While Kaltura supports a wide range of video formats and codecs, there are some recommended specifications for creating source files. These will ensure that your source file is quickly transcoded to multiple flavors (renditions), while offering the optimal video and audio quality.
The lists and tables below are designed to supply you with the recommended settings you should use when compressing a video project in software as Final Cut Pro, Avid, Compressor, Adobe Premiere and others.
Please note: this is a best practices document. Other settings are likely to work as well.
Recommended Video Settings
x1.5-2 of the largest flavor
As big as the largest desired flavor
Multiples of 16 (see below)
Keep the original
Some editing and transcoding software include various export profiles. We recommended exporting using the QuickTime MPEG-4 profile. In the options choose the following:
Multi pass –multi-pass will provide better quality (although Kaltura can convert single-pass file as well).
VBR vs. CBR - VBR (variable bitrate) usually provides better quality than CBR (constant bitrate).
Frame Sizes with Recommended Bitrates
An ideal source bitrate is 6,000-8,000 Kbps, however for smaller dimensions you may use lower bitrates as shown in the table below (default kaltura flavors dimensions appear in bold).
|1920x1080 (1080p)||6,000-8,000 Kbps|
|1280x720 (720p)||3,750-5,000 Kbps|
|1024x720 (iPad)||3,750-5,000 Kbps|
Recommended Audio Settings
44.1 kHz or lower
Peaks, low sound