NAME

mms − Multimedia Services for Digital UNIX. 

SYNOPSIS

Multimedia Services for Digital UNIX is Digital’s standard application programming interface (API) to multimedia functionality on Alpha workstations running the Digital UNIX operating system. It is a set of software services and tools for developing applications that use multimedia features on these systems. 

DESCRIPTION

Multimedia Services for Digital UNIX provides software support for both hardware and software multimedia devices.  For descriptions of devices supported by this product, please type:

$ man -k ’Device for MMS’

Multimedia Services for Digital UNIX also provides support for standard IBM[R] and Microsoft Resource Interchange File Format (RIFF) file I/O, which is independent of any device. See the Multimedia Services for Digital UNIX Programmer’s Guide for more information on multimedia hardware support. 

Multimedia Services for Digital UNIX has a client/server architecture that uses shared memory transport to communicate between the client applications and the server levels controlling the multimedia hardware.  The server can thus accept requests from various client applications that run on the same machine.  The multimedia services include the following:

o  Waveform audio recording and playback

An application uses waveform audio services to manage the recording and playback of waveform audio. The primary waveform audio functions give an application the ability to record audio (encode audio signals and capture digitized audio in buffers) and to play audio (generate output audio waveforms from digitized audio contained in buffers). 

The waveform audio services also include supporting functions that allow an application to query device capabilities and to open, close, and configure devices. 

o Video capture and playback

An application uses the low-level video services for video capture and playback.  The video capture services allow an application to capture incoming video signals, either single frames or real-time streams, into memory buffers. 

The video capture and playback services also include supporting functions that allow an application to query device capabilities and to open, close, and configure devices. 

o Video compression and decompression

An application uses video compression and decompression services to compress or decompress video data.  These services provide access to multimedia support for JPEG, Intel Indeo (TM), and H.261 compression and decompression and for dithering. 

The video compression and decompression services also include functions for managing devices and for controlling the compression parameters that affect the quality of compressed video image data. 

o Multimedia file I/O

An application uses file I/O services in conjunction with the other multimedia functions to create, read, and write disk files that store audio and video data.  The files are in RIFF format and include the Waveform Audio (WAVE) file format and the Audio/Video Interleaved (AVI) file format. 

STARTING UP

The server process, mmeserver, must be running before executing any application program that uses the multimedia API. The server process is located at /usr/bin/mmeserver. It is recommended that the server process be started as root at boot time. 

To start the server process, log in as a superuser (login name root) and enter the following command:

# /sbin/init.d/mmeserver start

To stop the server process, enter the following command:

# /sbin/init.d/mmeserver stop

Before starting a server, stop any previously running server. 

See the mmeserver(1mms) man for more details. 

SUBSETS

Multimedia Services for Digital UNIX is comprised of the following available subsets.  Note: Not all subsets are shipped with distribution packages, so please check your distribution for availability.  Availability codes are as follows:
SPLSoftware Product Library CD
UNIXDigital UNIX Operating System CD
FISFactory Installed. Note that not all subsets marked as FIS are distributed with every FIS package. 
ALLAll of the above

DIAGNOSTICS

If you receive errors from the either the server or client side library, please forward all information you can gather (including stack traces) via the SPR system. 

SEE ALSO

mmeserver(1mms), alphavcr(1mms), audiocontrol(1mms), decsound(1mms), videoodessey(1mms), system.ini(4mms), mmsdev(1mms), and the Multimedia Services for Digital UNIX Application User’s Guide.