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-
- ΓòÉΓòÉΓòÉ 1. Using the Online Reference ΓòÉΓòÉΓòÉ
-
- Before you begin to use this reference, it would be helpful to understand how
- you can:
-
- o Expand the Contents to see all available topics
- o Obtain additional information for a highlighted word or phrase
- o Use action bar choices.
-
- How To Use the Contents
-
- When the Contents window first appears, some topics have a plus (+) sign beside
- them. The plus sign indicates that additional topics are available.
-
- To expand the Contents if you are using a mouse, select the plus sign (+). If
- you are using a keyboard, use the Up or Down Arrow key to highlight the topic,
- and press the plus key (+).
-
- To view a topic, double-click on the topic (or press the Up or Down Arrow key
- to highlight the topic, and then press Enter).
-
- How To Obtain Additional Information
-
- After you select a topic, the information for that topic appears in a window.
- Highlighted words or phrases indicate that additional information is available.
- You will notice that certain words in the following paragraph are highlighted
- in green letters, or in white letters on a black background. These are called
- hypertext terms. If you are using a mouse, double-click on the highlighted
- word. If you are using a keyboard, press the Tab key to move to the
- highlighted word, and then press the Enter key. Additional information will
- appear in a window.
-
- How To Use Action Bar Choices
-
- Several choices are available for managing information presented in the The
- OS/2 Multimedia Advantage. There are three pull-down menus on the action bar:
- the Services menu, the Options menu, and the Help menu.
-
- The actions that are selectable from the Services menu operate on the active
- window currently displayed on the screen. These actions include the following:
-
- Bookmark
- Sets a place holder so you can retrieve information of interest to
- you.
-
- Search
- Finds occurrences of a word or phrase in the current topic, selected
- topics, or all topics.
-
- Print
- Prints one or more topics. You can also print a set of topics by
- first marking the topics in the Contents list.
-
- Copy
- Copies a topic you are viewing to a file you can edit.
-
- Options
- Changes the way the Contents is displayed.
-
-
- ΓòÉΓòÉΓòÉ 2. Characteristics and Requirements of Multimedia ΓòÉΓòÉΓòÉ
-
- With the release of OS/2 2.1, Multimedia Presentation Manager/2 (MMPM/2) is
- packaged with OS/2. The following sections describe why OS/2 and MMPM/2
- combine to create an ideal multimedia platform.
-
-
- ΓòÉΓòÉΓòÉ 2.1. Multimedia Operating System ΓòÉΓòÉΓòÉ
-
- The effective use of sound, image, animation, text, and video typically impose
- requirements that are well beyond anything ever imagined in the design of
- personal computer operating systems. Unlike text editors or other typical
- applications that can gracefully wait until another application has yielded use
- of the processor, multimedia applications often cannot tolerate processing
- delays without significant loss in the quality of the presentation. An example
- of this is when an application cannot send digitized video to the screen at the
- required rate.
-
- One approach to solving the problems caused by processing delays would be to
- let a multimedia application retain exclusive use of the processor. But this
- approach would conflict with another multimedia requirement, namely
- responsiveness. A multimedia operating system must provide superior and
- seemingly dedicated throughput while at the same time remain responsive to
- interactive applications. This can only be accomplished by an operating system
- that maximizes allocation of its resources using such key technologies as
- preemptive multitasking, priority scheduling, overlapped I/O, and demand-paged
- virtual memory. Operating System/2* ( OS/2*) 2.1 uses these technologies and
- delivers an ideal multimedia environment.
-
-
- ΓòÉΓòÉΓòÉ 2.2. Advanced User Interface ΓòÉΓòÉΓòÉ
-
- An advanced object-oriented human interface complements the technological
- powerhouse provided by the operating system kernel. OS/2 2.1 implements the
- workplace model of the Common User Access* (CUA*) 1991 specification, referred
- to as the Workplace Shell*. Productivity gains resulting from increased
- usability are significant not only for the end user, but also for the software
- developer. OS/2 2.1 provides several advanced user interface controls including
- notebooks, sliders, and containers.
-
-
- ΓòÉΓòÉΓòÉ 2.2.1. Notebooks ΓòÉΓòÉΓòÉ
-
- Notebooks resemble their physical counterparts in that they are organized into
- sections divided by tabs. The user can leaf through the notebook a page at a
- time, or use the tabs to move quickly from section to section. The tabs can
- contain text or graphics to communicate their meaning.
-
- The Multimedia Setup application uses the OS/2 2.1 notebook control to provide
- users with a convenient method for maintaining the settings for multimedia
- devices.
-
- Notebook Features
-
- o Notebook metaphor.
- o Central and familiar place for device control.
- o Quick access to device settings.
-
- Using the metaphor of a notebook, all multimedia device settings are controlled
- from a central and familiar place, greatly enhancing the usability of the
- system.
-
- While multimedia technology and hardware devices can be complicated, the use
- and configuration of these devices need be no different than any other device
- in OS/2 2.1.
-
-
- ΓòÉΓòÉΓòÉ 2.2.2. Sliders ΓòÉΓòÉΓòÉ
-
- Sliders are similar to scroll bars in that they provide a simple mechanism that
- enables the user to quickly move across a wide range of values.
-
- The Media Player for Digital Video uses sliders to control the volume and media
- position of movie files.
-
- Slider Features
-
- o Easy to use.
- o Move quickly across a range of values.
- o Wide variety of uses.
-
- The subtle difference between a scroll bar and a slider is illustrated by the
- use of a scroll bar to move the viewport of a text editor to a specific
- location within a document, whereas a slider is used to set the value of a
- particular item.
