|Archived content. No warranty is made as to technical accuracy. Content may contain URLs that were valid when originally published, but now link to sites or pages that no longer exist.|
Abstract:Adapted from a Microsoft TrainCast script, this article discusses multimedia support under Windows 95, with emphasis on troubleshooting—determining the causes of problems, corrective actions, preventive measures. It addresses Windows multimedia features, video, CD-ROM, audio and support issues. Each section includes references to Knowledge Base articles on multimedia topics.
By Micheal Dunn and Brian Constable
Multimedia is one of the fastest growing areas of the software industry. Products range from games to presentation packages to Internet browsers. A CD-ROM drive is a standard feature on every new PC, as are sound subsystems and local-bus video.
Windows has been involved in multimedia since version 3.0. Here are some milestones:
On This Page
Windows Multimedia History
1991—Windows version 3.0 with Multimedia Extensions 1.0: Released through OEMs only, this first version of a multimedia subsystem for Microsoft Windows included support for:
Wave audio—Digitized audio data.
Joystick services—Calibration for joystick devices.
MIDI—Data files conforming to the Musical Instrument Digital Interface protocol specification.
CD Audio—For playing audio compact disks
1992—Windows version 3.1: This was the first version of Microsoft Windows to include a multimedia subsystem incorporated into the base operating system. It included out of the box support for:
1992—Video for Windows: This product allowed playback and recording, with the appropriate hardware, of AVI files. Video for Windows also implemented a compression/decompression structure for video files.
1993—Microsoft Multimedia Pack 1.0: This product was released on CD-ROM and was available exclusively through Multimedia hardware OEMs. It consisted of the Windows version 3.1 base operating system with additional enhanced utilities including:
Media Browser—Browse the system for multimedia data files (.AVI, .MID, .RMI, .WAV, etc.)
Minesweeper (multimedia version)—Wave audio support was added to Minesweeper.
Music Box—CD Audio playback application.
Sound Recorder—Enhanced to support multiple sampling rates and compressed audio files.
Video for Windows (VFW) 1.1—VFW 1.1 included the Audio Compression Manager (ACM).
Windows 95 Multimedia Features
NOTE The Knowledge Base contains many articles on Windows 95 and multimedia issues, and it is the best place to look for general and troubleshooting information. The KB is available on the MSN, CompuServe, AOL, Genie, the Microsoft Web site, and TechNet.
Microsoft Windows 95 includes features and improvements from Windows version 3.1 and raises the bar for the baseline multimedia support in Windows. The user interface is vastly improved, making it easier to install, remove, and control multimedia devices.
32-bit compression/decompression services for audio and video—For faster and better multimedia support.
Run-time version of Video for Windows—Vendors creating Windows 95 applications can now assume that the user's machine will support AVI video clip playback.
General MIDI support—General MIDI is a standard for what instruments are supported on different MIDI channels. In the past, Windows supported a basic/extended split of channels. Windows 95 now supports the full 16 General MIDI channels. This also means improved MIDI support in general. Windows 95 supports poly-messaging and can send multiple MIDI messages to the MIDI device—Windows version 3.x could send only one message.
The MIDI Mapper Control Panel applet is no longer needed. Users do not have to manipulate a patch map because Windows 95 takes advantage of *.IDF files created by card vendors who want to support specific patch mappings.
Windows 95 contains drivers for many of the more popular audio and video hardware devices. Driver issues, including which devices need Windows 3.1 drivers, are discussed later in this paper. Windows 95 also includes joystick support that was unavailable in the Windows version 3.1x base product.
See KB article 132992: Windows 95 Multimedia Questions and Answers
Windows 95 Multimedia Utilities
Sound Recorder—Plays and records wave audio.
Media Player—Selects and then utilizes an MCI device. MCI is a standard interface multimedia applications can use to take advantage of Windows multimedia features.
CD Player—Plays audio CDs. With minor differences, this is the same utility that ships with Windows NT. Existing CDPLAYER.INI files created with the Windows NT CD Player can be used with the Windows 95 CD Player without modification.
Volume Control—Controls sound levels on the various audio inputs. This is vendor-independent and works with all the Windows 95 sound card drivers.
