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[libav.git] / libavcodec / ppc / mpegvideo_altivec.c
1 /*
2 * Copyright (c) 2002 Dieter Shirley
3 *
4 * dct_unquantize_h263_altivec:
5 * Copyright (c) 2003 Romain Dolbeau <romain@dolbeau.org>
6 *
7 * This file is part of FFmpeg.
8 *
9 * FFmpeg is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU Lesser General Public
11 * License as published by the Free Software Foundation; either
12 * version 2.1 of the License, or (at your option) any later version.
13 *
14 * FFmpeg is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * Lesser General Public License for more details.
18 *
19 * You should have received a copy of the GNU Lesser General Public
20 * License along with FFmpeg; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22 */
23
24 #include <stdlib.h>
25 #include <stdio.h>
26 #include "dsputil.h"
27 #include "mpegvideo.h"
28
29 #include "gcc_fixes.h"
30
31 #include "dsputil_ppc.h"
32 #include "util_altivec.h"
33 // Swaps two variables (used for altivec registers)
34 #define SWAP(a,b) \
35 do { \
36 __typeof__(a) swap_temp=a; \
37 a=b; \
38 b=swap_temp; \
39 } while (0)
40
41 // transposes a matrix consisting of four vectors with four elements each
42 #define TRANSPOSE4(a,b,c,d) \
43 do { \
44 __typeof__(a) _trans_ach = vec_mergeh(a, c); \
45 __typeof__(a) _trans_acl = vec_mergel(a, c); \
46 __typeof__(a) _trans_bdh = vec_mergeh(b, d); \
47 __typeof__(a) _trans_bdl = vec_mergel(b, d); \
48 \
49 a = vec_mergeh(_trans_ach, _trans_bdh); \
50 b = vec_mergel(_trans_ach, _trans_bdh); \
51 c = vec_mergeh(_trans_acl, _trans_bdl); \
52 d = vec_mergel(_trans_acl, _trans_bdl); \
53 } while (0)
54
55
56 // Loads a four-byte value (int or float) from the target address
57 // into every element in the target vector. Only works if the
58 // target address is four-byte aligned (which should be always).
59 #define LOAD4(vec, address) \
60 { \
61 __typeof__(vec)* _load_addr = (__typeof__(vec)*)(address); \
62 vector unsigned char _perm_vec = vec_lvsl(0,(address)); \
63 vec = vec_ld(0, _load_addr); \
64 vec = vec_perm(vec, vec, _perm_vec); \
65 vec = vec_splat(vec, 0); \
66 }
67
68
69 #ifdef __APPLE_CC__
70 #define FOUROF(a) (a)
71 #else
72 // slower, for dumb non-apple GCC
73 #define FOUROF(a) {a,a,a,a}
74 #endif
75 int dct_quantize_altivec(MpegEncContext* s,
76 DCTELEM* data, int n,
77 int qscale, int* overflow)
78 {
79 int lastNonZero;
80 vector float row0, row1, row2, row3, row4, row5, row6, row7;
81 vector float alt0, alt1, alt2, alt3, alt4, alt5, alt6, alt7;
82 const vector float zero = (const vector float)FOUROF(0.);
83 // used after quantize step
84 int oldBaseValue = 0;
85
86 // Load the data into the row/alt vectors
87 {
88 vector signed short data0, data1, data2, data3, data4, data5, data6, data7;
89
90 data0 = vec_ld(0, data);
91 data1 = vec_ld(16, data);
92 data2 = vec_ld(32, data);
93 data3 = vec_ld(48, data);
94 data4 = vec_ld(64, data);
95 data5 = vec_ld(80, data);
96 data6 = vec_ld(96, data);
97 data7 = vec_ld(112, data);
98
99 // Transpose the data before we start
100 TRANSPOSE8(data0, data1, data2, data3, data4, data5, data6, data7);
101
102 // load the data into floating point vectors. We load
103 // the high half of each row into the main row vectors
104 // and the low half into the alt vectors.