-
-
- ΓòÉΓòÉΓòÉ 2.2.3. Containers ΓòÉΓòÉΓòÉ
-
- Containers arecontrolsthatcancontainothersystemobjects
- .AgoodexampleofacontainerarethefoldersusedintheWorkplaceShell
- .TheMultimediafoldershownbelowcontainsavarietyofmultimediaapplications .
-
- The use of containers as a graphical equivalent of a conventional file system
- directory is just one use for containers. Containers can be used for any
- abstract collection of objects.
-
- Container Features
-
- o Workplace Shell folders.
- o Any collection of system objects.
- o Easy way to manage program and data objects.
-
-
- ΓòÉΓòÉΓòÉ 2.2.4. Additional Multimedia Controls ΓòÉΓòÉΓòÉ
-
- MMPM/2 defines several Presentation Manager window classes that lend a
- sophisticated multimedia quality to a user interface: graphical button,
- circular slider, and secondary window. These controls are implemented in the
- MMPM/2 Volume Control application shown below.
-
- The Volume Control application provides system-wide control of the master
- volume level of all active multimedia devices, allowing the user a single point
- of interaction for volume control.
-
- The dial that adjusts the volume is a circular slider. The mute button, shown
- with a speaker graphic that is grayed when the button is pressed, is a
- two-state graphical button. And the dialog window of the application is a
- secondary window.
-
- Graphical button controls allow replacement of conventional text-faced buttons
- with either two-state or animated graphics. Standard text-faced buttons can be
- replaced by graphical buttons without any change in source code. Only the
- dialog template needs to be modified. Implementing two-state and animated
- buttons requires a minimal investment in development time that is equivalent to
- implementation using the standard push button control.
-
- Circular slider controls present an interesting alternative to the Workplace
- Shell slider control in that the physical appearance of the control is very
- similar to the controls on actual multimedia hardware. This resemblance allows
- end users to transfer knowledge acquired from using real devices to multimedia
- applications. The circular slider can also provide a savings in screen real
- estate compared to a conventional slider. The complexity of developing
- software using a circular slider is equivalent to using a standard slider or
- scroll bar.
-
- Secondary window controls represent a significant savings in development
- expense, because all application windows can be developed using a dialog
- template, thus eliminating the need to create, position, and size windows and
- controls. All of the MMPM/2 system applications utilize secondary windows. If
- the window is sized smaller than the actual dialog template, scroll bars can be
- automatically enabled to allow access to the entire dialog.
-
- For more information on the advanced multimedia controls provided by MMPM/2,
- see the MMPM/2 Application Programming Guide or the MMPM/2 Programming
- Reference. For information on design concepts to be considered when designing a
- CUA multimedia interface that is consistent within a particular application,
- and across other products, see CUA Guide to Multimedia User Interface Design.
-
-
- ΓòÉΓòÉΓòÉ 2.2.5. System Sounds ΓòÉΓòÉΓòÉ
-
- A new feature of MMPM/2 allows the association of system events with digital
- audio sound files or OS/2 tune files. Support for system sounds is provided by
- an extension to the OS/2 Sound object.
-
- System sounds transform the OS/2 desktop into a multimedia-enabled workplace,
- where audio cues alert and inform the user of activities on the system. A set
- of system sounds is included and already associated with system events. The
- Sound object allows users to make different associations using the sounds
- supplied by MMPM/2. They also can create their own sounds or use sounds
- supplied by other vendors.
-
- OS/2 System Sounds Events
-
- o Information message
- o Warning message
- o Error message
- o Opening a window
- o Closing a window
- o Picking up an object
- o Dropping an object
- o System startup
- o System shutdown
- o Shredding an object
- o Alarm clock ringing
- o Printer error message
- o Desktop lockup
-
- The Sound page has a play button for testing a sound file before it is
- associated with a system event. It also has a volume control for setting the
- volume level of the sound.
-
- MMPM/2 also provides support for playing and recording sound files from an OS/2
- command file. Playing a sound file from a command file is useful for alerting
- the user when a location in a command file is reached that requires the user to
- do something. This support is implemented in the PLAY.CMD and RECORD.CMD files,
- located in the \MMOS2 directory. The REXX multimedia function used in these
- files is described in the online publication Controlling Multimedia Devices
- with REXX.
-
-
- ΓòÉΓòÉΓòÉ 3. Multimedia Presentation Manager/2 Overview ΓòÉΓòÉΓòÉ
-
- The following sections describe the MMPM/2 applications and programming
- interfaces that are included as part of OS/2.1. Note that MMPM/2 is installed
- separately. This information is intended for individuals such as technical
- advisors, as well as designers and developers of application and subsystem
- software.
-
-
- ΓòÉΓòÉΓòÉ 3.1. Multimedia Applications ΓòÉΓòÉΓòÉ
-
- MMPM/2 provides an exciting array of multimedia applications that includes a
- movie player, a powerful waveform editor, and a super CD player for compact
- disc audio.
-
-
- ΓòÉΓòÉΓòÉ 3.1.1. Digital Video ΓòÉΓòÉΓòÉ
-
- A spectacular new feature of MMPM/2 is the addition of software motion video.
- High-resolution digital movies can now be viewed on your desktop without any
- additional hardware requirement. With the addition of an audio adapter, you
- can enjoy a fully synchronized audio track in addition to the video.
-
- Unlike other systems, MMPM/2 brings you a standard resolution of 320x240 at 15
- frames per second when using the Ultimotion* compression algorithm. This is
- fully four times the resolution of typical software-only video solutions.
