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Multimedia Under Windows NT


Multimedia is another big area of improvement under Windows NT. The CD-ROM ships with several samples of multimedia presentations. They don't fully exploit the potential of multimedia, but they do give you an idea of what's possible. I foresee a lot of people using this media for interactive training. The instructor could appear in a corner of the screen and provide you with interactive instructions as you perform a task.

Multimedia will change the way we conduct business in other ways. Instead of flying a group of people to one place to see a presentation, you could send the presentation to the group of people using a CD-ROM. This same group could meet using conferencing software and discuss the presentation's impact and viability. Air travel might not become a thing of the past, but using the multimedia capabilities that Windows NT is starting to provide will help reduce the need to travel.

Notice that I said Windows NT is only starting to provide this capability. The cost of building a multimedia machine that will really do the job is still fairly high. Using something less than optimum almost always results in a presentation that lacks the pizzazz of a live presentation. We also have a long way to go before interactive training is a real option. It's getting closer, and the Windows NT demonstration programs show this, but it's still not perfect. Multimedia still needs improvement in some areas before anyone can say that it's ready.

Warts aside, multimedia under Windows NT is greatly improved. The sections that follow give you an overview of multimedia under Windows NT and how it enables you to better exploit your hardware. Right now, it's hard to say who's ahead in the game—hardware or software. Neither is it to the level where I'd say that it gives you the kind of presentation you're looking for. I'll leave it for you to decide just how far it has to go.

Future Shock: 3D Multimedia


Microsoft and Apple are both working on a variety of multimedia standards that will take you from a 2D world to that of 3D. We all have a pretty good idea of how 3D video works, but these standards include a lot more. The stereo you hear from a speaker will provide clues that enables you to define a direction for a particular sound, for example. Not only that, but the sound will be richer—sounding a lot more like the real thing than something canned and replayed later. Both companies are working on a 3D multimedia API (application programming interface) that will allow programmers to add these new features to the applications you use. You might even see some of this support in Windows NT. (The actual decision to include some of the 3D API features wasn't made at the time of this writing.) Imagine the effect of such a breakthrough on presentations—not to mention entertainment software.

Anyone who's used the current crop of multimedia products also realizes that they're pretty slow. I've got a 4X CD-ROM drive attached to one machine and a 6X CD-ROM drive attached to the other. Both drives still have problems with stops and delays in displaying multimedia information on-screen. This jerkiness is part of the reason that current multimedia presentations lack that extra measure of realism that people expect. These new APIs are also supposed to fix at least part of that problem by optimizing the multimedia environment. I won't go so far as to say that your multimedia presentations will be perfect, but every little bit helps. Some companies are taking advantage of this improved performance in the Internet products they're creating. The speed boost comes from a vendor's ability to use direct hardware calls within an application. I discuss the architecture behind graphics in Windows NT in Chapter 10, "Graphics NT Style." Looking through that chapter, you'll see that an application currently goes through a lot of layers of software to get to the display adapter. What the direct hardware commands will do is tell Windows to send a command directly to the display adapter—offloading part of the processing burden for the CPU without bypassing the operating system.

What will you need to use these new features? (You didn't expect it to come free—did you?) One of the requirements will be a complete MPEG hardware setup. (I'll talk about MPEG in the section "Multimedia Standards" later in this chapter.) According to some folks, the Direct3D API (Microsoft's form of 3D multimedia API) will be able to emulate some of the hardware needed to make this all happen, but my experience with emulation in the past tells me that you'll be better off getting the hardware you need up front. You'll also need a MPC Level 3 machine—I'll talk about precisely what that means in the next section as well. 3D multimedia won't be cheap anytime in the near future.

Microsoft has made some progress in this direction already. A recent trade press article mentioned that they might be able to deliver part of the 3D multimedia API for Windows 95 around the middle of 1996. Some level of support is also supposed to ship with Windows NT, but I'll wait to see if that actually happens. What are the current pieces? Besides the Direct3D API, which provides the 3D multimedia affect and the boost in multimedia performance, there are four other pieces in place. The Direct Input, Direct Play, Direct Sound, and Direct Draw APIs all provide standard 2D features in current multimedia. They do it in such a way that the CPU spends a lot less time processing multimedia commands, however; everything is offloaded to the processor on the video or sound board. Future pieces (at least the ones that Microsoft will talk about) include a Direct 3D Audio and Direct MPEG API. Just what features those APIs will provide is uncertain right now. I think we'll all find that multimedia is a bit crisper and faster though once these APIs are released.