105 row0 = vec_ctf(vec_unpackh(data0), 0);
106 alt0 = vec_ctf(vec_unpackl(data0), 0);
107 row1 = vec_ctf(vec_unpackh(data1), 0);
108 alt1 = vec_ctf(vec_unpackl(data1), 0);
109 row2 = vec_ctf(vec_unpackh(data2), 0);
110 alt2 = vec_ctf(vec_unpackl(data2), 0);
111 row3 = vec_ctf(vec_unpackh(data3), 0);
112 alt3 = vec_ctf(vec_unpackl(data3), 0);
113 row4 = vec_ctf(vec_unpackh(data4), 0);
114 alt4 = vec_ctf(vec_unpackl(data4), 0);
115 row5 = vec_ctf(vec_unpackh(data5), 0);
116 alt5 = vec_ctf(vec_unpackl(data5), 0);
117 row6 = vec_ctf(vec_unpackh(data6), 0);
118 alt6 = vec_ctf(vec_unpackl(data6), 0);
119 row7 = vec_ctf(vec_unpackh(data7), 0);
120 alt7 = vec_ctf(vec_unpackl(data7), 0);
121 }
122
123 // The following block could exist as a separate an altivec dct
124 // function. However, if we put it inline, the DCT data can remain
125 // in the vector local variables, as floats, which we'll use during the
126 // quantize step...
127 {
128 const vector float vec_0_298631336 = (vector float)FOUROF(0.298631336f);
129 const vector float vec_0_390180644 = (vector float)FOUROF(-0.390180644f);
130 const vector float vec_0_541196100 = (vector float)FOUROF(0.541196100f);
131 const vector float vec_0_765366865 = (vector float)FOUROF(0.765366865f);
132 const vector float vec_0_899976223 = (vector float)FOUROF(-0.899976223f);
133 const vector float vec_1_175875602 = (vector float)FOUROF(1.175875602f);
134 const vector float vec_1_501321110 = (vector float)FOUROF(1.501321110f);
135 const vector float vec_1_847759065 = (vector float)FOUROF(-1.847759065f);
136 const vector float vec_1_961570560 = (vector float)FOUROF(-1.961570560f);
137 const vector float vec_2_053119869 = (vector float)FOUROF(2.053119869f);
138 const vector float vec_2_562915447 = (vector float)FOUROF(-2.562915447f);
139 const vector float vec_3_072711026 = (vector float)FOUROF(3.072711026f);
140
141
142 int whichPass, whichHalf;
143
144 for(whichPass = 1; whichPass<=2; whichPass++)
145 {
146 for(whichHalf = 1; whichHalf<=2; whichHalf++)
147 {
148 vector float tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7;
149 vector float tmp10, tmp11, tmp12, tmp13;
150 vector float z1, z2, z3, z4, z5;
151
152 tmp0 = vec_add(row0, row7); // tmp0 = dataptr[0] + dataptr[7];
153 tmp7 = vec_sub(row0, row7); // tmp7 = dataptr[0] - dataptr[7];
154 tmp3 = vec_add(row3, row4); // tmp3 = dataptr[3] + dataptr[4];
155 tmp4 = vec_sub(row3, row4); // tmp4 = dataptr[3] - dataptr[4];
156 tmp1 = vec_add(row1, row6); // tmp1 = dataptr[1] + dataptr[6];
157 tmp6 = vec_sub(row1, row6); // tmp6 = dataptr[1] - dataptr[6];
158 tmp2 = vec_add(row2, row5); // tmp2 = dataptr[2] + dataptr[5];
159 tmp5 = vec_sub(row2, row5); // tmp5 = dataptr[2] - dataptr[5];
160
161 tmp10 = vec_add(tmp0, tmp3); // tmp10 = tmp0 + tmp3;
162 tmp13 = vec_sub(tmp0, tmp3); // tmp13 = tmp0 - tmp3;
163 tmp11 = vec_add(tmp1, tmp2); // tmp11 = tmp1 + tmp2;
164 tmp12 = vec_sub(tmp1, tmp2); // tmp12 = tmp1 - tmp2;
