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rv34dsp.c
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1 /*
2  * RV30/40 decoder common dsp functions
3  * Copyright (c) 2007 Mike Melanson, Konstantin Shishkov
4  * Copyright (c) 2011 Janne Grunau
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 /**
24  * @file
25  * RV30/40 decoder common dsp functions
26  */
27 #include "dsputil.h"
28 #include "rv34dsp.h"
29 #include "libavutil/common.h"
30 
31 /**
32  * @name RV30/40 inverse transform functions
33  * @{
34  */
35 
37 {
38  int i;
39 
40  for(i = 0; i < 4; i++){
41  const int z0 = 13*(block[i+4*0] + block[i+4*2]);
42  const int z1 = 13*(block[i+4*0] - block[i+4*2]);
43  const int z2 = 7* block[i+4*1] - 17*block[i+4*3];
44  const int z3 = 17* block[i+4*1] + 7*block[i+4*3];
45 
46  temp[4*i+0] = z0 + z3;
47  temp[4*i+1] = z1 + z2;
48  temp[4*i+2] = z1 - z2;
49  temp[4*i+3] = z0 - z3;
50  }
51 }
52 
53 /**
54  * Real Video 3.0/4.0 inverse transform + sample reconstruction
55  * Code is almost the same as in SVQ3, only scaling is different.
56  */
57 static void rv34_idct_add_c(uint8_t *dst, ptrdiff_t stride, DCTELEM *block){
58  int temp[16];
59  int i;
60 
61  rv34_row_transform(temp, block);
62  memset(block, 0, 16*sizeof(DCTELEM));
63 
64  for(i = 0; i < 4; i++){
65  const int z0 = 13*(temp[4*0+i] + temp[4*2+i]) + 0x200;
66  const int z1 = 13*(temp[4*0+i] - temp[4*2+i]) + 0x200;
67  const int z2 = 7* temp[4*1+i] - 17*temp[4*3+i];
68  const int z3 = 17* temp[4*1+i] + 7*temp[4*3+i];
69 
70  dst[0] = av_clip_uint8( dst[0] + ( (z0 + z3) >> 10 ) );
71  dst[1] = av_clip_uint8( dst[1] + ( (z1 + z2) >> 10 ) );
72  dst[2] = av_clip_uint8( dst[2] + ( (z1 - z2) >> 10 ) );
73  dst[3] = av_clip_uint8( dst[3] + ( (z0 - z3) >> 10 ) );
74 
75  dst += stride;
76  }
77 }
78 
79 /**
80  * RealVideo 3.0/4.0 inverse transform for DC block
81  *
82  * Code is almost the same as rv34_inv_transform()
83  * but final coefficients are multiplied by 1.5 and have no rounding.
84  */
86  int temp[16];
87  int i;
88 
89  rv34_row_transform(temp, block);
90 
91  for(i = 0; i < 4; i++){
92  const int z0 = 39*(temp[4*0+i] + temp[4*2+i]);
93  const int z1 = 39*(temp[4*0+i] - temp[4*2+i]);
94  const int z2 = 21* temp[4*1+i] - 51*temp[4*3+i];
95  const int z3 = 51* temp[4*1+i] + 21*temp[4*3+i];
96 
97  block[i*4+0] = (z0 + z3) >> 11;
98  block[i*4+1] = (z1 + z2) >> 11;
99  block[i*4+2] = (z1 - z2) >> 11;
100  block[i*4+3] = (z0 - z3) >> 11;
101  }
102 }
103 
104 static void rv34_idct_dc_add_c(uint8_t *dst, ptrdiff_t stride, int dc)
105 {
106  int i, j;
107 
108  dc = (13*13*dc + 0x200) >> 10;
109  for (i = 0; i < 4; i++)
110  {
111  for (j = 0; j < 4; j++)
112  dst[j] = av_clip_uint8( dst[j] + dc );
113 
114  dst += stride;
115  }
116 }
117 
119 {
120  DCTELEM dc = (13 * 13 * 3 * block[0]) >> 11;
121  int i, j;
122 
123  for (i = 0; i < 4; i++, block += 4)
124  for (j = 0; j < 4; j++)
125  block[j] = dc;
126 }
127 
128 /** @} */ // transform
129 
130 
134 
137 
138  if (ARCH_ARM)
139  ff_rv34dsp_init_arm(c, dsp);
140  if (ARCH_X86)
141  ff_rv34dsp_init_x86(c, dsp);
142 }