Class: shaka.util.StreamUtils

A set of utility functions for dealing with Streams and Manifests.

Constructor

new StreamUtils()

A set of utility functions for dealing with Streams and Manifests.

Source:

Members

DecodingAttributes :string

Type:
  • string
Properties:
Name Value Type Description
SMOOTH smooth string
POWER powerEfficient string
BANDWIDTH bandwidth string
Source:

decodingConfigCache_ :Object.<(!string), (!MediaCapabilitiesDecodingInfo)>

A cache of results from mediaCapabilities.decodingInfo, indexed by the (stringified) decodingConfig.
Type:
  • Object.<(!string), (!MediaCapabilitiesDecodingInfo)>
Source:

minAvifImage_ :string

Type:
  • string
Source:

minImage_ :Map.<string, string>

Type:
  • Map.<string, string>
Source:

minWebPImage_ :string

Type:
  • string
Source:

nextTrackId_ :number

Type:
  • number
Source:

supportedImageMimeTypes_ :Map.<string, boolean>

Type:
  • Map.<string, boolean>
Source:

Methods

alphabeticalKeyOrderStringify_(objnon-null) → {string}

Constructs a string out of an object, similar to the JSON.stringify method. Unlike that method, this guarantees that the order of the keys is alphabetical, so it can be used as a way to reliably compare two objects.
Parameters:
Name Type Description
obj Object
Source:
Returns:
Type
string

applyRestrictions(variantsnon-null, restrictions, maxHwRes) → {boolean}

Parameters:
Name Type Description
variants Array.<shaka.extern.Variant>
restrictions shaka.extern.Restrictions
maxHwRes {width: number, height: number}
Source:
Returns:
Whether the tracks changed.
Type
boolean

areStreamsCompatible_(s0, s1) → {boolean}

Parameters:
Name Type Description
s0 shaka.extern.Stream
s1 shaka.extern.Stream
Source:
Returns:
Type
boolean

chooseCodecsAndFilterManifest(manifestnon-null, preferredVideoCodecsnon-null, preferredAudioCodecsnon-null, preferredAudioChannelCount, preferredDecodingAttributesnon-null)

In case of multiple usable codecs, choose one based on lowest average bandwidth and filter out the rest. Also filters out variants that have too many audio channels.
Parameters:
Name Type Description
manifest shaka.extern.Manifest
preferredVideoCodecs Array.<string>
preferredAudioCodecs Array.<string>
preferredAudioChannelCount number
preferredDecodingAttributes Array.<string>
Source:

chooseCodecsByDecodingAttributes_(variantsByCodecsnon-null, attributesnon-null) → {string}

Choose the codecs by configured preferred decoding attributes.
Parameters:
Name Type Description
variantsByCodecs shaka.util.MultiMap.<shaka.extern.Variant>
attributes Array.<string>
Source:
Returns:
Type
string

chooseCodecsByMediaCapabilitiesInfo_(variantsByCodecsnon-null, attribute) → {shaka.util.MultiMap.<shaka.extern.Variant>}

Choose the best codecs by configured preferred MediaCapabilitiesInfo attributes.
Parameters:
Name Type Description
variantsByCodecs shaka.util.MultiMap.<shaka.extern.Variant>
attribute string
Source:
Returns:
Type
shaka.util.MultiMap.<shaka.extern.Variant>

choosePreferredCodecs(variantsnon-null, preferredVideoCodecsnon-null, preferredAudioCodecsnon-null) → {Array.<shaka.extern.Variant>}

Choose the codecs by configured preferred audio and video codecs.
Parameters:
Name Type Description
variants Array.<shaka.extern.Variant>
preferredVideoCodecs Array.<string>
preferredAudioCodecs Array.<string>
Source:
Returns:
Type
Array.<shaka.extern.Variant>

filterByRestrictions(manifestnon-null, restrictions, maxHwResolution)

Filter the variants in |manifest| to only include the variants that meet the given restrictions.
Parameters:
Name Type Description
manifest shaka.extern.Manifest
restrictions shaka.extern.Restrictions
maxHwResolution {width: number, height:number}
Source:

filterImageStreams_(manifest)

Alters the given Manifest to filter out any unsupported image streams.
Parameters:
Name Type Description
manifest shaka.extern.Manifest
Source:

filterManifest(drmEngine, currentVariantnullable, manifest)

