Apple Final Cut Express HD: New Features - Manual (Page 2)

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Since HDV is high definition video using MPEG-2 compression, it requires a slightly
different workflow than intraframe formats such as DV. With DV, each frame contains
all the information needed to display the video. With HDV video, only some of the
frames contain all the information required for display. These are called
I-frames .
Grouped together with several subsequent frames (called B-frames and P-frames ),
these frames form a GOP (Group of Pictures). This MPEG-2 footage needs to be
processed, or encoded, into an intraframe format before you can begin editing in
Final Cut Express HD. This format is called the Apple Intermediate Codec. Encoding
is done automatically for you during the capture process.
Comparing the Data Rates of HDV and DV
It is useful to know the data rates for the Apple Intermediate Codec, so you can plan for
the storage requirements for HDV footage. For example, 1 hour of 720p30 HDV video
requires 23 gigabytes (GB) of disk space.
Note: Data rates for the Apple Intermediate Codec are variable; these figures are
approximate and may vary according to the complexity of your footage. Images with a
lot of detail have a higher data rate, while images with less detail have a lower data
rate.
HDV Devices
Before you can work with HDV, you need an HDV camcorder. Final Cut Express HD
supports a number of camcorders for HDV capture and output. To make sure that you
have a qualified HDV device, be sure to check the “Final Cut Express HD Qualified
Devices” document, located at
http://www.apple.com/finalcutexpress/specs.html .
Format Frame size Data rate
DV NTSC 720 x 480 3.6 MB/sec. (equivalent to
12 GB/hr.)
DV PAL 720 x 576 3.6 MB/sec. (equivalent to
12 GB/hr.)
Apple Intermediate Codec
720p30 HDV
1280 x 720 7 MB/sec. (equivalent to
23 GB/hr.)
Apple Intermediate Codec
1080i50 HDV
1440 x 1080 14 MB/sec. (equivalent to
46 GB/hr.)
Apple Intermediate Codec
1080i60 HDV
1440 x 1080 11 MB/sec. (equivalent to
38 GB/hr.)