-
- Ultimotion creates a digital video data stream that is software scalable at
- playback time to whatever platform is being used. The amount of scalability
- depends on the amount of data put into the video at the time of its creation,
- and the processing capabilities of the playback system. Depending on the
- performance of your computer, Ultimotion can yield up to 30 frames per second
- or resolutions up to 640x480. Ultimotion excels at both 256 and 65,000 color
- depths, providing clear images and data transfer rates within standard CD-ROM
- capabilities (150 kilobytes per second).
-
- Digital Video Features
-
- o No unique hardware required.
- o Software scalable to playback system.
- o Standard resolution of 320x240, 15 fps.
- o Up to 640x480 resolution or 30 fps.
- o Clear images with 256 and 65,000 color depths.
-
- The Indeo** compression algorithm is also supported, giving you true
- cross-platform support for movies and demonstrating the ability of MMPM/2 to
- incorporate new compression algorithms as they become available.
-
- The digital video media player can be used to play movies in a standard movable
- and sizable window. The digital video media driver described in "Digital Video
- Device" can be used by other applications to present video in an
- application-specific window.
-
- Regardless of how you use video, the powerful underlying features of OS/2 2.1
- make software-decompressed video a reality on your desktop today.
-
-
- ΓòÉΓòÉΓòÉ 3.1.2. Digital Audio ΓòÉΓòÉΓòÉ
-
- The Digital Audio application combines the function of a simple player/recorder
- with that of a powerful waveform editor.
-
- Editing operations are done using a graphical representation of a sound file in
- the Edit window.
-
- As you listen to the sound file play, you can watch the cursor move through the
- sound graph. This process enables you to associate the sounds you hear with the
- variations you see in the graph. You can then determine the area you want to
- edit.
-
- Editing of the sound graph is done by marking an area, similar to the way you
- mark text in a text editor. After you mark an area of sound, you can play the
- marked area to ensure it is the sound you want to edit. A variety of editing
- commands enable you to:
-
- o Cut or copy the marked sound to the system clipboard.
- o Paste the sound from the clipboard into a file.
- o Delete the sound from the file.
-
- Digital Audio Features
-
- o Cut and paste functions.
- o Broad range of special effects.
- o Zoom in on sound graph image.
- o Spin buttons for fine-tuning editing area.
- o Quality settings for voice, music, high-fidelity.
-
- Audio special effects can be used to alter the sound in a marked area. Special
- effects include: mixing sounds from another file or the clipboard, adjusting
- and maximizing the volume, doubling and halving the speed, fade-in and
- fade-out, reverb, reverse, and echo.
-
-
- ΓòÉΓòÉΓòÉ 3.1.3. Compact Disc ΓòÉΓòÉΓòÉ
-
- The Compact Disc player provides the means for OS/2 users to play music CDs.
-
- When a music CD is inserted in the CD-ROM drive, numbered buttons are displayed
- by the application, indicating track selections. The track button area can be
- scrolled to accommodate discs containing up to 99 tracks. Users can press any
- of these buttons to directly access a track, or they can use familiar CD player
- buttons to move backward and forward in the CD.
-
- Compact Disc Player Features
-
- o Familiar CD player buttons.
- o Direct access to music selections.
- o Disabling and shuffling of tracks.
- o Customized titles for CDs.
- o Small profile.
-
- Options are provided for disabling and reenabling selections, shuffling the
- order tracks are played, and customizing the window title so it displays a name
- for the currently loaded CD.
-
- All this function is packed into a small window, allowing you to fully exercise
- the features of compact disc audio, while reserving the maximum space on the
- desktop for other applications.
-
-
- ΓòÉΓòÉΓòÉ 3.1.4. Multimedia Install ΓòÉΓòÉΓòÉ
-
- Multimedia Install is an easy-to-use, graphical installation program. Building
- on key features of the OS/2 2.1 installation program, Multimedia Install makes
- installation simple, often requiring only one mouse click.
-
- MMPM/2 Install Features
-
- o Easy to use, familiar interface.
- o Serves as an installation engine.
- o Natural way to deliver multimedia products.
-
- What is unique about MMPM/2 Install is that it can be used as an installation
- engine. Text-based control files are created to describe the components of a
- product, which appear as iconic objects within a container control. The objects
- can be selected as a whole, or individually if the user wants to pick and
- choose. Attached to each object is a list of required files and CONFIG.SYS
- updates. Because end users will already be familiar with multimedia
- installation, this program serves as a natural way to deliver new multimedia
- products. For more information, see the MMPM/2 Subsystem Programming Guide.
-
-
- ΓòÉΓòÉΓòÉ 3.1.5. Multimedia Setup ΓòÉΓòÉΓòÉ
-
- The Multimedia Setup application uses the OS/2 2.1 notebook control to provide
- users with a convenient method for maintaining the settings for multimedia
- devices.
-
- Setup Features
-
- o Easy-to-use notebook page.
- o Familiar place for multimedia device control.
- o Set customized name and associated data for each device.
- o Custom pages for unique hardware can be added.
-
- Settings for multimedia devices are presented as pages in a notebook. MMPM/2
- provides settings pages for each media device to allow the name of the device
- to be customized and to allow data files to be associated with the device. In
- addition to the standard settings, custom pages can be inserted into the
- notebook to exploit unique hardware requirements.
-
- The following applications are also provided by MMPM/2. For more information,
- see OS/2 2.1 Using the Operating System.