Multimedia Standards


I'm not going to tell you about every multimedia standard that ever was in this section of the chapter. What I will tell you about is some of the more recent standards—those that will affect you in the immediate future. This section will focus on industry-wide standards that really don't affect Windows NT as much as they affect the equipment you buy or the applications you use. Other sections of the chapter will tell you about Windows NT specific levels of support. With all this in mind, take a look at Table 16.1, which provides a list of some of the standards that you'll want to follow when working in the realm of multimedia.

Table 16.1. General multimedia standards.

Standard Description
MPC Level 1 The MPC (Multimedia PC Marketing Council) Level 1 specification is the minimum level of equipment support you can provide to run any kind of multimedia application. It includes a CD-ROM with a 150KB/sec transfer rate and 1,000ms access time, a 640x480 video adapter capable of displaying 16 colors, an 8-bit sound card capable of 22.05KHz playback, a 16MHz 386SX processor, 2MB of RAM, and 30MB of hard disk space. Obviously, these are very minimal requirements—probably not what you'd want in a working machine today. An MPC Level 1 machine will probably work fine as a home machine, but you might find that it won't work with some games.
MPC Level 2 The Level 2 standard appeared in 1993 when it became obvious that Level 1 support was insufficient for most multimedia needs. To meet the requirements of this standard, your machine must provide the following hardware: a CD-ROM with a 300KB/sec transfer rate and 400ms access time, a 640x480 video adapter capable of displaying 65,536 colors, a 16-bit sound card capable of 44.1KHz playback, a 25MHz 486SX processor, 4MB of RAM, and 160MB of hard disk space. This machine probably represents the minimum you would want for an office machine of any kind today. You certainly wouldn't want to send this kind of machine on the road with your sales staff.
MPC Level 3 As computers evolved, so did computer standards. I consider this the minimal setup for anyone who's serious about multimedia today. You'll need the following equipment to meet MPC Level 3 standards: a CD-ROM with a 600KB/sec transfer rate and 250ms access time, a 640x480 video adapter capable of displaying 16.7M colors, a 16-bit sound card capable of 44.1KHz playback, a 75MHz Pentium processor, 8MB of RAM, and 540MB of hard disk space.
ISO 8879 Standard Generalized Markup Language (SGML): This is a method for storing formatted documents. A superset of HTML (hypertext markup language), SGML enables you to store the document's logical structure and layout information in a standard way. You'll probably see this used on the Internet more than anything else. What does this have to do with multimedia? Take a look at the ISO 10744 standard later in this table.
ISO 9660 CD-ROM Volume and File Structure: This is the standard that enables you to read a data CD on your machine. Before this standard, there were actually several different ways to format a CD—all of them incompatible. You couldn't read a CD formatted using a different technique. Imagine the chaos if you had to ensure that every CD you bought was in the right format. This isn't the only CD standard, but it's one that you should be aware of.
ISO 10744 HyTime: This is a hypertext/multimedia extension to SGML. Essentially, it specifies one of the ways that you'll get multimedia data from the Internet in the future.

MPEG Support


Motion pictures revolutionized the world, and now they'll revolutionize your PC. MPEG (Motion Pictures Experts Group) is a standards group that created a method of compressing VHS video into a very small format that will fit on a CD-ROM. VHS is the same format your VCR uses. In essence, this standard tells how to display a taped television presentation on your computer's display. This group actually does a lot more work than simply define video display techniques, but I'll concentrate on this particular standard because that's what Windows NT supports.



Note: The term MPEG is actually used as a matter of convenience. The real name for this group is ISO/IEC JTC1 SC29 WG11. What does that name mean? The following lines show you how an ISO standards group name is created.

