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AirSpeed Multi Stream Overview
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AutoAFD
If one of the AutoAFD options is selected as the Up, Down, or SD-Cross convert option,
then AirSpeed Multi Stream will use an intelligent algorithm to reshape or convert the video
image. The conversion from input format to output format is detailed in Appendix D,
Down, Cross Convert (UDX) Examples” on page 381
If the video being played does not contain AFD information, then AirSpeed Multi Stream
uses the “default” specified in the configuration settings. For example, if AFD exists in the
incoming video, the setting “AutoAFD Default Pillarbox” follows the approach outlined in
Appendix D, and will use Pillarbox, if AFD does not exist in the video.
ATC and VITC Timecode
For HD streams, we use Ancillary TimeCode (ATC). ATC is always stored and displayed in
25/30 Hz timing, even for progressive video formats. AirSpeed Multi Stream implements
SMPTE RP188 Ancillary TimeCode.
For SD streams, the timecode is Vertical Interval TimeCode (VITC).
Generally, when a clip is recorded, you can select from a variety of timecode choices. The
selected option is used to set the clip’s base timecode.
At playback time, you can select whether to use the clip’s base timecode, or the frame
embedded timecode, for output to ATC or VITC.
Video Format
In SDI video, the ancillary data that defines the video format is called AFD, or Active
Format Description. AFD is defined as a 4-bit number; there are 16 possible values.
However, many of these are reserved and are not used. The most common AFD values
include:
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SD, AFD=9: 4:3 image
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SD, AFD=10: 16:9 image, letterboxed (black bars at top and bottom)
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HD, AFD=10: 16:9 image
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HD, AFD=9: 4:3 image, pillarboxed (black bars on left and right sides)
Summary of Contents for AirSpeed Multi Stream
Page 1: ...Avid AirSpeed Multi Stream Installation and User s Guide...
Page 6: ...6...
Page 22: ...22...
Page 178: ...5 Configuring the Software with a Standalone Transfer Manager 178...
Page 326: ...10 Working with the Remote Console 326...
Page 344: ...11 Maintaining Your AirSpeed Multi Stream 344...
Page 362: ...A Specifications 362...
Page 380: ...C Network Teaming 380...
Page 390: ...390 Taiwan EMC Regulations Taiwan EMC Regulations BSMI Class A EMC Warning...
Page 397: ...Index 397...