git.sesse.net Git - ffmpeg/blob - libswscale/internal_bfin.S

   1 /*
   2  * Copyright (C) 2007 Marc Hoffman <marc.hoffman@analog.com>
   3  *                    April 20, 2007
   4  *
   5  * Blackfin Video Color Space Converters Operations
   6  *  convert I420 YV12 to RGB in various formats,
   7  *
   8  * This file is part of FFmpeg.
   9  *
  10  * FFmpeg is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU Lesser General Public
  12  * License as published by the Free Software Foundation; either
  13  * version 2.1 of the License, or (at your option) any later version.
  14  *
  15  * FFmpeg is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18  * Lesser General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU Lesser General Public
  21  * License along with FFmpeg; if not, write to the Free Software
  22  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  23  */
  24
  25
  26 /*
  27     YUV420 to RGB565 conversion.  This routine takes a YUV 420 planar macroblock
  28     and converts it to RGB565.  R:5 bits, G:6 bits, B:5 bits.. packed into shorts
  29
  30
  31     The following calculation is used for the conversion:
  32
  33       r = clipz((y-oy)*cy  + crv*(v-128))
  34       g = clipz((y-oy)*cy  + cgv*(v-128) + cgu*(u-128))
  35       b = clipz((y-oy)*cy  + cbu*(u-128))
  36
  37     y,u,v are pre scaled by a factor of 4 i.e. left shifted to gain precision.
  38
  39
  40     New factorization to elliminate the truncation error which was
  41     occuring due to the byteop3p.
  42
  43
  44   1) use the bytop16m to subtract quad bytes we use this in U8 this
  45    then so the offsets need to be renormalized to 8bits.
  46
  47   2) scale operands up by a factor of 4 not 8 because Blackfin
  48      multiplies include a shift.
  49
  50   3) compute into the accumulators cy*yx0, cy*yx1
  51
  52   4) compute each of the linear equations
  53       r = clipz((y-oy)*cy  + crv*(v-128))
  54
  55       g = clipz((y-oy)*cy  + cgv*(v-128) + cgu*(u-128))
  56
  57       b = clipz((y-oy)*cy  + cbu*(u-128))
  58
  59      reuse of the accumulators requires that we actually multiply
  60      twice once with addition and the second time with a subtaction.
  61
  62      because of this we need to compute the equations in the order R B
  63      then G saving the writes for B in the case of 24/32 bit color
  64      formats.
  65
  66     api: yuv2rgb_kind (uint8_t *Y, uint8_t *U, uint8_t *V, int *out,
  67                        int dW, uint32_t *coeffs);
  68
  69         A          B
  70         ---        ---
  71         i2 = cb    i3 = cr
  72         i1 = coeff i0 = y
  73
  74   Where coeffs have the following layout in memory.
  75
  76   uint32_t oy,oc,zero,cy,crv,rmask,cbu,bmask,cgu,cgv;
  77
  78   coeffs is a pointer to oy.
  79
  80   the {rgb} masks are only utilized by the 565 packing algorithm. Note the data
  81   replication is used to simplify the internal algorithms for the dual mac architecture
  82   of BlackFin.
  83
  84   All routines are exported with _ff_bfin_ as a symbol prefix
  85
  86   rough performance gain compared against -O3:
  87
  88   2779809/1484290 187.28%
  89
  90   which translates to ~33c/pel to ~57c/pel for the reference vs 17.5
  91   c/pel for the optimized implementations. Not sure why there is such a
  92   huge variation on the reference codes on Blackfin I guess it must have
  93   to do with the memory system.