-
- o MIDI media player
- o Multimedia Data Converter
- o Volume Control
-
-
- ΓòÉΓòÉΓòÉ 3.2. Audio-Enabling Macros ΓòÉΓòÉΓòÉ
-
- Someapplicationsallowuserstoaddafeaturetotheapplicationbyrunningamacro
- .Forexample ,Excel * *andLotus1 - 2 - 3 * *applicationshavethiscapability . OS
- /
- 2multimediaprovidesusersoftheseapplicationswithmacrosthatenablethemtoannotatetheirworksheetswithaudio .
-
- Audio annotation is an effective way to communicate information related to a
- financial work sheet. For example, suppose you are working with a group of
- people on an accounting project. You are using complex formulas in your work
- sheets that need to be explained to members of the group. Audio annotation
- enables you to add the information where and when it is needed.
-
- Using the audio-enabling macro, you can associate a sound file with any cell in
- the work sheet. You record the sound files with a simple recorder provided by
- the audio-enabling macro. And when you select a cell that has audio, its sound
- file plays.
-
- Audio Macro Features
-
- o Easy-to-use audio recorder.
- o Each work sheet cell can be annotated.
- o Annotated cells can be shown, hidden and deleted.
- o Developers can use high-level macro service API to write other macros.
-
- A programming interface is provided, containing the five high-level macro
- functions that are used to record, play, and manipulate the compound file
- elements. Macro functions are also included as 16-bit functions.
-
-
- ΓòÉΓòÉΓòÉ 3.3. Media Control Interface ΓòÉΓòÉΓòÉ
-
- The Media Control Interface provides a full 32-bit device-independent
- programming interface that is modeled after an audio and video home
- entertainment system.
-
- When a user activates a device control to use a multimedia device function, the
- MMPM/2 application window procedure responds by sending a command to the Media
- Control Interface. Depending on the needs of the application, the window
- procedure can use a command message interface or a command string interface to
- implement these device commands.
-
- The command message interface requires the usual C programming constructs,
- which include messages and pointers to data structures, whereas the command
- string interface requires only strings, which are sent to the Media Device
- Manager (MDM) for parsing. For example, an application could send a series of
- string commands to open the Digital Video player and play a portion of a movie
- file.
-
- open movie.avi type digitalvideo alias myvideo wait
- set myvideo time format frames wait
- seek myvideo to 20 wait
- play myvideo to 100 notify
- .
- .
- .
- ** Play the Movie **
- .
- .
- .
- close myvideo wait
-
- Authoring languages that include support for the Media Control Interface can
- integrate device command strings like these with authoring language syntax to
- create multimedia presentations.
-
- In addition to the native 32-bit interface, the string interface can also
- provide a 16-bit interface to enable developers to integrate multimedia
- function with the macro languages of existing 16-bit applications.
-
- The string interface gives applications greater flexibility, because
- application code does not have to be rewritten to support new devices as they
- are added to those supported by the Media Control Interface.
-
-
- ΓòÉΓòÉΓòÉ 3.4. Extendable Device Support ΓòÉΓòÉΓòÉ
-
- The Media Control Interface is a set of defined and extendable media control
- commands. Media driver authors can define new and modified command messages and
- strings to accommodate the hardware their drivers support. How a driver
- communicates with the appropriate hardware device drivers to perform a
- requested command is completely up to the media driver author. This level of
- modularity allows independent development of support for new hardware devices,
- logical media devices, and file formats.
-
- Guidelines are provided for media driver authors who wish to implement
- device-specific support in their drivers. For more information, see the MMPM/2
- Subsystem Programming Guide.
-
- The following logical devices are supported in this version:
-
- o Digital Video
- o Amplifier-mixer
- o Waveform audio
- o MIDI Sequencer
- o CD audio
- o CD-XA
-
-
- ΓòÉΓòÉΓòÉ 3.5. Multimedia Logical Devices ΓòÉΓòÉΓòÉ
-
- MMPM/2 represents audio adapters, CD-ROM drives, and other hardware devices as
- logical media devices that are managed by the Media Device Manager (MDM).
-
- Media devices are a logical representation of the function available from
- either a hardware device, software emulation in combination with hardware, or
- pure software emulation. The actual implementation is not relevant to an
- application, because MMPM/2 provides device independence with the command
- message and command string interfaces.
-
- Frequently there is a one-to-one correspondence between a hardware device, such
- as a CD-ROM drive and its associated media device. Other hardware may be
- represented as multiple logical devices. An example in this category is a
- multi-function audio adapter, which can be represented as waveform audio, MIDI
- sequencer, and amplifier-mixer media devices.
-
- Following are brief descriptions of the logical devices currently supported by
- MMPM/2. For more detailed information, refer to the MMPM/2 Application
- Programming Guide.
-
-
- ΓòÉΓòÉΓòÉ 3.5.1. Digital Video Device ΓòÉΓòÉΓòÉ
-
- The digital video device provides support to applications for playing and
- controlling motion video in a default or application window. The system that
- displays the motion video requires no special hardware, because all video
- presentation is performed using software-only algorithms.
-
- Advances in the efficiency of software motion video algorithms, central
- processor power, data storage, and the display subsystem provide key
- technologies for creating and playing digital video data on personal computers.
- Powerful processors are now available that can handle digital video data in
- real time. And high-capacity hard disks and CD-ROM drives can satisfy the
- storage requirements. These advances combined with today's image compression
- techniques result in the successful integration of video with the personal
- computer.
-
- Digital video files, or movies, are contained in the Microsoft** AVI standard
- file format. Each video frame has been compressed using an algorithm that
- reduces the overall disk storage requirements of the movie, typically by
- removing redundant data both within and across movie frames. The file can also
- contain an associated audio track.
