Imagine Selenio X50, Installation And Operation Manual, Page: 60 / 136

Chapter 3
Controls
46
The SDI Routing Mode makes it possible for you to make the SDI 2 output the same as, or
separate from the SDI 1 output. If you select Dual , SDI 1 and SDI 2 can have separate
outputs. If you select Linked , SDI 2 will carry the same output signal as SDI 1. (This setting
also affects the available output formats for Analog and HDMI).
Note: When you adjust horizontal or vertical timing on one output SDI channel, the other
SDI channel may produce video “glitches”. Ensure that your X50 is not on-air if you make
adjustments to the horizontal or vertical output timing.
The Audio/Video Sync parameter provides automatic tracking of the audio and video
signals (see Figure 3-21 on page 52). However, this timing is based on the output of the
primary (SDI 1) channel. Because different formats may have different propagation delays,
the SDI 2 audio and video tracking may not be aligned with SDI 1. Audio/video alignment
always follows SDI 1; the A/V alignment on the SDI 2 channel cannot be controlled
separately.
Frame Rate
Conversion
The X50 provides basic automatic frame rate conversion. When the X50 enables the FRC,
audio/video alignment is variable ±1 frame. There must be a valid reference available for the
selected output standard, and you must enable the
Sync mode in Audio/Video Sync .
When the conversion involves increasing the frame rate, frames are repeated as required;
when converting to a lower frame rate, frames are dropped. All of the frames at the output
are identical to the input frames with two exceptions: sometimes a frame is repeated a
second time, and sometimes a frame is dropped. If there is a lot of motion in the video, a
jerky motion (called judder) may appear when converting from one frame rate to another.
This is a normal artifact of basic frame rate conversion. Closed captioning and Teletext are
not supported when the FRC is in use.