Alters the given Manifest to filter out any unplayable streams.
Parameters:
Name Type Attributes Description
drmEngine shaka.media.DrmEngine
currentVariant shaka.extern.Variant <nullable>
manifest shaka.extern.Manifest
Source:

filterManifestByCurrentVariant(currentVariantnullable, manifest)

Alters the given Manifest to filter out any streams uncompatible with the current variant.
Parameters:
Name Type Attributes Description
currentVariant shaka.extern.Variant <nullable>
manifest shaka.extern.Manifest
Source:

filterManifestByMediaCapabilities(manifest, usePersistentLicenses)

Alters the given Manifest to filter out any streams unsupported by the platform via MediaCapabilities.decodingInfo() API.
Parameters:
Name Type Description
manifest shaka.extern.Manifest
usePersistentLicenses boolean
Source:

filterStreamsByLanguageAndRole(streamsnon-null, preferredLanguage, preferredRole, preferredForced) → {Array.<!shaka.extern.Stream>}

Chooses streams according to the given config.
Parameters:
Name Type Description
streams Array.<shaka.extern.Stream>
preferredLanguage string
preferredRole string
preferredForced boolean
Source:
Returns:
Type
Array.<!shaka.extern.Stream>

filterTextStreams_(manifest)

Alters the given Manifest to filter out any unsupported text streams.
Parameters:
Name Type Description
manifest shaka.extern.Manifest
Source:

filterTextStreamsByRole_(textStreamsnon-null, preferredRole) → {Array.<shaka.extern.Stream>}

Filter text Streams by role.
Parameters:
Name Type Description
textStreams Array.<shaka.extern.Stream>
preferredRole string
Source:
Returns:
Type
Array.<shaka.extern.Stream>

filterVariantsByAudioChannelCount(variantsnon-null, preferredAudioChannelCount) → {Array.<!shaka.extern.Variant>}

Filters variants according to the given audio channel count config.
Parameters:
Name Type Description
variants Array.<shaka.extern.Variant>
preferredAudioChannelCount number
Source:
Returns:
Type
Array.<!shaka.extern.Variant>

filterVariantsByDensity_(variantsByCodecsnon-null) → {shaka.util.MultiMap.<shaka.extern.Variant>}

Filters variants by density. Get variants by codecs map with the max density where all codecs are present.
Parameters:
Name Type Description
variantsByCodecs shaka.util.MultiMap.<shaka.extern.Variant>
Source:
Returns:
Type
shaka.util.MultiMap.<shaka.extern.Variant>

findCodecsByLowestBandwidth_(variantsByCodecsnon-null) → {string}

Find the lowest-bandwidth (best) codecs. Compute the average bandwidth for each group of variants.
Parameters:
Name Type Description
variantsByCodecs shaka.util.MultiMap.<shaka.extern.Variant>
Source:
Returns:
Type
string

getCorrectAudioCodecs_(codecs) → {string}

Generates the correct audio codec for MediaDecodingConfiguration and for MediaSource.isTypeSupported.
Parameters:
Name Type Description
codecs string
Source:
Returns:
Type
string

getCorrectVideoCodecs_(codec) → {string}

Generates the correct video codec for MediaDecodingConfiguration and for MediaSource.isTypeSupported.
Parameters:
Name Type Description
codec string
Source:
Returns:
Type
string

getDecodingConfigs_(variantnon-null, usePersistentLicenses, srcEquals) → {Array.<!MediaDecodingConfiguration>}

Generate a MediaDecodingConfiguration object to get the decodingInfo results for each variant.
Parameters:
Name Type Description
variant shaka.extern.Variant
usePersistentLicenses boolean
srcEquals boolean
Source:
Returns:
Type
Array.<!MediaDecodingConfiguration>

getDecodingInfosForVariant_(variantnon-null, decodingConfignon-null)

Queries mediaCapabilities for the decoding info for that decoding config, and assigns it to the given variant. If that query has been done before, instead return a cached result.
Parameters:
Name Type Description
variant shaka.extern.Variant
decodingConfig MediaDecodingConfiguration
Source:

getDecodingInfosForVariants(variantsnon-null, usePersistentLicenses, srcEquals, preferredKeySystemsnon-null)

