Blender  V2.59
imageprocess.c
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00001 /*
00002  *
00003  * ***** BEGIN GPL LICENSE BLOCK *****
00004  *
00005  * This program is free software; you can redistribute it and/or
00006  * modify it under the terms of the GNU General Public License
00007  * as published by the Free Software Foundation; either version 2
00008  * of the License, or (at your option) any later version.
00009  *
00010  * This program is distributed in the hope that it will be useful,
00011  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00012  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00013  * GNU General Public License for more details.
00014  *
00015  * You should have received a copy of the GNU General Public License
00016  * along with this program; if not, write to the Free Software Foundation,
00017  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
00018  *
00019  * The Original Code is Copyright (C) 2001-2002 by NaN Holding BV.
00020  * All rights reserved.
00021  *
00022  * The Original Code is: all of this file.
00023  *
00024  * Contributor(s): none yet.
00025  *
00026  * ***** END GPL LICENSE BLOCK *****
00027  * This file was moved here from the src/ directory. It is meant to
00028  * deal with endianness. It resided in a general blending lib. The
00029  * other functions were only used during rendering. This single
00030  * function remained. It should probably move to imbuf/intern/util.c,
00031  * but we'll keep it here for the time being. (nzc)*/
00032 
00038 /*  imageprocess.c        MIXED MODEL
00039  * 
00040  *  april 95
00041  * 
00042  * $Id: imageprocess.c 36980 2011-05-28 13:11:24Z lmg $
00043  */
00044 
00045 #include <stdlib.h>
00046 
00047 #include "IMB_imbuf_types.h"
00048 #include "IMB_imbuf.h"
00049 #include "math.h"
00050 
00051 /* This define should be relocated to a global header some where  Kent Mein 
00052 I stole it from util.h in the plugins api */
00053 #define MAX2(x,y)                ( (x)>(y) ? (x) : (y) )
00054 
00055 /* Only this one is used liberally here, and in imbuf */
00056 void IMB_convert_rgba_to_abgr(struct ImBuf *ibuf)
00057 {
00058         int size;
00059         unsigned char rt, *cp = (unsigned char *)ibuf->rect;
00060         float rtf, *cpf = ibuf->rect_float;
00061 
00062         if (ibuf->rect) {
00063                 size = ibuf->x * ibuf->y;
00064 
00065                 while(size-- > 0) {
00066                         rt= cp[0];
00067                         cp[0]= cp[3];
00068                         cp[3]= rt;
00069                         rt= cp[1];
00070                         cp[1]= cp[2];
00071                         cp[2]= rt;
00072                         cp+= 4;
00073                 }
00074         }
00075 
00076         if (ibuf->rect_float) {
00077                 size = ibuf->x * ibuf->y;
00078 
00079                 while(size-- > 0) {
00080                         rtf= cpf[0];
00081                         cpf[0]= cpf[3];
00082                         cpf[3]= rtf;
00083                         rtf= cpf[1];
00084                         cpf[1]= cpf[2];
00085                         cpf[2]= rtf;
00086                         cpf+= 4;
00087                 }
00088         }
00089 }
00090 static void pixel_from_buffer(struct ImBuf *ibuf, unsigned char **outI, float **outF, int x, int y)
00091 
00092 {
00093         int offset = ibuf->x * y * 4 + 4*x;
00094         
00095         if (ibuf->rect)
00096                 *outI= (unsigned char *)ibuf->rect + offset;
00097         
00098         if (ibuf->rect_float)
00099                 *outF= (float *)ibuf->rect_float + offset;
00100 }
00101 
00102 /**************************************************************************
00103 *                            INTERPOLATIONS 
00104 *
00105 * Reference and docs:
00106 * http://wiki.blender.org/index.php/User:Damiles#Interpolations_Algorithms
00107 ***************************************************************************/
00108 
00109 /* BICUBIC Interpolation functions */