See KB article 123876: Installed Components for Typical, Compact, or Portable Setup
See KB article 132623: Mixer Does Not Work After Upgrading to Windows 95
As Multimedia programs, titles, tools, and games have become more popular, consumers have begun buying add-on multimedia components, such as CD-ROM drives and sound cards. In the past installing these devices has been difficult.
Windows 95 addresses the problems associated with multimedia device installation through its implementation of Plug and Play architecture (which finds and installs Plug and Play components automatically) and the Add New Hardware wizard. Even with legacy devices, the process is easier due to the unified user interface for adding system hardware. The Add New Hardware wizard allows you to add a CD-ROM, sound, video, and game controllers. The real power of Plug and Play is that you do not need to know which IRQ, DMA, or I/O addresses to set a sound card too: it's all done automatically.
See KB article 136675: Changing SoundBlaster 16 HDMA Setting in Windows 95
See KB article 139670: Setup Does Not Detect Creative Labs Wave Blaster
The Multimedia Options in Control Panel
Having all multimedia device driver configuration settings available through Control Panel makes it easier to install and troubleshoot multimedia devices. To configure multimedia devices in Windows 95, use the Multimedia icon in Control Panel to access the Sound Systems and Multimedia icons:
System Sounds icon—Use this icon to select sound schemes, which assign sounds to system events. You can select which sounds are played for events that are registered with the system. Similar to Windows 3.1
Multimedia icon—This contains property sheets for:
Audio—Use this to select playback and recording devices. For playback area you can choose the device and select the volume level. For recording area you can select the device and sound quality (radio, telephone or CD quality) and you can customize the quality. You can also set the speaker icon to show up on the taskbar for volume adjustment.
Video—This lets you customize video playback for windowed or full screen display.
MIDI—This lets you choose a single instrument for MIDI output or create and choose a custom configuration scheme.
CD Music—Use this to select the CD device as well as the volume output for both headphones and the "line out" plug. This is also where the IDF files show up for proper MIDI support.
The Advanced Properties sheet resembles the system Device Manager. From it, you can enable and disable various devices, individualize device settings, and see what CODECs are installed.
Windows 95 includes built-in support for Audio Video Interleave playback (AVI) technology which permits the interleaving of audio and video data in one file. Video for Windows technology implements a playback scheme that keeps the audio and video synchronized while giving the best possible playback quality. Because dropped video frames are not as obvious as dropped audio frames, the playback scheme skips video frames if necessary to keep the audio smooth. Hardware also affects playback quality: a 386 system with a single speed CD-ROM drive does not play back an .AVI file as smoothly as a Pentium™ 90 with a quad-spin CD-ROM.
Compression/Decompression (CODEC) technology simplifies the compression (for storage) and decompression (for playback) of audio and video data, and this provides a major advantage to multimedia applications. Many CODEC schemes exist and some schemes are more efficient than others. Windows 95 comes with several CODECs and allows for installation of third party CODECs as well. These are discussed in more detail later.
AVI information will continue to become more important as more people surf the Internet, and now that Microsoft's Internet Explorer 2.0 supports AVIs directly in a page. The older MS Internet Explorer 1.0 from Plus! for Windows 95 does not support animation.
If you are using Internet Explorer 2.0 and it fails, go to the Iexplorer cache folder and try to play the file. If the AVI was built with a CODEC that is not installed on your system, your machine cannot play the AVI back.
If Something Goes Wrong
If a video file won't play back from a WEB page there are several things to consider. First, Windows 95 uses Media Player to play back existing video and animation files, but you can also right click on an AVI file to play directly in Explorer. If a video clip fails to play, try to play other AVI files on the system; this helps you figure out if the problem is in the application or the Windows 95 configuration. Look at the properties for the AVI file to find the cause of the problem. The format determines what CODEC (compression/decompression) is needed to play the file.
See KB article 138261: Error Message: Video Not Available, Cannot Find Decompressor
See KB article 140478: "The Road Ahead" Err Msg: Media Control Interface Error
If AVI and other multimedia files didn't use some sort of compression, an AVI file would be as much as ten times larger than its compressed version. CODEC compression differs from Drvspace because it uses lossy compression: not all the original data is in the AVI file.
