2 * Alpha optimized DSP utils
3 * Copyright (c) 2002 Falk Hueffner <falk@debian.org>
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this library; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 #include "../dsputil.h"
22 #include "../mpegvideo.h"
24 static void dct_unquantize_h263_axp(MpegEncContext *s, DCTELEM *block,
30 DCTELEM *orig_block = block;
33 qadd = WORD_VEC((qscale - 1) | 1);
35 /* This mask kills spill from negative subwords to the next subword. */
36 correction = WORD_VEC((qmul - 1) + 1); /* multiplication / addition */
41 block0 = block[0] * s->y_dc_scale;
43 block0 = block[0] * s->c_dc_scale;
47 n_coeffs = 63; // does not always use zigzag table
49 n_coeffs = s->intra_scantable.raster_end[s->block_last_index[n]];
52 for(i = 0; i <= n_coeffs; block += 4, i += 4) {
53 uint64_t levels, negmask, zeros, add;
60 /* I don't think the speed difference justifies runtime
63 negmask = maxsw4(levels, -1); /* negative -> ffff (-1) */
64 negmask = minsw4(negmask, 0); /* positive -> 0000 (0) */
66 negmask = cmpbge(WORD_VEC(0x7fff), levels);
67 negmask &= (negmask >> 1) | (1 << 7);
68 negmask = zap(-1, negmask);
71 zeros = cmpbge(0, levels);
73 /* zeros |= zeros << 1 is not needed since qadd <= 255, so
74 zapping the lower byte suffices. */
77 levels -= correction & (negmask << 16);
79 /* Negate qadd for negative levels. */
81 add += WORD_VEC(0x0001) & negmask;
82 /* Set qadd to 0 for levels == 0. */
83 add = zap(add, zeros);
90 if (s->mb_intra && !s->h263_aic)
91 orig_block[0] = block0;
94 void MPV_common_init_axp(MpegEncContext *s)
96 s->dct_unquantize_h263 = dct_unquantize_h263_axp;