CMP_chromaMatte.c

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/*
 * $Id: CMP_chromaMatte.c 36276 2011-04-21 15:53:30Z campbellbarton $
 *
 * ***** BEGIN GPL LICENSE BLOCK *****
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version. 
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * The Original Code is Copyright (C) 2006 Blender Foundation.
 * All rights reserved.
 *
 * The Original Code is: all of this file.
 *
 * Contributor(s): none yet.
 *
 * ***** END GPL LICENSE BLOCK *****
 */

#include "../CMP_util.h"

/* ******************* Chroma Key ********************************************************** */
static bNodeSocketType cmp_node_chroma_in[]={
        {SOCK_RGBA,1,"Image", 0.8f, 0.8f, 0.8f, 1.0f, 0.0f, 1.0f},
        {SOCK_RGBA,1,"Key Color", 0.8f, 0.8f, 0.8f, 1.0f, 0.0f, 1.0f},
        {-1,0,""}
};

static bNodeSocketType cmp_node_chroma_out[]={
        {SOCK_RGBA,0,"Image", 0.8f, 0.8f, 0.8f, 1.0f, 0.0f, 1.0f},
        {SOCK_VALUE,0,"Matte",0.0f, 0.0f, 0.0f, 1.0f, 0.0f, 1.0f},
        {-1,0,""}
};

static void do_rgba_to_ycca_normalized(bNode *UNUSED(node), float *out, float *in)
{
        rgb_to_ycc(in[0],in[1],in[2], &out[0], &out[1], &out[2], BLI_YCC_ITU_BT601);

        //normalize to 0..1.0
        out[0]=out[0]/255.0;
        out[1]=out[1]/255.0;
        out[2]=out[2]/255.0;

        //rescale to -1.0..1.0
        out[0]=(out[0]*2.0)-1.0;
        out[1]=(out[1]*2.0)-1.0;
        out[2]=(out[2]*2.0)-1.0;

//      out[0]=((out[0])-16)/255.0;
//      out[1]=((out[1])-128)/255.0;
//      out[2]=((out[2])-128)/255.0;
        out[3]=in[3];
}

static void do_ycca_to_rgba_normalized(bNode *UNUSED(node), float *out, float *in)
{
        /*un-normalize the normalize from above */
        in[0]=(in[0]+1.0)/2.0;
        in[1]=(in[1]+1.0)/2.0;
        in[2]=(in[2]+1.0)/2.0;

        in[0]=(in[0]*255.0);
        in[1]=(in[1]*255.0);
        in[2]=(in[2]*255.0);

        //      in[0]=(in[0]*255.0)+16;
//      in[1]=(in[1]*255.0)+128;
//      in[2]=(in[2]*255.0)+128;
        ycc_to_rgb(in[0],in[1],in[2], &out[0], &out[1], &out[2], BLI_YCC_ITU_BT601);
        out[3]=in[3];
}

static void do_chroma_key(bNode *node, float *out, float *in)
{
        NodeChroma *c;
        float x, z, alpha;
        float theta, beta, angle, angle2;
        float kfg;

        c=node->storage;

        /* Algorithm from book "Video Demistified," does not include the spill reduction part */

        /* find theta, the angle that the color space should be rotated based on key*/
        theta=atan2(c->key[2], c->key[1]);

        /*rotate the cb and cr into x/z space */
        x=in[1]*cos(theta)+in[2]*sin(theta);
        z=in[2]*cos(theta)-in[1]*sin(theta);

        /*if within the acceptance angle */
        angle=c->t1*M_PI/180.0; /* convert to radians */

        /* if kfg is <0 then the pixel is outside of the key color */
        kfg=x-(fabs(z)/tan(angle/2.0));

        out[0]=in[0];
        out[1]=in[1];
        out[2]=in[2];

        if(kfg>0.0) {  /* found a pixel that is within key color */
                alpha=(1.0-kfg)*(c->fstrength);

                beta=atan2(z,x);
                angle2=c->t2*M_PI/180.0;

                /* if beta is within the cutoff angle */
                if(fabs(beta)<(angle2/2.0)) {
                        alpha=0.0;
                }

                /* don't make something that was more transparent less transparent */
                if (alpha<in[3]) {
                        out[3]=alpha;
                }
                else {
                        out[3]=in[3];
                }
        }
        else { /*pixel is outside key color */
                out[0]=in[0];
                out[1]=in[1];
                out[2]=in[2];
                out[3]=in[3]; /* make pixel just as transparent as it was before */
        }
}

static void node_composit_exec_chroma_matte(void *data, bNode *node, bNodeStack **in, bNodeStack **out)
{
        CompBuf *cbuf;
        CompBuf *chromabuf;
        NodeChroma *c;
        
        if(in[0]->hasinput==0) return;
        if(in[0]->data==NULL) return;
        if(out[0]->hasoutput==0 && out[1]->hasoutput==0) return;
        
        cbuf= typecheck_compbuf(in[0]->data, CB_RGBA);
        
        chromabuf= dupalloc_compbuf(cbuf);
        
        c=node->storage;
        
        /*convert rgbbuf to normalized chroma space*/
        composit1_pixel_processor(node, chromabuf, cbuf, in[0]->vec, do_rgba_to_ycca_normalized, CB_RGBA);
        /*convert key to normalized chroma color space */
        do_rgba_to_ycca_normalized(node, c->key, in[1]->vec);
        
        /*per pixel chroma key*/
        composit1_pixel_processor(node, chromabuf, chromabuf, in[0]->vec, do_chroma_key, CB_RGBA);
        
        /*convert back*/
        composit1_pixel_processor(node, chromabuf, chromabuf, in[0]->vec, do_ycca_to_rgba_normalized, CB_RGBA);
        
        out[0]->data= chromabuf;
        if(out[1]->hasoutput)
                out[1]->data= valbuf_from_rgbabuf(chromabuf, CHAN_A);
        
        generate_preview(data, node, chromabuf);

        if(cbuf!=in[0]->data)
                free_compbuf(cbuf);
}


static void node_composit_init_chroma_matte(bNode *node)
{
        NodeChroma *c= MEM_callocN(sizeof(NodeChroma), "node chroma");
        node->storage= c;
        c->t1= 30.0f;
        c->t2= 10.0f;
        c->t3= 0.0f;
        c->fsize= 0.0f;
        c->fstrength= 1.0f;
}

void register_node_type_cmp_chroma_matte(ListBase *lb)
{
        static bNodeType ntype;

        node_type_base(&ntype, CMP_NODE_CHROMA_MATTE, "Chroma Key", NODE_CLASS_MATTE, NODE_PREVIEW|NODE_OPTIONS,
                cmp_node_chroma_in, cmp_node_chroma_out);
        node_type_size(&ntype, 200, 80, 300);
        node_type_init(&ntype, node_composit_init_chroma_matte);
        node_type_storage(&ntype, "NodeChroma", node_free_standard_storage, node_copy_standard_storage);
        node_type_exec(&ntype, node_composit_exec_chroma_matte);

        nodeRegisterType(lb, &ntype);
}