00110 /*  More info: http://wiki.blender.org/index.php/User:Damiles#Bicubic_pixel_interpolation
00111 */
00112 /* function assumes out to be zero'ed, only does RGBA */
00113 
00114 static float P(float k){
00115         float p1, p2, p3, p4;
00116         p1 = MAX2(k+2.0f,0);
00117         p2 = MAX2(k+1.0f,0);
00118         p3 = MAX2(k,0);
00119         p4 = MAX2(k-1.0f,0);
00120         return (float)(1.0f/6.0f)*( p1*p1*p1 - 4.0f * p2*p2*p2 + 6.0f * p3*p3*p3 - 4.0f * p4*p4*p4);
00121 }
00122 
00123 
00124 #if 0
00125 /* older, slower function, works the same as above */
00126 static float P(float k){
00127         return (float)(1.0f/6.0f)*( pow( MAX2(k+2.0f,0) , 3.0f ) - 4.0f * pow( MAX2(k+1.0f,0) , 3.0f ) + 6.0f * pow( MAX2(k,0) , 3.0f ) - 4.0f * pow( MAX2(k-1.0f,0) , 3.0f));
00128 }
00129 #endif
00130 
00131 void bicubic_interpolation_color(struct ImBuf *in, unsigned char *outI, float *outF, float u, float v)
00132 {
00133         int i,j,n,m,x1,y1;
00134         unsigned char *dataI;
00135         float a,b,w,wx,wy[4], outR,outG,outB,outA,*dataF;
00136 
00137         /* ImBuf in must have a valid rect or rect_float, assume this is already checked */
00138 
00139         i= (int)floor(u);
00140         j= (int)floor(v);
00141         a= u - i;
00142         b= v - j;
00143 
00144         outR = outG = outB = outA = 0.0f;
00145         
00146 /* Optimized and not so easy to read */
00147         
00148         /* avoid calling multiple times */
00149         wy[0] = P(b-(-1));
00150         wy[1] = P(b-  0);
00151         wy[2] = P(b-  1);
00152         wy[3] = P(b-  2);
00153         
00154         for(n= -1; n<= 2; n++){
00155                 x1= i+n;
00156                 if (x1>0 && x1 < in->x) {
00157                         wx = P(n-a);
00158                         for(m= -1; m<= 2; m++){
00159                                 y1= j+m;
00160                                 if (y1>0 && y1<in->y) {
00161                                         /* normally we could do this */
00162                                         /* w = P(n-a) * P(b-m); */
00163                                         /* except that would call P() 16 times per pixel therefor pow() 64 times, better precalc these */
00164                                         w = wx * wy[m+1];
00165                                         
00166                                         if (outF) {
00167                                                 dataF= in->rect_float + in->x * y1 * 4 + 4*x1;
00168                                                 outR+= dataF[0] * w;
00169                                                 outG+= dataF[1] * w;
00170                                                 outB+= dataF[2] * w;
00171                                                 outA+= dataF[3] * w;
00172                                         }
00173                                         if (outI) {
00174                                                 dataI= (unsigned char*)in->rect + in->x * y1 * 4 + 4*x1;
00175                                                 outR+= dataI[0] * w;
00176                                                 outG+= dataI[1] * w;
00177                                                 outB+= dataI[2] * w;
00178                                                 outA+= dataI[3] * w;
00179                                         }
00180                                 }
00181                         }
00182                 }
00183         }
00184 
00185 /* Done with optimized part */
00186         
00187 #if 0 
00188         /* older, slower function, works the same as above */
00189         for(n= -1; n<= 2; n++){
00190                 for(m= -1; m<= 2; m++){
00191                         x1= i+n;
00192                         y1= j+m;
00193                         if (x1>0 && x1 < in->x && y1>0 && y1<in->y) {
00194                                 if (do_float) {
00195                                         dataF= in->rect_float + in->x * y1 * 4 + 4*x1;
00196                                         outR+= dataF[0] * P(n-a) * P(b-m);
