PRG Mbox - MBOX NETWORKING GUIDELINES

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MBOX® USER MANUAL
CREATING CUSTOM CONTENT
Movies
As mentioned earlier in this manual, Mbox will try to play any QuickTime movie - no matter what codec it may be -
however, movies that are formatted incorrectly may not play at all or may not play as well as movies that are formatted
correctly. While Mbox will do the best job possible to play any compatible movie content, if the le is not optimized
specically for Mbox, poor results may occur. There are many elements of movie les that need to be considered when
creating content: le extension, codec, compression, frame rate, resolution, and audio. The following sections take an in
depth look at each of these requirements.
The Mbox application now uses AVFoundation technology instead of QuickTime 7 as the basis for its playback engine,
and therefore, there are some changes to what content is compatible. The QuickTime Player application on the Mbox
computer also uses AVFoundation technology. QuickTime Player will attempt to open any movie le, but will display a
prompt when the le has to be converted before playback. As a general rule of thumb, Mbox is capable of playing any
le that the QuickTime application on the Mbox computer can open and play without conversion.
File Extension
QuickTime movies can have all sorts of le extensions. But Mbox will only open movie les with the .mov or .mp4 le
extensions. Keep in mind that even though Mbox may try to open and play a le because it uses one of these three le
extensions, this does not guarantee that the movie will play! It is a good idea to always test all les in advance.
Note: Mbox can also open and play Quartz Composer (.qtz) les. However, these are not considered QuickTime movie
les and follow different rules for le extension and formatting.
Codec
Beyond the le extension, a movie’s codec (coder/decoder) is very important. Mbox will try to play any QuickTime movie
with the right le extension, no matter what its codec is. However only movies using the Apple ProRes, Photo-JPEG,
H.264, Hap, or DV codecs will actually play. And within that list of codecs, only the ProRes and Photo-JPEG codecs
are considered as “preferred codecs.” Movies using one of the two preferred codecs use the enhanced Mbox playback
engine and can take advantage of all of the Mbox functionality. Other movies using non-preferred codecs are handed off
to a playback engine (based on AVFoundation) that has slightly less functionality than the Mbox engine.
The ProRes codec should be the rst choice when creating content for Mbox. Photo-JPEG and Hap will work well,
although there are some additional considerations that must be taken into account when using these two codecs.
Movies created using any other codecs may not play as well as movies using a preferred codec:
+ Apple ProRes is a high-quality, spatially compressed, scalable codec that was designed to compress HD content
sufciently to keep bitrates at SD levels. Decompression of ProRes can be multi-threaded, providing better
performance on computers with multiple CPU cores. ProRes is currently the best choice of codec for use with
Mbox. The bitrate of ProRes content can be very high, so care should be used when creating movies in this format.
+ Photo-JPEG is another quality, scalable format that uses spatial compression. Photo-JPEG movies can be of any
resolution (within performance limits) and can take full advantage of Mbox’s many playmodes. Photo-JPEG is a
processor-intensive codec, so care must be taken to keep movies to a reasonable quality setting otherwise playback
may not be smooth. Typically, a setting of Medium or 60%-80% is appropriate for Mbox. Setting the quality level
above 80% will have no impact on the quality of the image as displayed by Mbox.