  94
  95 */
  96
  97 #define mL1 .l1.text
  98 #define mL3 .text
  99 #define MEM mL1
 100
 101 #define DEFUN(fname,where,interface) \
 102         .section where;              \
 103         .global _ff_bfin_ ## fname;  \
 104         .type _ff_bfin_ ## fname, STT_FUNC; \
 105         .align 8;                    \
 106         _ff_bfin_ ## fname
 107
 108 #define DEFUN_END(fname) \
 109         .size _ff_bfin_ ## fname, . - _ff_bfin_ ## fname
 110
 111
 112 .text
 113
 114 #define COEFF_LEN        11*4
 115 #define COEFF_REL_CY_OFF 4*4
 116
 117 #define ARG_OUT   20
 118 #define ARG_W     24
 119 #define ARG_COEFF 28
 120
 121 DEFUN(yuv2rgb565_line,MEM,
 122    (uint8_t *Y, uint8_t *U, uint8_t *V, int *out, int dW, uint32_t *coeffs)):
 123         link 0;
 124         [--sp] = (r7:4);
 125         p1 = [fp+ARG_OUT];
 126         r3 = [fp+ARG_W];
 127
 128         i0 = r0;
 129         i2 = r1;
 130         i3 = r2;
 131
 132         r0 = [fp+ARG_COEFF];
 133         i1 = r0;
 134         b1 = i1;
 135         l1 = COEFF_LEN;
 136         m0 = COEFF_REL_CY_OFF;
 137         p0 = r3;
 138
 139         r0   = [i0++];         // 2Y
 140         r1.l = w[i2++];        // 2u
 141         r1.h = w[i3++];        // 2v
 142         p0 = p0>>2;
 143
 144         lsetup (.L0565, .L1565) lc0 = p0;
 145
 146         /*
 147            uint32_t oy,oc,zero,cy,crv,rmask,cbu,bmask,cgu,cgv
 148            r0 -- used to load 4ys
 149            r1 -- used to load 2us,2vs
 150            r4 -- y3,y2
 151            r5 -- y1,y0
 152            r6 -- u1,u0
 153            r7 -- v1,v0
 154         */
 155                                                               r2=[i1++]; // oy
 156 .L0565:
 157         /*
 158         rrrrrrrr gggggggg bbbbbbbb
 159          5432109876543210
 160                     bbbbb >>3
 161               gggggggg    <<3
 162          rrrrrrrr         <<8
 163          rrrrrggggggbbbbb
 164         */
 165         (r4,r5) = byteop16m (r1:0, r3:2)                   || r3=[i1++]; // oc
 166         (r7,r6) = byteop16m (r1:0, r3:2) (r);
 167         r5 = r5 << 2 (v);                                                // y1,y0
 168         r4 = r4 << 2 (v);                                                // y3,y2
 169         r6 = r6 << 2 (v)                                   || r0=[i1++]; // u1,u0, r0=zero
 170         r7 = r7 << 2 (v)                                   || r1=[i1++]; // v1,v0  r1=cy
 171         /* Y' = y*cy */
 172         a1 = r1.h*r5.h, a0 = r1.l*r5.l                     || r1=[i1++]; // crv
 173
 174         /* R = Y+ crv*(Cr-128) */
 175         r2.h = (a1 += r1.h*r7.l), r2.l = (a0 += r1.l*r7.l);
 176                 a1 -= r1.h*r7.l,          a0 -= r1.l*r7.l  || r5=[i1++]; // rmask
 177         r2 = byteop3p(r3:2, r1:0)(LO)                      || r1=[i1++]; // cbu
 178         r2 = r2 >> 3 (v);
 179         r3 = r2 & r5;
 180
 181         /* B = Y+ cbu*(Cb-128) */
 182         r2.h = (a1 += r1.h*r6.l), r2.l = (a0 += r1.l*r6.l);
 183                 a1 -= r1.h*r6.l,          a0 -= r1.l*r6.l  || r5=[i1++]; // bmask
 184         r2 = byteop3p(r3:2, r1:0)(LO)                      || r1=[i1++]; // cgu
 185         r2 = r2 << 8 (v);
 186         r2 = r2 & r5;
 187         r3 = r3 | r2;
 188
 189         /* G = Y+ cgu*(Cb-128)+cgv*(Cr-128) */
 190                 a1 += r1.h*r6.l,          a0 += r1.l*r6.l  || r1=[i1++]; // cgv
 191         r2.h = (a1 += r1.h*r7.l), r2.l = (a0 += r1.l*r7.l);
 192         r2 = byteop3p(r3:2, r1:0)(LO)                      || r5=[i1++m0]; // gmask
 193         r2 = r2 << 3 (v);
