Difference between revisions of "How to Put Video Files in presentations"

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<h2>Introduction</h2>
<h2>Introduction</h2>


<p>You’ve probably heard the saying that “a picture is worth 1000 words�?. If
<p>You've probably heard the saying that "a picture is worth 1000 words". If
this is true, a movie is probably worth even more. Putting a video file into a
this is true, a movie is probably worth even more. Putting a video file into a
PowerPoint presentation can be a very effective way of showing a concept.
PowerPoint presentation can be a very effective way of showing a concept.
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<p>This part of the task is easy. You can insert it as an object. Go to the menu
<p>This part of the task is easy. You can insert it as an object. Go to the menu
at the top and select “Insert�?. On the pull down menu that appears, select
at the top and select "Insert". On the pull down menu that appears, select
“Movies and Sounds�?. On the next menu that appears, select “Movie from File�?. A
"Movies and Sounds". On the next menu that appears, select "Movie from File". A
dialog box will appear prompting you for the file to insert. First, navigate to
dialog box will appear prompting you for the file to insert. First, navigate to
the directory where your video is, then select it from the list of files, and
the directory where your video is, then select it from the list of files, and
click “Open�? to put it into your presentation.</p>
click "Open" to put it into your presentation.</p>


<p>To confirm that you’ve selected the proper file, PowerPoint will show the
<p>To confirm that you've selected the proper file, PowerPoint will show the
first frame in the movie, its start.</p>
first frame in the movie, its start.</p>


<p>You’re done! It’s that easy!</p>
<p>You're done! It's that easy!</p>


<h3>Microsoft Office PowerPoint 2007</h3>
<h3>Microsoft Office PowerPoint 2007</h3>
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<b><i>Media Clips</i></b> group. A dialog box will appear prompting you for the
<b><i>Media Clips</i></b> group. A dialog box will appear prompting you for the
file to insert. First, navigate to the directory where your video is, then
file to insert. First, navigate to the directory where your video is, then
select it from the list of files, and click “Open�? to put it into your
select it from the list of files, and click "Open" to put it into your
presentation.</p>
presentation.</p>


<p>To confirm that you’ve selected the proper file, PowerPoint will show the
<p>To confirm that you've selected the proper file, PowerPoint will show the
first frame in the movie.</p>
first frame in the movie.</p>


<p>You’re done! It’s that easy!</p>
<p>You're done! It's that easy!</p>


<h2>Things to consider</h2>
<h2>Things to consider</h2>
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<p>Videos are very large files. Adding a video to your presentation will
<p>Videos are very large files. Adding a video to your presentation will
probably significantly increase how long it takes to transmit and open the
probably significantly increase how long it takes to transmit and open the
presentation. Also, if you’re submitting the presentation to an online
presentation. Also, if you're submitting the presentation to an online
submission facility such as the MyPoly Digital Dropbox or the EG1004 Web site,
submission facility such as the MyPoly Digital Dropbox or the EG1004 Web site,
your presentation may exceed the limit on file size the site will accept.</p>
your presentation may exceed the limit on file size the site will accept.</p>
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to submit both the presentation and the video file. One way to do this would be
to submit both the presentation and the video file. One way to do this would be
to put both items in a ZIP or RAR file. You can learn how to do this by looking
to put both items in a ZIP or RAR file. You can learn how to do this by looking
at the instructional Web page “How to Compress Your Files�? in the “Instructional
at the instructional Web page "How to Compress Your Files" in the "Instructional
Web Pages�? section of this manual. After you’ve created this file, you can
Web Pages" section of this manual. After you've created this file, you can
submit it to the online submission facility, but check with your teacher first
submit it to the online submission facility, but check with your teacher first
to make sure that this form will be acceptable.</p>
to make sure that this form will be acceptable.</p>


<p>If you don’t do this, or the online submission fails, you’ll only see the  
<p>If you don't do this, or the online submission fails, you'll only see the  
opening frame, not the entire video.</p>
opening frame, not the entire video.</p>


