Wednesday, August 20, 2008

Before You Play Back Audio or Video from Your Laptop Computer...

Compression looks bad and sounds bad when the file is too small! When you blow it up, it is terrible. If you don't prepare your AV content for playback, there may be a time-lag before your media player shows on a screen. This is not always because of a mis-match of projectors, in fact, I've used two matched projectors, bought at the same time and one of them had a four second delay before the image was shown. So, one screen will show and the second follows with a time lag.

I've done this in a room full of AV professionals and not one of them could give me a definitive answer on this, so much more troubleshooting and research must be done by me in order to find out why this happens with a matched pair. I could read specs until I'm blue in the face, but there still has to be a workaround before this does occur to make the presentation look professional - see below.

If you play a DVD from your computer, make sure it plays back smoothly. Not all DVD players on computers behave properly 100% of the time. If they did, I would never hear: "Well, it should work." or "Well, it worked last night." because those words don't help much when 200 people are staring at the screens, expecting to see and hear something; they'll soon start to look at the presenter. This type of problem can be easily corrected and I'd love to help out.

With these things in mind, check these tips out:

COMPRESSED AUDIO and VIDEO PLAYED BACK LIVE:
If it's a video played for humor, who cares if it's perfect. If it's a sample of advertising or the newest content for the Out-of-Home media industry, it has to play back well. So, I'd suggest having an uncompressed digital file on a DVD-R or +R (data DVD), but not a DVD-RW (they are not as compatible). That way, the file simply needs to be dragged and dropped onto a host computer and will play back smoothly.

If you have your own laptop, even better - BUT, you must set the audio to have the proper gain structure! As a rule of thumb, set your .wav volume to 75% and you master volume to between 50% and 75% (cranking the .wav volume can distort, depending on your sound card - I wish there were more of a standard!).

If you embed a file into PowerPoint, you may have to change the 'file size limitation' setting to allow your .avi to be played back from within PowerPoint. There is no better way to test this than to run it through the equipment you will be using the day of your presentation.

IMPROPERLY PREPARED AUDIO-VISUAL PLAYED BACK LIVE:
Always have a selection of video formats to play back from on a series of data DVD's. DVD's do not take up much room. Carry a 2.5" portable hard drive with various formats on it and you probably can't go wrong. I have sat and edited video and audio, last minute, for many presenters, burned a quick DVD and got it running for them - but, what if you don't have the proper AV support?

Also, be sure that your edited video has a four second time delay before it (a blank screen) to avoid a time-lag before you see the video - the audio will play but the first four seconds of the video can be cut off.

DVD PLAYBACK ISSUES FROM A LAPTOP.
If you have your own laptop to play back from, ensure the settings match the projector's native settings (at the moment, 1024x768 is the norm) because the projector may go out of sync or the image won't fill the screen.

Also, be sure there are no issues with wireless connections 'searching', anti-virus software interrupting or chat boxes opening up during the show.

Bottom line - until all computers and projectors get along in the real world (not the product literature world), AV presentations must be checked and double checked through the exact equipment which will be used on the day of a presentation.

AV issues? I can help!

Buck Moore
Live Event AV Specialist
Public Speaker

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