1/* 2 * Alpha optimized DSP utils 3 * Copyright (c) 2002 Falk Hueffner <falk@debian.org> 4 * 5 * This file is part of FFmpeg. 6 * 7 * FFmpeg is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU Lesser General Public 9 * License as published by the Free Software Foundation; either 10 * version 2.1 of the License, or (at your option) any later version. 11 * 12 * FFmpeg is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 * Lesser General Public License for more details. 16 * 17 * You should have received a copy of the GNU Lesser General Public 18 * License along with FFmpeg; if not, write to the Free Software 19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 20 */ 21 22#include "libavcodec/dsputil.h" 23#include "libavcodec/mpegvideo.h" 24#include "asm.h" 25 26static void dct_unquantize_h263_axp(DCTELEM *block, int n_coeffs, 27 uint64_t qscale, uint64_t qadd) 28{ 29 uint64_t qmul = qscale << 1; 30 uint64_t correction = WORD_VEC(qmul * 255 >> 8); 31 int i; 32 33 qadd = WORD_VEC(qadd); 34 35 for(i = 0; i <= n_coeffs; block += 4, i += 4) { 36 uint64_t levels, negmask, zeros, add, sub; 37 38 levels = ldq(block); 39 if (levels == 0) 40 continue; 41 42#ifdef __alpha_max__ 43 /* I don't think the speed difference justifies runtime 44 detection. */ 45 negmask = maxsw4(levels, -1); /* negative -> ffff (-1) */ 46 negmask = minsw4(negmask, 0); /* positive -> 0000 (0) */ 47#else 48 negmask = cmpbge(WORD_VEC(0x7fff), levels); 49 negmask &= (negmask >> 1) | (1 << 7); 50 negmask = zap(-1, negmask); 51#endif 52 53 zeros = cmpbge(0, levels); 54 zeros &= zeros >> 1; 55 /* zeros |= zeros << 1 is not needed since qadd <= 255, so 56 zapping the lower byte suffices. */ 57 58 levels *= qmul; 59 levels -= correction & (negmask << 16); 60 61 add = qadd & ~negmask; 62 sub = qadd & negmask; 63 /* Set qadd to 0 for levels == 0. */ 64 add = zap(add, zeros); 65 levels += add; 66 levels -= sub; 67 68 stq(levels, block); 69 } 70} 71 72static void dct_unquantize_h263_intra_axp(MpegEncContext *s, DCTELEM *block, 73 int n, int qscale) 74{ 75 int n_coeffs; 76 uint64_t qadd; 77 DCTELEM block0 = block[0]; 78 79 if (!s->h263_aic) { 80 if (n < 4) 81 block0 *= s->y_dc_scale; 82 else 83 block0 *= s->c_dc_scale; 84 qadd = (qscale - 1) | 1; 85 } else { 86 qadd = 0; 87 } 88 89 if(s->ac_pred) 90 n_coeffs = 63; 91 else 92 n_coeffs = s->inter_scantable.raster_end[s->block_last_index[n]]; 93 94 dct_unquantize_h263_axp(block, n_coeffs, qscale, qadd); 95 96 block[0] = block0; 97} 98 99static void dct_unquantize_h263_inter_axp(MpegEncContext *s, DCTELEM *block, 100 int n, int qscale) 101{ 102 int n_coeffs = s->inter_scantable.raster_end[s->block_last_index[n]]; 103 dct_unquantize_h263_axp(block, n_coeffs, qscale, (qscale - 1) | 1); 104} 105 106void MPV_common_init_axp(MpegEncContext *s) 107{ 108 s->dct_unquantize_h263_intra = dct_unquantize_h263_intra_axp; 109 s->dct_unquantize_h263_inter = dct_unquantize_h263_inter_axp; 110} 111