions for any SCTE-35 message.

    Even if blanking or blackout (whichever applies to the message type and segmentation descriptor type) is disabled in the encoder, the AWS Elemental encoder observes the instruction for this specific message.

  • Blanking Image – A POIS response may include reference to a blanking .png or .bmp file. The AWS Elemental encoder uses this file for any blanking/blackout if it can find the file at /data/server/esam/ on the AWS Elemental node.

    If the encoder cannot find the file, it uses a black slate.

  • Restriction Flags – The Override restriction flags in the AWS Elemental job (Ignore Web Delivery Allowed flag and Ignore No Regional Blackout flag) are always set to unchecked in ESAM mode. See Ad Avail Blanking and Blackout.

  • Passthrough or Removal – If passthrough is enabled in the AWS Elemental job, all SCTE-35 messages are passed through, according to the rule.

    But when POIS conditioning is enabled, the POIS can override this rule: if the POIS instruction is to remove a given SCTE-35 message, then that message is removed and is not passed through, even though passthrough is enabled in the AWS Elemental encoder.

Procedure to Enable POIS Conditioning

  1. In the Profile or Job screen, click Advanced Avail Controls (in the Input section towards the top of the screen):

                     The file images/advanced-avail-controls.png.
  2. In Ad Avail Trigger, choose ESAM. More fields appear.

                     The file images/profile-esam.png.
  3. Complete the fields as follows:

    1. Complete the first 6 fields to identify the endpoints on the POIS.

    2. For Response Signal Preroll, change the value as desired, to set the distance (in milliseconds) between the time that the SCTE-35 message is inserted and the start time of that ad avail.