Often, a great deal of the information in a video clip does not change much from frame to frame. Instead of storing all the bitmap data for each frame (an enormous amount), lossy compression stores only what changes between frames. These KEY frames contain all the bitmap data for a scene, and they can be spaced out in the AVI. If video playback becomes jerky, it usually means you are seeing only the KEY frames. They contain all the changing data for the scene, but they seem to jump when viewed one after another.
Windows 95 ships with a set of useful software-only CODECs for both video and audio, but it does not limit you to these tools. As new CODECs become available, you can add them to the multimedia subsystem by using the Add New Hardware Wizard.
Tips for AVI Troubleshooting
AVI playback depends on the video card used and the source for the AVI itself. A slow CD-ROM, for instance, might make an AVI playback jumpy by showing only KEY frames.
If you have poor AVI playback, copy the AVI file to the hard drive and see if playback speed improves. If it doesn't, see if new versions or updates are available for your current video card and driver. A lack of available RAM can also degrade playback, so try closing other running applications. If you have only 4MB, consider upgrading to 8MB.
New DirectX technology support has been added to Windows 95 to make it easier for game and multimedia application developers to create rich applications. This technology is part of the Game Software Development Kit for Windows 95. Super Bubsy, developed by ATI and published by Accolade, takes advantage of the DirectDraw graphics improvements to achieve a look very similar to its Super Nintendo and Sega Genesis counterparts.
DirectX features for Windows 95:
DirectDraw—Improves video speed by allowing direct hardware access
DirectPlay—Provides person-to-person and network games
DirectInput—Adds support for advanced joysticks and other input devices
DirectSound—Improves sound buffering and mixing capability
These features allow for a new level of great Windows games and multimedia products possible on a scale unheard of in Windows 3.x and should make for some exciting multimedia products in the future.
See KB article 139806: Err Msg: MMSYSTEM266 The Device Could Not Be Loaded
Troubleshooting Multimedia over A Network
Troubleshooting DirectPlay or other network applications is in many cases just simple network troubleshooting. Start by asking these questions:
Are both machines using the same network protocol?
Can you send a Winpopup message to the other machine?
Can both machine see each other using Netdiag?
For example, if you are using just TCP/IP on your system, the machine on the other side must also be using TCP/IP to connect. If you start Winpopup and try to send a message to the other machine and the attempt fails, you know that the application is not failing and the problem is a network issue. Netdiag, a tool that also shipped in Windows for Workgroups 3.11, is effective in isolating networking problems. Start Netdiag in an MS-DOS session on both machines and see if they can see each other. If they can, you know the network is functioning and you may need only to confirm machine names or other settings for the application to connect properly.
If that does not resolve the problem, check to see if it is related to dial-up networking or the modem itself. Some applications can use the comm port or a remote connection.
The Modem Diag Tab in Control Panel can help isolate a modem problem. If you can't communicate with the modem in the Diag Tab, turn your attention to comm port or IRQ issues. It may be necessary to install a different modem.
Some games have a sound track or play CD audio music while running. This is also true of newer business CD tutorial programs. CD Audio support requires a Redbook audio CD, which is the same format as regular audio CDs. Some newer titles even ship with a soundtrack of the music used in the program.
A typical problem is that the CD-ROM is OK, but the system does not have the right output or connection to the audio side of the CD player.
CD-ROM drives generally have a data connection for PC data and an audio connection. The audio connection can be part of a system sound card or an external patch cable running from the headphone jack on the front of the CD drive to the input jack on a sound card. One recurrent "problem" is that the audio volume simply is turned down too low. Windows 95 can have different audio levels for .WAV, MIDI, and CD audio, all of which are playing from the same CD.
See KB article Q96859: CD Audio Does Not Play Through Sound System Speakers
A new utility that comes with Windows 95, CD Player allows you to operate a CD-ROM drive as an advanced CD player with options based on a code on the CD such as random play and programmable playlist so the system remembers your favorite tracks for each disk. You can use the CD Player to troubleshoot CD audio playback problems from an application. If audio plays from a normal CD, it could be that your multimedia title is using .WAV files for the audio playback, and they sound like CD quality audio.
