1 // Copyright 2011 Google Inc. All Rights Reserved.
2 //
3 // Use of this source code is governed by a BSD-style license
4 // that can be found in the COPYING file in the root of the source
5 // tree. An additional intellectual property rights grant can be found
6 // in the file PATENTS. All contributing project authors may
7 // be found in the AUTHORS file in the root of the source tree.
8 // -----------------------------------------------------------------------------
9 //
10 // Cost tables for level and modes.
11 //
12 // Author: Skal (pascal.massimino@gmail.com)
13
14 #ifndef WEBP_ENC_COST_H_
15 #define WEBP_ENC_COST_H_
16
17 #include <assert.h>
18 #include <stdlib.h>
19 #include "./vp8enci.h"
20
21 #ifdef __cplusplus
22 extern "C" {
23 #endif
24
25 // On-the-fly info about the current set of residuals. Handy to avoid
26 // passing zillions of params.
27 typedef struct {
28 int first;
29 int last;
30 const int16_t* coeffs;
31
32 int coeff_type;
33 ProbaArray* prob;
34 StatsArray* stats;
35 CostArray* cost;
36 } VP8Residual;
37
38 void VP8InitResidual(int first, int coeff_type,
39 VP8Encoder* const enc, VP8Residual* const res);
40
41 typedef void (*VP8SetResidualCoeffsFunc)(const int16_t* const coeffs,
42 VP8Residual* const res);
43 extern VP8SetResidualCoeffsFunc VP8SetResidualCoeffs;
44
45 void VP8SetResidualCoeffsInit(void); // must be called first
46
47 int VP8RecordCoeffs(int ctx, const VP8Residual* const res);
48
49 // approximate cost per level:
50 extern const uint16_t VP8LevelFixedCosts[MAX_LEVEL + 1];
51 extern const uint16_t VP8EntropyCost[256]; // 8bit fixed-point log(p)
52
53 // Cost of coding one event with probability 'proba'.
VP8BitCost(int bit,uint8_t proba)54 static WEBP_INLINE int VP8BitCost(int bit, uint8_t proba) {
55 return !bit ? VP8EntropyCost[proba] : VP8EntropyCost[255 - proba];
56 }
57
58 // Cost calculation function.
59 typedef int (*VP8GetResidualCostFunc)(int ctx0, const VP8Residual* const res);
60 extern VP8GetResidualCostFunc VP8GetResidualCost;
61
62 void VP8GetResidualCostInit(void); // must be called first
63
64 // Level cost calculations
65 extern const uint16_t VP8LevelCodes[MAX_VARIABLE_LEVEL][2];
66 void VP8CalculateLevelCosts(VP8Proba* const proba);
VP8LevelCost(const uint16_t * const table,int level)67 static WEBP_INLINE int VP8LevelCost(const uint16_t* const table, int level) {
68 return VP8LevelFixedCosts[level]
69 + table[(level > MAX_VARIABLE_LEVEL) ? MAX_VARIABLE_LEVEL : level];
70 }
71
72 // Mode costs
73 extern const uint16_t VP8FixedCostsUV[4];
74 extern const uint16_t VP8FixedCostsI16[4];
75 extern const uint16_t VP8FixedCostsI4[NUM_BMODES][NUM_BMODES][NUM_BMODES];
76
77 //------------------------------------------------------------------------------
78
79 #ifdef __cplusplus
80 } // extern "C"
81 #endif
82
83 #endif /* WEBP_ENC_COST_H_ */
84