AWS Elemental MediaLive
User Guide

Reference: Identifiers for Variable Data

Identifiers for variable data are $ codes that you can include in a field value to represent variable data. Typically, the variable data (for example, $d$ for the date) is resolved when you run the channel. You can include them in any of the fields that make up part of the output destination:

  • Destination in Output group

  • Name modifier in Output

  • Segment modifier in Output

At runtime, the identifier is resolved to the appropriate data. For example, $dt$ resolves to a date and time.

When you use these identifiers, make sure that the channel doesn't end up with two (or more) outputs with identical destinations. If that happens, the channel passes validation upon creation, but fails on start.

Identifier Format Description
$dt$ YYYYMMDDTHHMMSS UTC date and time of the start time of the channel (for all outputs except HLS) or the date and time of each segment (for HLS outputs).
$d$ YYYYMMDD UTC date of the start time of the channel (for all outputs except HLS) or the date and time of each segment (for HLS outputs).
$t$ HHMMSS Start time of the channel (for all outputs except HLS) or the time of each segment (for HLS outputs).
$rv$ Kb Video bit rate.
$ra$ Kb Total of all audio bit rates in the output.
$rc$ Kb Container bit rate for the output, or the sum of video and all audio bit rates for the output, if the container bit rate is not specified.
$w$ Pixels Horizontal resolution.
$h$ Pixels Vertical resolution.
$f$ Integer FPS Framerate without decimal places. For example, “23.976” appears as “23”.
$$ $ Escaped $.
%0n Padding modifier Modifier for any data identifier. The modifier pads the resolved value with leading zeros. The format is%0n, where n is a number.

For example, to ensure the resolved value in the $h$ identifier is 5 characters long, specify the identifier as $h%05$.

If the vertical resolution is “720”, then the resolved, padded value is “00720”.

The rules for which identifiers can be used in a specified destination field depend on the output type.

Field Applicable Output Types Acceptable Identifiers
Destination in Output group Archive, HLS, Microsoft Smooth $dt$, $d$, $t$
Name modifier in Output Archive, Microsoft Smooth All except $ra$ and $rc$
Name modifier in Output HLS All
Segment modifier in Output Archive, Microsoft Smooth All except $ra$ and $rc$
Segment modifier in Output HLS All