OpenMAX
Encyclopedia
OpenMAX is a royalty-free, cross-platform set of C-language
programming interfaces that provides abstractions for routines especially useful for audio, video, and still images. It's intended for devices that process large amounts of multimedia data in predictable ways.
OpenMAX provides three layers of interfaces: Application Layer (AL), Integration Layer (IL) and Development Layer (DL). OpenMAX is managed by the non-profit
technology consortium
Khronos Group
.
.
OpenMAX IL is the interface between media framework such as DirectShow
or GStreamer
and a set of multimedia components (such as an audio or video codec
s). It allows companies that build platforms (for example an MP3 player) to easily change components like MP3 decoders and Equalizer effects and buy components for their platform from different vendors.
OpenMAX DL is the interface between physical hardware, such as DSP
chips and CPUs
, and software, like video codec
s and 3D engines. It allows companies to easily integrate new hardware that supports OpenMAX DL without reoptimizing their low level software.
, as well as interfaces
on those objects, to control and configure them. The OpenMAX AL API is divided into two profiles: Media Player and Media Player/Recorder. A platform can be compliant to one or both of these profiles by providing all features included in a profile.
It is an application-level, C-language
, multimedia API designed for resource-constrained devices. The OpenMAX AL API design puts particular emphasis on ensuring the API is suitable for mobile embedded devices
- including basic mobile phones, smart “feature” phones, PDAs and mobile digital music players. Nevertheless, this does not preclude its applicability to other sophisticated media playback and recording devices.
The OpenMAX AL API design devotes particular attention to application-developer friendliness. Its status as an open cross-platform API enables developers to port the same source across multiple devices with minimal effort. Thus OpenMAX AL provides a stable base for application development.
Comparison with OpenSL ES
OpenSL ES
is another Khronos Group API providing a Sound Library for Embedded Systems. OpenSL ES
and OpenMAX AL share the same common architecture and have a few common features:
. In the OpenMAX IL, components represent individual blocks of functionality. Components can be sources, sinks, codecs, filters, splitters, mixers, or any other data operator. Depending on the implementation, a component could possibly represent a piece of hardware, a software codec, another processor, or a combination thereof.
The interface abstracts the hardware and software architecture in the system. The OpenMAX IL API allows the user to load, control, connect, and unload the individual components. This flexible core architecture allows the Integration Layer to easily implement almost any media use case and mesh with existing graph-based media frameworks. The key focus of the OpenMAX IL API is portability of media components
The OpenMAX IL API design devotes particular attention to use case flexibility and optimized data transfers between components.
Open source OpenMAX IL implementations are available,
s and other integrated media processing engines. The functional scope of the OpenMAX DL interface spans several domains including Signal processing
and Image processing
, audio coding
, image coding
, and video coding
.
OpenMAX DL is split into five application domains:
OpenMAX DL is, among other companies, openmax_armlibraries implemented by ARM and ANSI C
sample code can be downloaded from their webpage.
The OpenMAX API is supported by the PlayStation 3
console.
on July 6th, 2004. Promoting members (2008-01-17) are AMD, Apple, ARM
, Creative
, Dell Inc, Ericsson
, Freescale, Imagination Technologies Group plc
, Intel, IBM
, Motorola
, Nokia
, Nvidia Corporation, Samsung Electronics Co. Ltd
, SK Telecom
, Sony Computer Entertainment Inc
, Sun Microsystems Inc
and Texas Instruments
.
OpenMAX API documentation is publicly available on the Khronos website.
C (programming language)
C is a general-purpose computer programming language developed between 1969 and 1973 by Dennis Ritchie at the Bell Telephone Laboratories for use with the Unix operating system....
programming interfaces that provides abstractions for routines especially useful for audio, video, and still images. It's intended for devices that process large amounts of multimedia data in predictable ways.
OpenMAX provides three layers of interfaces: Application Layer (AL), Integration Layer (IL) and Development Layer (DL). OpenMAX is managed by the non-profit
Non-profit organization
Nonprofit organization is neither a legal nor technical definition but generally refers to an organization that uses surplus revenues to achieve its goals, rather than distributing them as profit or dividends...
technology consortium
Consortium
A consortium is an association of two or more individuals, companies, organizations or governments with the objective of participating in a common activity or pooling their resources for achieving a common goal....
