f64fb7472a23837d543b9411855069a83a9d3730
[libav.git] / libavcodec / alpha / mpegvideo_alpha.c
1 /*
2 * Alpha optimized DSP utils
3 * Copyright (c) 2002 Falk Hueffner <falk@debian.org>
4 *
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.
9 *
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.
14 *
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
18 */
19
20 #include "asm.h"
21 #include "../dsputil.h"
22 #include "../mpegvideo.h"
23
24 static void dct_unquantize_h263_intra_axp(MpegEncContext *s, DCTELEM *block,
25 int n, int qscale)
26 {
27 int i, n_coeffs;
28 uint64_t qmul, qadd;
29 uint64_t correction;
30 DCTELEM *orig_block = block;
31 DCTELEM block0;
32
33 qadd = WORD_VEC((qscale - 1) | 1);
34 qmul = qscale << 1;
35 /* This mask kills spill from negative subwords to the next subword. */
36 correction = WORD_VEC((qmul - 1) + 1); /* multiplication / addition */
37
38 if (!s->h263_aic) {
39 if (n < 4)
40 block0 = block[0] * s->y_dc_scale;
41 else
42 block0 = block[0] * s->c_dc_scale;
43 } else {
44 qadd = 0;
45 }
46 n_coeffs = 63; // does not always use zigzag table
47
48 for(i = 0; i <= n_coeffs; block += 4, i += 4) {
49 uint64_t levels, negmask, zeros, add;
50
51 levels = ldq(block);
52 if (levels == 0)
53 continue;
54
55 #ifdef __alpha_max__
56 /* I don't think the speed difference justifies runtime
57 detection. */
58 negmask = maxsw4(levels, -1); /* negative -> ffff (-1) */
59 negmask = minsw4(negmask, 0); /* positive -> 0000 (0) */
60 #else
61 negmask = cmpbge(WORD_VEC(0x7fff), levels);
62 negmask &= (negmask >> 1) | (1 << 7);
63 negmask = zap(-1, negmask);
64 #endif
65
66 zeros = cmpbge(0, levels);
67 zeros &= zeros >> 1;
68 /* zeros |= zeros << 1 is not needed since qadd <= 255, so
69 zapping the lower byte suffices. */
70
71 levels *= qmul;
72 levels -= correction & (negmask << 16);
73
74 /* Negate qadd for negative levels. */
75 add = qadd ^ negmask;
76 add += WORD_VEC(0x0001) & negmask;
77 /* Set qadd to 0 for levels == 0. */
78 add = zap(add, zeros);
79
80 levels += add;
81
82 stq(levels, block);
83 }
84
85 if (s->mb_intra && !s->h263_aic)
86 orig_block[0] = block0;
87 }
88
89 static void dct_unquantize_h263_inter_axp(MpegEncContext *s, DCTELEM *block,
90 int n, int qscale)
91 {
92 int i, n_coeffs;
93 uint64_t qmul, qadd;
94 uint64_t correction;
95 DCTELEM *orig_block = block;
96 DCTELEM block0;
97
98 qadd = WORD_VEC((qscale - 1) | 1);
99 qmul = qscale << 1;
100 /* This mask kills spill from negative subwords to the next subword. */
101 correction = WORD_VEC((qmul - 1) + 1); /* multiplication / addition */
102
103 n_coeffs = s->intra_scantable.raster_end[s->block_last_index[n]];
104
105 for(i = 0; i <= n_coeffs; block += 4, i += 4) {
106 uint64_t levels, negmask, zeros, add;
107
108 levels = ldq(block);
109 if (levels == 0)
110 continue;
111
112 #ifdef __alpha_max__
113 /* I don't think the speed difference justifies runtime
114 detection. */
115 negmask = maxsw4(levels, -1); /* negative -> ffff (-1) */
116 negmask = minsw4(negmask, 0); /* positive -> 0000 (0) */
117 #else
118 negmask = cmpbge(WORD_VEC(0x7fff), levels);
119 negmask &= (negmask >> 1) | (1 << 7);
120 negmask = zap(-1, negmask);
121 #endif
122
123 zeros = cmpbge(0, levels);
124 zeros &= zeros >> 1;
125 /* zeros |= zeros << 1 is not needed since qadd <= 255, so
126 zapping the lower byte suffices. */
127
128 levels *= qmul;
129 levels -= correction & (negmask << 16);
130
131 /* Negate qadd for negative levels. */
132 add = qadd ^ negmask;
133 add += WORD_VEC(0x0001) & negmask;
134 /* Set qadd to 0 for levels == 0. */
135 add = zap(add, zeros);
136
137 levels += add;
138
139 stq(levels, block);
140 }
141 }
142
143 void MPV_common_init_axp(MpegEncContext *s)
144 {
145 s->dct_unquantize_h263_intra = dct_unquantize_h263_intra_axp;
146 s->dct_unquantize_h263_inter = dct_unquantize_h263_inter_axp;
147 }