Skip to content
Docs

HLS or DASH over CMAF

Updated View as Markdown

Below are the parameters accessed in the HLS or DASH over CMAF output.

General

General

Parameter Description
Output name

Output name

. The name you want to use for the output.
Naming scheme

Naming scheme for DASH manifests.
Timeline mode: every fragment is listed and requested by the player.
trun v1

Enable trun version 1 for fragments allowing negative CTO (Composition Time Offset) values
Enable thumbnails

Enable thumbnails generation

Related information
HLS or DASH over CMAF output configuration

Dash

Manifest

Parameter Description
Name

Name of the manifest/playlist generated for the current output.

. Default value is index (for HLS) or manifest (for DASH). If a filtering has been applied to the manifest/playlist, it is recommended to use a name that clearly identifies the defined filtering.
Important: The manifest name must be unique and different from any other manifest name.

Filtering - Stream characteristics

Parameter Description
Audio streams filter

Build a filter to select the audio streams that will be included in manifest/playlist.
Applicable filters: bitrate in kbps and Language
Video streams filter

Build a filter to select the video streams that will be included in manifest/playlist.
Applicable filters: bitrate in kbps, codec (H.264 or HEVC) and No video
Subtitle streams filter

Build a filter to select the subtitle streams that will be included in manifest/playlist.
Applicable filters: bitrate in kbps and Language
Thumbnail streams filter

Build a filter to select the thumbnail streams that will be included in manifest/playlist.
Applicable filters: width and height in pixels

Player wall-clock

Parameter Description
Scheme Scheme to use for the UTCTiming element in DASH manifest.
Value Value to use for UTCTiming element depending on the selected scheme.

Notes

  • More than one UTCTiming can be added
  • The urn:mpeg:dash:utc:direct:2014 has no value, the packager will derive it from the stream UTC time

Related information

See UTCTiming below for details on possible values and roles.

HLS

Playlist

Parameter Description
Name

Name of the manifest/playlist generated for the current output.

Default value is index (for HLS) or manifest (for DASH).
Recommendation: If a filtering has been applied to the manifest/playlist, it is recommended to use a name that clearly identifies the defined filtering.

Important: The manifest name must be unique and different from any other manifest name.

Filtering - Stream characteristics

Parameter Description
Audio streams filter

Build a filter to select the audio streams that will be included in manifest/playlist.
Applicable filters: bitrate in kbps and Language
Video streams filter

Build a filter to select the video streams that will be included in manifest/playlist.
Applicable filters: bitrate in kbps, codec (H.264 or HEVC) and No video
Subtitle streams filter

Build a filter to select the subtitle streams that will be included in manifest/playlist.
Applicable filters: bitrate in kbps and Language
Thumbnail streams filter

Build a filter to select the thumbnail streams that will be included in manifest/playlist.
Applicable filters: width and height in pixels

Delivery

General parameters

Parameter Description
Access URL

Portion of the complete access URL that defines the service.


Prefer URI unreserved characters (alphanumerical characters plus (, ), -, _, .). Declaring a subpath (a/b) is possible but may impact performance.
Example: https://[Server IP or FQDN]/packaging/[Output Access URL]/[Live Packaging Service Access URL]/[index.m3u8 OR manifest OR manifest.mpd]

Common encryption (CENC)

Fixed key generation mode

Parameter Description
Key

AES key used for encrypting the content.
Key ID

Identifier used to uniquely identify the key within the system.
PlayReady

Enables PlayReady encryption.
Widevine

Enables Widevine encryption.
Fairplay

Enables Fairplay encryption.

PlayReady mode enabled:

Parameter Description
License acquisition URL

License acquisition URL to be used by the player.
License UI URL

Nonsilent license acquisition URL to be used by the player.
Domain service ID

Domain service identifier.
Microsoft provides a unique identifier to the PlayReady technology supplier.

Widevine mode enabled:

Parameter Description
Provider

Name of the content provider. Also used as the name of the signer.
Policy

Usage rules for the encypted output.

Compatible CPIX ext. key

Parameter Description
Key server URL

URL of the server that will deliver the encryption keys.
PlayReady

Enables PlayReady encryption.
Widevine

Enables Widevine encryption.
Fairplay

Enables Fairplay encryption.
Mediaroom

Enables Mediaroom encryption.
Clearkey Enables Clearkey encryption.

Key rotation

Parameter Description
Enable key rotation

Enable key rotation

. Leaving key rotation disabled means a single key is requested and used for the whole output.
Period

Key rotation period. Choose a value and a unit for the period
Start time

Date and time of the first occurrence

. All crypto periods are aligned on this date and time, modulo the period: it fixes the phase of the period grid rather than the timestamp of an actual, one-time key request.
Time spread

Duration (in seconds) of the time window for spreading key requests out in time

. The actual offset is a pseudo-random value in that window, so it is stable for a given output but different across outputs — this staggers key requests instead of having every channel hit the key server at the same instant.
Period mode

Choose mode for rotation keys.