ISO: International Organization for Standardization

IEC: International Electro-Technical Commission

JTC1: Joint Technical Committee 1

SC29: Sub-committee 29

WG11: Work Group 11

Now that you know what the full name is, aren't you glad someone came up with the shorter MPEG name? The reason you'll want to know the full-fledged name is two-fold. For one thing, you'll need it if you ever want to write and ask for copies of the standards they create. Second, a lot of those standards are available for download on the Internet under the group's full name.


The technical term for the type of functionality that MPEG provides is a codec (coder/decoder). Think of a codec in the same way you would think of a modem. It enables you to send and receive video data using a standard medium. Instead of a telephone wire, you're using a CD-ROM drive. In place of digital data, you're receiving video images.

Windows NT currently provides the capability to display VHS-quality images in a 640x480 window at 30 frames per second. That's about the same rate that you see on television. You're supposed to get this level of performance from a double-speed CD-ROM drive, but I have a quadruple-speed unit connected to my system and I just barely get what I would call acceptable performance. I'm sure part of Microsoft's assumption is that you won't be running anything else when using the multimedia capabilities, but that probably isn't very valid. Most people will want to use this capability for training, which means that they'll probably have another application open.

MPEG support actually has two levels, but don't get your hopes up for something spectacular from the user's point of view. The new standard simply tells how to do a better job of compressing the data. What you'll see is a crisper display with fewer interruptions. You won't see a higher frame rate or a larger image; those changes will have to wait for high definition television and other non-computer–related technologies to become established.

If you want to fully exploit your machine's hardware capabilities to perform training, using MPEG technology is one way to do it. Make sure you get more than a minimal system if you plan to use the multimedia capabilities Windows NT provides on more than an occasional basis. Otherwise, you'll probably be disappointed with the performance that low-end hardware will provide.



Tip: I haven't covered any more than the user's perspective of MPEG in this section. You can quickly get mired in detail with this particular Windows feature because there are a lot of non-computer–related topics to cover. Some of you might want to know more, though. MPEG is a draft ISO standard named ISO CD 11172. The three sections to the standard are system, video, and audio. The system part (ISO CD 11172-1) deals with synchronization and multiplexing of audio-visual information. The video section (ISO CD 11172-2) addresses video compression techniques, whereas the audio section (ISO CD 11172-3) discusses audio compression techniques. There are two places to get these standards if you can't find them on the Internet or other online services such as CompuServe.

ISO Sales
Case Postale 56
CH-1211 Geneve 20
Switzerland

ANSI
Attn: Sales
11 West 42nd Street
New York, NY 10036
Phone: (212) 642-4900



Sound Boards


I've had sound for so long that I can't imagine using Windows without it. In fact, you've probably had it that long, too. Why even mention it here? What does Windows NT provide that Windows 3.x didn't?

There are all kinds of sound. You don't have to settle for the mediocre level of sound that Windows 3.x provided. Windows NT provides the controls required to fully exploit the expanded capabilities that modern sound boards provide. All you need to do to start using these capabilities is to adjust the settings found in the Audio Properties dialog box. To access this dialog box, right-click the Speaker icon on the Taskbar and select Adjust Audio Properties. You should see a dialog box similar to the one shown in Figure 16.1.

Figure 16.1. The Audio Properties dialog box enables you to make full use of the audio capabilities your system provides.

Windows NT will always play back any audio using the full capability of the sound board you select. You have a lot of room to customize the recording of sound, however. Microsoft thoughtfully provided three default recording selections. Each selection reflects the kind of sound recording quality these settings will give you: CD, radio, or telephone.

The actual level of quality you get has to do with the frequency, or the number of samples of sound that Windows takes per second. The more samples it takes, the better the quality of your sample. Using stereo and 16-bit samples also improves the sound quality, as does the recording format. Before I go much further, I want to define the following terms:

Now that you have some ideas of the ways you can customize sound under Windows NT, look at the dialog box you use to do it. Click the Customize button to see the Customize dialog box, shown in Figure 16.2.

Figure 16.2. Use the Customize dialog box to change the way you record sound under Windows NT.

Notice that there are two listboxes. One determines the recording format, and the other allows you to select from a variety of options, including the sample rate, sample size, and number of channels. Notice that this listbox also tells you the storage requirements for the sample in kilobytes per second. This is the number of kilobytes that the sample would consume for each second you recorded. Obviously, some formats can eat a lot of storage space quickly.

