Apple Motion 5.1.1 - Manual (Page 1055)

Chapter 26 Video and file formats 1055
Note: Uncompressed 8-bit and 10-bit 4:2:2 movies do not support alpha channels.
DVCPRO HD
A high-definition video format used to capture video digitally from FireWire-enabled DVCPRO HD
compatible decks. (Not to be confused with DVCPRO 25 or DVCPRO 50, which are both standard-
definition formats.) This format supports a number of frame sizes and frame rates, including a
24p format that offers variable speed via a variable frame rate technology. DVCPRO HD uses 4:2:2
color sampling for high color fidelity, and has a fixed data rate of 12.5 MB/sec.
Note: DVCPRO HD movies do not support alpha channels.
DVCPRO 50
A standard-definition codec used to capture video digitally from FireWire-enabled,
DVCPRO 50-compatible camcorders and decks. Although it’s similar to the DV codec because
DVCPRO 50 is imported as YUV encoded video, it produces considerably higher quality video
because it uses less compression. (DVCPRO 50 uses a 3:3:1 compression ratio, versus DV’s 5:1
compression ratio.) DVCPRO 50 also uses 4:2:2 color sampling for high color fidelity, as opposed
to DV’s 4:1:1 color sample rate. DVCPRO 50 has a fixed data rate of 7 MB/sec.
Note: DVCPRO 50 movies do not support alpha channels.
Third-party codecs
Numerous video-editing solutions use different codecs, some of which may be available for
installation to encourage interoperability. For more information, contact the manufacturer of the
editing system.
Note: Most third-party codecs cannot have alpha channels.
Field order
When a video display is fed an interlaced video signal, each frame of video is split into two fields,
each of which contains a set of alternating lines of horizontal resolution running across the
screen. Standard-definition NTSC and PAL are both interlaced video formats, while some high-
definition video formats, and all video displayed on a computer screen, are progressive-scanned
video formats. With progressive scanning, these lines are drawn one at a time, from the top of
the screen to the bottom.
When you record interlaced footage with a camcorder, each video frame is split into two fields,
each containing half of the total lines of resolution in the frame. The first field is recorded, then
the second, one after the other, so both fields constitute one frame. When you play the video
back, the monitor displays each recorded frame in succession, first drawing one field, then
the other.
Field order refers to the order in which each pair of video fields is recorded. Because video fields
are recorded sequentially, it’s as if each 29.97 fps clip is really playing at 60 “frames” per second.
There are two options for field order:
•
Upper (Field 2 is dominant, so the second field is drawn first.)
•
Lower (Field 1 is dominant, so the first field is drawn first.)
Generally, Upper is used by 640 x 480 systems, while Lower is most common in professional
720 x 486 and DV 720 x 480 systems.
67% resize factor