libavcodec/ppc/mpegvideo_altivec.c

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00001 /*
00002  * Copyright (c) 2002 Dieter Shirley
00003  *
00004  * dct_unquantize_h263_altivec:
00005  * Copyright (c) 2003 Romain Dolbeau <romain@dolbeau.org>
00006  *
00007  * This file is part of FFmpeg.
00008  *
00009  * FFmpeg is free software; you can redistribute it and/or
00010  * modify it under the terms of the GNU Lesser General Public
00011  * License as published by the Free Software Foundation; either
00012  * version 2.1 of the License, or (at your option) any later version.
00013  *
00014  * FFmpeg is distributed in the hope that it will be useful,
00015  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00016  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
00017  * Lesser General Public License for more details.
00018  *
00019  * You should have received a copy of the GNU Lesser General Public
00020  * License along with FFmpeg; if not, write to the Free Software
00021  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00022  */
00023 
00024 #include <stdlib.h>
00025 #include <stdio.h>
00026 #include "libavcodec/dsputil.h"
00027 #include "libavcodec/mpegvideo.h"
00028 
00029 #include "gcc_fixes.h"
00030 
00031 #include "dsputil_ppc.h"
00032 #include "util_altivec.h"
00033 // Swaps two variables (used for altivec registers)
00034 #define SWAP(a,b) \
00035 do { \
00036  __typeof__(a) swap_temp=a; \
00037  a=b; \
00038  b=swap_temp; \
00039 } while (0)
00040 
00041 // transposes a matrix consisting of four vectors with four elements each
00042 #define TRANSPOSE4(a,b,c,d) \
00043 do { \
00044  __typeof__(a) _trans_ach = vec_mergeh(a, c); \
00045  __typeof__(a) _trans_acl = vec_mergel(a, c); \
00046  __typeof__(a) _trans_bdh = vec_mergeh(b, d); \
00047  __typeof__(a) _trans_bdl = vec_mergel(b, d); \
00048  \
00049  a = vec_mergeh(_trans_ach, _trans_bdh); \
00050  b = vec_mergel(_trans_ach, _trans_bdh); \
00051  c = vec_mergeh(_trans_acl, _trans_bdl); \
00052  d = vec_mergel(_trans_acl, _trans_bdl); \
00053 } while (0)
00054 
00055 
00056 // Loads a four-byte value (int or float) from the target address
00057 // into every element in the target vector. Only works if the
00058 // target address is four-byte aligned (which should be always).
00059 #define LOAD4(vec, address) \
00060 { \
00061  __typeof__(vec)* _load_addr = (__typeof__(vec)*)(address); \
00062  vector unsigned char _perm_vec = vec_lvsl(0,(address)); \
00063  vec = vec_ld(0, _load_addr); \
00064  vec = vec_perm(vec, vec, _perm_vec); \
00065  vec = vec_splat(vec, 0); \
00066 }
00067 
00068 
00069 #define FOUROF(a) {a,a,a,a}
00070 
00071 int dct_quantize_altivec(MpegEncContext* s,
00072 DCTELEM* data, int n,
00073 int qscale, int* overflow)
00074 {
00075 int lastNonZero;
00076 vector float row0, row1, row2, row3, row4, row5, row6, row7;
00077 vector float alt0, alt1, alt2, alt3, alt4, alt5, alt6, alt7;
00078 const vector float zero = (const vector float)FOUROF(0.);
00079 // used after quantize step
00080 int oldBaseValue = 0;
00081 
00082 // Load the data into the row/alt vectors
00083 {
00084 vector signed short data0, data1, data2, data3, data4, data5, data6, data7;
00085 
00086 data0 = vec_ld(0, data);
00087 data1 = vec_ld(16, data);
00088 data2 = vec_ld(32, data);
00089 data3 = vec_ld(48, data);
00090 data4 = vec_ld(64, data);
00091 data5 = vec_ld(80, data);
00092 data6 = vec_ld(96, data);
00093 data7 = vec_ld(112, data);
00094 
00095 // Transpose the data before we start
00096 TRANSPOSE8(data0, data1, data2, data3, data4, data5, data6, data7);
00097 
00098 // load the data into floating point vectors. We load
00099 // the high half of each row into the main row vectors
00100 // and the low half into the alt vectors.
