/////////////////////////////////////////////////////////////////////
//// ////
//// RGB to YCrCb Color Space converter ////
//// ////
//// Converts RGB values to YCrCB (YUV) values ////
//// Y = 0.299R + 0.587G + 0.114B ////
//// Cr = 0.713(R - Y) ////
//// Cb = 0.565(B - Y) ////
//// ////
//// Author: Richard Herveille ////
//// richard@asics.ws ////
//// www.asics.ws ////
//// ////
//// ////
/////////////////////////////////////////////////////////////////////
//// ////
//// Copyright (C) 2001 Richard Herveille ////
//// richard@asics.ws ////
//// ////
//// This source file may be used and distributed without ////
//// restriction provided that this copyright statement is not ////
//// removed from the file and that any derivative work contains ////
//// the original copyright notice and the associated disclaimer.////
//// ////
//// THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY ////
//// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED ////
//// TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS ////
//// FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL THE AUTHOR ////
//// OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, ////
//// INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES ////
//// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE ////
//// GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR ////
//// BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF ////
//// LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT ////
//// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT ////
//// OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE ////
//// POSSIBILITY OF SUCH DAMAGE. ////
//// ////
/////////////////////////////////////////////////////////////////////
// CVS Log
//
// $Id: rgb2ycrcb.v,v 1.1 2002/03/26 07:25:01 rherveille Exp $
//
// $Date: 2002/03/26 07:25:01 $
// $Revision: 1.1 $
// $Author: rherveille $
// $Locker: $
// $State: Exp $
//
// Change History:
// $Log: rgb2ycrcb.v,v $
// Revision 1.1 2002/03/26 07:25:01 rherveille
// Initial revision
//
`timescale 1ns/10ps
module rgb2ycrcb(clk, ena, r, g, b, y, cr, cb);
//
// inputs & outputs
//
input clk;
input ena;
input [9:0] r, g, b;
output [9:0] y, cr, cb;
reg [9:0] y, cr, cb;
//
// variables
//
reg [21:0] y1, cr1, cb1;
//
// module body
//
// step 1: Calculate Y, Cr, Cb
//
// Use N.M format for multiplication:
// Y = 0.299 * R.000 + 0.587 * G.000 + 0.114 * B.000
// Y = 0x132 * R + 0x259 * G + 0x074 * B
//
// Cr = 0.713(R - Y)
// Cr = 0.500 * R.000 + -0.419 * G.000 - 0.0813 * B.000
// Cr = (R >> 1) - 0x1AD * G - 0x053 * B
//
// Cb = 0.565(B - Y)
// Cb = -0.169 * R.000 + -0.332 * G.000 + 0.500 * B.000
// Cb = (B >> 1) - 0x0AD * R - 0x153 * G
// calculate Y
reg [19:0] yr, yg, yb;
always@(posedge clk)
if (ena)
begin
yr
FPGA/CPLD