Openmax AL, Opensl ES Native Multimedia in Android

OpenMAX AL, OpenSL ES Native Multimedia in Android

Erik Noreke Chair of OpenMAX AL and OpenSL ES Working Groups

Khronos APIs Open Source Framework • Conformance Tests • Free to change • Portable • Every implementation unique • IP Protection • GPL license • Profiles & Components • Plugins • Predictable set of functionality • Functionality dependent on implementation

Application Access Layer

© Copyright Khronos Group, 2011 - Page 3 The Need for Application Access • Hardware and low level access is powerful but complex - More power than most application developers require • Most application developers just want to playback and record media - Specifying where the content comes from and is rendered to - Manipulate a few playback controls - Have simple configurability

© Copyright Khronos Group, 2011 - Page 4 The Need for Application Access • That are what OpenMAX AL and OpenSL ES provide… - Simple high-level multimedia APIs for playback and recording use cases - With hardware acceleration capabilities built in • …With Cross-platform portability - No need to rewrite an application for every platform

• Media playback and recording - Playback and recording of everything from video files to radio to camera input • Full range of video effects and controls – including playback rate, post processing, and image manipulation - Apply advanced effects to captured images and video before sending to friends

• OpenMAX AL gives easy access to streaming media - Allowing time to be spent on developing applications, not using frameworks • Designed as a complete set of multimedia functionality - Unlike any other streaming media API

• Full range of effects and controls, including advanced 3D effects such as Doppler and virtualization - Experience rich, enhanced sound from locations other than the handset, even moving, for the ultimate multimedia experience • Create theater quality audio experience - In a mobile device!

• Full 3D audio functionality enhances any gaming experience - Perfect companion to OpenGL ES • Designed for implementation by either a hardware or software solution - Take full advantage of system capabilities

• Simplified object-oriented streaming media - Built to enable common use cases - But also has access to advanced functionality • Media Objects enable PLAY and RECORD of content - Media Objects input and output to Devices - Perform some operation on an input and emit the result as output • Objects have control interfaces - Play, Record, Seek, Rate

Media Input Audio Mix

Camera (AL) Display Window (AL)

URI DSrc Player Object DSnk URI

Memory Memory

Content pipe Content pipe

Video 3D Audio playback Audio Video Playback recording Audio Effects Radio and RDS Audio Advanced Recording Camera MIDI

Basic Image capture Buffer MIDI & display queues

• Functionality divided into basic groups - Most common groupings • Profiles reduce fragmentation - Not all devices support all functionality - Only support the profiles you need • Applications can query available profiles - To adapt to the current device - Facilitates porting of applications

• Profiles can be combined - To best suit any product • Optional features - Some features are optional in all profiles - APIs are consistent when feature is available

© Copyright Khronos Group, 2011 - Page 14 OpenSL ES and OpenMAX AL • Independent - But designed to work together - No dependency between the APIs – either one can exist by itself • Compatible - Working groups collaborated to make sure the APIs work together well

© Copyright Khronos Group, 2011 - Page 15 OpenSL ES and OpenMAX AL • Consistent - Identical API architecture - Identical APIs for same functionality • Distinct - OpenMAX AL represents basic multimedia functionality (audio, video, and image) - OpenSL ES represents advanced audio functionality

Audio stream to DSP 3D Audio Rendering

Multimedia Application Processing on CPU

Video stream to GPU

OpenGL ES EGLStream GL_TEXURE_EXTERN OpenGL ES EGLSurface AL_OES texture

Much more flexibility than just “show a video”

Mobile 3D

• Better control of fuctionality and timing • Access to hardware acceleration • Multimedia is the primary reason for the NDK

• Increases application complexity • Requires compilation for each platform family - ARMv5TE - ARMv7-A - x86 instructions

• Earlier internal APIs not stable enough…

• Avoid fragmentation • Well tested and documented • Focus on functionality - Not on implementation • Access to hardware acceleration

• OpenGL ES 2.0 • EGL 1.4 • OpenSL ES 1.0.1 - Partial implementation Mobile 3D - Almost complete Phone + Music profiles - Buffer queues from 1.1 as Android extension - Google version compliant as far as implemented - Other vendors offer fully compliant solution

Graphics Context Advanced Audio Management

© Copyright Khronos Group, 2011 - Page 21 Ice Cream Sandwich – Android 4.0 • Same OS for both phones and tablets • Better multitasking • Better support for hardware accelerated graphics • DRM • Partial OpenMAX AL 1.0.1 implementation - Streaming use-case only - Does not interoperate with OpenSL ES

Streaming Media

• Android uses OpenMAX IL in their Multimedia framework - Codecs only - No graph building • Main Multimedia framework is still Stagefright - Introduced in Éclair • Allows for both software implemented and hardware accelerated codecs • Not part of NDK - Not intended to be accessible from applications

• More Devices - TVs? - Netbooks? - Chrome OS?

• What does the future hold? - Compliant OpenSL ES? - Better OpenMAX AL support? - OpenMAX AL EGL Stream Extension? - Support for OpenCL? - Content Pipes?