00101 row0 = vec_ctf(vec_unpackh(data0), 0);
00102 alt0 = vec_ctf(vec_unpackl(data0), 0);
00103 row1 = vec_ctf(vec_unpackh(data1), 0);
00104 alt1 = vec_ctf(vec_unpackl(data1), 0);
00105 row2 = vec_ctf(vec_unpackh(data2), 0);
00106 alt2 = vec_ctf(vec_unpackl(data2), 0);
00107 row3 = vec_ctf(vec_unpackh(data3), 0);
00108 alt3 = vec_ctf(vec_unpackl(data3), 0);
00109 row4 = vec_ctf(vec_unpackh(data4), 0);
00110 alt4 = vec_ctf(vec_unpackl(data4), 0);
00111 row5 = vec_ctf(vec_unpackh(data5), 0);
00112 alt5 = vec_ctf(vec_unpackl(data5), 0);
00113 row6 = vec_ctf(vec_unpackh(data6), 0);
00114 alt6 = vec_ctf(vec_unpackl(data6), 0);
00115 row7 = vec_ctf(vec_unpackh(data7), 0);
00116 alt7 = vec_ctf(vec_unpackl(data7), 0);
00117 }
00118 
00119 // The following block could exist as a separate an altivec dct
00120 // function. However, if we put it inline, the DCT data can remain
00121 // in the vector local variables, as floats, which we'll use during the
00122 // quantize step...
00123 {
00124 const vector float vec_0_298631336 = (vector float)FOUROF(0.298631336f);
00125 const vector float vec_0_390180644 = (vector float)FOUROF(-0.390180644f);
00126 const vector float vec_0_541196100 = (vector float)FOUROF(0.541196100f);
00127 const vector float vec_0_765366865 = (vector float)FOUROF(0.765366865f);
00128 const vector float vec_0_899976223 = (vector float)FOUROF(-0.899976223f);
00129 const vector float vec_1_175875602 = (vector float)FOUROF(1.175875602f);
00130 const vector float vec_1_501321110 = (vector float)FOUROF(1.501321110f);
00131 const vector float vec_1_847759065 = (vector float)FOUROF(-1.847759065f);
00132 const vector float vec_1_961570560 = (vector float)FOUROF(-1.961570560f);
00133 const vector float vec_2_053119869 = (vector float)FOUROF(2.053119869f);
00134 const vector float vec_2_562915447 = (vector float)FOUROF(-2.562915447f);
00135 const vector float vec_3_072711026 = (vector float)FOUROF(3.072711026f);
00136 
00137 
00138 int whichPass, whichHalf;
00139 
00140 for(whichPass = 1; whichPass<=2; whichPass++) {
00141 for(whichHalf = 1; whichHalf<=2; whichHalf++) {
00142 vector float tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7;
00143 vector float tmp10, tmp11, tmp12, tmp13;
00144 vector float z1, z2, z3, z4, z5;
00145 
00146 tmp0 = vec_add(row0, row7); // tmp0 = dataptr[0] + dataptr[7];
00147 tmp7 = vec_sub(row0, row7); // tmp7 = dataptr[0] - dataptr[7];
00148 tmp3 = vec_add(row3, row4); // tmp3 = dataptr[3] + dataptr[4];
00149 tmp4 = vec_sub(row3, row4); // tmp4 = dataptr[3] - dataptr[4];
00150 tmp1 = vec_add(row1, row6); // tmp1 = dataptr[1] + dataptr[6];
00151 tmp6 = vec_sub(row1, row6); // tmp6 = dataptr[1] - dataptr[6];
00152 tmp2 = vec_add(row2, row5); // tmp2 = dataptr[2] + dataptr[5];
00153 tmp5 = vec_sub(row2, row5); // tmp5 = dataptr[2] - dataptr[5];
00154 
00155 tmp10 = vec_add(tmp0, tmp3); // tmp10 = tmp0 + tmp3;
00156 tmp13 = vec_sub(tmp0, tmp3); // tmp13 = tmp0 - tmp3;
00157 tmp11 = vec_add(tmp1, tmp2); // tmp11 = tmp1 + tmp2;
00158 tmp12 = vec_sub(tmp1, tmp2); // tmp12 = tmp1 - tmp2;
00159 
00160 
