/////////////////////////////////////////////////////////////////////////                                                             ////////  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/10psmodule 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 <= #1 10'h132 * r;			yg <= #1 10'h259 * g;					yb <= #1 10'h074 * b;			y1 <= #1 yr + yg + yb;		end	// calculate Cr	reg [19:0] crr, crg, crb;	always@(posedge clk)		if (ena)		begin			crr <= #1 r << 9;			crg <= #1 10'h1ad * g;					crb <= #1 10'h053 * b;			cr1 <= #1 crr - crg - crb;		end	// calculate Cb	reg [19:0] cbr, cbg, cbb;	always@(posedge clk)		if (ena)		begin			cbr <= #1 10'h0ad * r;			cbg <= #1 10'h153 * g;					cbb <= #1 b << 9;			cb1 <= #1 cbb - cbr - cbg;		end	//	// step2: check boundaries	//	always@(posedge clk)		if (ena)		begin			// check Y			y <= #1 (y1[19:10] & {10{!y1[21]}}) | {10{(!y1[21] && y1[20])}};			// check Cr			cr <= #1 (cr1[19:10] & {10{!cr1[21]}}) | {10{(!cr1[21] && cr1[20])}};			// check Cb			cb <= #1 (cb1[19:10] & {10{!cb1[21]}}) | {10{(!cb1[21] && cb1[20])}};		endendmodule