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
22extern "C" {
23#endif
24
25// On-the-fly info about the current set of residuals. Handy to avoid
26// passing zillions of params.
27typedef 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
38void VP8InitResidual(int first, int coeff_type,
39                     VP8Encoder* const enc, VP8Residual* const res);
40
41typedef void (*VP8SetResidualCoeffsFunc)(const int16_t* const coeffs,
42                                         VP8Residual* const res);
43extern VP8SetResidualCoeffsFunc VP8SetResidualCoeffs;
44
45extern void VP8SetResidualCoeffsInit(void);  // must be called first
46
47int VP8RecordCoeffs(int ctx, const VP8Residual* const res);
48
49// approximate cost per level:
50extern const uint16_t VP8LevelFixedCosts[MAX_LEVEL + 1];
51extern const uint16_t VP8EntropyCost[256];        // 8bit fixed-point log(p)
52
53// Cost of coding one event with probability 'proba'.
54static WEBP_INLINE int VP8BitCost(int bit, uint8_t proba) {
55  return !bit ? VP8EntropyCost[proba] : VP8EntropyCost[255 - proba];
56}
57
58// Cost calculation function.
59typedef int (*VP8GetResidualCostFunc)(int ctx0, const VP8Residual* const res);
60extern VP8GetResidualCostFunc VP8GetResidualCost;
61
62extern void VP8GetResidualCostInit(void);  // must be called first
63
64// Level cost calculations
65extern const uint16_t VP8LevelCodes[MAX_VARIABLE_LEVEL][2];
66void VP8CalculateLevelCosts(VP8Proba* const proba);
67static 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
73extern const uint16_t VP8FixedCostsUV[4];
74extern const uint16_t VP8FixedCostsI16[4];
75extern 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