media/libvpx/vp8/common/entropy.h@ac0c01689b40 (annotated)
media/libvpx/vp8/common/entropy.h
Thu, 15 Jan 2015 15:59:08 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Thu, 15 Jan 2015 15:59:08 +0100
- branch
- TOR_BUG_9701
- changeset 10
- ac0c01689b40
- permissions
- -rw-r--r--
Implement a real Private Browsing Mode condition by changing the API/ABI;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.
| michael@0 | 1 | /* |
| michael@0 | 2 | * Copyright (c) 2010 The WebM project authors. All Rights Reserved. |
| michael@0 | 3 | * |
| michael@0 | 4 | * Use of this source code is governed by a BSD-style license |
| michael@0 | 5 | * that can be found in the LICENSE file in the root of the source |
| michael@0 | 6 | * tree. An additional intellectual property rights grant can be found |
| michael@0 | 7 | * in the file PATENTS. All contributing project authors may |
| michael@0 | 8 | * be found in the AUTHORS file in the root of the source tree. |
| michael@0 | 9 | */ |
| michael@0 | 10 | |
| michael@0 | 11 | |
| michael@0 | 12 | #ifndef __INC_ENTROPY_H |
| michael@0 | 13 | #define __INC_ENTROPY_H |
| michael@0 | 14 | |
| michael@0 | 15 | #include "treecoder.h" |
| michael@0 | 16 | #include "blockd.h" |
| michael@0 | 17 | |
| michael@0 | 18 | /* Coefficient token alphabet */ |
| michael@0 | 19 | |
| michael@0 | 20 | #define ZERO_TOKEN 0 /* 0 Extra Bits 0+0 */ |
| michael@0 | 21 | #define ONE_TOKEN 1 /* 1 Extra Bits 0+1 */ |
| michael@0 | 22 | #define TWO_TOKEN 2 /* 2 Extra Bits 0+1 */ |
| michael@0 | 23 | #define THREE_TOKEN 3 /* 3 Extra Bits 0+1 */ |
| michael@0 | 24 | #define FOUR_TOKEN 4 /* 4 Extra Bits 0+1 */ |
| michael@0 | 25 | #define DCT_VAL_CATEGORY1 5 /* 5-6 Extra Bits 1+1 */ |
| michael@0 | 26 | #define DCT_VAL_CATEGORY2 6 /* 7-10 Extra Bits 2+1 */ |
| michael@0 | 27 | #define DCT_VAL_CATEGORY3 7 /* 11-18 Extra Bits 3+1 */ |
| michael@0 | 28 | #define DCT_VAL_CATEGORY4 8 /* 19-34 Extra Bits 4+1 */ |
| michael@0 | 29 | #define DCT_VAL_CATEGORY5 9 /* 35-66 Extra Bits 5+1 */ |
| michael@0 | 30 | #define DCT_VAL_CATEGORY6 10 /* 67+ Extra Bits 11+1 */ |
| michael@0 | 31 | #define DCT_EOB_TOKEN 11 /* EOB Extra Bits 0+0 */ |
| michael@0 | 32 | |
| michael@0 | 33 | #define MAX_ENTROPY_TOKENS 12 |
| michael@0 | 34 | #define ENTROPY_NODES 11 |
| michael@0 | 35 | |
| michael@0 | 36 | extern const vp8_tree_index vp8_coef_tree[]; |
| michael@0 | 37 | |
| michael@0 | 38 | extern const struct vp8_token_struct vp8_coef_encodings[MAX_ENTROPY_TOKENS]; |
| michael@0 | 39 | |
| michael@0 | 40 | typedef struct |
| michael@0 | 41 | { |
| michael@0 | 42 | vp8_tree_p tree; |
| michael@0 | 43 | const vp8_prob *prob; |
| michael@0 | 44 | int Len; |
| michael@0 | 45 | int base_val; |
| michael@0 | 46 | } vp8_extra_bit_struct; |
| michael@0 | 47 | |
| michael@0 | 48 | extern const vp8_extra_bit_struct vp8_extra_bits[12]; /* indexed by token value */ |
| michael@0 | 49 | |
| michael@0 | 50 | #define PROB_UPDATE_BASELINE_COST 7 |
| michael@0 | 51 | |
| michael@0 | 52 | #define MAX_PROB 255 |
