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 #include "vp9/common/vp9_common.h"
12 #include "vp9/common/vp9_quant_common.h"
13 #include "vp9/common/vp9_seg_common.h"
14 
15 #if 1
16 static const int16_t dc_qlookup[QINDEX_RANGE] = {
17   4,       8,    8,    9,   10,   11,   12,   12,
18   13,     14,   15,   16,   17,   18,   19,   19,
19   20,     21,   22,   23,   24,   25,   26,   26,
20   27,     28,   29,   30,   31,   32,   32,   33,
21   34,     35,   36,   37,   38,   38,   39,   40,
22   41,     42,   43,   43,   44,   45,   46,   47,
23   48,     48,   49,   50,   51,   52,   53,   53,
24   54,     55,   56,   57,   57,   58,   59,   60,
25   61,     62,   62,   63,   64,   65,   66,   66,
26   67,     68,   69,   70,   70,   71,   72,   73,
27   74,     74,   75,   76,   77,   78,   78,   79,
28   80,     81,   81,   82,   83,   84,   85,   85,
29   87,     88,   90,   92,   93,   95,   96,   98,
30   99,    101,  102,  104,  105,  107,  108,  110,
31   111,   113,  114,  116,  117,  118,  120,  121,
32   123,   125,  127,  129,  131,  134,  136,  138,
33   140,   142,  144,  146,  148,  150,  152,  154,
34   156,   158,  161,  164,  166,  169,  172,  174,
35   177,   180,  182,  185,  187,  190,  192,  195,
36   199,   202,  205,  208,  211,  214,  217,  220,
37   223,   226,  230,  233,  237,  240,  243,  247,
38   250,   253,  257,  261,  265,  269,  272,  276,
39   280,   284,  288,  292,  296,  300,  304,  309,
40   313,   317,  322,  326,  330,  335,  340,  344,
41   349,   354,  359,  364,  369,  374,  379,  384,
42   389,   395,  400,  406,  411,  417,  423,  429,
43   435,   441,  447,  454,  461,  467,  475,  482,
44   489,   497,  505,  513,  522,  530,  539,  549,
45   559,   569,  579,  590,  602,  614,  626,  640,
46   654,   668,  684,  700,  717,  736,  755,  775,
47   796,   819,  843,  869,  896,  925,  955,  988,
48   1022, 1058, 1098, 1139, 1184, 1232, 1282, 1336,
49 };
50 
51 static const int16_t ac_qlookup[QINDEX_RANGE] = {
52   4,       8,    9,   10,   11,   12,   13,   14,
53   15,     16,   17,   18,   19,   20,   21,   22,
54   23,     24,   25,   26,   27,   28,   29,   30,
55   31,     32,   33,   34,   35,   36,   37,   38,
56   39,     40,   41,   42,   43,   44,   45,   46,
57   47,     48,   49,   50,   51,   52,   53,   54,
58   55,     56,   57,   58,   59,   60,   61,   62,
59   63,     64,   65,   66,   67,   68,   69,   70,
60   71,     72,   73,   74,   75,   76,   77,   78,
61   79,     80,   81,   82,   83,   84,   85,   86,
62   87,     88,   89,   90,   91,   92,   93,   94,
63   95,     96,   97,   98,   99,  100,  101,  102,
64   104,   106,  108,  110,  112,  114,  116,  118,
65   120,   122,  124,  126,  128,  130,  132,  134,
66   136,   138,  140,  142,  144,  146,  148,  150,
67   152,   155,  158,  161,  164,  167,  170,  173,
68   176,   179,  182,  185,  188,  191,  194,  197,
69   200,   203,  207,  211,  215,  219,  223,  227,
70   231,   235,  239,  243,  247,  251,  255,  260,
71   265,   270,  275,  280,  285,  290,  295,  300,
72   305,   311,  317,  323,  329,  335,  341,  347,
73   353,   359,  366,  373,  380,  387,  394,  401,
74   408,   416,  424,  432,  440,  448,  456,  465,
75   474,   483,  492,  501,  510,  520,  530,  540,
76   550,   560,  571,  582,  593,  604,  615,  627,
77   639,   651,  663,  676,  689,  702,  715,  729,
78   743,   757,  771,  786,  801,  816,  832,  848,
79   864,   881,  898,  915,  933,  951,  969,  988,
80   1007, 1026, 1046, 1066, 1087, 1108, 1129, 1151,
81   1173, 1196, 1219, 1243, 1267, 1292, 1317, 1343,
82   1369, 1396, 1423, 1451, 1479, 1508, 1537, 1567,
83   1597, 1628, 1660, 1692, 1725, 1759, 1793, 1828,
84 };
85 
vp9_init_quant_tables(void)86 void vp9_init_quant_tables(void) { }
87 #else
88 static int16_t dc_qlookup[QINDEX_RANGE];
89 static int16_t ac_qlookup[QINDEX_RANGE];
90 
91 #define ACDC_MIN 8
92 
93 // TODO(dkovalev) move to common and reuse
poly3(double a,double b,double c,double d,double x)94 static double poly3(double a, double b, double c, double d, double x) {
95   return a*x*x*x + b*x*x + c*x + d;
96 }
97 
vp9_init_quant_tables()98 void vp9_init_quant_tables() {
99   int i, val = 4;
100 
101   // A "real" q of 1.0 forces lossless mode.
102   // In practice non lossless Q's between 1.0 and 2.0 (represented here by
103   // integer values from 5-7 give poor rd results (lower psnr and often
104   // larger size than the lossless encode. To block out those "not very useful"
105   // values we increment the ac and dc q lookup values by 4 after position 0.
106   ac_qlookup[0] = val;
107   dc_qlookup[0] = val;
108   val += 4;
109 
110   for (i = 1; i < QINDEX_RANGE; i++) {
111     const int ac_val = val;
112 
113     val = (int)(val * 1.01975);
114     if (val == ac_val)
115       ++val;
116 
117     ac_qlookup[i] = (int16_t)ac_val;
118     dc_qlookup[i] = (int16_t)MAX(ACDC_MIN, poly3(0.000000305, -0.00065, 0.9,
119                                                  0.5, ac_val));
120   }
121 }
122 #endif
123 
vp9_dc_quant(int qindex,int delta)124 int16_t vp9_dc_quant(int qindex, int delta) {
125   return dc_qlookup[clamp(qindex + delta, 0, MAXQ)];
126 }
127 
vp9_ac_quant(int qindex,int delta)128 int16_t vp9_ac_quant(int qindex, int delta) {
129   return ac_qlookup[clamp(qindex + delta, 0, MAXQ)];
130 }
131 
132 
vp9_get_qindex(const struct segmentation * seg,int segment_id,int base_qindex)133 int vp9_get_qindex(const struct segmentation *seg, int segment_id,
134                    int base_qindex) {
135   if (vp9_segfeature_active(seg, segment_id, SEG_LVL_ALT_Q)) {
136     const int data = vp9_get_segdata(seg, segment_id, SEG_LVL_ALT_Q);
137     const int seg_qindex = seg->abs_delta == SEGMENT_ABSDATA ?
138         data : base_qindex + data;
139     return clamp(seg_qindex, 0, MAXQ);
140   } else {
141     return base_qindex;
142   }
143 }
144 
145