Khronos Group
Khronos Group
The Khronos Group is a not-for-profit member-funded industry consortium based in Beaverton, Oregon, focused on the creation of open standard, royalty-free APIs to enable the authoring and accelerated playback of dynamic media on a wide variety of platforms and devices...
.
OpenMAX layers
OpenMAX AL is the interface between multimedia applications, such as a media player, and the platform media framework. It allows companies that develop applications to easily migrate their applications to different platforms (customers) that support the OpenMAX AL APIApplication programming interface
An application programming interface is a source code based specification intended to be used as an interface by software components to communicate with each other...
.
OpenMAX IL is the interface between media framework such as DirectShow
DirectShow
DirectShow , codename Quartz, is a multimedia framework and API produced by Microsoft for software developers to perform various operations with media files or streams. It is the replacement for Microsoft's earlier Video for Windows technology...
or GStreamer
GStreamer
GStreamer is a pipeline-based multimedia framework written in the C programming language with the type system based on GObject.GStreamer allows a programmer to create a variety of media-handling components, including simple audio playback, audio and video playback, recording, streaming and editing...
and a set of multimedia components (such as an audio or video codec
Codec
A codec is a device or computer program capable of encoding or decoding a digital data stream or signal. The word codec is a portmanteau of "compressor-decompressor" or, more commonly, "coder-decoder"...
s). It allows companies that build platforms (for example an MP3 player) to easily change components like MP3 decoders and Equalizer effects and buy components for their platform from different vendors.
OpenMAX DL is the interface between physical hardware, such as DSP
Digital signal processor
A digital signal processor is a specialized microprocessor with an architecture optimized for the fast operational needs of digital signal processing.-Typical characteristics:...
chips and CPUs
Central processing unit
The central processing unit is the portion of a computer system that carries out the instructions of a computer program, to perform the basic arithmetical, logical, and input/output operations of the system. The CPU plays a role somewhat analogous to the brain in the computer. The term has been in...
, and software, like video codec
Codec
A codec is a device or computer program capable of encoding or decoding a digital data stream or signal. The word codec is a portmanteau of "compressor-decompressor" or, more commonly, "coder-decoder"...
s and 3D engines. It allows companies to easily integrate new hardware that supports OpenMAX DL without reoptimizing their low level software.
OpenMAX AL (Application Layer)
OpenMAX AL accommodates common multimedia application use cases by standardizing a set of representative objectsObject (computer science)
In computer science, an object is any entity that can be manipulated by the commands of a programming language, such as a value, variable, function, or data structure...
, as well as interfaces
Interface (computer science)
In the field of computer science, an interface is a tool and concept that refers to a point of interaction between components, and is applicable at the level of both hardware and software...
on those objects, to control and configure them. The OpenMAX AL API is divided into two profiles: Media Player and Media Player/Recorder. A platform can be compliant to one or both of these profiles by providing all features included in a profile.
It is an application-level, C-language
C (programming language)
C is a general-purpose computer programming language developed between 1969 and 1973 by Dennis Ritchie at the Bell Telephone Laboratories for use with the Unix operating system....
, multimedia API designed for resource-constrained devices. The OpenMAX AL API design puts particular emphasis on ensuring the API is suitable for mobile embedded devices
Embedded system
An embedded system is a computer system designed for specific control functions within a larger system. often with real-time computing constraints. It is embedded as part of a complete device often including hardware and mechanical parts. By contrast, a general-purpose computer, such as a personal...
- including basic mobile phones, smart “feature” phones, PDAs and mobile digital music players. Nevertheless, this does not preclude its applicability to other sophisticated media playback and recording devices.
The OpenMAX AL API design devotes particular attention to application-developer friendliness. Its status as an open cross-platform API enables developers to port the same source across multiple devices with minimal effort. Thus OpenMAX AL provides a stable base for application development.
Features
OpenMAX AL features include:- Video playback and recording
- Audio playback and recording
- Image capture (camera) and display
- Camera controls
- Radio and RDSRadio Data SystemRadio Data System, or RDS, is a communications protocol standard for embedding small amounts of digital information in conventional FM radio broadcasts. RDS standardises several types of information transmitted, including time, station identification and programme information.Radio Broadcast Data...
- Basic MIDI playback
- Metadata extraction and insertion
Specification versions
- OpenMAX AL 1.0 Provisional Specification - a provisional version, dated 2007-09-02, to facilitate feedback from the community before the final 1.0 release.
