PowerPoint and Multimedia - Part III

< Continued from Page 2

Codecs Are A Must
Bringing It Altogether
Alternative Methods
Portability of Presentations
Closing Remarks

Codecs Are a Must - Find Them Here

What the heck is a codec, and why do you need them? Codec stands for Compressor/Decompressor and it does pretty much what the name implies. Codecs are used to compress multimedia files for transfer and storage, and then to reverse the process for playback. If you have ever used the ZIP file format to compress a file, you have the general idea.

Why are there so many different codecs? Different forms of multimedia compress very differently depending upon their contents. Consider the difference in the sound of a car engine running and a full orchestra playing music. The engines sound is of a very low frequency and repetitive, while the orchestra produces a full frequency of sound with little repetition. Obviously the engine sound would compress much differently than would the orchestra music. So we use a different tool or codec to get the job done. The same analogy holds true for video. Codecs are constantly being upgraded and the technology envelope is being pushed to compress the file smaller without losing quality during playback.

The good news is that Microsoft foresaw the need for future codecs and built the MCI so we can simply install them as needed. In plain terms, a codec is just another module of the MCI and the MCI makes it available to other software, in our case, PowerPoint.

There are literally hundreds (thousands?) of codecs in use today and no one would have all of them installed on their machine. However there are the "common" ones that should be on every machine. In order to determine which codecs are install on your machine go into Control Panel and double click Multimedia. Click on the Devices Tab and look for Audio Compression Codecs and Video Compression Codecs. Click on either of these to see a list of the codecs installed. Here is a list of some of the most common codecs:

DSP Group
TrueSpeech Software Audio Codec 

Intel 
Indeo R3.1 Video Codec
Indeo R3.2 Video Codec
Indeo 5.04 Video Codec

Microsoft Audio Codices
ADPCM Audio Codec
CCITT G.711 A-Law and u-Law Audio Codec
GSM 6.10 Audio Codec
IMA ADPCM Audio Codec

Microsoft Video Codices
RLE Video Codec
Video 1 Video Codec

SuperMatch
Cinepak Video Codec

Fraunhofer
Fraunhofer IIS MPEG Layer-3 Codec

In putting this information together I have tried to track down sites where codecs could be downloaded. I found two things: First, folks that create codecs tend to play it very close to the chest. That is you won’t find much in the way of web sites that have lots of them for down load. And second, the companies change the URLs to their sites on a regular basis so placing them in this document is a waste of time. So the best advice I can give is to use your favorite search engine and go hunting on the web.

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It Bringing Altogether

OK, we have the WIN.INI and SYSTEM.INI files straightened out, and we have the standard codecs installed, now what? Next come driver issues. The most common problem I've seen in multimedia and PowerPoint is problems in the video drivers.

If you are experiencing a situation where PowerPoint allows you to insert the multimedia file but it doesn't play as expected the chances are it's a video problem. What can be done about it? Before "fixing" the problem lets try to determine that it is in fact a video problem. To do this, restart your computer in Safe Mode and run the presentation. It won't be pretty but the question to be answered is, did it play properly? If the answer is yes then it's almost certain you have a video driver issue. There are three basic "fixes" for this situation.

First, go to the web site of your video card manufacturer and see if there is an updated driver for it. If you aren't certain which driver to use, most manufactures provide a small utility to examine your system and give you this information. You might also be able to get this information from Control Panel - System - Device Manager. Look for "Display Adapter".

Second, change your display color depth. I wish I had a magic formula to tell you which optional setting to use but it depends upon your particular system. So, simply try different settings to see if one works properly when you play your presentation.

T hird, Lower your video hardware acceleration. Again go into Control Panel - System - Performance. You will see a button labeled "Graphics". Click it and you are presented with a slide control, which may be used to set the acceleration level. Move it down one "notch" at a time and try the presentation.

One or a combination of these things should fix the problem. However, I will note that I have run into problems with certain new video cards that I wasn't able to resolve. The answer at that point was to replace the video card. As a side note, many of the video cards that have video capture or "video in" tend to install their own proprietary codecs. These will work fine on your machine but if you move the file to another machine it may not work at all. Just a word to the wise.