-
- The digital video device is supported by the IBM Ultimotion* algorithm. The
- extendable architecture allows additional compression algorithms to be
- installed as they become available.
-
-
- ΓòÉΓòÉΓòÉ 3.5.2. Amplifier-Mixer Device ΓòÉΓòÉΓòÉ
-
- The MMPM / 2amplifier -
- mixerdeviceisverysimilarinfunctiontoahomestereoamplifier - mixer .
-
- Components are plugged into the amplifier-mixer so that audio signals can be
- transferred to a pair of attached speakers, headphones, or perhaps another
- device. An example in the last category would be playing an old phonograph
- record and recording the sound on a new DAT (Digital Audio Tape) deck. The
- amplifier-mixer serves as the central focus for all audio signals and provides
- input or output switching as well as sound-shaping services such as volume,
- treble, or bass control.
-
- The logical amplifier-mixer device in MMPM/2 supports the connection of both
- analog and digital devices. Other MMPM/2 logical devices may be connected to
- the amplifier-mixer device. Similar to the previous example, the CD audio
- logical device could provide an analog input to the amplifier-mixer device,
- which could then be recorded by the waveform audio device.
-
-
- ΓòÉΓòÉΓòÉ 3.5.3. Waveform Audio Device ΓòÉΓòÉΓòÉ
-
- The MMPM / 2waveformaudiodeviceallowsanapplicationtoplay ,record
- ,andeditdigitalaudiousingfilesorapplicationmemorybuffers .
-
- While audio refers to the sound waves that have a perceived effect on the human
- ear, waveform refers to a digital representation of the original audio sound
- wave. Using one technique called pulse code modulation (PCM), discrete samples
- of the sound wave are encoded by an audio adapter at precise intervals. The
- numerical value of the sample increases when the sound wave's force (loudness)
- increases. The variation of the sample increases as the frequency of the sound
- wave increases.
-
- The number of samples per second taken of the original sound wave as well as
- the precision (or resolution) of the sample dictate the quality of the sound
- reproduction. Typical sampling rates include 44.1kHz, 22.05kHz, and 11.025kHz,
- where kHz is an abbreviation for kilohertz, or thousands of cycles per second.
- The sampling precision is usually measured in bits where 8 or 16-bit samples
- are representative of most audio adapters. Generally, the higher the sampling
- rate and resolution, the higher the perceived quality; however this comes at
- the expense of potentially enormous data rates and file sizes.
-
- One of the typical uses of the waveform audio device is to digitize an input
- signal or sound into discrete samples for storage in a file. An example of
- this would be recording an electronic audio mail message to actually tell
- someone about an idea, as opposed to typing a memo on the same subject. An
- electronic audio mail application would be completely shielded from the
- complexity of digitizing a signal and would only need to specify a file, while
- providing the user with a simple control panel to allow the message to be
- recorded. The user might press a stop button on the control panel when
- finished describing the idea. The application could then issue a stop command
- to the waveform audio device to discontinue the recording.
-
-
- ΓòÉΓòÉΓòÉ 3.5.4. Sequencer Device ΓòÉΓòÉΓòÉ
-
- The MMPM / 2sequencerdeviceprovidessupporttoapplicationsforplayingMIDIsongs .
-
- General MIDI (Musical Instrument Digital Interface) is a standard specification
- for playing back music from a series of commands, rather than actual audio
- data. The commands represent musical events, such as turning a note on and off,
- as well as timing mechanisms for specifying the duration of the note sound.
-
- The MMPM/2 sequencer device plays a MIDI song by sending commands from a MIDI
- file to a synthesizer, where the commands are converted to the sounds of a
- specific instrument. The sequencer uses the timing commands to sequence the
- playing of the music. Typically, a digital signal processor (DSP) is used to
- generate the sounds of the instrument, which results in an authentic
- reproduction of the original performance.
-
- MIDI augments waveform audio as a means of producing sounds in the multimedia
- environment. MIDI data offers the advantage of requiring far less storage than
- waveform data. For example, suppose a three-note chord-middle-C, E and G- is
- held for one second. The storage required to store this information as 16-bit,
- PCM, 44.1kHz, stereo waveform audio data requires 172KB, while the storage
- required for the MIDI commands is only 18 bytes.
-
- Another advantage of storing musical performances as a series of instructions
- is that the information can be edited, the same way words in a document can be
- edited by a word processor. The musical editing process can be used, for
- example, to correct mistakes in an artist's original interpretation, or to
- change certain points of style before playback or final recording. Playback of
- MIDI data using the sequencer media device can be used to reproduce the
- original performance.
-
-
- ΓòÉΓòÉΓòÉ 3.5.5. CD Audio Device ΓòÉΓòÉΓòÉ
-
- The CD( CompactDisc
- )audiomediadeviceprovidesaccesstodevicesthatreadcompactdiscsforthepurposeofplayingCDAudio .
-
- A typical use for CD audio is to provide high quality audio for use in a
- presentation. Another use of CD audio would be to provide detailed audio help
- for an application user. Instead of the usual hyperlinked text and graphics,
- an entire step by step audio tutorial might be stored on a compact disc in
- several different languages.
-
- A mixed-format compact disc holds CD-ROM (Compact Disc-Read Only Memory) file
- system data as well as CD-DA (Compact Disc-Digital Audio) track format data. An
- example of the use of a mixed format disc is an application that contains
- several symphonies by a famous composer. The actual audio is stored as a series
- of CD-DA tracks. Also stored on the disc (but in CD-ROM file format) is a
- program, the actual music score, and perhaps a data base on the composer's
- life. When the application is started, the audio from a symphony can be played
- using the CD audio media driver, while the user is allowed to study the music
- score. Additionally, the user might retrieve facts on the composer, such as how
- old the composer was when the symphony was written.