00197                                         outG+= dataF[1] * P(n-a) * P(b-m);
00198                                         outB+= dataF[2] * P(n-a) * P(b-m);
00199                                         outA+= dataF[3] * P(n-a) * P(b-m);
00200                                 }
00201                                 if (do_rect) {
00202                                         dataI= (unsigned char*)in->rect + in->x * y1 * 4 + 4*x1;
00203                                         outR+= dataI[0] * P(n-a) * P(b-m);
00204                                         outG+= dataI[1] * P(n-a) * P(b-m);
00205                                         outB+= dataI[2] * P(n-a) * P(b-m);
00206                                         outA+= dataI[3] * P(n-a) * P(b-m);
00207                                 }
00208                         }
00209                 }
00210         }
00211 #endif
00212         
00213         if (outI) {
00214                 outI[0]= (int)outR;
00215                 outI[1]= (int)outG;
00216                 outI[2]= (int)outB;
00217                 outI[3]= (int)outA;
00218         }
00219         if (outF) {
00220                 outF[0]= outR;
00221                 outF[1]= outG;
00222                 outF[2]= outB;
00223                 outF[3]= outA;
00224         }
00225 }
00226 
00227 
00228 void bicubic_interpolation(ImBuf *in, ImBuf *out, float u, float v, int xout, int yout)
00229 {
00230         
00231         unsigned char *outI = NULL;
00232         float *outF = NULL;
00233         
00234         if (in == NULL || (in->rect == NULL && in->rect_float == NULL)) return;
00235         
00236         pixel_from_buffer(out, &outI, &outF, xout, yout); /* gcc warns these could be uninitialized, but its ok */
00237         
00238         bicubic_interpolation_color(in, outI, outF, u, v);
00239 }
00240 
00241 /* function assumes out to be zero'ed, only does RGBA */
00242 /* BILINEAR INTERPOLATION */
00243 void bilinear_interpolation_color(struct ImBuf *in, unsigned char *outI, float *outF, float u, float v)
00244 {
00245         float *row1, *row2, *row3, *row4, a, b;
00246         unsigned char *row1I, *row2I, *row3I, *row4I;
00247         float a_b, ma_b, a_mb, ma_mb;
00248         float empty[4]= {0.0f, 0.0f, 0.0f, 0.0f};
00249         unsigned char emptyI[4]= {0, 0, 0, 0};
00250         int y1, y2, x1, x2;
00251         
00252         
00253         /* ImBuf in must have a valid rect or rect_float, assume this is already checked */
00254 
00255         x1= (int)floor(u);
00256         x2= (int)ceil(u);
00257         y1= (int)floor(v);
00258         y2= (int)ceil(v);
00259 
00260         // sample area entirely outside image? 
00261         if (x2<0 || x1>in->x-1 || y2<0 || y1>in->y-1) return;
00262 
00263         if (outF) {
00264                 // sample including outside of edges of image 
00265                 if (x1<0 || y1<0) row1= empty;
00266                 else row1= (float *)in->rect_float + in->x * y1 * 4 + 4*x1;
00267                 
00268                 if (x1<0 || y2>in->y-1) row2= empty;
00269                 else row2= (float *)in->rect_float + in->x * y2 * 4 + 4*x1;
00270                 
00271                 if (x2>in->x-1 || y1<0) row3= empty;
00272                 else row3= (float *)in->rect_float + in->x * y1 * 4 + 4*x2;
00273                 
00274                 if (x2>in->x-1 || y2>in->y-1) row4= empty;
00275                 else row4= (float *)in->rect_float + in->x * y2 * 4 + 4*x2;
00276                 
00277                 a= u-floorf(u);
00278                 b= v-floorf(v);
00279                 a_b= a*b; ma_b= (1.0f-a)*b; a_mb= a*(1.0f-b); ma_mb= (1.0f-a)*(1.0f-b);
00280                 
00281                 outF[0]= ma_mb*row1[0] + a_mb*row3[0] + ma_b*row2[0]+ a_b*row4[0];
00282                 outF[1]= ma_mb*row1[1] + a_mb*row3[1] + ma_b*row2[1]+ a_b*row4[1];
00283                 outF[2]= ma_mb*row1[2] + a_mb*row3[2] + ma_b*row2[2]+ a_b*row4[2];
00284                 outF[3]= ma_mb*row1[3] + a_mb*row3[3] + ma_b*row2[3]+ a_b*row4[3];