00161 // dataptr[0] = (DCTELEM) ((tmp10 + tmp11) << PASS1_BITS);
00162 row0 = vec_add(tmp10, tmp11);
00163 
00164 // dataptr[4] = (DCTELEM) ((tmp10 - tmp11) << PASS1_BITS);
00165 row4 = vec_sub(tmp10, tmp11);
00166 
00167 
00168 // z1 = MULTIPLY(tmp12 + tmp13, FIX_0_541196100);
00169 z1 = vec_madd(vec_add(tmp12, tmp13), vec_0_541196100, (vector float)zero);
00170 
00171 // dataptr[2] = (DCTELEM) DESCALE(z1 + MULTIPLY(tmp13, FIX_0_765366865),
00172 // CONST_BITS-PASS1_BITS);
00173 row2 = vec_madd(tmp13, vec_0_765366865, z1);
00174 
00175 // dataptr[6] = (DCTELEM) DESCALE(z1 + MULTIPLY(tmp12, - FIX_1_847759065),
00176 // CONST_BITS-PASS1_BITS);
00177 row6 = vec_madd(tmp12, vec_1_847759065, z1);
00178 
00179 z1 = vec_add(tmp4, tmp7); // z1 = tmp4 + tmp7;
00180 z2 = vec_add(tmp5, tmp6); // z2 = tmp5 + tmp6;
00181 z3 = vec_add(tmp4, tmp6); // z3 = tmp4 + tmp6;
00182 z4 = vec_add(tmp5, tmp7); // z4 = tmp5 + tmp7;
00183 
00184 // z5 = MULTIPLY(z3 + z4, FIX_1_175875602); /* sqrt(2) * c3 */
00185 z5 = vec_madd(vec_add(z3, z4), vec_1_175875602, (vector float)zero);
00186 
00187 // z3 = MULTIPLY(z3, - FIX_1_961570560); /* sqrt(2) * (-c3-c5) */
00188 z3 = vec_madd(z3, vec_1_961570560, z5);
00189 
00190 // z4 = MULTIPLY(z4, - FIX_0_390180644); /* sqrt(2) * (c5-c3) */
00191 z4 = vec_madd(z4, vec_0_390180644, z5);
00192 
00193 // The following adds are rolled into the multiplies above
00194 // z3 = vec_add(z3, z5); // z3 += z5;
00195 // z4 = vec_add(z4, z5); // z4 += z5;
00196 
00197 // z2 = MULTIPLY(z2, - FIX_2_562915447); /* sqrt(2) * (-c1-c3) */
00198 // Wow! It's actually more efficient to roll this multiply
00199 // into the adds below, even thought the multiply gets done twice!
00200 // z2 = vec_madd(z2, vec_2_562915447, (vector float)zero);
00201 
00202 // z1 = MULTIPLY(z1, - FIX_0_899976223); /* sqrt(2) * (c7-c3) */
00203 // Same with this one...
00204 // z1 = vec_madd(z1, vec_0_899976223, (vector float)zero);
00205 
00206 // tmp4 = MULTIPLY(tmp4, FIX_0_298631336); /* sqrt(2) * (-c1+c3+c5-c7) */
00207 // dataptr[7] = (DCTELEM) DESCALE(tmp4 + z1 + z3, CONST_BITS-PASS1_BITS);
00208 row7 = vec_madd(tmp4, vec_0_298631336, vec_madd(z1, vec_0_899976223, z3));
00209 
00210 // tmp5 = MULTIPLY(tmp5, FIX_2_053119869); /* sqrt(2) * ( c1+c3-c5+c7) */
00211 // dataptr[5] = (DCTELEM) DESCALE(tmp5 + z2 + z4, CONST_BITS-PASS1_BITS);
00212 row5 = vec_madd(tmp5, vec_2_053119869, vec_madd(z2, vec_2_562915447, z4));
00213 
00214 // tmp6 = MULTIPLY(tmp6, FIX_3_072711026); /* sqrt(2) * ( c1+c3+c5-c7) */
00215 // dataptr[3] = (DCTELEM) DESCALE(tmp6 + z2 + z3, CONST_BITS-PASS1_BITS);
00216 row3 = vec_madd(tmp6, vec_3_072711026, vec_madd(z2, vec_2_562915447, z3));
00217 
00218 // tmp7 = MULTIPLY(tmp7, FIX_1_501321110); /* sqrt(2) * ( c1+c3-c5-c7) */
00219 // dataptr[1] = (DCTELEM) DESCALE(tmp7 + z1 + z4, CONST_BITS-PASS1_BITS);
00220 row1 = vec_madd(z1, vec_0_899976223, vec_madd(tmp7, vec_1_501321110, z4));
00221 
00222 // Swap the row values with the alts. If this is the first half,
00223 // this sets up the low values to be acted on in the second half.