-
- Depending on the type of CD-ROM drive installed, the audio data on a CD-DA disc
- is either processed by a Digital-to-Analog Converter (DAC) that is built into
- the drive, or it is moved through the system to a Digital Signal Processor
- (DSP) on an audio adapter. Some CD-ROM drives can only play CD-DA audio data
- through the built-in DAC. Others, like the IBM PS/2* CD-ROM-II Drive, can play
- through the DAC, or they can stream data through the audio adapter DSP.
-
- The advantage offered by playing CD-DA through the DAC is that it is a simple
- operation that greatly reduces system and resource overhead. The advantage
- gained by streaming data through an audio adapter DSP is that you can
- potentially enhance the signal beyond the capabilities of a built-in DAC by
- adding special effects with a full-feature DSP-capabilities the built-in DAC
- may not provide.
-
-
- ΓòÉΓòÉΓòÉ 3.5.6. CD-XA Device ΓòÉΓòÉΓòÉ
-
- The CD - XAmediadeviceprovidesaccesstodevicesthatsupportCD - ROM / XAdiscs .
-
- CD-XA (Compact Disc-Extended Architecture) refers to a storage format that
- accommodates interleaved storage of audio, video and standard file system data.
- CD-XA data is stored in a file system format on the discs, and playback control
- is managed by the CD-XA media device in cooperation with the amplifier mixer
- device. The digital audio data is reproduced by an audio adapter, while the
- video and data segements are delivered to the application for appropriate
- processing or display.
-
- CD-XA takes advantage of a special ADPCM audio compression mechanism that not
- only yields a low data rate but also enables more audio data to be stored on a
- disc than that allowed by a CD-DA disc. ADPCM (Adaptive Delta Pulse Code
- Modulation) is an audio compression technique that allows up to a 16 to 1
- compression of audio data.
-
- By compressing the audio data (in some cases to 1/16 the size of CD-DA data) it
- now becomes possible to record multiple audio tracks on a single disc. With
- CD-XA level C, recorded in stereo, it is possible to interleave 8 different
- audio tracks on a single disc. With CD-XA level C, recorded in mono, this
- number climbs to 16 different tracks on a single disc.
-
-
- ΓòÉΓòÉΓòÉ 3.6. Multimedia I/O Services ΓòÉΓòÉΓòÉ
-
- The MultimediaI / O( MMIO )functionsenablesubsystemcomponentssuchasMMPM /
- 2mediadriversandapplicationstoaccessandmanipulateavarietyofdataobjects
- ,includingimages ,graphics ,digitalaudio ,anddigitalvideo
- .Theseobjectscanbestoredinavarietyoffileformatsonavarietyofstoragesystems .
-
- The MMIO manager uses installable I/O procedures (IOProcs) to direct the
- processing of files. There are three basic types of IOProcs: file format,
- compression/decompression (CODEC), and storage subsystem.
-
- A file format IOProc processes the data within the object. Each IOProc handles
- a specific file format and does all the processing required for that file
- format. For example, a MIDI IOProc reads and writes the data that comprises the
- command sequences for the MIDI sequencer. This method of isolating all
- processing that is format-dependent in an IOProc enables applications, media
- drivers, and stream handlers to work with any format supported by an IOProc.
-
- A CODEC IOProc is used to compress and decompress multimedia data. CODEC
- IOProcs are currently used by the digital video media driver to decompress
- video contained in an AVI file. Again, use of the IOProc isolates all system
- components from the particular compression format. New CODEC IOProcs can be
- installed as they become available.
-
- A storage system IOProc unwraps the data object so it can be read and written
- to by a file format IOProc. These IOProcs are independent of the format of the
- data object contained within the wrapper.
-
- A file format IOProc can call upon the services of a storage system IOProc. For
- example, the MIDI IOProc might need to call a storage system IOProc to access a
- MIDI data element stored within a file containing multiple file elements. The
- MIDI IOProc uses MMIO functions to access data from storage system IOProcs
- supported by MMIO.
-
- MMPM/2 has three internal file storage system IOProcs:
-
- ΓöîΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓö¼ΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÉ
- Γöé FILE STORAGE TYPE Γöé DESCRIPTION OF I/O PROCEDURE Γöé
- Γö£ΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓö╝ΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöñ
- Γöé DOS Γöé Manages standard OS/2 disk files. Γöé
- Γö£ΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓö╝ΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöñ
- Γöé MEM Γöé Manages a file in memory without Γöé
- Γöé Γöé accessing the file system. Γöé
- Γö£ΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓö╝ΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöñ
- Γöé CF Γöé Provides functions that operate on a Γöé
- Γöé Γöé Resource Interchange File Format Γöé
- Γöé Γöé (RIFF) compound file to ensure Γöé
- Γöé Γöé storage system transparency at the Γöé
- Γöé Γöé application level. Γöé
- ΓööΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓö┤ΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÿ
-
- MMPM/2 also provides custom file format IOProcs for accessing non-RIFF data in
- standard image, audio, and MIDI file formats. Currently supported file formats
- include OS/2 bit map, Device-Independent bit map (DIB), AVC image, AVC audio,
- SoundBlaster audio, and MIDI. For guidelines on writing a custom IOProc, refer
- to the MMPM/2 Subsystem Programming Guide.
-
- MMIO has a set of options in its API to support two modes of file access:
- translated and untranslated. These modes enable an application to access data
- in its native format, or in a standard format, when performing I/O operations.
