User guide

Table Of Contents
Chapter 23: Switch MegaCore Function 23–3
Parameter Settings
January 2013 Altera Corporation Video and Image Processing Suite
User Guide
Latency
Table 231 lists the approximate latency from the video data input to the video data
output for typical usage modes of the Switch MegaCore function. You can use this
table to predict the approximate latency between the input and the output of your
video processing pipeline.
The latency is described using one or more of the following measures:
the number of progressive frames
the number of interlaced fields
the number of lines when less than a field of latency
a small number of cycles O (cycles)
The latency is measured with the assumption that the MegaCore function is not being
stalled by other functions on the data path (the output ready signal is high).
1 The latency associated with the initial buffering phase, when a MegaCore function
first receives video data, is not included.
Parameter Settings
Table 232 lists the Switch MegaCore function parameters.
Table 23–1. Switch Latency
Mode Latency
All modes 2 cycles
Table 23–2. Switch Parameter Settings
Parameter Value Description
Bits per pixel per color plane 4–20, Default = 8 Choose the number of bits per pixel (per color plane).
Number of color planes 1–3, Default = 3 Choose the number of color planes.
Color planes are in parallel On or Off
Turn on to set colors planes in parallel, turn off to set colors planes in
sequence.
Number of input ports 1–12, Default = 2 Number of input ports (
din
and
alpha_in
).
Number of output ports 1–12, Default = 2 Number of output ports (
dout
and
alpha_out
).
Alpha enabled On or Off Turn on to enable the alpha ports.
Bits per pixel representing
the alpha coefficient
2, 4, or 8 Choose the number of bits used to represent the alpha coefficient.