cost.h revision eb525c5499e34cc9c4b825d6d9e75bb07cc06ace 
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 "./vp8enci.h"
18
19#if defined(__cplusplus) || defined(c_plusplus)
20extern "C" {
21#endif
22
23// approximate cost per level:
24extern const uint16_t VP8LevelFixedCosts[MAX_LEVEL + 1];
25extern const uint16_t VP8EntropyCost[256];        // 8bit fixed-point log(p)
26
27// Cost of coding one event with probability 'proba'.
28static WEBP_INLINE int VP8BitCost(int bit, uint8_t proba) {
29  return !bit ? VP8EntropyCost[proba] : VP8EntropyCost[255 - proba];
30}
31
32// Level cost calculations
33extern const uint16_t VP8LevelCodes[MAX_VARIABLE_LEVEL][2];
34void VP8CalculateLevelCosts(VP8Proba* const proba);
35static WEBP_INLINE int VP8LevelCost(const uint16_t* const table, int level) {
36  return VP8LevelFixedCosts[level]
37       + table[(level > MAX_VARIABLE_LEVEL) ? MAX_VARIABLE_LEVEL : level];
38}
39
40// Mode costs
41extern const uint16_t VP8FixedCostsUV[4];
42extern const uint16_t VP8FixedCostsI16[4];
43extern const uint16_t VP8FixedCostsI4[NUM_BMODES][NUM_BMODES][NUM_BMODES];
44
45//------------------------------------------------------------------------------
46
47#if defined(__cplusplus) || defined(c_plusplus)
48}    // extern "C"
49#endif
50
51#endif  /* WEBP_ENC_COST_H_ */
52