Authors : Rejean Lau, Maziyar Khorasani, Yongie Liu, Ramkrishna Swamy
Date : Dec 5, 2004
Topic : 8 bit YCbCr to RGB colour space converter for Virtex II Multimedia


An app note was published by Xilinx for a colour space YCbCr to RGB converter
and several implemenations are published, available both VHDL and Verilog.

http://www.xilinx.com/bvdocs/appnotes/xapp283.pdf


However, the implementation provided is for the higher resolution 10 bit input.

We have modified and tested the behavioral implementation for 8 bit input,
which now implements the equations

R'=1.164(Y'-16) + 1.596(Cr-128)
G'=1.164(Y'-16) - (0.813)(Cr-128)-0.392(Cb-128)
B'=1.164(Y'-16)+2.017(Cb-128)

Whereas the original 10 bit input implemented the equations

R'=1.164(Y'-64)+1.596(Cr-512)
G'=1.164(Y'-64)-(0.813)(Cr-512)-0.392(Cb-512)
B'=1.164(Y'-64)+2.017(Cb-512)


This 8 bit pipelined version has been synthesized with an excellent max clock
speed of 153.563 MHz (latency of 3) and consumes no memory resources.

A testbench and synthesis report is also provided.