 194         r2 = r2 & r5;
 195         r3 = r3 | r2;
 196         [p1++]=r3                                          || r1=[i1++]; // cy
 197
 198         /* Y' = y*cy */
 199
 200         a1 = r1.h*r4.h, a0 = r1.l*r4.l                     || r1=[i1++]; // crv
 201
 202         /* R = Y+ crv*(Cr-128) */
 203         r2.h = (a1 += r1.h*r7.h), r2.l = (a0 += r1.l*r7.h);
 204                 a1 -= r1.h*r7.h,          a0 -= r1.l*r7.h  || r5=[i1++]; // rmask
 205         r2 = byteop3p(r3:2, r1:0)(LO)                      || r1=[i1++]; // cbu
 206         r2 = r2 >> 3 (v);
 207         r3 = r2 & r5;
 208
 209         /* B = Y+ cbu*(Cb-128) */
 210         r2.h = (a1 += r1.h*r6.h), r2.l = (a0 += r1.l*r6.h);
 211                 a1 -= r1.h*r6.h,          a0 -= r1.l*r6.h  || r5=[i1++]; // bmask
 212         r2 = byteop3p(r3:2, r1:0)(LO)                      || r1=[i1++]; // cgu
 213         r2 = r2 << 8 (v);
 214         r2 = r2 & r5;
 215         r3 = r3 | r2;
 216
 217         /* G = Y+ cgu*(Cb-128)+cgv*(Cr-128) */
 218                 a1 += r1.h*r6.h,          a0 += r1.l*r6.h  || r1=[i1++]; // cgv
 219         r2.h = (a1 += r1.h*r7.h), r2.l = (a0 += r1.l*r7.h) || r5=[i1++]; // gmask
 220         r2 = byteop3p(r3:2, r1:0)(LO)                      || r0   =  [i0++];        // 2Y
 221         r2 = r2 << 3 (v)                                   || r1.l = w[i2++];        // 2u
 222         r2 = r2 & r5;
 223         r3 = r3 | r2;
 224         [p1++]=r3                                          || r1.h = w[i3++];        // 2v
 225 .L1565:                                                       r2=[i1++]; // oy
 226
 227         l1 = 0;
 228
 229         (r7:4) = [sp++];
 230         unlink;
 231         rts;
 232 DEFUN_END(yuv2rgb565_line)
 233
 234 DEFUN(yuv2rgb555_line,MEM,
 235    (uint8_t *Y, uint8_t *U, uint8_t *V, int *out, int dW, uint32_t *coeffs)):
 236         link 0;
 237         [--sp] = (r7:4);
 238         p1 = [fp+ARG_OUT];
 239         r3 = [fp+ARG_W];
 240
 241         i0 = r0;
 242         i2 = r1;
 243         i3 = r2;
 244
 245         r0 = [fp+ARG_COEFF];
 246         i1 = r0;
 247         b1 = i1;
 248         l1 = COEFF_LEN;
 249         m0 = COEFF_REL_CY_OFF;
 250         p0 = r3;
 251
 252         r0   = [i0++];         // 2Y
 253         r1.l = w[i2++];        // 2u
 254         r1.h = w[i3++];        // 2v
 255         p0 = p0>>2;
 256
 257         lsetup (.L0555, .L1555) lc0 = p0;
 258
 259         /*
 260            uint32_t oy,oc,zero,cy,crv,rmask,cbu,bmask,cgu,cgv
 261            r0 -- used to load 4ys
 262            r1 -- used to load 2us,2vs
 263            r4 -- y3,y2
 264            r5 -- y1,y0
 265            r6 -- u1,u0
 266            r7 -- v1,v0
 267         */
 268                                                               r2=[i1++]; // oy
 269 .L0555:
 270         /*
 271         rrrrrrrr gggggggg bbbbbbbb
 272          5432109876543210
 273                     bbbbb >>3
 274                gggggggg   <<2
 275           rrrrrrrr        <<7
 276          xrrrrrgggggbbbbb
 277         */
 278
 279         (r4,r5) = byteop16m (r1:0, r3:2)                   || r3=[i1++]; // oc
 280         (r7,r6) = byteop16m (r1:0, r3:2) (r);
 281         r5 = r5 << 2 (v);                                                // y1,y0
 282         r4 = r4 << 2 (v);                                                // y3,y2
 283         r6 = r6 << 2 (v)                                   || r0=[i1++]; // u1,u0, r0=zero
 284         r7 = r7 << 2 (v)                                   || r1=[i1++]; // v1,v0  r1=cy