These same issues are applicable to sound playback. First make certain the WIN.INI and SYSTEM.INI files are correct, then make certain the required codecs are in place, and then play the file in "mplayer.exe" (mplayer32.exe for winNT). If you are unable to play the sound in this manner there are problems with your sound subsystem.

The fixes are the same as for video issues. Make certain you have the latest driver for your sound card from the manufacture. Next make certain your playback settings match or exceed the quality level of your file. As an example, if you have your system set to produce only 8-bit mono playback and the file is 16-bit stereo the quality of the sound will obviously suffer, or may not play at all. And the last area to look at is the audio hardware acceleration. Again try adjusting it gradually and try playing the presentation after each adjustment.

All the audio adjustments are made in Control Panel | Multimedia | Audio.

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Alternative Methods

Up to this point we have been dealing with how to play multimedia "natively" in PowerPoint. By that I mean using the standard method of, Insert | Sound/Movie | From File. There are a number of other ways to do this, and the following are some examples.

If you use "drag and drop" to place a multimedia file on a slide, an instance of "Windows Media Player" is created. At that point Media Player is in control of the playback.

To play a non-supported file format (QuickTime, Real Media,) you may Insert - Object - Create From File and navigate to the file and insert it. This will call the player that is associated with that file type. This of course assumes you have the correct player installed on your system.

You may also hyperlink to the file. Select the object or text you want to assign the hyperlink to, and Insert - Hyperlink. In the "Link To" window select Existing File or Web Page, and then navigate to the desired file. Again the player associated with the file type will be called. I happen to like using this method when giving a presentation because it allows me to have control of when the movie is played.

There are a number of additional methods to play multimedia in PowerPoint using Visual Basic for Applications, Active X controls, or Visual Basic controls already existing in PowerPoint. However, they are well beyond the scope of this document and are best left to the programmer types.

There is one last method that I should mention. If you have an OLE compliant application, it to may be inserted as an Object. One place this might come in handy is the playback of DVD movies. Neither PowerPoint nor Windows Media Player is equipped to handle this format.

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Of Portability Presentations

I've included this section as many users ask why their presentation works on one machine and not another. As you can see from all the above information it isn't so much a PowerPoint problem as it is an environment (Windows Setup) problem. We simply have no way of knowing in advance how the receiving user has his/her machine setup.

What can be done to maximize success in transporting presentations?

Don't create a presentation with critical timing on a fast machine and expect it to work the same way on lesser machines. If you have a video playing, don't add to the computers workload by having other animations happening at the same time. It's also a good practice to place a couple of seconds between slide transitions and the start of a video.

Use Multimedia file formats that are likely to be found on most machines. For video this is the AVI format using the Cinepak codec or the (preferred) MPEG format. For audio use the Microsoft wav format. I can hear the grumbling already about quality and file size. Folks, if you want to distribute the presentation to others you have to use the lowest common denominator. Remember, a big file that plays properly is a lot better than a small file that doesn't play at all.

Be certain that you include any multimedia files along with the presentation. Because Microsoft uses the word "Insert" we tend to think the file has been inserted into the presentation. Unfortunately this isn't true, the Multimedia file has been "linked" to the presentation and it is called when needed. PowerPoint expects to find the file in the same place it was originally linked from.

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Closing Remarks

That about covers the "generic" information on using PowerPoint and multimedia. I'm certain there are a number of issues that are specific to your machine and presentation, but I couldn't possibly cover all of them in this document.

If you have read through this information, made the suggested changes, and still encounter problems or issues, we urge you to visit the PowerPoint newsgroup (link no longer exists), where a bunch of wonderful folks spend time together to get the most out of PowerPoint.

Heck, don't wait until you have problems, just stop in and say hello. You never know what you might learn or teach others.

Happy Presentations,

Austin Myers
Microsoft PowerPoint MVP

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