Sound source is hard to determine at first. The application doesn't say "play .WAV or CD Audio now". If you encounter a problem that you think is related to this, determine if the CD audio is playing from CD Player. If it is, contact the vendor to determine the type of audio being produced by the title.
Windows 95 AutoPlay starts multimedia titles automatically when you insert the disc in the CD-ROM drive. Business titles such as Microsoft Office or Plus! for Windows 95 also use the AutoPlay feature to make installation easier. If you insert an audio CD, it starts the CD Player utility and begins to play automatically.
You can bypass AutoPlay when you insert a CD by holding down the left SHIFT key.
To get AutoPlay support in Windows 95 the CD drive must be using protected-mode drivers. Use Device Manager if you are having trouble with a protected-mode driver or if you need to find out which devices are connected to a certain controller.
For protected-mode CD-ROM support, a feature called Auto Insert Notification is key to the AutoPlay functionality. In Device Manager under the CD-ROM object you'll see a checkbox to enable or disable this option.
Another issue is CD-ROM drive speed. Slow drives vary application performance based on the design of the multimedia title being played. Some still work fine at single or double speed rates. Video-intensive applications require triple or quad speed drives. Now there are even six-speed drives. Drive rates such as double, triple or quad get the data off the CD-ROM at different rates. For example a double-speed CD-ROM transfers data at about 300K/sec, about twice the rate of a single sped drive.
To help figure out how fast your drive is, some new Microsoft multimedia products include a tool called MSINFO32 version 2.5 (available soon as an appnote from electronic services such as the MS WEB site, CompuServe or MSN). You can use it to find how fast your CD-ROM is operating, how much CPU overhead it takes, and if the configuration is using protected-mode drivers or real-mode drivers.
See KB article 126025: Preventing Windows 95 from Playing Audio CDs Automatically
See KB article 131499: CD-ROM Drives Requiring Real-Mode Drivers
See KB article 131413: Testing CD-ROM Drive for File Access
Windows 95 includes built-in support for both MIDI and waveform audio (.WAV). Sound cards have generally been used for their ability to play waveform audio—the equivalent of recorded sound—which requires high amounts of disk space and CPU activity. MIDI sound uses less of these system resources.
On the Internet you run into more audio files now that Microsoft's Internet Explorer 2.0 supports them directly in a page. If audio fails when you open a page, you can sometimes figure out why it doesn't play by going to the cache folder for Internet Explorer and looking at the audio file's properties. You can also try to play the file from Sound Recorder.
If you play the Pinball game included with Plus! for Windows 95, you hear music on a MIDI track playing in the background. MIDI stands for Musical Instrument Digital Interface, a standard developed in the early 1980's by Roland® and several other keyboard companies in an attempt to standardize digital synthesizer communications.
In 1984, Apple® released the Macintosh® computer, which was the first personal computer to incorporate a built-in MIDI port for controlling external MIDI devices. The IBM PC, Atari, Commodore® 64, AMIGA, and others soon followed with add-on MIDI cards. These personal computers were the first to be used as MIDI sequencers—which control several MIDI devices and synchronize MIDI sounds to produce music.
In the latter 1980s, the Adlib® company released a MIDI synthesizer on a card for PCs and compatibles. Creative Labs, Media Vision™, Roland, and several other companies soon followed suit with cards that had external MIDI ports and synthesizers, as well as the ability to play digitized (.WAV) files on the same card.
MIDI has become increasingly popular for two reasons. First, MIDI files are extremely small because they contain only a description of how a sound should be played and not the actual sound. Second, they are portable among various computers and audio adapters.
The majority of sound cards today have on-board MIDI support. New technologies for MIDI are making it even more appealing as an alternative to .WAV for playing music within games and multimedia titles. Windows 95 includes support for enhancements such as poly-message MIDI support and 16-voice polyphony.