165
166
167 // dataptr[0] = (DCTELEM) ((tmp10 + tmp11) << PASS1_BITS);
168 row0 = vec_add(tmp10, tmp11);
169
170 // dataptr[4] = (DCTELEM) ((tmp10 - tmp11) << PASS1_BITS);
171 row4 = vec_sub(tmp10, tmp11);
172
173
174 // z1 = MULTIPLY(tmp12 + tmp13, FIX_0_541196100);
175 z1 = vec_madd(vec_add(tmp12, tmp13), vec_0_541196100, (vector float)zero);
176
177 // dataptr[2] = (DCTELEM) DESCALE(z1 + MULTIPLY(tmp13, FIX_0_765366865),
178 // CONST_BITS-PASS1_BITS);
179 row2 = vec_madd(tmp13, vec_0_765366865, z1);
180
181 // dataptr[6] = (DCTELEM) DESCALE(z1 + MULTIPLY(tmp12, - FIX_1_847759065),
182 // CONST_BITS-PASS1_BITS);
183 row6 = vec_madd(tmp12, vec_1_847759065, z1);
184
185 z1 = vec_add(tmp4, tmp7); // z1 = tmp4 + tmp7;
186 z2 = vec_add(tmp5, tmp6); // z2 = tmp5 + tmp6;
187 z3 = vec_add(tmp4, tmp6); // z3 = tmp4 + tmp6;
188 z4 = vec_add(tmp5, tmp7); // z4 = tmp5 + tmp7;
189
190 // z5 = MULTIPLY(z3 + z4, FIX_1_175875602); /* sqrt(2) * c3 */
191 z5 = vec_madd(vec_add(z3, z4), vec_1_175875602, (vector float)zero);
192
193 // z3 = MULTIPLY(z3, - FIX_1_961570560); /* sqrt(2) * (-c3-c5) */
194 z3 = vec_madd(z3, vec_1_961570560, z5);
195
196 // z4 = MULTIPLY(z4, - FIX_0_390180644); /* sqrt(2) * (c5-c3) */
197 z4 = vec_madd(z4, vec_0_390180644, z5);
198
199 // The following adds are rolled into the multiplies above
200 // z3 = vec_add(z3, z5); // z3 += z5;
201 // z4 = vec_add(z4, z5); // z4 += z5;
202
203 // z2 = MULTIPLY(z2, - FIX_2_562915447); /* sqrt(2) * (-c1-c3) */
204 // Wow! It's actually more effecient to roll this multiply
205 // into the adds below, even thought the multiply gets done twice!
206 // z2 = vec_madd(z2, vec_2_562915447, (vector float)zero);
207
208 // z1 = MULTIPLY(z1, - FIX_0_899976223); /* sqrt(2) * (c7-c3) */
209 // Same with this one...
210 // z1 = vec_madd(z1, vec_0_899976223, (vector float)zero);
211
212 // tmp4 = MULTIPLY(tmp4, FIX_0_298631336); /* sqrt(2) * (-c1+c3+c5-c7) */
213 // dataptr[7] = (DCTELEM) DESCALE(tmp4 + z1 + z3, CONST_BITS-PASS1_BITS);
214 row7 = vec_madd(tmp4, vec_0_298631336, vec_madd(z1, vec_0_899976223, z3));
215
216 // tmp5 = MULTIPLY(tmp5, FIX_2_053119869); /* sqrt(2) * ( c1+c3-c5+c7) */
217 // dataptr[5] = (DCTELEM) DESCALE(tmp5 + z2 + z4, CONST_BITS-PASS1_BITS);
218 row5 = vec_madd(tmp5, vec_2_053119869, vec_madd(z2, vec_2_562915447, z4));
219
220 // tmp6 = MULTIPLY(tmp6, FIX_3_072711026); /* sqrt(2) * ( c1+c3+c5-c7) */
221 // dataptr[3] = (DCTELEM) DESCALE(tmp6 + z2 + z3, CONST_BITS-PASS1_BITS);
222 row3 = vec_madd(tmp6, vec_3_072711026, vec_madd(z2, vec_2_562915447, z3));
223
224 // tmp7 = MULTIPLY(tmp7, FIX_1_501321110); /* sqrt(2) * ( c1+c3-c5-c7) */
225 // dataptr[1] = (DCTELEM) DESCALE(tmp7 + z1 + z4, CONST_BITS-PASS1_BITS);
226 row1 = vec_madd(z1, vec_0_899976223, vec_madd(tmp7, vec_1_501321110, z4));
227
228 // Swap the row values with the alts. If this is the first half,
229 // this sets up the low values to be acted on in the second half.