- An IOProc can be written to support both access methods.
-
-
- ΓòÉΓòÉΓòÉ 3.7. Stream Programming Interface ΓòÉΓòÉΓòÉ
-
- The StreamProgrammingInterface( SPI
- )providesservicesfortheimplementationofdatastreamingandsynchronizationbymediacontroldrivers
- ,eliminatingtheneedforeachdrivertoprovideitsownsolutionforthesecommonmultimediarequirements .
-
- Pairs of stream handlers implement the transport of data from a source to a
- target device while the Synchronization and Streaming Manager (SSM) provides
- coordination and central management of data buffers and synchronization data.
-
- Making SSM a centralized and architected feature of MMPM/2 guarantees a quality
- system solution to the synchronization of different data streams, which is
- especially significant in advanced multimedia applications requiring
- synchronized audio and video.
-
- The following stream handlers are provided with MMPM/2. Additional stream
- handlers can be installed as required. For more information see the MMPM/2
- Subsystem Programming Guide.
-
- File system System memory
- MIDI mapper Multitrack
- CD-DA audio Audio
- CD-XA Video
-
-
- ΓòÉΓòÉΓòÉ 4. Multimedia Presentation Manager Toolkit/2 ΓòÉΓòÉΓòÉ
-
- Product developerscanincreasetheirproductivitywiththeMMPM / 21 . 1toolkit
- ,whichisincludedonCD - ROMwiththedeveloper ' stoolkitforOS / 22 . 1
- .IncreasedproductivitybeginswithasimpleinstallationfromCD -
- ROMusingthemultimediainstallationprogram .
-
- MMPM/2 Toolkit Features
-
- o Fully documented sample programs.
- o Sample code for all major functions.
- o Captioning system
- o Useful tools in Neat Stuff folder
- o Audio Recorder sample
-
- Once installed, the toolkit sample programs illustrate the use of the
- comprehensive multimedia device and data handling capabilities of MMPM/2.
- There are working sample programs for every major function in the MMPM/2
- system. As the sample code can be freely incorporated into real products,
- developers can be immediately productive without incurring a steep learning
- curve. Product developers will be able to focus on product-specific function
- instead of investing large amounts of time providing the multimedia
- enhancements. The MMPM/2 technical library provides detailed information and
- discussion on each sample program.
-
- Complete online documentation provides a quick effective reference to all
- system APIs, messages, and features, including code examples and helpful notes.
-
-
- ΓòÉΓòÉΓòÉ 4.1. Complementary Products from IBM ΓòÉΓòÉΓòÉ
-
- OS/2 Device Driver Source Kit
-
- The Device Driver Source Kit for OS/2 contains documented source code and
- detailed information on how to build device drivers for OS/2 and MMPM/2.
-
- The kit covers the complete range of OS/2 physical and virtual device drivers,
- from printers, displays, SCSIs and CD-ROM drives, to the device drivers for
- PenPM and MMPM/2. Comprehensive descriptions of all the device driver
- interfaces and system services are included.
-
- Coming Soon to an OS/2 System Near You
-
- A digital motion video product will be available soon from IBM that provides
- creation and editing facilities for digital video. Movies created with this
- product can be played back by the software support already shipped with every
- copy of OS/2 2.1.
-
-
- ΓòÉΓòÉΓòÉ 5. Summary ΓòÉΓòÉΓòÉ
-
- Operating System/2 2.1 will have a significant impact on how people use
- computers in the '90s. Even more significant will be its initial impact on
- software developers. With OS/2 2.1, a developer can enjoy the productivity
- benefits of developing with a 32-bit, preemptive multitasking operating system.
-
- For multimedia applications, OS/2 2.1 has the technology to provide viable
- business solutions. Preemptive multitasking means that no application will
- unnecessarily consume the precious resources of the processor. Because this
- policy is enforced by the operating system, there is no need to rely on the
- good will of other application developers as in a cooperative multitasking
- system. This is especially important for multimedia applications where
- consistent throughput is essential in order to maintain the quality of a
- presentation.
-
- Also essential to multimedia applications is the demand-paged virtual memory
- support in OS/2 2.1. Memory usage is optimized and the flat memory model can
- make programming a breeze. Memory is seen as a completely linear space up to
- 512MB. As with all previous versions of OS/2, version 2.1 provides protected
- memory to guarantee a stable development and end user environment.
-
- The addition of Multimedia Presentation Manager/2 (MMPM/2) creates a premier
- multimedia programming environment. All hardware devices are controlled
- through a full-feature, 32-bit, device-independent programming layer called the
- Media Control Interface. Developed as a joint standard between IBM and
- Microsoft Corporation, the Media Control Interface greatly reduces the expense
- of adding multimedia capabilities to applications. In addition to insulating
- applications from the underlying hardware, MMPM/2 also shields applications
- from different data formats and provides a completely extensible architecture
- to allow the incorporation of new multimedia devices and multimedia data
- formats. A centralized synchronization and streaming manager provides
- dependable data transport and synchronization services.
-
- Based on the solid technological foundation of OS/2 2.1, the Multimedia
- Presentation Manager/2 brings a literal explosion of sights and sounds to
- modern personal computing.
-
-
- ΓòÉΓòÉΓòÉ 6. Related Technical Information ΓòÉΓòÉΓòÉ
-
- The Multimedia Presentation Manager Toolkit/2 includes an online programming
- reference and a Getting Started publication. The following related publications
- can be ordered separately by calling 1-800-IBM-PCTB.