Get the decodingInfo results of the variants via MediaCapabilities. This should be called after the DrmEngine is created and configured, and before DrmEngine sets the mediaKeys.
Parameters:
Name Type Description
variants Array.<shaka.extern.Variant>
usePersistentLicenses boolean
srcEquals boolean
preferredKeySystems Array.<string>
Source:

getPlayableVariants(variantsnon-null) → {Array.<!shaka.extern.Variant>}

Filters out unplayable variants.
Parameters:
Name Type Description
variants Array.<!shaka.extern.Variant>
Source:
Returns:
Type
Array.<!shaka.extern.Variant>

getStreamSummaryString_(stream) → {string}

Returns a string of an audio or video stream for log printing.
Parameters:
Name Type Description
stream shaka.extern.Stream
Source:
Returns:
Type
string

getVariantCodecs_(variantnon-null) → {string}

Get a string representing all codecs used in a variant.
Parameters:
Name Type Description
variant shaka.extern.Variant
Source:
Returns:
Type
string

getVariantsByCodecs_(variantsnon-null) → {shaka.util.MultiMap.<shaka.extern.Variant>}

Get variants by codecs.
Parameters:
Name Type Description
variants Array.<shaka.extern.Variant>
Source:
Returns:
Type
shaka.util.MultiMap.<shaka.extern.Variant>

getVariantStreams(variant) → {Array.<shaka.extern.Stream>}

Get all non-null streams in the variant as an array.
Parameters:
Name Type Description
variant shaka.extern.Variant
Source:
Returns:
Type
Array.<shaka.extern.Stream>

getVariantSummaryString_(variant) → {string}

Returns a string of a variant, with the attribute values of its audio and/or video streams for log printing.
Parameters:
Name Type Description
variant shaka.extern.Variant
Source:
Returns:
Type
string

html5AudioTrackToTrack(audioTrack) → {shaka.extern.Track}

Parameters:
Name Type Description
audioTrack AudioTrack
Source:
Returns:
Type
shaka.extern.Track

html5TextTrackToTrack(textTrack) → {shaka.extern.Track}

Parameters:
Name Type Description
textTrack TextTrack
Source:
Returns:
Type
shaka.extern.Track

html5TrackId(html5Track) → {number}

Generate and return an ID for this track, since the ID field is optional.
Parameters:
Name Type Description
html5Track TextTrack | AudioTrack
Source:
Returns:
The generated ID.
Type
number

html5TrackToGenericShakaTrack_(html5Track) → {shaka.extern.Track}

Creates a Track object with non-type specific fields filled out. The caller is responsible for completing the Track object with any type-specific information (audio or text).
Parameters:
Name Type Description
html5Track TextTrack | AudioTrack
Source:
Returns:
Type
shaka.extern.Track

imageStreamToTrack(stream) → {shaka.extern.Track}

Parameters:
Name Type Description
stream shaka.extern.Stream
Source:
Returns:
Type
shaka.extern.Track

isAudio(stream) → {boolean}

Checks if the given stream is an audio stream.
Parameters:
Name Type Description
stream shaka.extern.Stream
Source:
Returns:
Type
boolean

isImageSupported_(minImage) → {Promise.<boolean>}

Parameters:
Name Type Description
minImage string
Source:
Returns:
Type
Promise.<boolean>

isPlayable(variantnon-null) → {boolean}

Determines if the given variant is playable.
Parameters:
Name Type Description
variant shaka.extern.Variant
Source:
Returns:
Type
boolean

isVideo(stream) → {boolean}

Checks if the given stream is a video stream.
Parameters:
Name Type Description
stream shaka.extern.Stream
Source:
Returns:
Type
boolean

meetsRestrictions(variant, restrictions, maxHwRes) → {boolean}

Parameters:
Name Type Description
variant shaka.extern.Variant
restrictions shaka.extern.Restrictions Configured restrictions from the user.
maxHwRes {width: number, height: number} The maximum resolution the hardware can handle. This is applied separately from user restrictions because the setting should not be easily replaced by the user's configuration.
Source:
Returns:
Type
boolean

textStreamToTrack(stream) → {shaka.extern.Track}

Parameters:
Name Type Description
stream shaka.extern.Stream
Source:
Returns:
Type
shaka.extern.Track

variantToTrack(variant) → {shaka.extern.Track}

Parameters:
Name Type Description
variant shaka.extern.Variant
Source:
Returns:
Type
shaka.extern.Track