00285         }
00286         if (outI) {
00287                 // sample including outside of edges of image 
00288                 if (x1<0 || y1<0) row1I= emptyI;
00289                 else row1I= (unsigned char *)in->rect + in->x * y1 * 4 + 4*x1;
00290                 
00291                 if (x1<0 || y2>in->y-1) row2I= emptyI;
00292                 else row2I= (unsigned char *)in->rect + in->x * y2 * 4 + 4*x1;
00293                 
00294                 if (x2>in->x-1 || y1<0) row3I= emptyI;
00295                 else row3I= (unsigned char *)in->rect + in->x * y1 * 4 + 4*x2;
00296                 
00297                 if (x2>in->x-1 || y2>in->y-1) row4I= emptyI;
00298                 else row4I= (unsigned char *)in->rect + in->x * y2 * 4 + 4*x2;
00299                 
00300                 a= u-floorf(u);
00301                 b= v-floorf(v);
00302                 a_b= a*b; ma_b= (1.0f-a)*b; a_mb= a*(1.0f-b); ma_mb= (1.0f-a)*(1.0f-b);
00303                 
00304                 /* need to add 0.5 to avoid rounding down (causes darken with the smear brush)
00305                  * tested with white images and this should not wrap back to zero */
00306                 outI[0]= (ma_mb*row1I[0] + a_mb*row3I[0] + ma_b*row2I[0]+ a_b*row4I[0]) + 0.5f;
00307                 outI[1]= (ma_mb*row1I[1] + a_mb*row3I[1] + ma_b*row2I[1]+ a_b*row4I[1]) + 0.5f;
00308                 outI[2]= (ma_mb*row1I[2] + a_mb*row3I[2] + ma_b*row2I[2]+ a_b*row4I[2]) + 0.5f;
00309                 outI[3]= (ma_mb*row1I[3] + a_mb*row3I[3] + ma_b*row2I[3]+ a_b*row4I[3]) + 0.5f;
00310         }
00311 }
00312 
00313 /* function assumes out to be zero'ed, only does RGBA */
00314 /* BILINEAR INTERPOLATION */
00315 
00316 /* Note about wrapping, the u/v still needs to be within the image bounds,
00317  * just the interpolation is wrapped.
00318  * This the same as bilinear_interpolation_color except it wraps rather than using empty and emptyI */
00319 void bilinear_interpolation_color_wrap(struct ImBuf *in, unsigned char *outI, float *outF, float u, float v)
00320 {
00321         float *row1, *row2, *row3, *row4, a, b;
00322         unsigned char *row1I, *row2I, *row3I, *row4I;
00323         float a_b, ma_b, a_mb, ma_mb;
00324         int y1, y2, x1, x2;
00325         
00326         
00327         /* ImBuf in must have a valid rect or rect_float, assume this is already checked */
00328 
00329         x1= (int)floor(u);
00330         x2= (int)ceil(u);
00331         y1= (int)floor(v);
00332         y2= (int)ceil(v);
00333 
00334         // sample area entirely outside image? 
00335         if (x2<0 || x1>in->x-1 || y2<0 || y1>in->y-1) return;
00336         
00337         /* wrap interpolation pixels - main difference from bilinear_interpolation_color  */
00338         if(x1<0)x1= in->x+x1;
00339         if(y1<0)y1= in->y+y1;
00340         
00341         if(x2>=in->x)x2= x2-in->x;
00342         if(y2>=in->y)y2= y2-in->y;
00343 
00344         if (outF) {
00345                 // sample including outside of edges of image 
00346                 row1= (float *)in->rect_float + in->x * y1 * 4 + 4*x1;
00347                 row2= (float *)in->rect_float + in->x * y2 * 4 + 4*x1;
00348                 row3= (float *)in->rect_float + in->x * y1 * 4 + 4*x2;
00349                 row4= (float *)in->rect_float + in->x * y2 * 4 + 4*x2;
00350                 
00351                 a= u-floorf(u);
00352                 b= v-floorf(v);
00353                 a_b= a*b; ma_b= (1.0f-a)*b; a_mb= a*(1.0f-b); ma_mb= (1.0f-a)*(1.0f-b);
00354                 
00355                 outF[0]= ma_mb*row1[0] + a_mb*row3[0] + ma_b*row2[0]+ a_b*row4[0];
00356                 outF[1]= ma_mb*row1[1] + a_mb*row3[1] + ma_b*row2[1]+ a_b*row4[1];
00357                 outF[2]= ma_mb*row1[2] + a_mb*row3[2] + ma_b*row2[2]+ a_b*row4[2];
00358                 outF[3]= ma_mb*row1[3] + a_mb*row3[3] + ma_b*row2[3]+ a_b*row4[3];
00359         }
00360         if (outI) {
00361                 // sample including outside of edges of image 