You can save any custom settings that you create using the Save As button. Windows will store the settings and present them later in the Preferred Quality listbox of the Audio Properties dialog box.

What's the best way to customize these settings? Remember that the better the quality, the higher the storage requirements. I tend to prefer stereo over mono recordings because the depth of sound can make up for a host of other problems. The trouble is if you have only one microphone, selecting stereo is a waste of disk space because you can record only one channel of information. Selecting 16-bit sound improves quality a great deal for a very small increase in storage size. You get a sample 2[16] (65,536 possible combinations) versus 2[8] (256 possible combinations) for a mere doubling of disk space. Unless you're recording music, the highest sampling rate you need is 22,050Hz. In fact, using 11,025 for simple voice recordings usually proves sufficient.

Video Cards


This section of the chapter looks at video cards from a multimedia perspective. Look in Chapter 14, "Exploiting Your Hardware," if you want to learn how to install a video card or monitor. What kinds of things will you need to examine under Windows NT when it comes to multimedia? The first thing you should do is get an MPEG-compliant video adapter if you plan on providing a lot of training sessions or media presentations. I discuss the importance of MPEG in the section "MPEG Support" earlier in this chapter.

Part of the reason for getting an MPEG adapter exists today; they're usually designed to display full-motion video and other types of animated graphics at a higher speed than a standard adapter. Another part of the picture is the 3D multimedia support that Microsoft and Apple are working on. I cover this topic in the section "Future Shock: 3D Multimedia" earlier in this chapter.

Now that I've discussed the performance issues from a hardware perspective, take a look at a few software issues. The multimedia settings for your display adapter don't appear on the Display Properties dialog box like all the other settings do. Double-click the Multimedia applet in the Control Panel and select the Video page. You'll see a dialog box similar to Figure 16.3. The video multimedia settings are pretty easy to figure out. The two modes of operation are Full Screen and Window. If you do select Window, you can choose between the original size or something smaller/larger as needed.

Figure 16.3. The multimedia settings for your display adapter appear on the Video page of the Multimedia Properties dialog box.

You need to consider a few things when looking at these settings. One of the most important issues is speed versus display size. If you're giving a presentation, it's really distracting to see the other things on your desktop while displaying a video. In addition, your audience might find it difficult to see your presentation at the back of the room if you display it normal size. In most cases, you'll want to use the full screen in this situation (or at least clean up your desktop).

Displaying a video full screen won't enhance its resolution. No matter what size you make the video, you're still seeing the same number of pixels—some of them get repeated to make the screen larger. The effect of this loss of resolution during a training session can get quite distracting. Training videos also tend to use the CD more—especially if you make them interactive. A higher level of CD access means that you'll need every bit of performance out of your machine. A smaller display area is one of the ways you can get that extra performance without degrading the training experience in any way.

CD-ROM Drives


Before I discuss the Windows end of CD-ROM multimedia, I'd like to spend a little time discussing some hardware issues that I've seen more than a few people stumble over. CD-ROM drives usually have two connections that you need to worry about. The first is the SCSI connector that allows data transfer between the computer and the CD-ROM. Some older CD-ROMs don't use a SCSI connector; they use a proprietary card instead. The principle is the same, but the data transfer is a lot slower. The SCSI connector for a CD-ROM serves the same purpose as the equivalent connector for your hard drive. It enables you to transfer data from the CD-ROM to your machine.



Tip: The price of CD-ROM recorders has dropped significantly in recent months. In the near future, it might become possible to buy a CD-ROM recorder for about three times the price of a player. Buying a CD-ROM recorder instead of a player has two advantages. First, you can use it to make archive copies of CDs. Despite popular folklore, CDs are resistant but not impervious to damage. Considering the cost of some CDs and the less-than-thrilling replacement policy some vendors have, an archive copy could make a big difference when the inevitable does occur. Second, you could use a CD-ROM recorder in place of a backup tape. The permanent nature of the backup makes it a medium of choice in cases where long-term storage is desired, such as with law firms and the medical community. A CD-ROM backup is also faster than some types of tape backup, although I won't say that you can't get better performance out of some DAT tapes. One thing is certain: The random-access feature of a CD makes it a lot faster than a tape for data retrieval.