Windows 95 provides a MIDI tab in the Multimedia Properties dialog box for selecting settings for MIDI output. It also includes access to the Add New Instrument Wizard that walks you through adding a new MIDI instrument.
Windows 95 does not use the MIDIMAP.CFG. The Basic/Extended MIDI model requires this configuration file. With General MIDI support, you use one or more .IDF files to configure the settings for an individual instrument or device. The IDFs (generally supplied by the hardware vendor) define the patch set needed for a specific MIDI device or MIDI file. IDF is a standard, documented industry format; the MIDIMAP.CFG was undocumented and not generally accepted. Once these .IDF files are configured to the correct specifications, you need only enable or disable an instrument's individual MIDI channels in the MIDI tab. Windows 95 ships with an IDF called GENERAL.IDF.
The same MIDI device and MIDI file can sound differently due to the IDF file. If this seems to be case, contact the MIDI card vendor for assistance on IDF configuration. This is not exposed in the Windows 95 user interface.
See KB article 140501: No Sounds When Playing 3D Pinball
See KB article 138314: General MIDI Troubleshooting for Windows 95
PCs became capable of storing and playing digitized audio files in the mid 1980s. While the technology was interesting, digitized audio was primarily used by hobbyists and computer game enthusiasts. When Creative Labs released the SoundBlaster™ audio card in 1988 for the IBM PC, multimedia on IBM PCs started gaining momentum. This sound device included a MIDI synthesizer and the ability to record and playback digital audio. Digital wave audio became even more popular with Microsoft Windows version 3.1. With the introduction of OLE, it became possible to attach wave files to documents, presentations, and electronic mail messages.
Even though .WAV is CPU- and memory-intensive, there is no realistic alternative for some uses, such as voice-overs. .WAV recording and playback are supported in Windows 95 systems containing the appropriate hardware.
The Audio Tab configures installed sound cards for .WAV playback and recording. Sound card adapter configuration and installation are simplified by Plug and Play, which usually detects and configures the adapter automatically.
Compression managers compress and decompress audio file formats. (CODECs do this for AVI files.)
Use MSINFO32 version 2.5 to check out your audio system configuration. It is available on various Microsoft multimedia titles and soon will appear as an appnote on the Microsoft WEB site, MSN, and CompuServe.
If you don't have MSINFO32 version 2.5, use these questions to isolate a problem's source:
Is the problem related to other Windows applications or MS-DOS applications?
Is the system currently using a Windows 3.1 or a Windows 95 driver?
Is the problem specific to a utility shipped with the sound card?
Does sound still play from sound recorder or Media Player?
The answers can help determine if the problem is related to Windows 95 driver settings or to hardware. If you can't play a WAV sound from Sound Recorder then you know the problem is not specific to an application. If you are using an MS-DOS application with the sound card, see what the settings are. The same settings usually work with Windows 95.
You should use the Windows 95 Sound Blaster drivers only with Sound Blaster cards. Other cards, even some sold as compatible, do not always work with these drivers.
If your card is not listed in the drivers shipped with Windows 95, you need to install the Windows 3.1 drivers for the card or contact the manufacturer for Windows 95 driver support. Windows 95 is backward-compatible with the Windows 3.1 drivers, but newer drivers give better support.
Windows 95 has no drivers icon in Control Panel as did Windows 3.1. Use the Add New Hardware Wizard in manual mode.
To make sure you don't have hardware conflicts in Device Manager, try other multimedia applications or Windows 95 tools to focus in on the cause of the problem. Many Windows 3.1 users simply configured the Sound Blaster driver for their different cards; in Windows 95, you must have appropriate driver support for your card.
See KB article 133365: Troubleshooting Problems with Compressed Audio
See KB article 140334: Troubleshooting Wave Sound File Problems in Windows 95
See KB article 130613: Audio, MIDI, Capture Cards Requiring Windows 3.1 Drivers
See KB article 138857: How to Install and Use the PC Speaker Driver with Windows 95
Joystick Installation Issues and Missing Ports
Some joystick installation problems can be cleared up by supplying needed Windows 3.1 drivers. Other problems may be more difficult to isolate and solve. Because joystick support is new, here is some information on usability and configuration.