00224 // If this is the second half, it puts the high values back in
00225 // the row values where they are expected to be when we're done.
00226 SWAP(row0, alt0);
00227 SWAP(row1, alt1);
00228 SWAP(row2, alt2);
00229 SWAP(row3, alt3);
00230 SWAP(row4, alt4);
00231 SWAP(row5, alt5);
00232 SWAP(row6, alt6);
00233 SWAP(row7, alt7);
00234 }
00235 
00236 if (whichPass == 1) {
00237 // transpose the data for the second pass
00238 
00239 // First, block transpose the upper right with lower left.
00240 SWAP(row4, alt0);
00241 SWAP(row5, alt1);
00242 SWAP(row6, alt2);
00243 SWAP(row7, alt3);
00244 
00245 // Now, transpose each block of four
00246 TRANSPOSE4(row0, row1, row2, row3);
00247 TRANSPOSE4(row4, row5, row6, row7);
00248 TRANSPOSE4(alt0, alt1, alt2, alt3);
00249 TRANSPOSE4(alt4, alt5, alt6, alt7);
00250 }
00251 }
00252 }
00253 
00254 // perform the quantize step, using the floating point data
00255 // still in the row/alt registers
00256 {
00257 const int* biasAddr;
00258 const vector signed int* qmat;
00259 vector float bias, negBias;
00260 
00261 if (s->mb_intra) {
00262 vector signed int baseVector;
00263 
00264 // We must cache element 0 in the intra case
00265 // (it needs special handling).
00266 baseVector = vec_cts(vec_splat(row0, 0), 0);
00267 vec_ste(baseVector, 0, &oldBaseValue);
00268 
00269 qmat = (vector signed int*)s->q_intra_matrix[qscale];
00270 biasAddr = &(s->intra_quant_bias);
00271 } else {
00272 qmat = (vector signed int*)s->q_inter_matrix[qscale];
00273 biasAddr = &(s->inter_quant_bias);
00274 }
00275 
00276 // Load the bias vector (We add 0.5 to the bias so that we're
00277 // rounding when we convert to int, instead of flooring.)
00278 {
00279 vector signed int biasInt;
00280 const vector float negOneFloat = (vector float)FOUROF(-1.0f);
00281 LOAD4(biasInt, biasAddr);
00282 bias = vec_ctf(biasInt, QUANT_BIAS_SHIFT);
00283 negBias = vec_madd(bias, negOneFloat, zero);
00284 }
00285 
00286 {
00287 vector float q0, q1, q2, q3, q4, q5, q6, q7;
00288 
00289 q0 = vec_ctf(qmat[0], QMAT_SHIFT);
00290 q1 = vec_ctf(qmat[2], QMAT_SHIFT);
00291 q2 = vec_ctf(qmat[4], QMAT_SHIFT);
00292 q3 = vec_ctf(qmat[6], QMAT_SHIFT);
00293 q4 = vec_ctf(qmat[8], QMAT_SHIFT);
00294 q5 = vec_ctf(qmat[10], QMAT_SHIFT);
00295 q6 = vec_ctf(qmat[12], QMAT_SHIFT);
00296 q7 = vec_ctf(qmat[14], QMAT_SHIFT);
00297 
00298 row0 = vec_sel(vec_madd(row0, q0, negBias), vec_madd(row0, q0, bias),
00299 vec_cmpgt(row0, zero));
00300 row1 = vec_sel(vec_madd(row1, q1, negBias), vec_madd(row1, q1, bias),
00301 vec_cmpgt(row1, zero));
00302 row2 = vec_sel(vec_madd(row2, q2, negBias), vec_madd(row2, q2, bias),
00303 vec_cmpgt(row2, zero));
00304 row3 = vec_sel(vec_madd(row3, q3, negBias), vec_madd(row3, q3, bias),
