posted this on November 15, 2010 10:46 am
This guide will outline some best practices for using video in your SlideRocket presentation. Performance of any media in SlideRocket depend on many factors, such as: type/size of monitor, overall size of the presentation, viewer connection speed, number and size of media files on the slides and within the presentations.
Dimensions: 800x600 or 1024x768 is best when viewing on standard monitor. If presentation will be broadcast on large screen, higher resolution video can be used
Bitrate: Depends on dimensions and video codec. For H.264, it is generally 1000-3000 kbps. The lower the bit rate, the more compressed the video. This means that quality will be lower, but that file size will be smaller
Frame Rate: Dependent on source used to create video and should remain unchanged from source file. Do not use variable frame rate
Encoding: MP4 video files are supported in their native format. Other video formats will be converted to MP4 format during import. Video formats that can be converted on import are: AVI, MOV, WMV, MPG, MPEG, FLV, ASF, 3GP, M4V, and VOB. The dimensions and frame rate of converted videos will be the same as the original version.
All of the factors above combine to create an overall file size, so there is no standard file size that is recommended.
SlideRocket does not accept individual files that are larger than 200MB and any single video more than 70MB will cause slower downloading time for viewer
For optimal results, select only 1 video per slide. This includes video that are hyperlinked to using the Play Asset feature
SlideRocket downloads locally each time it plays, rather than streaming, so there is no particular connection speed that is best.
Larger videos and larger presentations will take longer to download on viewers’ computers
For enhanced online playback, play presentation and video all the way through then leave browser open prior to presenting
MPEG-4 files contain metadata, including dimensions and length of video, in a "moov" atom.
SlideRocket requires setting "moov" atom at beginning of file for best results. This allows for your video to play while it is downloading
Some video tools put "moov" atom at end of file. In these cases, the video player does not have information it needs to start playing video until entire video has been downloaded. Due to performance impact this can have within SlideRocket, it is recommended to move “moov” atom to front of file using the setting called "progressive download," "streaming mode," or "fast start"
ADVANCED NOTE: For more technical information about this feature click here