-
- MMPM/2 Application Programming Guide - (71G2221)
- Provides guidelines for developing MMPM/2 applications. Code examples
- from fully documented sample programs accompany the descriptions of
- the application programming interfaces.
-
- MMPM/2 Subsystem Development Guide - (71G2223)
- Provides guidelines for developing multimedia subsystems. Each
- subsystem component is described in detail in individual chapters.
- Models are used to complement the information provided by component
- sample program templates.
-
- MMPM/2 Programming Reference - (71G2222)
- Provides detailed information on multimedia functions, messages, and
- data structures to enable you to write code for your multimedia
- application programs and subsystems.
-
- Guide to Multimedia User Interface Design - (41G2922)
- Describes design concepts to be considered when designing a CUA
- multimedia interface that is consistent within a particular
- multimedia product and across other products.
-
-
- ΓòÉΓòÉΓòÉ 7. Trademarks ΓòÉΓòÉΓòÉ
-
- The following terms, denoted by an asterisk (*) in this publication, are
- trademarks or service marks of the IBM Corporation in the United States or
- other countries:
-
- CUA Common User Access
- OS/2 Operating System/2
- PS/2 Personal System/2
- IBM
- Ultimotion
- Multimedia Presentation Manager/2
- Multimedia Presentation Manager Toolkit/2
- Presentation Manager
- Workplace Shell
-
- The following terms, denoted by a double asterisk (**) in this publication, are
- trademarks of other companies as follows:
-
- Microsoft Microsoft Corporation
- Windows Microsoft Corporation
-
- Copyright International Business Machines Corporation 1993. All rights
- reserved
- Note to U.S. Government Users - Documentation related to restricted rights -
- Use, duplication, or disclosure is subject to restrictions set forth in GSA ASP
- Schedule Contract with IBM Corp.
-
-
- ΓòÉΓòÉΓòÉ <hidden> ΓòÉΓòÉΓòÉ
-
- When you place a bookmark on a topic, it is added to a list of bookmarks you
- have previously set. You can view the list, and you can remove one or all
- bookmarks from the list. If you have not set any bookmarks, the list is empty.
-
- To set a bookmark, do the following:
-
- 1. Select a topic from the Contents.
-
- 2. When that topic appears, choose the Bookmark option from the Services menu.
-
- 3. If you want to change the name used for the bookmark, type the new name in
- the field.
-
- 4. Select the Place radio button (or press the Up or Down Arrow key to select
- it).
-
- 5. Select OK. The bookmark is then added to the bookmark list.
-
-
- ΓòÉΓòÉΓòÉ <hidden> ΓòÉΓòÉΓòÉ
-
- You can specify a word or phrase to be searched. You can also limit the search
- to a set of topics by first marking the topics in the Contents list.
-
- To search for a word or phrase in all topics, do the following:
-
- 1. Choose the Search option from the Services pull-down.
-
- 2. Type the word or words to be searched.
-
- 3. Select All sections.
-
- 4. Select Search to begin the search.
-
- 5. The list of topics where the word or phrase appears is displayed.
-
-
- ΓòÉΓòÉΓòÉ <hidden> ΓòÉΓòÉΓòÉ
-
- You can print one or more topics. You can also print a set of topics by first
- marking the topics on the Contents list.
-
- To print the document Contents list, do the following:
-
- 1. Select Print from the Services menu.
-
- 2. Select Contents.
-
- 3. Select Print.
-
- 4. The Contents list is printed on your printer.
-
-
- ΓòÉΓòÉΓòÉ <hidden> ΓòÉΓòÉΓòÉ
-
- You can copy a topic you are viewing into a temporary file named TEXT.TMP. You
- can later edit that file by using an editor such as the System Editor.
-
- To copy a topic, do the following:
-
- 1. Expand the Contents list and select a topic.
-
- 2. When the topic appears, select Copy to file from the Services menu.
-
- The system copies the text pertaining to that topic into the temporary TEXT.TMP
- file.
-
- For information on any of the other choices in the Services menu, highlight the
- choice and press the F1 key.
-
-
- ΓòÉΓòÉΓòÉ <hidden> ΓòÉΓòÉΓòÉ
-
- You can control the appearance of the Contents list.
-
- To expand the Contents and show all levels for all topics, select Expand all
- from the Options menu.
-
- For information on any of the other choices in the Options menu, highlight the
- choice and press the F1 key.
-
-
- ΓòÉΓòÉΓòÉ <hidden> ΓòÉΓòÉΓòÉ
-
- Trademark of the IBM Corporation
-
-
- ΓòÉΓòÉΓòÉ <hidden> ΓòÉΓòÉΓòÉ
-
- Trademark of the IBM Corporation.
-
-
- ΓòÉΓòÉΓòÉ <hidden> ΓòÉΓòÉΓòÉ
-
- Based on system configuration with a 25Mhz 386 processor and SVGA or XGA video
- support.
-
-
- ΓòÉΓòÉΓòÉ <hidden> ΓòÉΓòÉΓòÉ
-
- Trademark of the Intel Corporation.
-
-
- ΓòÉΓòÉΓòÉ <hidden> ΓòÉΓòÉΓòÉ
-
- Trademark of the Microsoft Corporation
-
-
- ΓòÉΓòÉΓòÉ <hidden> ΓòÉΓòÉΓòÉ
-
- Trademark of the Lotus Development Corporation
-
-
- ΓòÉΓòÉΓòÉ <hidden> ΓòÉΓòÉΓòÉ
-
- Trademark of the IBM Corporation.
-
-
- ΓòÉΓòÉΓòÉ <hidden> ΓòÉΓòÉΓòÉ
-
- Trademark of the Microsoft Corporation