230 // If this is the second half, it puts the high values back in
231 // the row values where they are expected to be when we're done.
232 SWAP(row0, alt0);
233 SWAP(row1, alt1);
234 SWAP(row2, alt2);
235 SWAP(row3, alt3);
236 SWAP(row4, alt4);
237 SWAP(row5, alt5);
238 SWAP(row6, alt6);
239 SWAP(row7, alt7);
240 }
241
242 if (whichPass == 1)
243 {
244 // transpose the data for the second pass
245
246 // First, block transpose the upper right with lower left.
247 SWAP(row4, alt0);
248 SWAP(row5, alt1);
249 SWAP(row6, alt2);
250 SWAP(row7, alt3);
251
252 // Now, transpose each block of four
253 TRANSPOSE4(row0, row1, row2, row3);
254 TRANSPOSE4(row4, row5, row6, row7);
255 TRANSPOSE4(alt0, alt1, alt2, alt3);
256 TRANSPOSE4(alt4, alt5, alt6, alt7);
257 }
258 }
259 }
260
261 // perform the quantize step, using the floating point data
262 // still in the row/alt registers
263 {
264 const int* biasAddr;
265 const vector signed int* qmat;
266 vector float bias, negBias;
267
268 if (s->mb_intra)
269 {
270 vector signed int baseVector;
271
272 // We must cache element 0 in the intra case
273 // (it needs special handling).
274 baseVector = vec_cts(vec_splat(row0, 0), 0);
275 vec_ste(baseVector, 0, &oldBaseValue);
276
277 qmat = (vector signed int*)s->q_intra_matrix[qscale];
278 biasAddr = &(s->intra_quant_bias);
279 }
280 else
281 {
282 qmat = (vector signed int*)s->q_inter_matrix[qscale];
283 biasAddr = &(s->inter_quant_bias);
284 }
285
286 // Load the bias vector (We add 0.5 to the bias so that we're
287 // rounding when we convert to int, instead of flooring.)
