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5.3
Replace Videos by Series of Still Images
The safest option, when planning on showing videos, is to replace them by a series
of still images which you can animate yourself within your slide presentation
software.
Of course, this will not be practical for movies that last more than a few seconds,
or when sound is important, or when smooth flow of images is critical. But if you
are dealing with a short silent movie (for instance a high-speed movie from an
experimental trial) or if you display computer-generated animations, replacing videos by a series of still images is either a very good Plan-B, or can actually replace
the video altogether as your Plan-A.
There exist a few options to extract still images from a video. One of them is to
use an advanced video editing software which includes this feature (follow the
software- specific instructions to turn videos into a series of images).
Another option is simply to rely on screen captures of video frames:
• Play the video in full screen mode using any available video software
• You might press “pause” at the exact frame you want to extract (optional)
• Hit the “Print Screen” button (Sect. 4.5) – paste the image in your slide, remove
areas around the image (cropping)
– Redo the operation until you have all the frames you need
The number of frames you need really depends on what you want to show, and
how fast the images change over time. In some cases, 5 frames might be sufficient,
while in other cases, many more frames might be needed (which can make this
technique not so practical).
You can put each individual video frame in a separate slide (Option 1 animation,
Sect. 3.2), ensuring that the resulting images are always positioned at the exact same
place (Sect. 3.6). Or, alternatively, if you only have a few frames, you could superimpose them on a single slide, and use the software animation tools (Option 2 animation, Sect. 3.3).
Advantages:
• Avoid the very frequent potential technical issues with videos
• Play the “video” at the pace you want, easily stopping whenever you want, and
easily back tracking
• Set the animations to be automatic (e.g. an image per second)
• Include markers, text, arrows, etc. on any single frame
• Show frames that are not equally spaced in time (flexibility!)
• Individually correct resulting images (removing unwanted elements from the
frames, enhancing image quality, etc.)
• Zoom in easily
• Save memory space
5 Videos
5.3
Replace Videos by Series of Still Images
The safest option, when planning on showing videos, is to replace them by a series
of still images which you can animate yourself within your slide presentation
software.
Of course, this will not be practical for movies that last more than a few seconds,
or when sound is important, or when smooth flow of images is critical. But if you
are dealing with a short silent movie (for instance a high-speed movie from an
experimental trial) or if you display computer-generated animations, replacing videos by a series of still images is either a very good Plan-B, or can actually replace
the video altogether as your Plan-A.
There exist a few options to extract still images from a video. One of them is to
use an advanced video editing software which includes this feature (follow the
software- specific instructions to turn videos into a series of images).
Another option is simply to rely on screen captures of video frames:
• Play the video in full screen mode using any available video software
• You might press “pause” at the exact frame you want to extract (optional)
• Hit the “Print Screen” button (Sect. 4.5) – paste the image in your slide, remove
areas around the image (cropping)
– Redo the operation until you have all the frames you need
The number of frames you need really depends on what you want to show, and
how fast the images change over time. In some cases, 5 frames might be sufficient,
while in other cases, many more frames might be needed (which can make this
technique not so practical).
You can put each individual video frame in a separate slide (Option 1 animation,
Sect. 3.2), ensuring that the resulting images are always positioned at the exact same
place (Sect. 3.6). Or, alternatively, if you only have a few frames, you could superimpose them on a single slide, and use the software animation tools (Option 2 animation, Sect. 3.3).
Advantages:
• Avoid the very frequent potential technical issues with videos
• Play the “video” at the pace you want, easily stopping whenever you want, and
easily back tracking
• Set the animations to be automatic (e.g. an image per second)
• Include markers, text, arrows, etc. on any single frame
• Show frames that are not equally spaced in time (flexibility!)
• Individually correct resulting images (removing unwanted elements from the
frames, enhancing image quality, etc.)
• Zoom in easily
• Save memory space
5 Videos