- OpenMAX AL 1.0 Specification - dated 2009-06-23
- OpenMAX AL 1.0.1 Specification - dated 2010-03-12
- OpenMAX AL 1.1 Specification - dated 2011-01-18
Implementations
- An open source implementation of AL is available at LIM OpenMAX.
- Android 4.0 exposes OpenMAX AL 1.0.1 as part of their NDK.
Comparison with OpenSL ESOpenSL ESOpenSL ES is a royalty-free,cross-platform, hardware-accelerated,C-language audio API for 2D and 3D audio.It provides access to features such as 3D positional audio and MIDI playback....
OpenSL ESOpenSL ES
OpenSL ES is a royalty-free,cross-platform, hardware-accelerated,C-language audio API for 2D and 3D audio.It provides access to features such as 3D positional audio and MIDI playback....
is another Khronos Group API providing a Sound Library for Embedded Systems. OpenSL ES
OpenSL ES
OpenSL ES is a royalty-free,cross-platform, hardware-accelerated,C-language audio API for 2D and 3D audio.It provides access to features such as 3D positional audio and MIDI playback....
and OpenMAX AL share the same common architecture and have a few common features:
- Audio playback and recording
- Basic MIDI playback
- Metadata extraction
OpenMAX IL (Integration Layer)
The OpenMAX IL API strives to give media components portability across an array of platforms using the C-languageC (programming language)
C is a general-purpose computer programming language developed between 1969 and 1973 by Dennis Ritchie at the Bell Telephone Laboratories for use with the Unix operating system....
. In the OpenMAX IL, components represent individual blocks of functionality. Components can be sources, sinks, codecs, filters, splitters, mixers, or any other data operator. Depending on the implementation, a component could possibly represent a piece of hardware, a software codec, another processor, or a combination thereof.
The interface abstracts the hardware and software architecture in the system. The OpenMAX IL API allows the user to load, control, connect, and unload the individual components. This flexible core architecture allows the Integration Layer to easily implement almost any media use case and mesh with existing graph-based media frameworks. The key focus of the OpenMAX IL API is portability of media components
The OpenMAX IL API design devotes particular attention to use case flexibility and optimized data transfers between components.
Open source OpenMAX IL implementations are available,
- Bellagio, is maintained by STMicroelectronics.
- LIM OpenMAX, an implementation that has both AL and IL.
OpenMAX DL (Development Layer)
The OpenMAX DL API defines a set of low-level multimedia kernels or media processing building blocks. The building blocks might be used to accelerate traditional computational hotspots within standardized media codecCodec
A codec is a device or computer program capable of encoding or decoding a digital data stream or signal. The word codec is a portmanteau of "compressor-decompressor" or, more commonly, "coder-decoder"...
s and other integrated media processing engines. The functional scope of the OpenMAX DL interface spans several domains including Signal processing
Signal processing
Signal processing is an area of systems engineering, electrical engineering and applied mathematics that deals with operations on or analysis of signals, in either discrete or continuous time...
and Image processing
Image processing
In electrical engineering and computer science, image processing is any form of signal processing for which the input is an image, such as a photograph or video frame; the output of image processing may be either an image or, a set of characteristics or parameters related to the image...
, audio coding
Audio codec
All codecs are devices or computer programs capable of coding or decoding a digital data stream or signal.The term audio codec has two meanings depending on the context:...
, image coding
Image compression
The objective of image compression is to reduce irrelevance and redundancy of the image data in order to be able to store or transmit data in an efficient form.- Lossy and lossless compression :...
, and video coding
Video codec
A video codec is a device or software that enables video compression and/or decompression for digital video. The compression usually employs lossy data compression. Historically, video was stored as an analog signal on magnetic tape...
.
OpenMAX DL is split into five application domains:
- AC - Audio Codecs (MP3 decoder and AAC decoder components)
- IC - Image Codecs (JPEG components)
- IP - Image Processing (Generic image processing functions)
- SP - Signal Processing (Generic audio processing functions)
- VC - Video Codecs (H264 and MP4 components)
OpenMAX DL is, among other companies, openmax_armlibraries implemented by ARM and ANSI C
C (programming language)
C is a general-purpose computer programming language developed between 1969 and 1973 by Dennis Ritchie at the Bell Telephone Laboratories for use with the Unix operating system....
sample code can be downloaded from their webpage.
