michael@0: /*
michael@0:  *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
michael@0:  *
michael@0:  *  Use of this source code is governed by a BSD-style license
michael@0:  *  that can be found in the LICENSE file in the root of the source
michael@0:  *  tree. An additional intellectual property rights grant can be found
michael@0:  *  in the file PATENTS.  All contributing project authors may
michael@0:  *  be found in the AUTHORS file in the root of the source tree.
michael@0:  */
michael@0: 
michael@0: 
michael@0: #ifndef __INC_ENTROPY_H
michael@0: #define __INC_ENTROPY_H
michael@0: 
michael@0: #include "treecoder.h"
michael@0: #include "blockd.h"
michael@0: 
michael@0: /* Coefficient token alphabet */
michael@0: 
michael@0: #define ZERO_TOKEN              0       /* 0         Extra Bits 0+0 */
michael@0: #define ONE_TOKEN               1       /* 1         Extra Bits 0+1 */
michael@0: #define TWO_TOKEN               2       /* 2         Extra Bits 0+1 */
michael@0: #define THREE_TOKEN             3       /* 3         Extra Bits 0+1 */
michael@0: #define FOUR_TOKEN              4       /* 4         Extra Bits 0+1 */
michael@0: #define DCT_VAL_CATEGORY1       5       /* 5-6       Extra Bits 1+1 */
michael@0: #define DCT_VAL_CATEGORY2       6       /* 7-10      Extra Bits 2+1 */
michael@0: #define DCT_VAL_CATEGORY3       7       /* 11-18     Extra Bits 3+1 */
michael@0: #define DCT_VAL_CATEGORY4       8       /* 19-34     Extra Bits 4+1 */
michael@0: #define DCT_VAL_CATEGORY5       9       /* 35-66     Extra Bits 5+1 */
michael@0: #define DCT_VAL_CATEGORY6       10      /* 67+       Extra Bits 11+1 */
michael@0: #define DCT_EOB_TOKEN           11      /* EOB       Extra Bits 0+0 */
michael@0: 
michael@0: #define MAX_ENTROPY_TOKENS 12
michael@0: #define ENTROPY_NODES 11
michael@0: 
michael@0: extern const vp8_tree_index vp8_coef_tree[];
michael@0: 
michael@0: extern const struct vp8_token_struct vp8_coef_encodings[MAX_ENTROPY_TOKENS];
michael@0: 
michael@0: typedef struct
michael@0: {
michael@0:     vp8_tree_p tree;
michael@0:     const vp8_prob *prob;
michael@0:     int Len;
michael@0:     int base_val;
michael@0: } vp8_extra_bit_struct;
michael@0: 
michael@0: extern const vp8_extra_bit_struct vp8_extra_bits[12];    /* indexed by token value */
michael@0: 
michael@0: #define PROB_UPDATE_BASELINE_COST   7
michael@0: 
michael@0: #define MAX_PROB                255
michael@0: #define DCT_MAX_VALUE           2048
michael@0: 
michael@0: 
michael@0: /* Coefficients are predicted via a 3-dimensional probability table. */
michael@0: 
michael@0: /* Outside dimension.  0 = Y no DC, 1 = Y2, 2 = UV, 3 = Y with DC */
michael@0: 
michael@0: #define BLOCK_TYPES 4
michael@0: 
michael@0: /* Middle dimension is a coarsening of the coefficient's
michael@0:    position within the 4x4 DCT. */
michael@0: 
michael@0: #define COEF_BANDS 8
michael@0: extern DECLARE_ALIGNED(16, const unsigned char, vp8_coef_bands[16]);
michael@0: 
michael@0: /* Inside dimension is 3-valued measure of nearby complexity, that is,
michael@0:    the extent to which nearby coefficients are nonzero.  For the first
michael@0:    coefficient (DC, unless block type is 0), we look at the (already encoded)
michael@0:    blocks above and to the left of the current block.  The context index is
michael@0:    then the number (0,1,or 2) of these blocks having nonzero coefficients.
michael@0:    After decoding a coefficient, the measure is roughly the size of the
michael@0:    most recently decoded coefficient (0 for 0, 1 for 1, 2 for >1).
michael@0:    Note that the intuitive meaning of this measure changes as coefficients
michael@0:    are decoded, e.g., prior to the first token, a zero means that my neighbors
michael@0:    are empty while, after the first token, because of the use of end-of-block,
michael@0:    a zero means we just decoded a zero and hence guarantees that a non-zero
michael@0:    coefficient will appear later in this block.  However, this shift
michael@0:    in meaning is perfectly OK because our context depends also on the
michael@0:    coefficient band (and since zigzag positions 0, 1, and 2 are in
michael@0:    distinct bands). */
michael@0: 
michael@0: /*# define DC_TOKEN_CONTEXTS        3*/ /* 00, 0!0, !0!0 */
michael@0: #   define PREV_COEF_CONTEXTS       3
michael@0: 
michael@0: extern DECLARE_ALIGNED(16, const unsigned char, vp8_prev_token_class[MAX_ENTROPY_TOKENS]);
michael@0: 
michael@0: extern const vp8_prob vp8_coef_update_probs [BLOCK_TYPES] [COEF_BANDS] [PREV_COEF_CONTEXTS] [ENTROPY_NODES];
michael@0: 
michael@0: 
michael@0: struct VP8Common;
michael@0: void vp8_default_coef_probs(struct VP8Common *);
michael@0: 
michael@0: extern DECLARE_ALIGNED(16, const int, vp8_default_zig_zag1d[16]);
michael@0: extern DECLARE_ALIGNED(16, const short, vp8_default_inv_zig_zag[16]);
michael@0: extern DECLARE_ALIGNED(16, const short, vp8_default_zig_zag_mask[16]);
michael@0: extern const int vp8_mb_feature_data_bits[MB_LVL_MAX];
michael@0: 
michael@0: void vp8_coef_tree_initialize(void);
michael@0: #endif