00362                 row1I= (unsigned char *)in->rect + in->x * y1 * 4 + 4*x1;
00363                 row2I= (unsigned char *)in->rect + in->x * y2 * 4 + 4*x1;
00364                 row3I= (unsigned char *)in->rect + in->x * y1 * 4 + 4*x2;
00365                 row4I= (unsigned char *)in->rect + in->x * y2 * 4 + 4*x2;
00366                 
00367                 a= u-floorf(u);
00368                 b= v-floorf(v);
00369                 a_b= a*b; ma_b= (1.0f-a)*b; a_mb= a*(1.0f-b); ma_mb= (1.0f-a)*(1.0f-b);
00370                 
00371                 /* need to add 0.5 to avoid rounding down (causes darken with the smear brush)
00372                  * tested with white images and this should not wrap back to zero */
00373                 outI[0]= (ma_mb*row1I[0] + a_mb*row3I[0] + ma_b*row2I[0]+ a_b*row4I[0]) + 0.5f;
00374                 outI[1]= (ma_mb*row1I[1] + a_mb*row3I[1] + ma_b*row2I[1]+ a_b*row4I[1]) + 0.5f;
00375                 outI[2]= (ma_mb*row1I[2] + a_mb*row3I[2] + ma_b*row2I[2]+ a_b*row4I[2]) + 0.5f;
00376                 outI[3]= (ma_mb*row1I[3] + a_mb*row3I[3] + ma_b*row2I[3]+ a_b*row4I[3]) + 0.5f;
00377         }
00378 }
00379 
00380 void bilinear_interpolation(ImBuf *in, ImBuf *out, float u, float v, int xout, int yout)
00381 {
00382         
00383         unsigned char *outI = NULL;
00384         float *outF = NULL;
00385         
00386         if (in == NULL || (in->rect == NULL && in->rect_float == NULL)) return;
00387         
00388         pixel_from_buffer(out, &outI, &outF, xout, yout); /* gcc warns these could be uninitialized, but its ok */
00389         
00390         bilinear_interpolation_color(in, outI, outF, u, v);
00391 }
00392 
00393 /* function assumes out to be zero'ed, only does RGBA */
00394 /* NEAREST INTERPOLATION */
00395 void neareast_interpolation_color(struct ImBuf *in, unsigned char *outI, float *outF, float u, float v)
00396 {
00397         float *dataF;
00398         unsigned char *dataI;
00399         int y1, x1;
00400 
00401         /* ImBuf in must have a valid rect or rect_float, assume this is already checked */
00402         
00403         x1= (int)(u);
00404         y1= (int)(v);
00405 
00406         // sample area entirely outside image? 
00407         if (x1<0 || x1>in->x-1 || y1<0 || y1>in->y-1) return;
00408         
00409         // sample including outside of edges of image 
00410         if (x1<0 || y1<0) {
00411                 if (outI) {
00412                         outI[0]= 0;
00413                         outI[1]= 0;
00414                         outI[2]= 0;
00415                         outI[3]= 0;
00416                 }
00417                 if (outF) {
00418                         outF[0]= 0.0f;
00419                         outF[1]= 0.0f;
00420                         outF[2]= 0.0f;
00421                         outF[3]= 0.0f;
00422                 }
00423         } else {
00424                 dataI= (unsigned char *)in->rect + in->x * y1 * 4 + 4*x1;
00425                 if (outI) {
00426                         outI[0]= dataI[0];
00427                         outI[1]= dataI[1];
00428                         outI[2]= dataI[2];
00429                         outI[3]= dataI[3];
00430                 }
00431                 dataF= in->rect_float + in->x * y1 * 4 + 4*x1;
00432                 if (outF) {
00433                         outF[0]= dataF[0];
00434                         outF[1]= dataF[1];
00435                         outF[2]= dataF[2];
00436                         outF[3]= dataF[3];
00437                 }
00438         }       
00439 }
00440 
00441 void neareast_interpolation(ImBuf *in, ImBuf *out, float x, float y, int xout, int yout)
00442 {
00443         
00444         unsigned char *outI = NULL;
00445         float *outF = NULL;
00446 
00447         if (in == NULL || (in->rect == NULL && in->rect_float == NULL)) return;
00448         
00449         pixel_from_buffer(out, &outI, &outF, xout, yout); /* gcc warns these could be uninitialized, but its ok */
00450         
00451         neareast_interpolation_color(in, outI, outF, x, y);
00452 }