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MBOX® USER MANUAL
MEDIA CONTENT
File Type Specications
Previous versions of Mbox used Apple’s QuickTime® technology for image and movie rendering and playback. The
Mbox v4 software uses Apple’s AVFoundation® technology instead. AVFoundation offers modern API’s with better
performance than QuickTime. However AVFoundation has fewer native le formats and movie codecs. The following le
types are supported:
Still Image Files
PNG (.png), JPEG (.jpeg or .jpg), TIFF (.tiff or .tif) for still image les.
+ For still images with or without transparency, PNG is the best choice.
+ For still images not requiring transparency, JPEG is a good choice.
+ For still images with transparency, TIFF les can be used but may take longer to load due to their large le size.
Movie Files
Mbox continues to use the QuickTime container format (.mov) for most movie les and can now also use the MPEG4
container format (.mp4) for H.264 movie les. Spatially-compressed codecs (Photo-JPEG or ProRes) will usually provide
better playback results than temporally-compressed codecs like H.264.
+ Apple ProRes - The ProRes family of codecs includes ve versions. ProRes Proxy has the lowest bitrate, but
consequently the lowest quality. Light and Normal are the recommended codecs for movies. High Quality can be
used if the resulting bitrate is not too high (200Mb/sec or lower). ProRes 4444+ may be used if transparency is
required in the movie le, but as with ProRes HQ, keep the bitrate below 200Mb/sec if possible. All modern Mac
computers can play ProRes movies. But unless the full ProRes codec is installed, the computer is unable to encode
ProRes les (e.g. when using Mbox File Convertor).
+ Photo JPEG – Medium-High (60-80%). The quality of Photo-JPEG is not equal to that of the ProRes, but it typically
has a lower bitrate and therefore can place a lighter load on the system if a lot of movies are being played.
+ Hap - The Hap family of codecs includes four versions: Hap, Hap Q, Hap Alpha, and Hap Q Alpha. The Hap codec,
and especially Hap Q and Hap Q Alpha, trade off higher bitrates for lower CPU load, so keeping the bitrate at a
reasonable level is important. The Hap codec does not need to be installed to play Hap movies in Mbox, but must
be installed to encode Hap movies or to play them in other QuickTime-based applications.
+ H.264 - H.264 works with Mbox v4, and bitrates can be low for quite high-quality. However, because H.264 is
temporally compressed it can’t be used with all of the available playmodes in Mbox and playspeed adjustments
may lead to jerky playback. This, combined with stability concerns over H.264 decoding means that H.264 is not
recommended.
Image Sequences
Mbox v4.1 adds the ability to play image sequences. Image sequences are used like movies, but rather than being a
single movie le, they are made up of multiple still image les. Mbox supports JPEG, PNG, and TIFF image sequences:
+ JPEG images will produce the smallest le size, but the quality may not be as good as with PNG or TIFF les.
+ PNG images provide the best compromise between le size and quality. Also, PNG supports an alpha channel in the
image.
+ TIFF images have the highest quality (they can be virtually lossless) and support an alpha channel. But TIFF les
tend to take up a lot of disk space.