Video

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PowerPoint

MS PowerPoint is extremely picky with files. If you need to include a video in a presentation that will be shared with others, we suggest using an animated GIF. While this will produce relatively large files, it should be playable on most copies of PowerPoint on most platforms without modification. Furthermore, the movie will actually be embedded, which means that you won't have to worry about broken links when the presentation is moved.

When you insert an animated gif, insert it as an image (not as a movie). The animation will still work & this is a more robust method of having the image embedded in the presentation file and working across platforms.

Alternatively, MPEG-1 works most places & can make smaller files. However, one must be careful not to break the links between the movie file and the presentation (one should "pack" the presentation & then not rename or move the files). Due to these limitations David Seidman very much prefers GIFs.

Outside of these two formats, support will be based on which codecs are available. Default codecs vary between OSs & installed codecs vary between computers.

Windows usually has the Intel/Indeo codecs, the MS RLE and wmv1 codecs, and the Cinepak codec. All of these are used in AVI containers.

Mac usually uses the codecs provided by QuickTime.

It is strongly advised that you upgrade your copy of PowerPoint to play more codecs. To do this on windows, consider installing:

Both are free and open source. The former will let you play:

  • XVID
  • DivX 3,4,5
  • MS MPEG4 1,2,3
  • WMV 1(7),2(8)
  • 3IV2,3IVX,RMP4,DM4V
  • MPEG 1,2
  • H.263
  • H.264, X.264
  • MJPEG
  • DV
  • HuffYUV
  • CorePNG, MPNG
  • RAW

in any container format. The later will let you use MP4 containers. These make up a majority of the commonly used formats.

You can test whether your copy of PowerPoint will play a file by using 'mplay32'. Due to the brain-dead file detection windows uses, you will find that if you rename your file to have a 'wmv' extension (instead of an 'avi' or 'mp4' extension), it will be more likely to work.

Conversion

For out-of-the-box compatibility, choose MPG or GIF. For small filesize (with good quality) & ability to use on any platform (after installing needed software), including the video iPoid, choose MP4 with H.264.

GUI

GraphicConverter

GraphicConverter is a commercial and proprietary application for Mac OS. NUCAPT has a copy on many of the Macs that we use. GraphicConverter can put together frames to a movie, at least animated gif, if you go to the File->Convert dialog and check the movie option in the options dialogue:

Other programs

  • Avidemux - F/OSS for any OS (typically AVI, but also OGM, MP4, and MPG)
  • MeGUI - F/OSS for win32 (typically H.264 (especially in MP4, but also in AVI)
  • VirtualDub, VirtualDubMod - F/OSS for win32 (typically AVI files)
  • tmpgenc - freeware for win32 for MPG

CLI

ImageMagick

ImageMagick is F/OSS for any OS and can create MPG or GIF from multiple stills. It is installed on all NUCAPT computers. To convert a series of gifs into an animated gif, you can issue the command:

convert -loop 0 -delay 10 *.gif movie.gif

gifsicle

gifsicle is able to edit animated gifs. To separate an animated gif into individual frames ("explode"):

gifsicle -e movie.gif

To optimize a gif:

gifsicle -b -O2 movie.gif

To lower the number of colors in a gif:

gifsicle -b -k 16 movie.gif

Every nth frame

A common need is to take every nth frame to reduce the number of frames in a movie, and thus the size of the movie. A bash script similar to the following will take every third frame from a series of 1000 gifs from gifsicle:

for i in `seq -f%04.f 0 3 1000`
do
  cp movie.gif.$i temp
done

Other programs

  • mencoder - F/OSS for any OS
  • transcode - F/OSS for any OS