288 {
289 vector signed int biasInt;
290 const vector float negOneFloat = (vector float)FOUROF(-1.0f);
291 LOAD4(biasInt, biasAddr);
292 bias = vec_ctf(biasInt, QUANT_BIAS_SHIFT);
293 negBias = vec_madd(bias, negOneFloat, zero);
294 }
295
296 {
297 vector float q0, q1, q2, q3, q4, q5, q6, q7;
298
299 q0 = vec_ctf(qmat[0], QMAT_SHIFT);
300 q1 = vec_ctf(qmat[2], QMAT_SHIFT);
301 q2 = vec_ctf(qmat[4], QMAT_SHIFT);
302 q3 = vec_ctf(qmat[6], QMAT_SHIFT);
303 q4 = vec_ctf(qmat[8], QMAT_SHIFT);
304 q5 = vec_ctf(qmat[10], QMAT_SHIFT);
305 q6 = vec_ctf(qmat[12], QMAT_SHIFT);
306 q7 = vec_ctf(qmat[14], QMAT_SHIFT);
307
308 row0 = vec_sel(vec_madd(row0, q0, negBias), vec_madd(row0, q0, bias),
309 vec_cmpgt(row0, zero));
310 row1 = vec_sel(vec_madd(row1, q1, negBias), vec_madd(row1, q1, bias),
311 vec_cmpgt(row1, zero));
312 row2 = vec_sel(vec_madd(row2, q2, negBias), vec_madd(row2, q2, bias),
313 vec_cmpgt(row2, zero));
314 row3 = vec_sel(vec_madd(row3, q3, negBias), vec_madd(row3, q3, bias),
315 vec_cmpgt(row3, zero));
316 row4 = vec_sel(vec_madd(row4, q4, negBias), vec_madd(row4, q4, bias),
317 vec_cmpgt(row4, zero));
318 row5 = vec_sel(vec_madd(row5, q5, negBias), vec_madd(row5, q5, bias),
319 vec_cmpgt(row5, zero));
320 row6 = vec_sel(vec_madd(row6, q6, negBias), vec_madd(row6, q6, bias),
321 vec_cmpgt(row6, zero));
322 row7 = vec_sel(vec_madd(row7, q7, negBias), vec_madd(row7, q7, bias),
323 vec_cmpgt(row7, zero));
324
325 q0 = vec_ctf(qmat[1], QMAT_SHIFT);
326 q1 = vec_ctf(qmat[3], QMAT_SHIFT);
327 q2 = vec_ctf(qmat[5], QMAT_SHIFT);
328 q3 = vec_ctf(qmat[7], QMAT_SHIFT);
329 q4 = vec_ctf(qmat[9], QMAT_SHIFT);
330 q5 = vec_ctf(qmat[11], QMAT_SHIFT);
331 q6 = vec_ctf(qmat[13], QMAT_SHIFT);
332 q7 = vec_ctf(qmat[15], QMAT_SHIFT);
333
334 alt0 = vec_sel(vec_madd(alt0, q0, negBias), vec_madd(alt0, q0, bias),
335 vec_cmpgt(alt0, zero));
336 alt1 = vec_sel(vec_madd(alt1, q1, negBias), vec_madd(alt1, q1, bias),
337 vec_cmpgt(alt1, zero));
338 alt2 = vec_sel(vec_madd(alt2, q2, negBias), vec_madd(alt2, q2, bias),
339 vec_cmpgt(alt2, zero));
340 alt3 = vec_sel(vec_madd(alt3, q3, negBias), vec_madd(alt3, q3, bias),
341 vec_cmpgt(alt3, zero));
342 alt4 = vec_sel(vec_madd(alt4, q4, negBias), vec_madd(alt4, q4, bias),
343 vec_cmpgt(alt4, zero));
344 alt5 = vec_sel(vec_madd(alt5, q5, negBias), vec_madd(alt5, q5, bias),
345 vec_cmpgt(alt5, zero));
346 alt6 = vec_sel(vec_madd(alt6, q6, negBias), vec_madd(alt6, q6, bias),
347 vec_cmpgt(alt6, zero));
348 alt7 = vec_sel(vec_madd(alt7, q7, negBias), vec_madd(alt7, q7, bias),
349 vec_cmpgt(alt7, zero));
350 }
351
352
353 }
354
355 // Store the data back into the original block
356 {
357 vector signed short data0, data1, data2, data3, data4, data5, data6, data7;
358
359 data0 = vec_pack(vec_cts(row0, 0), vec_cts(alt0, 0));
360 data1 = vec_pack(vec_cts(row1, 0), vec_cts(alt1, 0));
361 data2 = vec_pack(vec_cts(row2, 0), vec_cts(alt2, 0));
362 data3 = vec_pack(vec_cts(row3, 0), vec_cts(alt3, 0));
363 data4 = vec_pack(vec_cts(row4, 0), vec_cts(alt4, 0));
364 data5 = vec_pack(vec_cts(row5, 0), vec_cts(alt5, 0));
