| /* |
| * 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 |