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‐ Motion JPEG is 4:2:2, and most implementations allow you to specify a data rate or quality level.
‐ Typically, data rates of 50 Mbps or greater are considered broadcast quality.
3. Uncompressed codecs
‐ More and more cards support true 4:2:2 uncompressed video. The data rates are large, and the
quality is no better than a lossless compression.
‐ One significant advantage of some uncompressed codecs is support for 10‐bit‐per‐channel captures,
which can perform better for analog and especially SDI sources. ‐ High‐end video editing
applications, such as After Effects Professional, are able to process video in more than 8 bits per
channel, improving the quality.
‐ Because uncompressed codecs have such high data rates, you should use a fast drive system, such as
a RAID (redundant array of independent disks) system.
Exporting video
‐ If features in other encoding tools are required, for example, volume encoding to multiple output
formats, it is useful to export an intermediate file from the timeline and use the exported file for
further processing.
Exporting to file
A file you export for later processing is called an intermediate file. (Reason for this = to provide high
quality in the most useful format without introducing any compression artifacts).
Choosing whether to preprocess or to avoid rendering
When to apply preprocessing? During the rendering phase or later?
‐ Preprocessing during rendering generally results in a smaller file, but adds more rendering time.
‐ Basically, to avoid rendering, you use the same codec and file format as your source video.
‐If you don't preprocess, you don't need to uncompress and then recompress unmodified frames—
instead, you copy them from the source into the output. ‐ In Adobe Premiere Pro, you'd turn off
the Recompress option in the Video
pane of the Export Movie Settings dialog box. For this process to work, the video must truly be
unchanged with the same frame rate, frame size, pixel aspect ratio, and so on. The simplest way to
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