00305 vec_cmpgt(row3, zero));
00306 row4 = vec_sel(vec_madd(row4, q4, negBias), vec_madd(row4, q4, bias),
00307 vec_cmpgt(row4, zero));
00308 row5 = vec_sel(vec_madd(row5, q5, negBias), vec_madd(row5, q5, bias),
00309 vec_cmpgt(row5, zero));
00310 row6 = vec_sel(vec_madd(row6, q6, negBias), vec_madd(row6, q6, bias),
00311 vec_cmpgt(row6, zero));
00312 row7 = vec_sel(vec_madd(row7, q7, negBias), vec_madd(row7, q7, bias),
00313 vec_cmpgt(row7, zero));
00314 
00315 q0 = vec_ctf(qmat[1], QMAT_SHIFT);
00316 q1 = vec_ctf(qmat[3], QMAT_SHIFT);
00317 q2 = vec_ctf(qmat[5], QMAT_SHIFT);
00318 q3 = vec_ctf(qmat[7], QMAT_SHIFT);
00319 q4 = vec_ctf(qmat[9], QMAT_SHIFT);
00320 q5 = vec_ctf(qmat[11], QMAT_SHIFT);
00321 q6 = vec_ctf(qmat[13], QMAT_SHIFT);
00322 q7 = vec_ctf(qmat[15], QMAT_SHIFT);
00323 
00324 alt0 = vec_sel(vec_madd(alt0, q0, negBias), vec_madd(alt0, q0, bias),
00325 vec_cmpgt(alt0, zero));
00326 alt1 = vec_sel(vec_madd(alt1, q1, negBias), vec_madd(alt1, q1, bias),
00327 vec_cmpgt(alt1, zero));
00328 alt2 = vec_sel(vec_madd(alt2, q2, negBias), vec_madd(alt2, q2, bias),
00329 vec_cmpgt(alt2, zero));
00330 alt3 = vec_sel(vec_madd(alt3, q3, negBias), vec_madd(alt3, q3, bias),
00331 vec_cmpgt(alt3, zero));
00332 alt4 = vec_sel(vec_madd(alt4, q4, negBias), vec_madd(alt4, q4, bias),
00333 vec_cmpgt(alt4, zero));
00334 alt5 = vec_sel(vec_madd(alt5, q5, negBias), vec_madd(alt5, q5, bias),
00335 vec_cmpgt(alt5, zero));
00336 alt6 = vec_sel(vec_madd(alt6, q6, negBias), vec_madd(alt6, q6, bias),
00337 vec_cmpgt(alt6, zero));
00338 alt7 = vec_sel(vec_madd(alt7, q7, negBias), vec_madd(alt7, q7, bias),
00339 vec_cmpgt(alt7, zero));
00340 }
00341 
00342 
00343 }
00344 
00345 // Store the data back into the original block
00346 {
00347 vector signed short data0, data1, data2, data3, data4, data5, data6, data7;
00348 
00349 data0 = vec_pack(vec_cts(row0, 0), vec_cts(alt0, 0));
00350 data1 = vec_pack(vec_cts(row1, 0), vec_cts(alt1, 0));
00351 data2 = vec_pack(vec_cts(row2, 0), vec_cts(alt2, 0));
00352 data3 = vec_pack(vec_cts(row3, 0), vec_cts(alt3, 0));
00353 data4 = vec_pack(vec_cts(row4, 0), vec_cts(alt4, 0));
00354 data5 = vec_pack(vec_cts(row5, 0), vec_cts(alt5, 0));
00355 data6 = vec_pack(vec_cts(row6, 0), vec_cts(alt6, 0));
00356 data7 = vec_pack(vec_cts(row7, 0), vec_cts(alt7, 0));
00357 
00358 {
00359 // Clamp for overflow
00360 vector signed int max_q_int, min_q_int;
00361 vector signed short max_q, min_q;
00362 
00363 LOAD4(max_q_int, &(s->max_qcoeff));
00364 LOAD4(min_q_int, &(s->min_qcoeff));
00365 
00366 max_q = vec_pack(max_q_int, max_q_int);
00367 min_q = vec_pack(min_q_int, min_q_int);
00368 
00369 data0 = vec_max(vec_min(data0, max_q), min_q);
