1 : /*
2 : * Copyright (c) 2010 The WebM project authors. All Rights Reserved.
3 : *
4 : * Use of this source code is governed by a BSD-style license
5 : * that can be found in the LICENSE file in the root of the source
6 : * tree. An additional intellectual property rights grant can be found
7 : * in the file PATENTS. All contributing project authors may
8 : * be found in the AUTHORS file in the root of the source tree.
9 : */
10 :
11 :
12 : #include "quant_common.h"
13 :
14 : static const int dc_qlookup[QINDEX_RANGE] =
15 : {
16 : 4, 5, 6, 7, 8, 9, 10, 10, 11, 12, 13, 14, 15, 16, 17, 17,
17 : 18, 19, 20, 20, 21, 21, 22, 22, 23, 23, 24, 25, 25, 26, 27, 28,
18 : 29, 30, 31, 32, 33, 34, 35, 36, 37, 37, 38, 39, 40, 41, 42, 43,
19 : 44, 45, 46, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58,
20 : 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74,
21 : 75, 76, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89,
22 : 91, 93, 95, 96, 98, 100, 101, 102, 104, 106, 108, 110, 112, 114, 116, 118,
23 : 122, 124, 126, 128, 130, 132, 134, 136, 138, 140, 143, 145, 148, 151, 154, 157,
24 : };
25 :
26 : static const int ac_qlookup[QINDEX_RANGE] =
27 : {
28 : 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,
29 : 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35,
30 : 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51,
31 : 52, 53, 54, 55, 56, 57, 58, 60, 62, 64, 66, 68, 70, 72, 74, 76,
32 : 78, 80, 82, 84, 86, 88, 90, 92, 94, 96, 98, 100, 102, 104, 106, 108,
33 : 110, 112, 114, 116, 119, 122, 125, 128, 131, 134, 137, 140, 143, 146, 149, 152,
34 : 155, 158, 161, 164, 167, 170, 173, 177, 181, 185, 189, 193, 197, 201, 205, 209,
35 : 213, 217, 221, 225, 229, 234, 239, 245, 249, 254, 259, 264, 269, 274, 279, 284,
36 : };
37 :
38 :
39 0 : int vp8_dc_quant(int QIndex, int Delta)
40 : {
41 : int retval;
42 :
43 0 : QIndex = QIndex + Delta;
44 :
45 0 : if (QIndex > 127)
46 0 : QIndex = 127;
47 0 : else if (QIndex < 0)
48 0 : QIndex = 0;
49 :
50 0 : retval = dc_qlookup[ QIndex ];
51 0 : return retval;
52 : }
53 :
54 0 : int vp8_dc2quant(int QIndex, int Delta)
55 : {
56 : int retval;
57 :
58 0 : QIndex = QIndex + Delta;
59 :
60 0 : if (QIndex > 127)
61 0 : QIndex = 127;
62 0 : else if (QIndex < 0)
63 0 : QIndex = 0;
64 :
65 0 : retval = dc_qlookup[ QIndex ] * 2;
66 0 : return retval;
67 :
68 : }
69 0 : int vp8_dc_uv_quant(int QIndex, int Delta)
70 : {
71 : int retval;
72 :
73 0 : QIndex = QIndex + Delta;
74 :
75 0 : if (QIndex > 127)
76 0 : QIndex = 127;
77 0 : else if (QIndex < 0)
78 0 : QIndex = 0;
79 :
80 0 : retval = dc_qlookup[ QIndex ];
81 :
82 0 : if (retval > 132)
83 0 : retval = 132;
84 :
85 0 : return retval;
86 : }
87 :
88 0 : int vp8_ac_yquant(int QIndex)
89 : {
90 : int retval;
91 :
92 0 : if (QIndex > 127)
93 0 : QIndex = 127;
94 0 : else if (QIndex < 0)
95 0 : QIndex = 0;
96 :
97 0 : retval = ac_qlookup[ QIndex ];
98 0 : return retval;
99 : }
100 :
101 0 : int vp8_ac2quant(int QIndex, int Delta)
102 : {
103 : int retval;
104 :
105 0 : QIndex = QIndex + Delta;
106 :
107 0 : if (QIndex > 127)
108 0 : QIndex = 127;
109 0 : else if (QIndex < 0)
110 0 : QIndex = 0;
111 :
112 0 : retval = (ac_qlookup[ QIndex ] * 155) / 100;
113 :
114 0 : if (retval < 8)
115 0 : retval = 8;
116 :
117 0 : return retval;
118 : }
119 0 : int vp8_ac_uv_quant(int QIndex, int Delta)
120 : {
121 : int retval;
122 :
123 0 : QIndex = QIndex + Delta;
124 :
125 0 : if (QIndex > 127)
126 0 : QIndex = 127;
127 0 : else if (QIndex < 0)
128 0 : QIndex = 0;
129 :
130 0 : retval = ac_qlookup[ QIndex ];
131 0 : return retval;
132 : }
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