wiki:April 2012 HTML5 Media Element & WebAudio

Version 1 (modified by, 12 years ago) (diff)

Initial Commit

Agenda Items / Topics

  • Status of Tracks
  • Update on Buffering & LayoutTests
  • Status of MediaPlayer{QTKit,AVFoundation,GTK}.
  • Media Source
  • Encrypted Media W3C Spec
  • WebAudio


Eric Carlson :ericc

  • W3C spec is mostly implemented
    • Unimplemented:
      • Rendering
      • word-wrapping (unsettled in the W3C spec)
      • native controls do not yet control TextTracks (selection, enabling, etc.)
    • Implemented:
      • Basic rendering
      • Basic functionality
    • Available in WebKit nightlies behind a runtime flag
    • IE10 has implemented it as well
      • Only basic rendering

Update on Buffering & LayoutTests

Andrew Scherkus :scherkus

  • In the last year
    • Bug fixes
    • HTTP Media Layout Tests for handling a variety of Servers
      • e.g. Buggy support of Range Requests
      • Edge cases of server support
    • Should these layout tests be in http/tests/media, or in an alternate test suite?
      • ericc: would love to have these tests checked in
    • What should these tests assert?
      • buffered attribute?
      • seekable attribute?
  • Resource Loader changes
    • Chromium: AssociatedURLLoader
  • URLs

Status of MediaPlayer{QTKit,AVFoundation,GTK}

Alexis Menard :darktears

  • Qt currently uses MediaPlayerPrivateQTKit
  • AVFoundation is the future media framework on Mac platform
  • CALayers:
    • Qt does not currently support Accelerated Compositing
    • MPPQTKit & MPPAVFoundation makes assumptions about the type of PlatformLayer
    • MPPAVFoundation is separated into an ObjectiveC and a C++ implementation
      • Beneficial for Qt port.
    • used in the three ports
    • upcoming work:
      • accelerated decoding and rendering
      • currently works both on WebKit & WebKit2.
      • should GTK adopt the Media Source API?

Media Source API

Aaron Caldwell

  • proposed to the W3C
  • primary use case is adaptive streaming
  • most recent spec is an upgrade to the original, simpler spec.
  • Currently updating WebKit to match the new spec
  • Support both WebM and ISO (MP4) formats.
  • Want to migrate code from the Chrome port into WebKit
  • URLs:
  • W3C spec level of support
    • generally -> :-)
    • Microsoft, specifically, is interested in making this work in IE

Encrypted Media W3C Spec

David Dorwin :ddorwin

  • Background
    • Published the Encrypted Media Extensions proposal to the W3C
    • Pages pass in keys to encrypted content through JavaScript
    • Generally controversial(!!) on the W3C list
  • Hope to move forward
    • Technical Feedback
    • Began filing bugs on W3C Tracker
    • W3C Task force in the work
  • As of today, Chromium builds include basic support for Encrypted Media spec
    • LayoutTests currently pass on Chromium port
  • Questions
    • Is it generic encrypted content or specific to video/audio.
      • functions exist on the media element; not usable for image content, e.g.
      • this question will be discussed in the WG.
    • There is also the Crypto API, related but not a replacement for this one
  • URLs:

WebAudio API

Jer Noble :jernoble

  • Background on WebAudio API, spec, and implementation
  • GTK is working on implementing this API
  • Mozilla has completely separate approach
    • entirely in JavaScript
    • performance issues
    • extended the MediaStream API to process streams of audio data in WebWorkers

Full Screen

Jer Noble :jernoble

  • Spec has recently been changed in order to create a new, explicit stacking content for full screen'd elements
  • Will be merged in with <dialog>

Media Statistics

Andrew Scherkus :scherkus

  • Only generally useful stat: Dropped frames
  • Topic for Deprecation Session.