00370 data1 = vec_max(vec_min(data1, max_q), min_q);
00371 data2 = vec_max(vec_min(data2, max_q), min_q);
00372 data4 = vec_max(vec_min(data4, max_q), min_q);
00373 data5 = vec_max(vec_min(data5, max_q), min_q);
00374 data6 = vec_max(vec_min(data6, max_q), min_q);
00375 data7 = vec_max(vec_min(data7, max_q), min_q);
00376 }
00377 
00378 {
00379 vector bool char zero_01, zero_23, zero_45, zero_67;
00380 vector signed char scanIndexes_01, scanIndexes_23, scanIndexes_45, scanIndexes_67;
00381 vector signed char negOne = vec_splat_s8(-1);
00382 vector signed char* scanPtr =
00383 (vector signed char*)(s->intra_scantable.inverse);
00384 signed char lastNonZeroChar;
00385 
00386 // Determine the largest non-zero index.
00387 zero_01 = vec_pack(vec_cmpeq(data0, (vector signed short)zero),
00388 vec_cmpeq(data1, (vector signed short)zero));
00389 zero_23 = vec_pack(vec_cmpeq(data2, (vector signed short)zero),
00390 vec_cmpeq(data3, (vector signed short)zero));
00391 zero_45 = vec_pack(vec_cmpeq(data4, (vector signed short)zero),
00392 vec_cmpeq(data5, (vector signed short)zero));
00393 zero_67 = vec_pack(vec_cmpeq(data6, (vector signed short)zero),
00394 vec_cmpeq(data7, (vector signed short)zero));
00395 
00396 // 64 biggest values
00397 scanIndexes_01 = vec_sel(scanPtr[0], negOne, zero_01);
00398 scanIndexes_23 = vec_sel(scanPtr[1], negOne, zero_23);
00399 scanIndexes_45 = vec_sel(scanPtr[2], negOne, zero_45);
00400 scanIndexes_67 = vec_sel(scanPtr[3], negOne, zero_67);
00401 
00402 // 32 largest values
00403 scanIndexes_01 = vec_max(scanIndexes_01, scanIndexes_23);
00404 scanIndexes_45 = vec_max(scanIndexes_45, scanIndexes_67);
00405 
00406 // 16 largest values
00407 scanIndexes_01 = vec_max(scanIndexes_01, scanIndexes_45);
00408 
00409 // 8 largest values
00410 scanIndexes_01 = vec_max(vec_mergeh(scanIndexes_01, negOne),
00411 vec_mergel(scanIndexes_01, negOne));
00412 
00413 // 4 largest values
00414 scanIndexes_01 = vec_max(vec_mergeh(scanIndexes_01, negOne),
00415 vec_mergel(scanIndexes_01, negOne));
00416 
00417 // 2 largest values
00418 scanIndexes_01 = vec_max(vec_mergeh(scanIndexes_01, negOne),
00419 vec_mergel(scanIndexes_01, negOne));
00420 
00421 // largest value
00422 scanIndexes_01 = vec_max(vec_mergeh(scanIndexes_01, negOne),
00423 vec_mergel(scanIndexes_01, negOne));
00424 
00425 scanIndexes_01 = vec_splat(scanIndexes_01, 0);
00426 
00427 
00428 vec_ste(scanIndexes_01, 0, &lastNonZeroChar);
00429 
00430 lastNonZero = lastNonZeroChar;
00431 
00432 // While the data is still in vectors we check for the transpose IDCT permute
00433 // and handle it using the vector unit if we can. This is the permute used
00434 // by the altivec idct, so it is common when using the altivec dct.