365 data6 = vec_pack(vec_cts(row6, 0), vec_cts(alt6, 0));
366 data7 = vec_pack(vec_cts(row7, 0), vec_cts(alt7, 0));
367
368 {
369 // Clamp for overflow
370 vector signed int max_q_int, min_q_int;
371 vector signed short max_q, min_q;
372
373 LOAD4(max_q_int, &(s->max_qcoeff));
374 LOAD4(min_q_int, &(s->min_qcoeff));
375
376 max_q = vec_pack(max_q_int, max_q_int);
377 min_q = vec_pack(min_q_int, min_q_int);
378
379 data0 = vec_max(vec_min(data0, max_q), min_q);
380 data1 = vec_max(vec_min(data1, max_q), min_q);
381 data2 = vec_max(vec_min(data2, max_q), min_q);
382 data4 = vec_max(vec_min(data4, max_q), min_q);
383 data5 = vec_max(vec_min(data5, max_q), min_q);
384 data6 = vec_max(vec_min(data6, max_q), min_q);
385 data7 = vec_max(vec_min(data7, max_q), min_q);
386 }
387
388 {
389 vector bool char zero_01, zero_23, zero_45, zero_67;
390 vector signed char scanIndices_01, scanIndices_23, scanIndices_45, scanIndices_67;
391 vector signed char negOne = vec_splat_s8(-1);
392 vector signed char* scanPtr =
393 (vector signed char*)(s->intra_scantable.inverse);
394 signed char lastNonZeroChar;
395
396 // Determine the largest non-zero index.
397 zero_01 = vec_pack(vec_cmpeq(data0, (vector signed short)zero),
398 vec_cmpeq(data1, (vector signed short)zero));
399 zero_23 = vec_pack(vec_cmpeq(data2, (vector signed short)zero),
400 vec_cmpeq(data3, (vector signed short)zero));
401 zero_45 = vec_pack(vec_cmpeq(data4, (vector signed short)zero),
402 vec_cmpeq(data5, (vector signed short)zero));
403 zero_67 = vec_pack(vec_cmpeq(data6, (vector signed short)zero),
404 vec_cmpeq(data7, (vector signed short)zero));
405
406 // 64 biggest values
407 scanIndices_01 = vec_sel(scanPtr[0], negOne, zero_01);
408 scanIndices_23 = vec_sel(scanPtr[1], negOne, zero_23);
409 scanIndices_45 = vec_sel(scanPtr[2], negOne, zero_45);
410 scanIndices_67 = vec_sel(scanPtr[3], negOne, zero_67);
411
412 // 32 largest values
413 scanIndices_01 = vec_max(scanIndices_01, scanIndices_23);
414 scanIndices_45 = vec_max(scanIndices_45, scanIndices_67);
415
416 // 16 largest values
417 scanIndices_01 = vec_max(scanIndices_01, scanIndices_45);
418
419 // 8 largest values
420 scanIndices_01 = vec_max(vec_mergeh(scanIndices_01, negOne),
421 vec_mergel(scanIndices_01, negOne));
422
423 // 4 largest values
424 scanIndices_01 = vec_max(vec_mergeh(scanIndices_01, negOne),
425 vec_mergel(scanIndices_01, negOne));
426
427 // 2 largest values
428 scanIndices_01 = vec_max(vec_mergeh(scanIndices_01, negOne),
429 vec_mergel(scanIndices_01, negOne));
430
431 // largest value
432 scanIndices_01 = vec_max(vec_mergeh(scanIndices_01, negOne),
433 vec_mergel(scanIndices_01, negOne));
434
435 scanIndices_01 = vec_splat(scanIndices_01, 0);
436
437
438 vec_ste(scanIndices_01, 0, &lastNonZeroChar);
439
440 lastNonZero = lastNonZeroChar;
441
442 // While the data is still in vectors we check for the transpose IDCT permute
443 // and handle it using the vector unit if we can. This is the permute used
444 // by the altivec idct, so it is common when using the altivec dct.
