Compaq Multimedia Services for OpenVMS Alpha

Compaq Multimedia Services
for OpenVMS Alpha

Run-Time Environment Guide

Order Number: AA-QN8JC-TE


April 2000

This guide contains run-time information for applications that use the Compaq Multimedia Services for OpenVMS Alpha for AlphaStations running the OpenVMS Alpha operating system.

Revision/Update Information: This document supercedes the Multimedia Services OpenVMS Alpha Run-Time Environment Guide, Version 2.0.

Operating System: OpenVMS Alpha Version 7.1-2 or Version 7.2-1 and higher

Software Version: Compaq Multimedia Services for OpenVMS Alpha Version 2.2



Compaq Computer Corporation Houston, Texas


© 2000 Compaq Computer Corporation

COMPAQ, AlphaStation, VAX, VMS, the Compaq logo, and the DIGITAL logo Registered in U.S. Patent and Trademark Office.

Alpha and OpenVMS are trademarks of Compaq Information Technologies Group, L.P.

Microsoft and Windows are trademarks of Microsoft Corporation. X Window System is a trademark of The Open Group.

All other product names mentioned herein may be the trademarks or registered trademarks of their respective companies.

Confidential computer software. Valid license from Compaq or authorized sublicensor required for possession, use, or copying. Consistent with FAR 12.211 and 12.212, Commercial Computer Software, Computer Software Documentation, and Technical Data for Commercial Items are licensed to the U.S. Government under vendor's standard commercial license.

Compaq Computer Corporation shall not be liable for technical or editorial errors or omissions contained herein. The information in this document is subject to change without notice.

The information in this publication is subject to change without notice and is provided "AS IS" WITHOUT WARRANTY OF ANY KIND. THE ENTIRE RISK ARISING OUT OF THE USE OF THIS INFORMATION REMAINS WITH RECIPIENT. IN NO EVENT SHALL COMPAQ BE LIABLE FOR ANY DIRECT, CONSEQUENTIAL, INCIDENTAL, SPECIAL, PUNITIVE, OR OTHER DAMAGES WHATSOEVER (INCLUDING WITHOUT LIMITATION, DAMAGES FOR LOSS OF BUSINESS PROFITS, BUSINESS INTERRUPTION, OR LOSS OF BUSINESS INFORMATION), EVEN IF COMPAQ HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. THE FOREGOING SHALL APPLY REGARDLESS OF THE NEGLIGENCE OR OTHER FAULT OF EITHER PARTY AND REGARDLESS OF WHETHER SUCH LIABILITY SOUNDS IN CONTRACT, NEGLIGENCE, TORT, OR ANY OTHER THEORY OF LEGAL LIABILITY, AND NOTWITHSTANDING ANY FAILURE OF ESSENTIAL PURPOSE OF ANY LIMITED REMEDY.

The limited warranties for Compaq products are exclusively set forth in the documentation accompanying such products. Nothing herein should be construed as constituting a further or additional warranty.

ZK6627

Contents Index


Preface

This document contains information about the run-time environment for Compaq's implementation of the Microsoft multimedia application programming interface (API). The run-time environment assists applications that use multimedia features for AlphaStation workstations running the OpenVMS Alpha operating system.

Intended Audience

This document is intended for multimedia application developers, including Independent Software Vendors (ISVs) and customers running applications that use Compaq Multimedia Services for OpenVMS Alpha. Readers are expected to be familiar with the following:

The release notes are intended for all users of Compaq Multimedia Services for OpenVMS Alpha. The release notes are located in:

SYS$HELP:MMOV-V2_2.RELEASE_NOTES

Document Structure

This document contains the following:

Chapter 1 introduces the Multimedia Services for OpenVMS online sample application programs included in the software kit. These programs show how to use the Multimedia Services for OpenVMS functions. This chapter also contains a pointer to the installed location of these programs and instructions for building them.

Chapter 2 describes the audiodevices application program.

Chapter 3 describes the audioplay application program.

Chapter 4 describes the audiorecord application program.

