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