The OpenMAX API is supported by the PlayStation 3
PlayStation 3
The is the third home video game console produced by Sony Computer Entertainment and the successor to the PlayStation 2 as part of the PlayStation series. The PlayStation 3 competes with Microsoft's Xbox 360 and Nintendo's Wii as part of the seventh generation of video game consoles...
console.
OpenMAX Working Group
The OpenMAX Working Group was founded alongside sister project OpenVGOpenVG
OpenVG is a standard API designed for hardware-accelerated 2D vector graphics. It is aimed primarily at mobile phones, media and gaming consoles such as the PlayStation 3, and other consumer electronic devices. It will help manufacturers create flashier user interfaces that are less dependent on...
on July 6th, 2004. Promoting members (2008-01-17) are AMD, Apple, ARM
ARM Holdings
ARM Holdings plc is a British multinational semiconductor and software company headquartered in Cambridge. Its largest business is in processors, although it also designs, licenses and sells software development tools under the RealView and KEIL brands, systems and platforms, system-on-a-chip...
, Creative
Creative Technology
Creative Technology Ltd. is a Singapore-based global company headquartered in Jurong East, Singapore. The principal activities of the company and its subsidiaries consist of the design, manufacture and distribution of digitized sound and video boards, computers and related multimedia, and personal...
, Dell Inc, Ericsson
Ericsson
Ericsson , one of Sweden's largest companies, is a provider of telecommunication and data communication systems, and related services, covering a range of technologies, including especially mobile networks...
, Freescale, Imagination Technologies Group plc
Imagination Technologies
Imagination Technologies Group plc is a British-based maker of a mobile graphics and microprocessor chip technology primarily known for its PowerVR graphics and Pure DAB radio divisions...
, Intel, IBM
IBM
International Business Machines Corporation or IBM is an American multinational technology and consulting corporation headquartered in Armonk, New York, United States. IBM manufactures and sells computer hardware and software, and it offers infrastructure, hosting and consulting services in areas...
, Motorola
Motorola
Motorola, Inc. was an American multinational telecommunications company based in Schaumburg, Illinois, which was eventually divided into two independent public companies, Motorola Mobility and Motorola Solutions on January 4, 2011, after losing $4.3 billion from 2007 to 2009...
, Nokia
Nokia
Nokia Corporation is a Finnish multinational communications corporation that is headquartered in Keilaniemi, Espoo, a city neighbouring Finland's capital Helsinki...
, Nvidia Corporation, Samsung Electronics Co. Ltd
Samsung Electronics
Samsung Electronics is a South Korean multinational electronics and information technology company headquartered in Samsung Town, Seoul...
, SK Telecom
SK Telecom
SK Telecom Co., Ltd. or Sunkyoung Telecom is a South Korean wireless telecommunications operator, controlled by the SK Group, one of the country's largest chaebol. As a part of SK Group, SK stands for Sun Kyung.SK Telecom is a provider of mobile service in Korea, with 50.5% of the market share as...
, Sony Computer Entertainment Inc
Sony Computer Entertainment
Sony Computer Entertainment, Inc. is a major video game company specializing in a variety of areas in the video game industry, and is a wholly owned subsidiary and part of the Consumer Products & Services Group of Sony...
, Sun Microsystems Inc
Sun Microsystems
Sun Microsystems, Inc. was a company that sold :computers, computer components, :computer software, and :information technology services. Sun was founded on February 24, 1982...
and Texas Instruments
Texas Instruments
Texas Instruments Inc. , widely known as TI, is an American company based in Dallas, Texas, United States, which develops and commercializes semiconductor and computer technology...
.
OpenMAX API documentation is publicly available on the Khronos website.
External links
- Khronos Group — OpenMAX Overview and API specifications
- Khronos Group — Public API Registry
- Khronos Group — OpenMAX AL 1.1 Specification
- Khronos Group — OpenMAX IL 1.1.2 Specification
- Khronos Group — OpenMAX DL 1.0.2 Specification
- Public forums
- Khronos Group — Press Releases — OpenMAX
- Mentor Graphics - Nucleus MMF Leverages OpenMAX IL
- Mentor Graphics - Press Release, Mentor Achieves Industry-First OpenMAX Conformance for Nuclues OS Multimedia Framework