Possible values are Index and Start/end (default). In Index mode, the CPIX request/response identifies a crypto period by an integer index. In Start/end mode, it is identified by its actual validity window.
Number of key periods to request

Number of key periods to request in advance from the key server

. Requesting more than one fetches the current key plus the upcoming one(s) from the key server in a single round trip; the extra keys are cached and reused so no additional request is needed when the next crypto period starts.

Key usage rules

Parameter Description
Track filters/Filtering

Build a filter to select the streams that will be included in Cpix track.
Applicable filters: streamType (video or audio), width (in pixels), height (in pixels) and codec (H.264 or HEVC)
Track type

Type of a track associated to the track.
Only AZaz09 _,;:@ and space character are accepted
Labels

List of labels associated to the track
Only AZaz09 _,;:@ and space character are accepted
Disable audio encryption

Disables audio encryption for the output.
This setting overrides any encryption setting received from the key provider.

Related information
See CPIX key rotation and track keys below for details on how these settings shape the key requests sent to the key server.

Common encryption (CBCS)

Fixed key generation mode

Parameter Description
Key

AES key used for encrypting the content.

Unit: hexadecimal.
Initialization vector

Initialization vector to be used with the key.
Key ID

Identifier used to uniquely identify the key within the system.
PlayReady

Enables PlayReady encryption.
Widevine

Enables Widevine encryption.
Fairplay

Enables Fairplay encryption.

PlayReady mode enabled:

Parameter Description
License acquisition URL

License acquisition URL to be used by the player.
License UI URL

Nonsilent license acquisition URL to be used by the player.
Domain service ID

Domain service identifier.
Microsoft provides a unique identifier to the PlayReady technology supplier.

Widevine mode enabled:

Parameter Description
Provider

Name of the content provider. Also used as the name of the signer.
Policy

Usage rules for the encypted output.

Fairplay mode enabled:

Parameter Description
URI

URI to be used by the player.
Key format

Specify how the key is declared in the resource specified in the URL.

Key usage rules

Parameter Description
Disable audio encryption

Disables audio encryption for the output.
This setting overrides any encryption setting received from the key provider.

Compatible CPIX ext. key

Parameter Description
Key server URL

URL of the server that will deliver the encryption keys.
PlayReady

Enables PlayReady encryption.
Widevine

Enables Widevine encryption.
Fairplay Enables Fairplay encryption.
Mediaroom

Enables Mediaroom encryption.
Clearkey Enables Clearkey encryption.

Key rotation

Parameter Description
Enable key rotation

Enable key rotation

. Leaving key rotation disabled means a single key is requested and used for the whole output.
Period

Key rotation period. Choose a value and a unit for the period
Start time

Date and time of the first occurrence

. All crypto periods are aligned on this date and time, modulo the period: it fixes the phase of the period grid rather than the timestamp of an actual, one-time key request.
Time spread

Duration (in seconds) of the time window for spreading key requests out in time

. The actual offset is a pseudo-random value in that window, so it is stable for a given output but different across outputs — this staggers key requests instead of having every channel hit the key server at the same instant.
Period mode

Choose mode for rotation keys.

Possible values are Index and Start/end (default). In Index mode, the CPIX request/response identifies a crypto period by an integer index. In Start/end mode, it is identified by its actual validity window.
Number of key periods to request

Number of key periods to request in advance from the key server

. Requesting more than one fetches the current key plus the upcoming one(s) from the key server in a single round trip; the extra keys are cached and reused so no additional request is needed when the next crypto period starts.

Key usage rules

Parameter Description
Track filters/Filtering

Build a filter to select the streams that will be included in Cpix track.
Applicable filters: streamType (video or audio), width (in pixels), height (in pixels) and codec (H.264 or HEVC)
Track type

Type of a track associated to the track.
Only AZaz09 _,;:@ and space character are accepted
Labels

List of labels associated to the track
Only AZaz09 _,;:@ and space character are accepted
Disable audio encryption

Disables audio encryption for the output.
This setting overrides any encryption setting received from the key provider.

CPIX key rotation and track keys

The Compatible CPIX ext. key provider (CENC or CBCS) delegates key generation to an external key server through the DASH-IF CPIX protocol. Two independent CPIX mechanisms are available on top of a single fixed key: key rotation, which periodically requests a new key over time, and track keys, which requests distinct keys for different tracks of the same output.