| michael@0 | 53 | #define DCT_MAX_VALUE 2048 |
| michael@0 | 54 | |
| michael@0 | 55 | |
| michael@0 | 56 | /* Coefficients are predicted via a 3-dimensional probability table. */ |
| michael@0 | 57 | |
| michael@0 | 58 | /* Outside dimension. 0 = Y no DC, 1 = Y2, 2 = UV, 3 = Y with DC */ |
| michael@0 | 59 | |
| michael@0 | 60 | #define BLOCK_TYPES 4 |
| michael@0 | 61 | |
| michael@0 | 62 | /* Middle dimension is a coarsening of the coefficient's |
| michael@0 | 63 | position within the 4x4 DCT. */ |
| michael@0 | 64 | |
| michael@0 | 65 | #define COEF_BANDS 8 |
| michael@0 | 66 | extern DECLARE_ALIGNED(16, const unsigned char, vp8_coef_bands[16]); |
| michael@0 | 67 | |
| michael@0 | 68 | /* Inside dimension is 3-valued measure of nearby complexity, that is, |
| michael@0 | 69 | the extent to which nearby coefficients are nonzero. For the first |
| michael@0 | 70 | coefficient (DC, unless block type is 0), we look at the (already encoded) |
| michael@0 | 71 | blocks above and to the left of the current block. The context index is |
| michael@0 | 72 | then the number (0,1,or 2) of these blocks having nonzero coefficients. |
| michael@0 | 73 | After decoding a coefficient, the measure is roughly the size of the |
| michael@0 | 74 | most recently decoded coefficient (0 for 0, 1 for 1, 2 for >1). |
| michael@0 | 75 | Note that the intuitive meaning of this measure changes as coefficients |
| michael@0 | 76 | are decoded, e.g., prior to the first token, a zero means that my neighbors |
| michael@0 | 77 | are empty while, after the first token, because of the use of end-of-block, |
| michael@0 | 78 | a zero means we just decoded a zero and hence guarantees that a non-zero |
| michael@0 | 79 | coefficient will appear later in this block. However, this shift |
| michael@0 | 80 | in meaning is perfectly OK because our context depends also on the |
| michael@0 | 81 | coefficient band (and since zigzag positions 0, 1, and 2 are in |
| michael@0 | 82 | distinct bands). */ |
| michael@0 | 83 | |
| michael@0 | 84 | /*# define DC_TOKEN_CONTEXTS 3*/ /* 00, 0!0, !0!0 */ |
| michael@0 | 85 | # define PREV_COEF_CONTEXTS 3 |
| michael@0 | 86 | |
| michael@0 | 87 | extern DECLARE_ALIGNED(16, const unsigned char, vp8_prev_token_class[MAX_ENTROPY_TOKENS]); |
| michael@0 | 88 | |
| michael@0 | 89 | extern const vp8_prob vp8_coef_update_probs [BLOCK_TYPES] [COEF_BANDS] [PREV_COEF_CONTEXTS] [ENTROPY_NODES]; |
| michael@0 | 90 | |
| michael@0 | 91 | |
| michael@0 | 92 | struct VP8Common; |
| michael@0 | 93 | void vp8_default_coef_probs(struct VP8Common *); |
| michael@0 | 94 | |
| michael@0 | 95 | extern DECLARE_ALIGNED(16, const int, vp8_default_zig_zag1d[16]); |
| michael@0 | 96 | extern DECLARE_ALIGNED(16, const short, vp8_default_inv_zig_zag[16]); |
| michael@0 | 97 | extern DECLARE_ALIGNED(16, const short, vp8_default_zig_zag_mask[16]); |
| michael@0 | 98 | extern const int vp8_mb_feature_data_bits[MB_LVL_MAX]; |
| michael@0 | 99 | |
| michael@0 | 100 | void vp8_coef_tree_initialize(void); |
| michael@0 | 101 | #endif |
