mpegvideo_mmi.c
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1 /*
2  * Copyright (c) 2000,2001 Fabrice Bellard
3  *
4  * MMI optimization by Leon van Stuivenberg
5  *
6  * This file is part of Libav.
7  *
8  * Libav is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * Libav is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with Libav; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 #include "libavcodec/avcodec.h"
24 #include "libavcodec/dsputil.h"
25 #include "libavcodec/mpegvideo.h"
26 
28  DCTELEM *block, int n, int qscale)
29 {
30  int level=0, qmul, qadd;
31  int nCoeffs;
32 
33  assert(s->block_last_index[n]>=0);
34 
35  qadd = (qscale - 1) | 1;
36  qmul = qscale << 1;
37 
38  if (s->mb_intra) {
39  if (!s->h263_aic) {
40  if (n < 4)
41  level = block[0] * s->y_dc_scale;
42  else
43  level = block[0] * s->c_dc_scale;
44  }else {
45  qadd = 0;
46  level = block[0];
47  }
48  nCoeffs= 63; //does not always use zigzag table
49  } else {
50  nCoeffs= s->intra_scantable.raster_end[ s->block_last_index[n] ];
51  }
52 
53  __asm__ volatile(
54  "add $14, $0, %3 \n\t"
55  "pcpyld $8, %0, %0 \n\t"
56  "pcpyh $8, $8 \n\t" //r8 = qmul
57  "pcpyld $9, %1, %1 \n\t"
58  "pcpyh $9, $9 \n\t" //r9 = qadd
59  ".p2align 2 \n\t"
60  "1: \n\t"
61  "lq $10, 0($14) \n\t" //r10 = level
62  "addi $14, $14, 16 \n\t" //block+=8
63  "addi %2, %2, -8 \n\t"
64  "pcgth $11, $0, $10 \n\t" //r11 = level < 0 ? -1 : 0
65  "pcgth $12, $10, $0 \n\t" //r12 = level > 0 ? -1 : 0
66  "por $12, $11, $12 \n\t"
67  "pmulth $10, $10, $8 \n\t"
68  "paddh $13, $9, $11 \n\t"
69  "pxor $13, $13, $11 \n\t" //r13 = level < 0 ? -qadd : qadd
70  "pmfhl.uw $11 \n\t"
71  "pinteh $10, $11, $10 \n\t" //r10 = level * qmul
72  "paddh $10, $10, $13 \n\t"
73  "pand $10, $10, $12 \n\t"
74  "sq $10, -16($14) \n\t"
75  "bgez %2, 1b \n\t"
76  :: "r"(qmul), "r" (qadd), "r" (nCoeffs), "r" (block) : "$8", "$9", "$10", "$11", "$12", "$13", "$14", "memory" );
77 
78  if(s->mb_intra)
79  block[0]= level;
80 }
81 
82 
84 {
87 }
88 
89