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
Source:

decodingConfigCache_ :Map<string, !MediaCapabilitiesDecodingInfo>

A cache of results from mediaCapabilities.decodingInfo, indexed by the (stringified) decodingConfig.
Type:
  • Map<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

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

Parameters:
Name Type Description
variants Array<shaka.extern.Variant>
restrictions shaka.extern.Restrictions
maxHwRes shaka.extern.Resolution
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

chapterStreamToTrack(stream) → {shaka.extern.ChapterTrack}

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

checkEachDecodingConfigCombination_(decodingConfignon-null) → {Promise<?Array<!MediaCapabilitiesDecodingInfo>>}

Parameters:
Name Type Description
decodingConfig MediaDecodingConfiguration
Source:
Returns:
Type
Promise<?Array<!MediaCapabilitiesDecodingInfo>>

checkVariantSupported_(variantnon-null, keySystemnullable, keySystemsMappingnon-null) → {boolean}

Parameters:
Name Type Attributes Description
variant shaka.extern.Variant
keySystem string <nullable>
keySystemsMapping Object<string, string>
Source:
Returns:
Type
boolean

chooseCodecsAndFilterManifest(manifestnon-null, preferredVideoCodecsnon-null, preferredAudioCodecsnon-null, preferredDecodingAttributesnon-null, preferredTextFormatsnon-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>
preferredDecodingAttributes Array<string>
preferredTextFormats Array<string>
Source:

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>

clearDecodingConfigCache()

Clears underlying decoding config cache.
Source:

createEmptyVariant(mimeTypesnon-null) → {shaka.extern.Variant}

Parameters:
Name Type Description
mimeTypes Array<string>
Source:
Returns:
Type
shaka.extern.Variant

createStream(overridesnon-null) → {shaka.extern.Stream}

Creates a Stream object, filling in default values for every field and applying the given overrides on top. This avoids repeating the full set of Stream defaults at the many call sites that build placeholder, dummy or external streams. fullMimeTypes is derived from the resulting mimeType and codecs; streams without a mimeType keep the default empty set.
Parameters:
Name Type Description
overrides Object<string, *>
Source:
Returns:
Type
shaka.extern.Stream

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 shaka.extern.Resolution
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, manifest, preferredKeySystemsopt, non-null, keySystemsMappingopt, non-null)

Alters the given Manifest to filter out any unplayable streams.
Parameters:
Name Type Attributes Description
drmEngine shaka.drm.DrmEngine
manifest shaka.extern.Manifest
preferredKeySystems Array<string> <optional>
keySystemsMapping Object<string, string> <optional>
Source:

filterManifestByCurrentVariant(currentVariantnullable, manifest)

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

filterManifestByMediaCapabilities(drmEngine, manifest, usePersistentLicenses, preferredKeySystemsnon-null, keySystemsMappingnon-null)

Alters the given Manifest to filter out any streams unsupported by the platform via MediaCapabilities.decodingInfo() API.
Parameters:
Name Type Description
drmEngine shaka.drm.DrmEngine
manifest shaka.extern.Manifest
usePersistentLicenses boolean
preferredKeySystems Array<string>
keySystemsMapping Object<string, string>
Source:

filterStreamsByLanguageAndRole(streams, preferredLanguage, preferredRole, preferredForced) → {!Array<!shaka.extern.Stream>|!Array<!shaka.extern.Track>}

Chooses streams according to the given config. Works both for Stream and Track types due to their similarities.
Parameters:
Name Type Description
streams !Array<!shaka.extern.Stream> | !Array<!shaka.extern.Track>
preferredLanguage string
preferredRole string
preferredForced boolean
Source:
Returns:
Type
!Array<!shaka.extern.Stream> | !Array<!shaka.extern.Track>

filterStreamsByRole_(streams, preferredRole) → {!Array<!shaka.extern.Stream>|!Array<!shaka.extern.Track>}

Filter Streams by role. Works both for Stream and Track types due to their similarities.
Parameters:
Name Type Description
streams !Array<!shaka.extern.Stream> | !Array<!shaka.extern.Track>
preferredRole string
Source:
Returns:
Type
!Array<!shaka.extern.Stream> | !Array<!shaka.extern.Track>

filterTextStreams_(manifest)

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

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

Generate a batch of MediaDecodingConfiguration objects to get the decodingInfo results for each variant. Each batch shares the same DRM information, and represents the various fullMimeType combinations of the streams.
Parameters:
Name Type Description
variant shaka.extern.Variant
usePersistentLicenses boolean
srcEquals boolean
Source:
Returns:
Type
Array<!Array<!MediaDecodingConfiguration>>

getDecodingInfosForVariant_(variantnon-null, decodingConfigsnon-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
decodingConfigs Array<!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

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.AudioTrack}

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

html5TextTrackToChapterTrack(textTrack) → {shaka.extern.ChapterTrack}

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

html5TextTrackToTrack(textTrack, textVisibilityopt) → {shaka.extern.TextTrack}

Parameters:
Name Type Attributes Default Description
textTrack TextTrack
textVisibility boolean <optional>
 false
Source:
Returns:
Type
shaka.extern.TextTrack

html5TrackId(html5Track) → {number}

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

html5TrackToShakaTrack(audioTracknullable, videoTracknullable) → {shaka.extern.Track}

Parameters:
Name Type Attributes Description
audioTrack AudioTrack <nullable>
videoTrack VideoTrack <nullable>
Source:
Returns:
Type
shaka.extern.Track

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

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

isAudio(stream) → {boolean}

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

isFastSwitching(variant) → {boolean}

Indicates if some of the variant's streams are fastSwitching.
Parameters:
Name Type Description
variant shaka.extern.Variant
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 shaka.extern.Resolution 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

overrideDolbyVisionCodecs(variantsnon-null)

Maps Dolby Vision codecs to H.264 and H.265 equivalents as a workaround to make Dolby Vision playback work on some platforms. Mapping is done according to the relevant Dolby documentation found here: https://professionalsupport.dolby.com/s/article/How-to-signal-Dolby-Vision-in-MPEG-DASH?language=en_US
Parameters:
Name Type Description
variants Array<!shaka.extern.Variant>
Source:

setBetterIFrameStream(streamnon-null, iFrameStreamsnon-null)

Set the best iframe stream to the original stream.
Parameters:
Name Type Description
stream shaka.extern.Stream
iFrameStreams Array<!shaka.extern.Stream>
Source:

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

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

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

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