 285         /* Y' = y*cy */
 286         a1 = r1.h*r5.h, a0 = r1.l*r5.l                     || r1=[i1++]; // crv
 287
 288         /* R = Y+ crv*(Cr-128) */
 289         r2.h = (a1 += r1.h*r7.l), r2.l = (a0 += r1.l*r7.l);
 290                 a1 -= r1.h*r7.l,          a0 -= r1.l*r7.l  || r5=[i1++]; // rmask
 291         r2 = byteop3p(r3:2, r1:0)(LO)                      || r1=[i1++]; // cbu
 292         r2 = r2 >> 3 (v);
 293         r3 = r2 & r5;
 294
 295         /* B = Y+ cbu*(Cb-128) */
 296         r2.h = (a1 += r1.h*r6.l), r2.l = (a0 += r1.l*r6.l);
 297                 a1 -= r1.h*r6.l,          a0 -= r1.l*r6.l  || r5=[i1++]; // bmask
 298         r2 = byteop3p(r3:2, r1:0)(LO)                      || r1=[i1++]; // cgu
 299         r2 = r2 << 7 (v);
 300         r2 = r2 & r5;
 301         r3 = r3 | r2;
 302
 303         /* G = Y+ cgu*(Cb-128)+cgv*(Cr-128) */
 304                 a1 += r1.h*r6.l,          a0 += r1.l*r6.l  || r1=[i1++]; // cgv
 305         r2.h = (a1 += r1.h*r7.l), r2.l = (a0 += r1.l*r7.l);
 306         r2 = byteop3p(r3:2, r1:0)(LO)                      || r5=[i1++m0]; // gmask
 307         r2 = r2 << 2 (v);
 308         r2 = r2 & r5;
 309         r3 = r3 | r2;
 310         [p1++]=r3                                          || r1=[i1++]; // cy
 311
 312         /* Y' = y*cy */
 313
 314         a1 = r1.h*r4.h, a0 = r1.l*r4.l                     || r1=[i1++]; // crv
 315
 316         /* R = Y+ crv*(Cr-128) */
 317         r2.h = (a1 += r1.h*r7.h), r2.l = (a0 += r1.l*r7.h);
 318                 a1 -= r1.h*r7.h,          a0 -= r1.l*r7.h  || r5=[i1++]; // rmask
 319         r2 = byteop3p(r3:2, r1:0)(LO)                      || r1=[i1++]; // cbu
 320         r2 = r2 >> 3 (v);
 321         r3 = r2 & r5;
 322
 323         /* B = Y+ cbu*(Cb-128) */
 324         r2.h = (a1 += r1.h*r6.h), r2.l = (a0 += r1.l*r6.h);
 325                 a1 -= r1.h*r6.h,          a0 -= r1.l*r6.h  || r5=[i1++]; // bmask
 326         r2 = byteop3p(r3:2, r1:0)(LO)                      || r1=[i1++]; // cgu
 327         r2 = r2 << 7 (v);
 328         r2 = r2 & r5;
 329         r3 = r3 | r2;
 330
 331         /* G = Y+ cgu*(Cb-128)+cgv*(Cr-128) */
 332                 a1 += r1.h*r6.h,          a0 += r1.l*r6.h  || r1=[i1++]; // cgv
 333         r2.h = (a1 += r1.h*r7.h), r2.l = (a0 += r1.l*r7.h) || r5=[i1++]; // gmask
 334         r2 = byteop3p(r3:2, r1:0)(LO)                      || r0=[i0++];     // 4Y
 335         r2 = r2 << 2 (v)                                   || r1.l=w[i2++];  // 2u
 336         r2 = r2 & r5;
 337         r3 = r3 | r2;
 338         [p1++]=r3                                          || r1.h=w[i3++]; // 2v
 339
 340 .L1555:                                                       r2=[i1++]; // oy
 341
 342         l1 = 0;
 343
 344         (r7:4) = [sp++];
 345         unlink;
 346         rts;
 347 DEFUN_END(yuv2rgb555_line)
 348
 349 DEFUN(yuv2rgb24_line,MEM,
 350    (uint8_t *Y, uint8_t *U, uint8_t *V, int *out, int dW, uint32_t *coeffs)):
 351         link 0;
 352         [--sp] = (r7:4);
 353         p1 = [fp+ARG_OUT];
 354         r3 = [fp+ARG_W];
 355         p2 = p1;
 356         p2 += 3;
 357
 358         i0 = r0;
 359         i2 = r1;
 360         i3 = r2;
 361
 362         r0 = [fp+ARG_COEFF]; // coeff buffer
 363         i1 = r0;
 364         b1 = i1;
 365         l1 = COEFF_LEN;
 366         m0 = COEFF_REL_CY_OFF;
 367         p0 = r3;
 368
 369         r0   = [i0++];         // 2Y
 370         r1.l = w[i2++];        // 2u
 371         r1.h = w[i3++];        // 2v
 372         p0 = p0>>2;
 373
