IPSR-VIDEO Altera, IPSR-VIDEO Datasheet - Page 76

• Manufacturer Part Number: IPSR-VIDEO
• Description: RENEWAL Of IPS-VIDEO
• Manufacturer: Altera
• Series: IP Suitesr

Specifications of IPSR-VIDEO

• Software Application: IP CORE, SUITES
• Supported Families: Arria GX, Cyclone II, HardCopy II, Stratix II
• Features: Common Avalon Streaming (Avalon-St) Interface And Avalon-St Video Protocol
• Core Architecture: FPGA
• Core Sub-architecture: Arria, Cyclone, Stratix
• Rohs Compliant: NA
• Lead Free Status / RoHS Status: na

4–18
Video and Image Processing Suite User Guide
1
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The following pseudo-code illustrates the design of functions that double-buffer their
control (that is, all MegaCore functions except the Gamma Corrector, the Alpha
Blending Mixer and some Scaler parameterizations):
The Gamma Corrector does not double buffer its control data but the algorithm
described in the previous paragraph is still largely applicable.
Most Video and Image Processing Suite MegaCore functions with a slave interface
read and propagate non-image data packets from the input stream until the image
data header (0) of an image data packet has been received. The status bit is then set to
0 and the MegaCore function waits until the Go bit is set to 1 if it is not already. Once
the Go bit is set to 1, the MegaCore function buffers control data, sets its status bit back
to 1 and starts processing image data.
There is a small amount of buffering at the input of each Video and Image Processing
Suite MegaCore function and you should expect that a few samples are read and
stored past the image data header even if the function is stalled.
You can use the Go and Status registers in combination to synchronize changes in
control data to the start and end of frames. For example, suppose you want to build a
system with a Gamma Corrector MegaCore function where the gamma look-up table
is updated between each video frame.
You can build logic (or program a Nios
as follows:
1. Set the Go bit to zero. This causes the MegaCore function to stop processing at the
2. Poll the Status bit until the MegaCore function sets it to zero. This occurs at the
3. Update the gamma look-up table.
4. Set the Go bit to one. This causes the MegaCore function to start processing the
5. Poll the Status bit until the MegaCore function sets it to one. This occurs when the
Register 1 is the Status register. Bit zero of this register is the Status bit, the
function does not use all other bits. The function sets the Status bit to 1 when it is
running, and zero otherwise. External logic attached to the control port should not
attempt to write to the Status register.
go = 0;
while (true)
{
}
end of the current frame.
end of the current frame, after the MegaCore function has stopped processing
data.
next frame.
MegaCore function has started processing the next frame (and therefore setting
the Go bit to zero causes it to stop processing at the end of the next frame).
read_non_image_data_packets();
status = 0;
while (go != 1)
read_control(); // Copies control to internal registers
status = 1;
send_image_data_header();
process_frame();
wait;
®
II processor) to control the gamma corrector
January 2011 Altera Corporation
Avalon-MM Slave Interfaces
Chapter 4: Interfaces