00435 
00436 if ((lastNonZero > 0) && (s->dsp.idct_permutation_type == FF_TRANSPOSE_IDCT_PERM)) {
00437 TRANSPOSE8(data0, data1, data2, data3, data4, data5, data6, data7);
00438 }
00439 
00440 vec_st(data0, 0, data);
00441 vec_st(data1, 16, data);
00442 vec_st(data2, 32, data);
00443 vec_st(data3, 48, data);
00444 vec_st(data4, 64, data);
00445 vec_st(data5, 80, data);
00446 vec_st(data6, 96, data);
00447 vec_st(data7, 112, data);
00448 }
00449 }
00450 
00451 // special handling of block[0]
00452 if (s->mb_intra) {
00453 if (!s->h263_aic) {
00454 if (n < 4)
00455 oldBaseValue /= s->y_dc_scale;
00456 else
00457 oldBaseValue /= s->c_dc_scale;
00458 }
00459 
00460 // Divide by 8, rounding the result
00461 data[0] = (oldBaseValue + 4) >> 3;
00462 }
00463 
00464 // We handled the transpose permutation above and we don't
00465 // need to permute the "no" permutation case.
00466 if ((lastNonZero > 0) &&
00467 (s->dsp.idct_permutation_type != FF_TRANSPOSE_IDCT_PERM) &&
00468 (s->dsp.idct_permutation_type != FF_NO_IDCT_PERM)) {
00469 ff_block_permute(data, s->dsp.idct_permutation,
00470 s->intra_scantable.scantable, lastNonZero);
00471 }
00472 
00473 return lastNonZero;
00474 }
00475 
00476 /* AltiVec version of dct_unquantize_h263
00477  this code assumes `block' is 16 bytes-aligned */
00478 void dct_unquantize_h263_altivec(MpegEncContext *s,
00479 DCTELEM *block, int n, int qscale)
00480 {
00481 POWERPC_PERF_DECLARE(altivec_dct_unquantize_h263_num, 1);
00482 int i, level, qmul, qadd;
00483 int nCoeffs;
00484 
00485 assert(s->block_last_index[n]>=0);
00486 
00487 POWERPC_PERF_START_COUNT(altivec_dct_unquantize_h263_num, 1);
00488 
00489 qadd = (qscale - 1) | 1;
00490 qmul = qscale << 1;
00491 
00492 if (s->mb_intra) {
00493 if (!s->h263_aic) {
00494 if (n < 4)
00495 block[0] = block[0] * s->y_dc_scale;
00496 else
00497 block[0] = block[0] * s->c_dc_scale;
00498 }else
00499 qadd = 0;
00500 i = 1;
00501 nCoeffs= 63; //does not always use zigzag table
00502 } else {
00503 i = 0;
00504 nCoeffs= s->intra_scantable.raster_end[ s->block_last_index[n] ];
00505 }
00506 
00507 {
00508 register const vector signed short vczero = (const vector signed short)vec_splat_s16(0);
00509 DECLARE_ALIGNED_16(short, qmul8[]) =
00510 {
00511 qmul, qmul, qmul, qmul,
00512 qmul, qmul, qmul, qmul
00513 };
00514 DECLARE_ALIGNED_16(short, qadd8[]) =
00515 {
00516 qadd, qadd, qadd, qadd,
00517 qadd, qadd, qadd, qadd
00518 };
00519 DECLARE_ALIGNED_16(short, nqadd8[]) =
00520 {
00521 -qadd, -qadd, -qadd, -qadd,
00522 -qadd, -qadd, -qadd, -qadd
00523 };
00524 register vector signed short blockv, qmulv, qaddv, nqaddv, temp1;
00525 register vector bool short blockv_null, blockv_neg;
00526 register short backup_0 = block[0];
00527 register int j = 0;
00528 
00529 qmulv = vec_ld(0, qmul8);
00530 qaddv = vec_ld(0, qadd8);
00531 nqaddv = vec_ld(0, nqadd8);
00532 
00533 #if 0 // block *is* 16 bytes-aligned, it seems.
