1484242 - Limit the number of simultaneously active decoders when using MediaCapabilities

Status: RESOLVED FIXED

(Core :: Audio/Video: Playback, enhancement, P2)

Description

[Jean-Yves Avenard [:jya]]

Each request to MediaCapabilities.decodingInfo will potentially create a decoder in order to determine if the video is hardware accelerated or not.

On Android, where the device could have a set number of decoders active, it may cause some problems.

We should limit the number of active decoders, potentially serialising all the request.

Comment 1

[Jean-Yves Avenard [:jya]]

Attachment: Bug 1484242 - P1. Add AllocationPolicy objects. r?bryce

We extract the GlobalAllocationPolicy and the MediaDataDecoder wrapper from MediaFormatReader.

They will be used to create a new wrapping class that will serialize allocation and initalization of decoders if the platform requires it.

Comment 2

[Jean-Yves Avenard [:jya]]

Attachment: Bug 1484242 - P2. Add CreateDecoderParams copy constructor. r?bryce

We also makes mTaskQueue and mImageContainer members a RefPtr to prevent invalid use where those members could be destroyed before they were used.

Depends on D3676

Comment 3

[Jean-Yves Avenard [:jya]]

Attachment: Bug 1484242 - P2. Add AllocationWrapper::CreateDecoder convenience method. r?bryce

This method will allocate a decoder according to the GlobalAllocPolicy. On Android API 18 and lower, there can only be a single decoder created at a time. The promise returned by CreateDecoder will only be resolved once the allocation policy permits a new decoder to be created.

Depends on D3677

Comment 4

[Jean-Yves Avenard [:jya]]

Attachment: Bug 1484242 - P3. Have MediaCapablities use GlobalAllocPolicy for creating decoders. r?bryce

This ensures on platform that requires it, that only a single decoder at a time are used, in effect serialising all the MediaCapabilities.decodingInfo requests.

Depends on D3678

Comment 5

[Bryce Seager van Dyk [:bryce] (he/him) - Not reading bugmail]

Comment on attachment 9002148 [details]
Bug 1484242 - P1. Add AllocationPolicy objects. r?bryce

Bryce Seager van Dyk (:bryce) has approved the revision.

Comment 6

[Bryce Seager van Dyk [:bryce] (he/him) - Not reading bugmail]

Comment on attachment 9002150 [details]
Bug 1484242 - P2. Add AllocationWrapper::CreateDecoder convenience method. r?bryce

Bryce Seager van Dyk (:bryce) has approved the revision.

Comment 7

[Bryce Seager van Dyk [:bryce] (he/him) - Not reading bugmail]

Comment on attachment 9002151 [details]
Bug 1484242 - P3. Have MediaCapablities use GlobalAllocPolicy for creating decoders. r?bryce

Bryce Seager van Dyk (:bryce) has approved the revision.

Comment 8

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/mozilla-inbound/rev/80e04deb3282
P1. Add AllocationPolicy objects. r=bryce
https://hg.mozilla.org/integration/mozilla-inbound/rev/114dacc6e603
P2. Add AllocationWrapper::CreateDecoder convenience method. r=bryce
https://hg.mozilla.org/integration/mozilla-inbound/rev/5b802b94d59f
P3. Have MediaCapablities use GlobalAllocPolicy for creating decoders. r=bryce

Comment 9

[Tiberius Oros[:tiberius_oros]]

https://hg.mozilla.org/mozilla-central/rev/80e04deb3282
https://hg.mozilla.org/mozilla-central/rev/114dacc6e603
https://hg.mozilla.org/mozilla-central/rev/5b802b94d59f