Chapter 5 describes the audioselectports program.

Chapter 6 describes the DECsound utility program.

Chapter 7 describes the Audio Control utility program.

Chapter 8 describes the Video Odyssey screen saver.

Chapter 9 describes the AlphaVCR utility program.

The Glossary contains terms associated with multimedia that are used throughout the document.

Related Documents

For additional information about OpenVMS products and services, access the following OpenVMS World Wide Web address:


http://www.compaq.com 

Support

If errors occur during product installation, the system displays failure messages. For descriptions of error messages, see the OpenVMS Alpha documentation on system messages, recovery procedures, and software installation.

If an error occurs while Compaq Multimedia Services for OpenVMS Alpha is in use and you believe the error is caused by a problem with the product, contact your Compaq support representative.

Reader's Comments

Compaq welcomes your comments on this manual. Please send comments to either of the following addresses:
Internet openvmsdoc@compaq.com
Mail Compaq Computer Corporation
OSSG Documentation Group, ZKO3-4/U08
110 Spit Brook Rd.
Nashua, NH 03062-2698

How To Order Additional Documentation

Use the following World Wide Web address to order additional documentation:


http://www.compaq.com 

Click Documentation under Quick Links.

If you need help deciding which documentation best meets your needs, call 800-282-6672.

Conventions

The following conventions are used in this manual:

Every use of Multimedia Services for OpenVMS means Compaq Multimedia Services Version 2.2 for OpenVMS Alpha.
Ctrl/ x A sequence such as Ctrl/ x indicates that you must hold down the key labeled Ctrl while you press another key or a pointing device button.
PF1 x A sequence such as PF1 x indicates that you must first press and release the key labeled PF1 and then press and release another key or a pointing device button.
[Return] In examples, a key name enclosed in a box indicates that you press a key on the keyboard. (In text, a key name is not enclosed in a box.)

In the HTML version of this document, this convention appears as brackets, rather than a box.

... A horizontal ellipsis in examples indicates one of the following possibilities:
  • Additional optional arguments in a statement have been omitted.
  • The preceding item or items can be repeated one or more times.
  • Additional parameters, values, or other information can be entered.
.
.
.
A vertical ellipsis indicates the omission of items from a code example or command format; the items are omitted because they are not important to the topic being discussed.
( ) In command format descriptions, parentheses indicate that you must enclose the options in parentheses if you choose more than one.
[ ] In command format descriptions, brackets indicate optional elements. You can choose one, none, or all of the options. (Brackets are not optional, however, in the syntax of a directory name in an OpenVMS file specification or in the syntax of a substring specification in an assignment statement.)
[|] In command format descriptions, vertical bars separating items inside brackets indicate that you choose one, none, or more than one of the options.
{ } In command format descriptions, braces indicate required elements; you must choose one of the options listed.
bold text This text style represents the introduction of a new term or the name of an argument, an attribute, or a reason.
italic text Italic text indicates important information, complete titles of manuals, or variables. Variables include information that varies in system output (Internal error number), in command lines (/PRODUCER= name), and in command parameters in text (where dd represents the predefined code for the device type).
UPPERCASE TEXT Uppercase text indicates a command, the name of a routine, the name of a file, or the abbreviation for a system privilege.
Monospace text Monospace type indicates code examples and interactive screen displays.

In the C programming language, monospace type in text identifies the following elements: keywords, the names of independently compiled external functions and files, syntax summaries, and references to variables or identifiers introduced in an example.

- A hyphen at the end of a command format description, command line, or code line indicates that the command or statement continues on the following line.
numbers All numbers in text are assumed to be decimal unless otherwise noted. Nondecimal radixes---binary, octal, or hexadecimal---are explicitly indicated.


Chapter 1
Introduction to Sample Application Programs

This chapter lists the run-time application programs that show how to use many of the Compaq Multimedia Services for OpenVMS Alpha functions. These programs are shipped with the run-time kit and installed during the software installation procedure in the directory SYS$SYSTEM.