 374         lsetup (.L0888, .L1888) lc0 = p0;
 375
 376         /*
 377            uint32_t oy,oc,zero,cy,crv,rmask,cbu,bmask,cgu,cgv
 378            r0 -- used to load 4ys
 379            r1 -- used to load 2us,2vs
 380            r4 -- y3,y2
 381            r5 -- y1,y0
 382            r6 -- u1,u0
 383            r7 -- v1,v0
 384         */
 385                                                               r2=[i1++]; // oy
 386 .L0888:
 387         (r4,r5) = byteop16m (r1:0, r3:2)                   || r3=[i1++]; // oc
 388         (r7,r6) = byteop16m (r1:0, r3:2) (r);
 389         r5 = r5 << 2 (v);               // y1,y0
 390         r4 = r4 << 2 (v);               // y3,y2
 391         r6 = r6 << 2 (v) || r0=[i1++];  // u1,u0, r0=zero
 392         r7 = r7 << 2 (v) || r1=[i1++];  // v1,v0  r1=cy
 393
 394         /* Y' = y*cy */
 395         a1 = r1.h*r5.h, a0 = r1.l*r5.l                     || r1=[i1++]; // crv
 396
 397         /* R = Y+ crv*(Cr-128) */
 398         r2.h = (a1 += r1.h*r7.l), r2.l = (a0 += r1.l*r7.l);
 399                 a1 -= r1.h*r7.l,          a0 -= r1.l*r7.l  || r5=[i1++]; // rmask
 400         r2 = byteop3p(r3:2, r1:0)(LO)                      || r1=[i1++]; // cbu
 401         r2=r2>>16 || B[p1++]=r2;
 402                      B[p2++]=r2;
 403
 404         /* B = Y+ cbu*(Cb-128) */
 405         r2.h = (a1 += r1.h*r6.l), r2.l = (a0 += r1.l*r6.l);
 406                 a1 -= r1.h*r6.l,          a0 -= r1.l*r6.l  || r5=[i1++]; // bmask
 407         r3 = byteop3p(r3:2, r1:0)(LO)                      || r1=[i1++]; // cgu
 408
 409         /* G = Y+ cgu*(Cb-128)+cgv*(Cr-128) */
 410                 a1 += r1.h*r6.l,          a0 += r1.l*r6.l  || r1=[i1++]; // cgv
 411         r2.h = (a1 += r1.h*r7.l), r2.l = (a0 += r1.l*r7.l);
 412         r2 = byteop3p(r3:2, r1:0)(LO)                      || r5=[i1++m0]; // gmask, oy,cy,zero
 413
 414         r2=r2>>16 || B[p1++]=r2;
 415                      B[p2++]=r2;
 416
 417         r3=r3>>16 || B[p1++]=r3;
 418                      B[p2++]=r3                            || r1=[i1++]; // cy
 419
 420         p1+=3;
 421         p2+=3;
 422         /* Y' = y*cy */
 423         a1 = r1.h*r4.h, a0 = r1.l*r4.l                     || r1=[i1++]; // crv
 424
 425         /* R = Y+ crv*(Cr-128) */
 426         r2.h = (a1 += r1.h*r7.h), r2.l = (a0 += r1.l*r7.h);
 427                 a1 -= r1.h*r7.h,          a0 -= r1.l*r7.h  || r5=[i1++]; // rmask
 428         r2 = byteop3p(r3:2, r1:0)(LO)                      || r1=[i1++]; // cbu
 429         r2=r2>>16 || B[p1++]=r2;
 430         B[p2++]=r2;
 431
 432         /* B = Y+ cbu*(Cb-128) */
 433         r2.h = (a1 += r1.h*r6.h), r2.l = (a0 += r1.l*r6.h);
 434                 a1 -= r1.h*r6.h,          a0 -= r1.l*r6.h  || r5=[i1++]; // bmask
 435         r3 = byteop3p(r3:2, r1:0)(LO)                      || r1=[i1++]; // cgu
 436
 437         /* G = Y+ cgu*(Cb-128)+cgv*(Cr-128) */
 438                 a1 += r1.h*r6.h,          a0 += r1.l*r6.h  || r1=[i1++]; // cgv
 439         r2.h = (a1 += r1.h*r7.h), r2.l = (a0 += r1.l*r7.h);
 440         r2 = byteop3p(r3:2, r1:0)(LO)                      || r5=[i1++]; // gmask
 441         r2=r2>>16 || B[p1++]=r2 || r0 = [i0++];    // 4y
 442                      B[p2++]=r2 || r1.l = w[i2++]; // 2u
 443         r3=r3>>16 || B[p1++]=r3 || r1.h = w[i3++]; // 2v
 444                      B[p2++]=r3 || r2=[i1++];      // oy
 445
 446         p1+=3;
 447 .L1888: p2+=3;
 448
 449         l1 = 0;
 450
 451         (r7:4) = [sp++];
 452         unlink;
 453         rts;
 454 DEFUN_END(yuv2rgb888_line)