If you have embedded a video clip into your PowerPoint presentation from a file, the video will appear at whatever random frame it begins with when it is first seen by your audience. To make things look better, you can add a poster frame in place of the first video frame. You have two choices: 1) in edit mode play into the video until you find a frame from the video that you like and make that the poster frame (i.e., the one your audience will see in place of the first frame of the video); 2) create a graphic to be the poster frame. Here’s how:
Select a frame from the video.
After the video is embedded on your slide, and sized to the desirable dimensions, click the play button until you find a frame you like. Stop the video on that frame. With the video selected click on the Video Tools tab, its sub-tab labelled Format, and click the drop-down under Poster Frame. Choose Current Frame. This will become the poster frame your audience will see in place of the first frame of the video.
Create a graphic of your own.
A more elegant solution would be to create a graphic in the exact size of the video window to serve as the poster frame. First, select the video, click on Video Tools and Format. Look to the right of the ribbon and you will see the height and width dimensions for the video window. In my example, I have resized the video window to a non-standard size.
In the Slides side-panel click beneath the slide containing your video, and then click the New Slide icon on the Home tab. If necessary, change the slide layout to be a blank slide. This is just a temporary place for you to create your graphic. We will be deleting in when we are done. Now, draw a rectangle larger than your video window: Click the Insert tab, click the drop-down under Shapes and select the rectangle tool.
Select the rectangle you have drawn. The Drawing Tools tab will appear at the top of the screen. Click it, click the format tab, and change the Height/Width dimensions to match those of your video window. Now you have a rectangle exactly the same dimensions as your video window. It has a fill color and line color, which can be formatted to anything you wish. A quick way to format it is to use the Shape Styles on the Drawing Tools tab to add a gradient fill, type a title, make the title nice and big, and format the title with the WordArt Styles, also on the Drawing Tools tab. Now here is the trick: select the object you have just created and formatted, right-click it, and choose Save as Picture…
Save it somewhere you can find it again. Now you can delete this “work slide.” You have the picture you want to use as your poster frame.
Return to the slide that contains you video, select it, click on Video Tools > Format, click the drop-down under Poster Frame and choose Image from File…
Navigate to the picture you just saved and select it and click Insert. It will become the frame your audience first sees.
A cool effect.
An effect that will really give your video a professional look is to once again, select your video after you have inserted the new poster frame. On the Video Tools > Playback tab in the Editing group increase the Fade In Fade Duration time to about 2 seconds.
Now test your video in Slideshow mode. The poster frame will appear in the video window. When you click play the poster frame will gradually fade away into the video itself, while the soundtrack plays all the time.