Use help with each program (except Audio Control) to display its associated help message. The help message lists the command line switches that can be used with that program.

In addition, most of these applications use the X Window System services and require that the DISPLAY environment variable be set correctly.

Table 1-1 lists and describes the online sample programs.

Table 1-1 Summary of Run-Time Application Programs
Program Name Description
audiodevices An application program that provides audio device capabilities.
audioplay An application program that plays back an audio file.
audiorecord An application program that records audio to a file.
audioselectports A program that selects input or output ports for audio devices.
DECsound A utility program that serves as a tape recorder utility for recording, editing, and playing back audio messages. This utility is used to play back the sample audio clips (.ddif and .sun files) shipped with the system.
Audio Control A utility program that is used to adjust input and output volumes of audio devices, select ports, and show available formats.
Video Odyssey A screen saver program that plays video clips to protect the monitor from "burn-in."
AlphaVCR A utility program for recording and playing back audio and video data in AVI format. This utility is used to play back the sample audio and video clips (AVI and MPEG files) shipped with the system.

The PCSI kit contains sample data files. The sample .AVI and .MPG files can be played back with using AlphaVCR and Video Odyssey. The .WAV samples can be played back using audioplay and DECsound.


Chapter 2
The audiodevices Program

The audiodevices application program gets audio device capabilities. The program prints out the available audio devices for the Multimedia Services product, the associated device numbers, and the device capabilites for both input and output.

2.1 Audio Device Information

The audiodevices program provides the following information regarding the audio devices you use with the Multimedia Services product:

2.2 Syntax for audiodevices

To invoke audiodevices , create a foreign command. The following example defines the symbol audiodevices as a foreign command.


$ audiodevices :== $SYS$SYSTEM:MMOV$AUDIODEVICES.EXE 

audiodevices uses the following command line options.

[-idevice #]
is the input device number. The default is display all.

[-odevice #]
is the output device number. The default is display all.

[-verbose]
prints various status messages.

[-help]
displays help information.


Chapter 3
The audioplay Program

The audioplay application program plays an audio file using the Multimedia Services product. The file may be in WAVE format or SUN (.au) format. This includes files recorded using the audiorecord and DECsound programs. If the file is not in one of these formats, it will be played as a raw audio file.

The format options that are in the file header will be used to play the file. The user can override any of these using the command line options. If the file is a raw audio file, then the default values will be used.

Pressing Ctrl/C pauses the playback, which can be resumed by pressing Return. Pressing a second Ctrl/C terminates the program; otherwise, the entire file is played.

To determine the device number and formats supported for an audio output device, use the audiodevices program.

3.1 Syntax for audioplay

To invoke audioplay , create a foreign command. The following example defines the symbol audioplay as a foreign command:


$ audioplay :== $SYS$SYSTEM:MMOV$AUDIOPLAY.EXE 

audioplay uses the following command line options:

[-filename filename]
is the audio file name to play. If the file name is "-", input will be taken from stdin (the standard input device). The default is tempfile.wav .

[-odevice #]
is the output device number. The default is the first available device.

[-channels #]
is the number of channels. The channel may be mono (1) or stereo (2). The default is mono (1).

[-bitspersample #]
is the number of bits per sample. The default is 8.

[-rate #]
is the sample rate in Hz. The default is 8000.

[-encoding format]
is an audio encoding format. Valid entries are pcm for PCM format or mulaw for mulaw format. The default is mulaw.

[-numbuffers #]
is the number of buffers to allocate. The default is 4.

[-sizebuffers #]
is the size, in bytes, of each buffer.

If values are entered for [-sizebuffers #] and [-msbuffers #] , the
[-msbuffers #] value is used and the [-sizebuffers #] value is ignored.

By default, the byte size of each buffer is dependent on the value for
[-msbuffers #] .

[-msbuffers #]
is the size, in milliseconds, of each buffer. Unless [-sizebuffers #] overrides this value, the default value is 250 milliseconds.

[-verbose]
prints various status messages while playing the file.

[-help]
displays help information.


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