445
446 if ((lastNonZero > 0) && (s->dsp.idct_permutation_type == FF_TRANSPOSE_IDCT_PERM))
447 {
448 TRANSPOSE8(data0, data1, data2, data3, data4, data5, data6, data7);
449 }
450
451 vec_st(data0, 0, data);
452 vec_st(data1, 16, data);
453 vec_st(data2, 32, data);
454 vec_st(data3, 48, data);
455 vec_st(data4, 64, data);
456 vec_st(data5, 80, data);
457 vec_st(data6, 96, data);
458 vec_st(data7, 112, data);
459 }
460 }
461
462 // special handling of block[0]
463 if (s->mb_intra)
464 {
465 if (!s->h263_aic)
466 {
467 if (n < 4)
468 oldBaseValue /= s->y_dc_scale;
469 else
470 oldBaseValue /= s->c_dc_scale;
471 }
472
473 // Divide by 8, rounding the result
474 data[0] = (oldBaseValue + 4) >> 3;
475 }
476
477 // We handled the transpose permutation above and we don't
478 // need to permute the "no" permutation case.
479 if ((lastNonZero > 0) &&
480 (s->dsp.idct_permutation_type != FF_TRANSPOSE_IDCT_PERM) &&
481 (s->dsp.idct_permutation_type != FF_NO_IDCT_PERM))
482 {
483 ff_block_permute(data, s->dsp.idct_permutation,
484 s->intra_scantable.scantable, lastNonZero);
485 }
486
487 return lastNonZero;
488 }
489 #undef FOUROF
490
491 /*
492 AltiVec version of dct_unquantize_h263
493 this code assumes `block' is 16 bytes-aligned
494 */
495 void dct_unquantize_h263_altivec(MpegEncContext *s,
496 DCTELEM *block, int n, int qscale)
497 {
498 POWERPC_PERF_DECLARE(altivec_dct_unquantize_h263_num, 1);
499 int i, level, qmul, qadd;
500 int nCoeffs;
501
502 assert(s->block_last_index[n]>=0);
503
504 POWERPC_PERF_START_COUNT(altivec_dct_unquantize_h263_num, 1);
505
506 qadd = (qscale - 1) | 1;
507 qmul = qscale << 1;
508
509 if (s->mb_intra) {
510 if (!s->h263_aic) {
511 if (n < 4)
512 block[0] = block[0] * s->y_dc_scale;
513 else
514 block[0] = block[0] * s->c_dc_scale;
515 }else
516 qadd = 0;
517 i = 1;
518 nCoeffs= 63; //does not always use zigzag table
519 } else {
520 i = 0;
521 nCoeffs= s->intra_scantable.raster_end[ s->block_last_index[n] ];
522 }
523
524 {
525 register const vector signed short vczero = (const vector signed short)vec_splat_s16(0);
526 DECLARE_ALIGNED_16(short, qmul8[]) =
527 {
528 qmul, qmul, qmul, qmul,
529 qmul, qmul, qmul, qmul
530 };
531 DECLARE_ALIGNED_16(short, qadd8[]) =
532 {
533 qadd, qadd, qadd, qadd,
534 qadd, qadd, qadd, qadd
535 };
536 DECLARE_ALIGNED_16(short, nqadd8[]) =
537 {
538 -qadd, -qadd, -qadd, -qadd,
539 -qadd, -qadd, -qadd, -qadd
540 };
541 register vector signed short blockv, qmulv, qaddv, nqaddv, temp1;
542 register vector bool short blockv_null, blockv_neg;
543 register short backup_0 = block[0];
544 register int j = 0;
545
546 qmulv = vec_ld(0, qmul8);
547 qaddv = vec_ld(0, qadd8);
548 nqaddv = vec_ld(0, nqadd8);
549
550 #if 0 // block *is* 16 bytes-aligned, it seems.