<h3>Chroma key</h3>
<h3>Chroma key</h3>


<p>To understand the next issue, we’ll have to digress and talk about how
<p>To understand the next issue, we'll have to digress and talk about how
television and movies work. We’ve all seen special effects where an actor seems
television and movies work. We've all seen special effects where an actor seems
to be walking on thin air, jumping from a high place with no visible means of
to be walking on thin air, jumping from a high place with no visible means of
support, being thrown by an explosion, etc. Scenes like this are actually shot
support, being thrown by an explosion, etc. Scenes like this are actually shot
as two separate scenes (the actor and the background) and then combined.
as two separate scenes (the actor and the background) and then combined.
Similarly, the nightly weather report seems to be given by a person standing in
Similarly, the nightly weather report seems to be given by a person standing in
front of a map or tabular data. Like the movie, this isn’t really happening;
front of a map or tabular data. Like the movie, this isn't really happening;
their video picture is being combined with a second video that is typically
their video picture is being combined with a second video that is typically
computer generated.</p>
computer generated.</p>
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done photographically, but these days it is more likely to be done using  
done photographically, but these days it is more likely to be done using  
computers. For videos, it is almost always done by computers. This is why, in
computers. For videos, it is almost always done by computers. This is why, in
a movie, the person in the action doesn’t wear anything that’s bright blue – it
a movie, the person in the action doesn't wear anything that's bright blue – it
would be too close to the chroma key and make the person transparent, like a
would be too close to the chroma key and make the person transparent, like a
ghost. (In fact, this is how movies make ghosts or body parts move around – the
ghost. (In fact, this is how movies make ghosts or body parts move around – the
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Similarly, on television, the weather person is standing in front of a green
Similarly, on television, the weather person is standing in front of a green
wall (the chroma key) and is careful not to wear anything bright green (even on
wall (the chroma key) and is careful not to wear anything bright green (even on
St. Patrick’s Day). Occasionally you’ll see people who forget this, and parts of
St. Patrick's Day). Occasionally you'll see people who forget this, and parts of
them turn transparent.</p>
them turn transparent.</p>


<p>Why were these colors chosen? In both cases they were chosen because human
<p>Why were these colors chosen? In both cases they were chosen because human
flesh doesn’t contain these colors, insuring that they’ll look good in when the
flesh doesn't contain these colors, insuring that they'll look good in when the
shots are combined. Why did movies and video choose different chroma key colors?
shots are combined. Why did movies and video choose different chroma key colors?
Movies came first, and it was relatively easy to make large areas of Cadmium
Movies came first, and it was relatively easy to make large areas of Cadmium
Blue. Television signals use green to show shades of gray on black and white TV.
Blue. Television signals use green to show shades of gray on black and white TV.
In both cases the color is a very sharp point in the color spectrum. Any further
In both cases the color is a very sharp point in the color spectrum. Any further
discussion is beyond the scope of this page. However, it’s easy to find
discussion is beyond the scope of this page. However, it's easy to find
additional information using any Internet search engine with the term “chroma
additional information using any Internet search engine with the term "chroma
key�?.</p>
key".</p>


<p>One note: during the making of the Star Trek television series and movies, it
<p>One note: during the making of the Star Trek television series and movies, it
was very difficult to have space aliens in some scenes because their “flesh�?
was very difficult to have space aliens in some scenes because their "flesh"
contained significant components of the chroma key color, causing the scene to
contained significant components of the chroma key color, causing the scene to
look wrong. Also, if you’re wondering how the weather person is able to point to
look wrong. Also, if you're wondering how the weather person is able to point to
things on the maps, they’re actually looking at a television monitor showing
things on the maps, they're actually looking at a television monitor showing
what’s being transmitted, and moving their hand to the right place in the
what's being transmitted, and moving their hand to the right place in the
combined image.</p>
combined image.</p>


Line 122: Line 122:
video, it makes a chroma key frame behind your video. In this case your computer
video, it makes a chroma key frame behind your video. In this case your computer
is not shooting the video, but is showing it, so the chroma key color used is
is not shooting the video, but is showing it, so the chroma key color used is
black (when you’re displaying something adding black to it doesn’t change it).
black (when you're displaying something adding black to it doesn't change it).
If you’re using a computer that’s using multiple video ports (for example, a
If you're using a computer that's using multiple video ports (for example, a
laptop that’s showing the presentation on its LCD screen and also on a video
laptop that's showing the presentation on its LCD screen and also on a video
projector), occasionally the video circuitry will not work properly, and all
projector), occasionally the video circuitry will not work properly, and all
you’ll see is a black frame on one or both screens. This is the chroma key
you'll see is a black frame on one or both screens. This is the chroma key
without the video being overlaid on it properly.</p>
without the video being overlaid on it properly.</p>



Revision as of 03:08, 23 January 2009

How to Put Video Files in Presentations

Introduction

You've probably heard the saying that "a picture is worth 1000 words". If this is true, a movie is probably worth even more. Putting a video file into a PowerPoint presentation can be a very effective way of showing a concept. However, you have to be careful to do it correctly, and also be aware of some of the pitfalls that can happen when using video files.

Including the video file

Microsoft Office PowerPoint 2003

This part of the task is easy. You can insert it as an object. Go to the menu at the top and select "Insert". On the pull down menu that appears, select "Movies and Sounds". On the next menu that appears, select "Movie from File". A dialog box will appear prompting you for the file to insert. First, navigate to the directory where your video is, then select it from the list of files, and click "Open" to put it into your presentation.