Some people don't really think about the second connection. They'll try to use the CD-ROM with a game or another application that plays sound right off the CD—just like you would with a music CD—and discover that the game doesn't appear to work with their machine. The problem is that they don't have the RCA plugs in the back of the CD-ROM drive connected to anything. External CD-ROM drives use the RCA connectors (the ones that look like the speaker connectors on your stereo). Internal CD-ROM drives usually require some type of special connector for your sound card. This is a proprietary connector in some cases; in other cases, the vendor will try to make you believe that their common cable really is proprietary. Check with your local computer store to see if they have an inexpensive alternative to the expensive cable that the vendors usually offer.



Peter's Principle: How Much Speed Do You Need?

After you get the connectors in place, your CD-ROM drive is ready to go. The speed at which it goes is cause for concern for many people, however. Although a single-speed CD-ROM drive might be adequate for data transfer, it won't work for multimedia applications at all. I recently bought a CD game. The sound was great on my 4X (four-speed) CD-ROM drive, but the same CD sounded very jerky and hesitated a lot on my 1X drive. The need for speed isn't just a matter of perception on the part of a few power users. There are 6X and even 8X CD-ROM drives now—some people are still complaining about jerky presentations as the load on these drives increases.

There's a gray area when it comes to other drive speeds. A 2X drive will probably work for the majority of games because game vendors try to get every ounce of speed from them that they can. On the other hand, you'll probably get very poor results for many multimedia education products. Don't even think about using a 2X drive for full-motion video. A 3X drive is marginal for full-motion video. Plan on missing some frames. It'll work perfectly with the vast majority of educational multimedia applications and just about every game out there.

Of course, there are other performance factors as well; the same factors that affect the performance of your hard drive affect CDs as well. Things such as bus width and hardware caches can make a big difference in the actual performance you'll see. Even the controller you choose will make a big difference in the performance you'll get from your CD. It hardly pays to use a 16-bit controller with a 4X CD drive. You'll want to maximize performance by using a 32-bit controller instead.

Buying the best CD-ROM player available is probably a good idea when you consider the small price differential between them. If you're on a tight budget and need to get the best value for your money, however, try to match the speed of your drive with the type of use it will get. A drive that is too slow for the job will only frustrate you and make it impossible to actually do the required work. Just imagine the effect of a multimedia presentation in which a slow drive, rather than your stunning graphics and sound, grabs the audience's attention.


Besides the other connections on your CD-ROM drive, the front has a headphone connector. Imagine my surprise when I plugged in some headphones and heard sound out of my speakers and headset at the same time. Some vendors disable the speaker output when you plug in the headset; others don't. You'll want to check out this feature if this is an important consideration for your application.

Now I want to spend some time looking at how Windows interacts with your CD-ROM drive and what you can do to improve its performance. Open the Multimedia Properties dialog box by double-clicking the Multimedia applet in the Control Panel. Select the CD Music page and you'll see a dialog box similar to Figure 16.4. The controls on this page are easy to understand; they enable you to change the headphone level of a specific drive. Unfortunately, Windows NT 4.0 doesn't provide the handy performance-tuning features provided with Windows 95. Hopefully, Microsoft will provide these features in the next revision of Windows. Also, make sure you spend some time looking at the various tuning tips I provided for this dialog box in Chapter 3, "Performance Primer."

Figure 16.4. The CD Music page of the Multimedia dialog box controls only the sound level of your speakers, not the performance issues you might expect.

MIDI


Getting decent MIDI (musical instrument digital interface) performance out of a computer hasn't been an issue for quite a while. In fact, MIDI has been one of the few areas where a computer can get the job done for the most part. The level of MIDI support under Windows NT is about the same as what you had under Windows 3.x. This is probably one of the few stable areas of your machine.

Accessing the MIDI settings for your machine is easy. All you need to do is select the MIDI page of the Multimedia Properties dialog box. You can display this dialog box by double-clicking the Multimedia icon in the Control Panel. What you'll see is a dialog box similar to Figure 16.5.