551 // first make sure block[j] is 16 bytes-aligned
552 for(j = 0; (j <= nCoeffs) && ((((unsigned long)block) + (j << 1)) & 0x0000000F) ; j++) {
553 level = block[j];
554 if (level) {
555 if (level < 0) {
556 level = level * qmul - qadd;
557 } else {
558 level = level * qmul + qadd;
559 }
560 block[j] = level;
561 }
562 }
563 #endif
564
565 // vectorize all the 16 bytes-aligned blocks
566 // of 8 elements
567 for(; (j + 7) <= nCoeffs ; j+=8)
568 {
569 blockv = vec_ld(j << 1, block);
570 blockv_neg = vec_cmplt(blockv, vczero);
571 blockv_null = vec_cmpeq(blockv, vczero);
572 // choose between +qadd or -qadd as the third operand
573 temp1 = vec_sel(qaddv, nqaddv, blockv_neg);
574 // multiply & add (block{i,i+7} * qmul [+-] qadd)
575 temp1 = vec_mladd(blockv, qmulv, temp1);
576 // put 0 where block[{i,i+7} used to have 0
577 blockv = vec_sel(temp1, blockv, blockv_null);
578 vec_st(blockv, j << 1, block);
579 }
580
581 // if nCoeffs isn't a multiple of 8, finish the job
582 // using good old scalar units.
583 // (we could do it using a truncated vector,
584 // but I'm not sure it's worth the hassle)
585 for(; j <= nCoeffs ; j++) {
586 level = block[j];
587 if (level) {
588 if (level < 0) {
589 level = level * qmul - qadd;
590 } else {
591 level = level * qmul + qadd;
592 }
593 block[j] = level;
594 }
595 }
596
597 if (i == 1)
598 { // cheat. this avoid special-casing the first iteration
599 block[0] = backup_0;
600 }
601 }
602 POWERPC_PERF_STOP_COUNT(altivec_dct_unquantize_h263_num, nCoeffs == 63);
603 }
604
605
606 extern void idct_put_altivec(uint8_t *dest, int line_size, int16_t *block);
607 extern void idct_add_altivec(uint8_t *dest, int line_size, int16_t *block);
608
609 void MPV_common_init_altivec(MpegEncContext *s)
610 {
611 if (s->avctx->lowres==0)
612 {
613 if ((s->avctx->idct_algo == FF_IDCT_AUTO) ||
614 (s->avctx->idct_algo == FF_IDCT_ALTIVEC))
615 {
616 s->dsp.idct_put = idct_put_altivec;
617 s->dsp.idct_add = idct_add_altivec;
618 s->dsp.idct_permutation_type = FF_TRANSPOSE_IDCT_PERM;
619 }
620 }
621
622 // Test to make sure that the dct required alignments are met.
623 if ((((long)(s->q_intra_matrix) & 0x0f) != 0) ||
624 (((long)(s->q_inter_matrix) & 0x0f) != 0))
625 {
626 av_log(s->avctx, AV_LOG_INFO, "Internal Error: q-matrix blocks must be 16-byte aligned "
627 "to use AltiVec DCT. Reverting to non-AltiVec version.\n");
628 return;
629 }
630
631 if (((long)(s->intra_scantable.inverse) & 0x0f) != 0)
632 {
633 av_log(s->avctx, AV_LOG_INFO, "Internal Error: scan table blocks must be 16-byte aligned "
634 "to use AltiVec DCT. Reverting to non-AltiVec version.\n");
635 return;
636 }
637
638
639 if ((s->avctx->dct_algo == FF_DCT_AUTO) ||
640 (s->avctx->dct_algo == FF_DCT_ALTIVEC))
641 {
642 #if 0 /* seems to cause trouble under some circumstances */
643 s->dct_quantize = dct_quantize_altivec;
644 #endif
645 s->dct_unquantize_h263_intra = dct_unquantize_h263_altivec;
646 s->dct_unquantize_h263_inter = dct_unquantize_h263_altivec;
647 }
648 }