To confirm that you've selected the proper file, PowerPoint will show the first frame in the movie, its start.

You're done! It's that easy!

Microsoft Office PowerPoint 2007

This part of the task is easy. Click on the Insert tab on the ribbon. On the new ribbon, click on the Movie icon in the Media Clips group. A dialog box will appear prompting you for the file to insert. First, navigate to the directory where your video is, then select it from the list of files, and click "Open" to put it into your presentation.

To confirm that you've selected the proper file, PowerPoint will show the first frame in the movie.

You're done! It's that easy!

Things to consider

Before you actually include a video, there are a number of items you should consider.

File size

Videos are very large files. Adding a video to your presentation will probably significantly increase how long it takes to transmit and open the presentation. Also, if you're submitting the presentation to an online submission facility such as the MyPoly Digital Dropbox or the EG1004 Web site, your presentation may exceed the limit on file size the site will accept.

Links between the presentation and the video

PowerPoint handles videos differently than it does other objects that are included in the presentation. A complete description of how PowerPoint works is beyond the scope of this document. However, an easy way to avoid these issues is to have the video in the same directory as your presentation. This means you may have to move the video to the proper directory BEFORE including it in the presentation. Second, when submitting to an online submission facility, be sure to submit both the presentation and the video file. One way to do this would be to put both items in a ZIP or RAR file. You can learn how to do this by looking at the instructional Web page "How to Compress Your Files" in the "Instructional Web Pages" section of this manual. After you've created this file, you can submit it to the online submission facility, but check with your teacher first to make sure that this form will be acceptable.

If you don't do this, or the online submission fails, you'll only see the opening frame, not the entire video.

Chroma key

To understand the next issue, we'll have to digress and talk about how television and movies work. We've all seen special effects where an actor seems to be walking on thin air, jumping from a high place with no visible means of support, being thrown by an explosion, etc. Scenes like this are actually shot as two separate scenes (the actor and the background) and then combined. Similarly, the nightly weather report seems to be given by a person standing in front of a map or tabular data. Like the movie, this isn't really happening; their video picture is being combined with a second video that is typically computer generated.

In all these cases, the person is moving or standing in front of a wall consisting of a single color. Historically, this has been called a chroma key. For movies, this wall is typically an intense bright blue called Cadmium Blue, named after the spectral signature of the element Cadmium. For video work, the person is typically standing in front of a bright green wall. In both cases, the background is shot normally. Now the two pictures are combined. For the first picture (the person), all colors other than the chroma key are overlaid on the second picture, and the chroma key color is ignored. For movies, this has been done photographically, but these days it is more likely to be done using computers. For videos, it is almost always done by computers. This is why, in a movie, the person in the action doesn't wear anything that's bright blue – it would be too close to the chroma key and make the person transparent, like a ghost. (In fact, this is how movies make ghosts or body parts move around – the actor wears a chroma key bag on the parts that should be transparent.) Similarly, on television, the weather person is standing in front of a green wall (the chroma key) and is careful not to wear anything bright green (even on St. Patrick's Day). Occasionally you'll see people who forget this, and parts of them turn transparent.

Why were these colors chosen? In both cases they were chosen because human flesh doesn't contain these colors, insuring that they'll look good in when the shots are combined. Why did movies and video choose different chroma key colors? Movies came first, and it was relatively easy to make large areas of Cadmium Blue. Television signals use green to show shades of gray on black and white TV. In both cases the color is a very sharp point in the color spectrum. Any further discussion is beyond the scope of this page. However, it's easy to find additional information using any Internet search engine with the term "chroma key".

One note: during the making of the Star Trek television series and movies, it was very difficult to have space aliens in some scenes because their "flesh" contained significant components of the chroma key color, causing the scene to look wrong. Also, if you're wondering how the weather person is able to point to things on the maps, they're actually looking at a television monitor showing what's being transmitted, and moving their hand to the right place in the combined image.

Why is knowing about chroma key important? When PowerPoint includes your video, it makes a chroma key frame behind your video. In this case your computer is not shooting the video, but is showing it, so the chroma key color used is black (when you're displaying something adding black to it doesn't change it). If you're using a computer that's using multiple video ports (for example, a laptop that's showing the presentation on its LCD screen and also on a video projector), occasionally the video circuitry will not work properly, and all you'll see is a black frame on one or both screens. This is the chroma key without the video being overlaid on it properly.

Summary

Adding video to a presentation can make it much more interesting. If you are aware of the dangers involved in including it, you can include your video with confidence, and make a better presentation. However, ignoring these issues can lead to frustration.