Sound Devices PIX 220, Руководство пользователя и техническая информация

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PIX 220i, 240i, 220, 240 User Guide and Technical Information
v. 3.01 Features and specifications are subject to change. Visit www.sounddevices.com for the latest documentation.
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1080p30/29.97). When any of these options are selected, the PIX recorder will record in the indicated
integer frame rate if the input video is an integer frame or record in the indicated non-integer frame
rate if the input video is a non-integer frame rate.
Not all frame rate conversions are visually desirable. When the OSD Item File Resolution/Rate is
red, the conversion of the frame rate of the input video to the frame set by Video

File Resolution/
Rate
will contain a inite amount of motion judder. For example, if the incoming video is 720p60 and
Video

File Resolution/Rate is set to 720p50, the cadence of dropped frames may be noticeable
depending on the content. Conversions which are simply 1:2 or 2:1 (such as 1080i59.94 to 1080p29.97)
introduce no motion judder. For these conversions, the OSD Item
File Resolution/Rate stays white.
When the input video signal is 720p24 or 720p23.976, up-, down-, and cross-conversion is not available.
3:2 Pulldown Removal
Many cameras which shoot with a shuter speed of 24/23.976 frames per second will output signal on
the HDMI or SDI output at 60i/59.94i. To achieve this, the camera performs a “3:2 pulldown” pro
-
cess. The 3:2 pulldown process splits each frame into 2 ields and duplicates a ield periodically. The
PIX recorders are capable of removing 3:2 pulldown from a 60i/59.94i signal and converting it back
to 24/23.976 progressive frames per second in real-time. The PIX 3:2 removal process actively views
video ields looking for duplicates. When these duplicates are sensed, then this cadence is locked in
and the appropriate extra ields are removed. The process depends on motion in the incoming video.
The OSD File Resolution/Rate changes from orange to white when this cadence is detected:
Orange
: No 3:2 pulldown sensed in 60i/59.94i input signal. In
-
put video is being converted to 24p/23.976p using a conversion
process which drops frames and may introduce judder.
White
: 3:2 pulldown sensed in 60i/59.94i input video signal.
Input video signal is being converted to 24p/23.976p using 3:2
pulldown removal which recreates 24p/23.976p as it is cap
-
tured from the camera’s shuter.