2. Advantages of DVCPRO HD
2-2 DVCPRO's Intraframe Compression
System: Designed to Retain All Image
Information
All DVCPRO equipment uses intraframe compression. Data is produced and
compressed independently for each frame, even in the case of DVCPRO HD and
the huge amount of data it captures. This helps maintain superior pictures, sound
and reliability not only in nonlinear editing, but also in tape editing using VTRs. You
get greater editing flexibility and higher-quality results.
Compared to DVCPRO, an MPEG2-based system uses interframe compression.
A number of frames are formed into a group (called a GOP, for group of pictures)
for processing. In each GOP, only frame I (for Initial) contains the entire set of image
data. The subsequent frames P (Prediction) or B (Bi-directional) include the data
that is different from the data in frame I.
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