/* | |

* Copyright (c) 2010 The VP8 project authors. All Rights Reserved. | |

* | |

* Use of this source code is governed by a BSD-style license and patent | |

* grant that can be found in the LICENSE file in the root of the source | |

* tree. All contributing project authors may be found in the AUTHORS | |

* file in the root of the source tree. | |

*/ | |

#ifndef __INC_ENTROPY_H | |

#define __INC_ENTROPY_H | |

#include "treecoder.h" | |

#include "blockd.h" | |

/* Coefficient token alphabet */ | |

#define ZERO_TOKEN 0 //0 Extra Bits 0+0 | |

#define ONE_TOKEN 1 //1 Extra Bits 0+1 | |

#define TWO_TOKEN 2 //2 Extra Bits 0+1 | |

#define THREE_TOKEN 3 //3 Extra Bits 0+1 | |

#define FOUR_TOKEN 4 //4 Extra Bits 0+1 | |

#define DCT_VAL_CATEGORY1 5 //5-6 Extra Bits 1+1 | |

#define DCT_VAL_CATEGORY2 6 //7-10 Extra Bits 2+1 | |

#define DCT_VAL_CATEGORY3 7 //11-26 Extra Bits 4+1 | |

#define DCT_VAL_CATEGORY4 8 //11-26 Extra Bits 5+1 | |

#define DCT_VAL_CATEGORY5 9 //27-58 Extra Bits 5+1 | |

#define DCT_VAL_CATEGORY6 10 //59+ Extra Bits 11+1 | |

#define DCT_EOB_TOKEN 11 //EOB Extra Bits 0+0 | |

#define vp8_coef_tokens 12 | |

#define MAX_ENTROPY_TOKENS vp8_coef_tokens | |

#define ENTROPY_NODES 11 | |

extern const vp8_tree_index vp8_coef_tree[]; | |

extern struct vp8_token_struct vp8_coef_encodings[vp8_coef_tokens]; | |

typedef struct | |

{ | |

vp8_tree_p tree; | |

const vp8_prob *prob; | |

vp8bc_index_t *prob_bc; | |

int Len; | |

int base_val; | |

} vp8_extra_bit_struct; | |

extern vp8_extra_bit_struct vp8_extra_bits[12]; /* indexed by token value */ | |

#define PROB_UPDATE_BASELINE_COST 7 | |

#define MAX_PROB 255 | |

#define DCT_MAX_VALUE 2048 | |

/* Coefficients are predicted via a 3-dimensional probability table. */ | |

/* Outside dimension. 0 = Y no DC, 1 = Y2, 2 = UV, 3 = Y with DC */ | |

#define BLOCK_TYPES 4 | |

/* Middle dimension is a coarsening of the coefficient's | |

position within the 4x4 DCT. */ | |

#define COEF_BANDS 8 | |

extern DECLARE_ALIGNED(16, const unsigned char, vp8_coef_bands[16]); | |

/* Inside dimension is 3-valued measure of nearby complexity, that is, | |

the extent to which nearby coefficients are nonzero. For the first | |

coefficient (DC, unless block type is 0), we look at the (already encoded) | |

blocks above and to the left of the current block. The context index is | |

then the number (0,1,or 2) of these blocks having nonzero coefficients. | |

After decoding a coefficient, the measure is roughly the size of the | |

most recently decoded coefficient (0 for 0, 1 for 1, 2 for >1). | |

Note that the intuitive meaning of this measure changes as coefficients | |

are decoded, e.g., prior to the first token, a zero means that my neighbors | |

are empty while, after the first token, because of the use of end-of-block, | |

a zero means we just decoded a zero and hence guarantees that a non-zero | |

coefficient will appear later in this block. However, this shift | |

in meaning is perfectly OK because our context depends also on the | |

coefficient band (and since zigzag positions 0, 1, and 2 are in | |

distinct bands). */ | |

/*# define DC_TOKEN_CONTEXTS 3 // 00, 0!0, !0!0 */ | |

# define PREV_COEF_CONTEXTS 3 | |

extern DECLARE_ALIGNED(16, const unsigned char, vp8_prev_token_class[vp8_coef_tokens]); | |

extern const vp8_prob vp8_coef_update_probs [BLOCK_TYPES] [COEF_BANDS] [PREV_COEF_CONTEXTS] [vp8_coef_tokens-1]; | |

struct VP8Common; | |

void vp8_default_coef_probs(struct VP8Common *); | |

extern DECLARE_ALIGNED(16, const int, vp8_default_zig_zag1d[16]); | |

extern short vp8_default_zig_zag_mask[16]; | |

extern const int vp8_mb_feature_data_bits[MB_LVL_MAX]; | |

void vp8_coef_tree_initialize(void); | |

#endif |