Suppose, for instance, the joystick can't control the mouse cursor. How can you test the joystick to see if it works in Windows 95? If you have a game that was designed for Windows 95 and supports a joystick, there is an application in Control Panel that allows you to calibrate the joystick. Here is how the application works when troubleshooting the new Microsoft Sidewinder 3D Pro joystick.
To get to the application, choose the Start button, choose Settings and then Control Panel.
Double click on the Joystick applet.
In the Joystick Configuration section use the scroll bar to select the Joystick type.
Click on the Calibrate button.
You'll then be asked to complete a series of tests depending on the capabilities of the joystick. For example, the sidewinder can calibrate the joystick, the throttle, the rudder and the POV hat.
When you're done, a button is provided for testing the calibration.
Particular types of joysticks do not have common installation issues, but there are two issues worth noting:
If you add a joystick when you already have a sound card set up, the Add New Hardware Wizard cannot detect the Joystick until you remove the sound card driver.
If you have a joystick installed and configured correctly and you remove the sound card, the joystick is not removed along with it.
See KB article 132517: Joystick Port Not Removed When Sound Card Is Removed
See KB article 138082: Game Port Not Detected with Sound Card Already Installed
Windows 3.1 Drivers Needed
Support call volumes suggest that Multimedia is a major user concern. Most calls seem to be on device configuration and driver installation. How do you get Multimedia devices such as sound cards and CD-ROM drives working correctly?
First, check if there is a protected mode Windows 95 driver for the device.
You also need to know whether the sound card supports 8-bit or 16-bit DMA (Direct Memory Access). If the sound card supports only one and you have it configured for the other, you may hear static when playing .WAV files. Switch to a different DMA channel to get rid of the static
DMA channels 0 through 3 are 8-bit, channels 5 through 7 are 16-bit. Here is how to change the DMA channel.
Open the System Property Sheet by clicking on Start and Settings and then Control Panel
Double-click on the System Icon
Click on the Device Manager tab
Expand the list of Sound, Video, and Game controllers
Double-click on the driver for the sound card to bring up its property sheet or Highlight the driver and choose the Properties button.
Choose the Resources Tab
Find the DMA channel and remove the check from the Use Automatic Settings box.
Click on the Change Setting button
This allows you to choose one of the available 8-bit or 16-bit channels.
See KB article 130613: Audio, MIDI, Capture Cards Requiring Windows 3.1 Drivers
See KB article 131499: CD-ROM Drives Requiring Real-Mode Drivers
See KB article 127022: 16-Bit DMA May Cause Static or System Hang
CD-ROM Drives That Don't Follow ATAPI 1.2
Microsoft protected-mode drivers follow the ATAPI 1.2 specification. If you insert an audio CD and the CD-ROM drive light starts blinking but you don't get any music, it often is because the drive does not follow this spec. Sometimes you get an error message such as "Data or no disc loaded. Please insert an audio compact disc."
ATAPI says that track 1 on the CD is supposed to start at the 2-second mark. When the driver doesn't find the beginning of track 1 at the 2-second mark, the driver tries over and over to find track 1, which is why it appears that the drive is reading the CD.
There are several workarounds for this:
Contact the manufacturer for the CD-ROM drive to see if a firmware revision is available for the drive to bring the drive into compliance with the ATAPI 1.2 specification.
Remove the protected mode drivers for the CD-ROM drive and reinstall the Windows 3.1 drivers
Check with the manufacture for an updated Windows 95 driver that can support your drive.
See KB article 137310: Audio CD Not Recognized in IDE CD-ROM Drive
Windows 95 is a solid multimedia platform. It includes support for .WAV, MIDI, improved video, and joysticks, and is backwards-compatible with Windows 3.x drivers. Also helpful is the MSINFO32 (version 2.5) utility, which you can use to test various multimedia features. As always, the Knowledge Base is the best source of information for troubleshooting or just learning more about multimedia and Windows 95.
This article was derived from a Microsoft Traincast session. If you are interested in other Traincast offerings, call 1-800-597-3200 or e-mail firstname.lastname@example.org.
Volume 4, Issue 2