00534 // first make sure block[j] is 16 bytes-aligned
00535 for(j = 0; (j <= nCoeffs) && ((((unsigned long)block) + (j << 1)) & 0x0000000F) ; j++) {
00536 level = block[j];
00537 if (level) {
00538 if (level < 0) {
00539 level = level * qmul - qadd;
00540 } else {
00541 level = level * qmul + qadd;
00542 }
00543 block[j] = level;
00544 }
00545 }
00546 #endif
00547 
00548 // vectorize all the 16 bytes-aligned blocks
00549 // of 8 elements
00550 for(; (j + 7) <= nCoeffs ; j+=8) {
00551 blockv = vec_ld(j << 1, block);
00552 blockv_neg = vec_cmplt(blockv, vczero);
00553 blockv_null = vec_cmpeq(blockv, vczero);
00554 // choose between +qadd or -qadd as the third operand
00555 temp1 = vec_sel(qaddv, nqaddv, blockv_neg);
00556 // multiply & add (block{i,i+7} * qmul [+-] qadd)
00557 temp1 = vec_mladd(blockv, qmulv, temp1);
00558 // put 0 where block[{i,i+7} used to have 0
00559 blockv = vec_sel(temp1, blockv, blockv_null);
00560 vec_st(blockv, j << 1, block);
00561 }
00562 
00563 // if nCoeffs isn't a multiple of 8, finish the job
00564 // using good old scalar units.
00565 // (we could do it using a truncated vector,
00566 // but I'm not sure it's worth the hassle)
00567 for(; j <= nCoeffs ; j++) {
00568 level = block[j];
00569 if (level) {
00570 if (level < 0) {
00571 level = level * qmul - qadd;
00572 } else {
00573 level = level * qmul + qadd;
00574 }
00575 block[j] = level;
00576 }
00577 }
00578 
00579 if (i == 1) {
00580 // cheat. this avoid special-casing the first iteration
00581 block[0] = backup_0;
00582 }
00583 }
00584 POWERPC_PERF_STOP_COUNT(altivec_dct_unquantize_h263_num, nCoeffs == 63);
00585 }
00586 
00587 
00588 void idct_put_altivec(uint8_t *dest, int line_size, int16_t *block);
00589 void idct_add_altivec(uint8_t *dest, int line_size, int16_t *block);
00590 
00591 void MPV_common_init_altivec(MpegEncContext *s)
00592 {
00593 if ((mm_flags & FF_MM_ALTIVEC) == 0) return;
00594 
00595 if (s->avctx->lowres==0) {
00596 if ((s->avctx->idct_algo == FF_IDCT_AUTO) ||
00597 (s->avctx->idct_algo == FF_IDCT_ALTIVEC)) {
00598 s->dsp.idct_put = idct_put_altivec;
00599 s->dsp.idct_add = idct_add_altivec;
00600 s->dsp.idct_permutation_type = FF_TRANSPOSE_IDCT_PERM;
00601 }
00602 }
00603 
00604 // Test to make sure that the dct required alignments are met.
00605 if ((((long)(s->q_intra_matrix) & 0x0f) != 0) ||
00606 (((long)(s->q_inter_matrix) & 0x0f) != 0)) {
00607 av_log(s->avctx, AV_LOG_INFO, "Internal Error: q-matrix blocks must be 16-byte aligned "
00608 "to use AltiVec DCT. Reverting to non-AltiVec version.\n");
00609 return;
00610 }
00611 
00612 if (((long)(s->intra_scantable.inverse) & 0x0f) != 0) {
00613 av_log(s->avctx, AV_LOG_INFO, "Internal Error: scan table blocks must be 16-byte aligned "
00614 "to use AltiVec DCT. Reverting to non-AltiVec version.\n");
00615 return;
00616 }
00617 
00618 
00619 if ((s->avctx->dct_algo == FF_DCT_AUTO) ||
00620 (s->avctx->dct_algo == FF_DCT_ALTIVEC)) {
00621 #if 0 /* seems to cause trouble under some circumstances */
00622 s->dct_quantize = dct_quantize_altivec;
00623 #endif
00624 s->dct_unquantize_h263_intra = dct_unquantize_h263_altivec;
00625 s->dct_unquantize_h263_inter = dct_unquantize_h263_altivec;
00626 }
00627 }

Generated on Fri Oct 26 02:35:38 2012 for FFmpeg by doxygen 1.5.8

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