Figure 16.5. The MIDI page of the Multimedia dialog box gives you complete control over your computer's MIDI settings.

The default Single Instrument setting enables Windows to configure the MIDI setup for you as needed. That's what you'll need to play MIDI files because part of the MIDI file definition configures the instruments and other features of the interface. Professional musicians use special applications to create these setup files as part of the "recording" process. If you want to change the MIDI settings to get a particular effect, you need to select the Custom Configuration option at the bottom of the page. Before you can really use the custom setting, however, you need to add a few instruments (either external or as part of a definition file) to your setup. Click the Add New Instrument button and you'll see the MIDI Instrument Installation Wizard shown in Figure 16.6.

The first thing you'll need to do is select a port. Usually, this isn't a big deal because most of us only have one MIDI port; it's attached to your sound card. Professional musicians might have four, eight, or even more ports at their disposal. They have to select the port that they'll use to control a particular instrument. Once you select a port, click Next. You'll see a dialog box similar to the one shown in Figure 16.7.

Figure 16.6. The MIDI Instrument Installation Wizard enables you to add instruments to your computer's setup—the first step in creating a custom configuration.

Figure 16.7. Defining the instrument is the second step to adding an instrument to your MIDI configuration.

What Windows is asking for here is an instrument definition. The only time you actually have to define an instrument is if it doesn't exist in the real world. Say you want to add a drum to your setup, but you don't have one to connect to an external MIDI connection. Using a definition file would enable you to add the drum even though it doesn't exist. If you click Next here without adding an instrument definition, Windows will assume that you want to use an external instrument. Notice the Browse button; it allows you to find a definition file on disk. Add an instrument definition if you'd like and then click Next. You'll see the dialog box shown in Figure 16.8.

Figure 16.8. The last step of the process is to give your instrument a name.

The last MIDI Instrument Installation Wizard dialog box enables you to give your instrument a name. You don't have to accept the default that Windows provides; in fact, you'll definitely want to provide something more interesting than External MIDI Instrument. Type in a new name for your instrument and click Finish to complete the process.

You'll need to use the MIDI Instrument Installation Wizard to add all the instruments you plan to use for a particular setup. Once you get this done, you can actually create a custom setup. Select the Custom Configuration radio button on the MIDI page of the Multimedia Properties dialog box (refer to Figure 16.5). If you click the Configure button, you'll see a dialog box similar to Figure 16.9 where you add instruments to particular MIDI channels.

Adding an instrument to a channel is fairly easy. All you need to do is select the channel that you want to use and then click the Change button. You'll see the Change MIDI Instrument dialog box shown in Figure 16.10. The edit box contains the name of the channel. The drop-down listbox contains the list of instruments that you've defined. Just select an instrument from the list as shown in the figure. Click OK to make the change permanent.

Figure 16.9. The MIDI Configuration dialog box enables you to assign instruments to specific channels of your MIDI port.

Figure 16.10. The Change MIDI instrument dialog box shows the status of a particular channel.

Once you've assigned all the instruments you need to particular channels, you can save the configuration for later use. Clicking the Save As button on the MIDI Configuration dialog box will display a simple dialog box containing a single field. Type in the configuration name and click OK to make the configuration permanent. You'll be able to reopen the configuration later as needed to reset your MIDI configuration to obtain particular effects. Windows displays these configurations in the MIDI Scheme drop-down listbox on the MIDI page of the Multimedia Properties dialog box.

On Your Own


Perform a survey of your computer to see how multimedia ready it really is. Does it pass all the requirements for MPC Level 1? Try using a third-party product such as TouchStone's CheckIt to perform an audit on your system. (I describe this product in Chapter 26, "Windows NT Maintenance Programs.")

Spend some time reviewing the motion picture clips provided with Windows NT. How does varying the size of the display affect playback performance? Do you see any increase in resolution by changing the picture size?

Try recording the same audio sample using various quality settings and then playing the sample back to see the effect of using that setting on how you perceive the recording. Make sure that you record a variety of samples. Voice recording is a lot less demanding than music, for example. Try sound effects as well if you use them in presentations. Figuring out precisely what recording levels give the best response on your equipment is a real plus—especially if you're using a marginal multimedia system.

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