Key rotation

When key rotation is enabled, the packager requests a new key from the key server for every crypto period instead of a single key for the whole output:

  • The period and its unit set the crypto period duration (converted to seconds for the key request).
  • The start time anchors the period grid: period boundaries fall at start time + n × period, for every integer n. Only the start time's position within one period matters.
  • The time spread adds jitter on top of that grid. Rather than requesting a key exactly on the period boundary, the packager offsets the request by a pseudo-random duration somewhere inside the spread window. This avoids many outputs sharing the same period and start time from all hitting the key server at the same instant, while keeping the offset stable for a given output.
  • The period mode controls how the current crypto period is identified in the CPIX exchange:
    • Index — the request/response carries an integer period number.
    • Start/end (default) — the request/response carries the period's actual validity window.
  • The number of key periods to request lets the packager fetch more than the current key in one CPIX round trip — the current key plus one or more upcoming (lookahead) keys.

Setting the crypto period to 0 (or leaving key rotation disabled) means a single key is requested and used for the entire output — none of the other key rotation parameters apply in that case.

Track keys

By default, a single CPIX key applies to every track of an output. Declaring one or more entries in Tracks requests one key per entry instead, so different tracks (e.g. UHD video vs. SD video vs. audio) can be encrypted with different keys — a common requirement for tiered DRM policies (for example restricting 4K playback to devices with a stronger security level).

Each track entry combines two independent things:

  • Track type and Labels are sent to the key server as the CPIX usage rule for that track's key. Both are free-form strings with no built-in normalization — their meaning is a convention agreed with the key server.
  • Filtering is evaluated locally by the packager only — it is never sent to the key server — to decide which of the output's actual streams that track key applies to. It supports streamType (video or audio), width and height (in pixels), and codec (H.264 or HEVC). The first track whose filter matches a given stream wins; a track without any filtering has no local restriction.

Important: the key server may return a different key ID and key periods than the one the packager sent for a given track — always match tracks and keys on the identity returned in the CPIX response, not on the request.

Combining key rotation with track keys

Key rotation and track keys can be combined: the packager then requests one key per (track, crypto period) combination — for example, 2 tracks with 3 lookahead periods results in 6 keys in a single CPIX exchange. In that case, each <ContentKeyUsageRule> additionally carries a <KeyPeriodFilter periodId="…"/> element tying that specific track's key to the crypto period it is valid for.

Related information
HLS or DASH over CMAF output configuration
HLS over TS output configuration

UTCTiming

The <UTCTiming> element of the MPD tells a DASH client how to synchronize its clock with the server's wall-clock time. For live streams, the client needs this reference to compute which segment is currently available at the live edge, using availabilityStartTime, timeShiftBufferDepth and suggestedPresentationDelay. Without it, a client with a drifting local clock can request segments that do not exist yet or that have already left the time-shift window. UTCTiming is defined in ISO/IEC 23009-1 (MPEG-DASH), clause 5.8.4.11 "UTC timing scheme" and can appear zero or more times as a child of the MPD element:

  <UTCTiming schemeIdUri="urn:mpeg:dash:utc:http-xsdate:2014" value="https://time.example.com/xsdate"/>
Attribute Description
schemeIdUri Required. A URN that identifies the method the client uses to obtain the time.
value Scheme-specific. For most schemes this is one or more URLs (or host names) to query. For direct, it is the UTC time from the input stream.
id Optional. Identifier of the descriptor, not supported in the packager

When several UTCTiming elements are present, they are listed in order of preference: the client should try the first scheme it supports and fall back to the next ones if the request fails.

The schemes defined by the specification are:

schemeIdUri value Description
urn:mpeg:dash:utc:ntp:2014 NTP server host name(s), space separated The client obtains the time using the NTP protocol (RFC 5905).
urn:mpeg:dash:utc:sntp:2014 SNTP server host name(s), space separated The client obtains the time using the SNTP protocol (RFC 4330).
urn:mpeg:dash:utc:http-head:2014 URL, space separated if several The client issues an HTTP HEAD request and reads the time from the Date response header.
urn:mpeg:dash:utc:http-xsdate:2014 URL, space separated if several The client issues an HTTP GET request. The body is the time as an xs:dateTime string (for example 2024-01-01T12:00:00.123Z).
urn:mpeg:dash:utc:http-iso:2014 URL, space separated if several The client issues an HTTP GET request. The body is the time in ISO 8601 format.
urn:mpeg:dash:utc:http-ntp:2014 URL, space separated if several The client issues an HTTP GET request. The body is a 64-bit NTP timestamp (RFC 5905 format).
urn:mpeg:dash:utc:direct:2014 UTC time as xs:dateTime The time is carried directly in the MPD. It is only as accurate as the delay between MPD generation and reception, so it should be used only if no other scheme is available.

Related information

Edit this page
Navigation