1233d2500723e5594f3e7c70896ffeeef32b9c950ywan/* 2233d2500723e5594f3e7c70896ffeeef32b9c950ywan * Copyright (c) 2010 The WebM project authors. All Rights Reserved. 3233d2500723e5594f3e7c70896ffeeef32b9c950ywan * 4233d2500723e5594f3e7c70896ffeeef32b9c950ywan * Use of this source code is governed by a BSD-style license 5233d2500723e5594f3e7c70896ffeeef32b9c950ywan * that can be found in the LICENSE file in the root of the source 6233d2500723e5594f3e7c70896ffeeef32b9c950ywan * tree. An additional intellectual property rights grant can be found 7233d2500723e5594f3e7c70896ffeeef32b9c950ywan * in the file PATENTS. All contributing project authors may 8233d2500723e5594f3e7c70896ffeeef32b9c950ywan * be found in the AUTHORS file in the root of the source tree. 9233d2500723e5594f3e7c70896ffeeef32b9c950ywan */ 10233d2500723e5594f3e7c70896ffeeef32b9c950ywan 11233d2500723e5594f3e7c70896ffeeef32b9c950ywan 12233d2500723e5594f3e7c70896ffeeef32b9c950ywan#ifndef VP8_ENCODER_TREEWRITER_H_ 13233d2500723e5594f3e7c70896ffeeef32b9c950ywan#define VP8_ENCODER_TREEWRITER_H_ 14233d2500723e5594f3e7c70896ffeeef32b9c950ywan 15233d2500723e5594f3e7c70896ffeeef32b9c950ywan/* Trees map alphabets into huffman-like codes suitable for an arithmetic 16233d2500723e5594f3e7c70896ffeeef32b9c950ywan bit coder. Timothy S Murphy 11 October 2004 */ 17233d2500723e5594f3e7c70896ffeeef32b9c950ywan 18233d2500723e5594f3e7c70896ffeeef32b9c950ywan#include "vp8/common/treecoder.h" 19233d2500723e5594f3e7c70896ffeeef32b9c950ywan 20233d2500723e5594f3e7c70896ffeeef32b9c950ywan#include "boolhuff.h" /* for now */ 21233d2500723e5594f3e7c70896ffeeef32b9c950ywan 22233d2500723e5594f3e7c70896ffeeef32b9c950ywan#ifdef __cplusplus 23233d2500723e5594f3e7c70896ffeeef32b9c950ywanextern "C" { 24233d2500723e5594f3e7c70896ffeeef32b9c950ywan#endif 25233d2500723e5594f3e7c70896ffeeef32b9c950ywan 26233d2500723e5594f3e7c70896ffeeef32b9c950ywantypedef BOOL_CODER vp8_writer; 27233d2500723e5594f3e7c70896ffeeef32b9c950ywan 28233d2500723e5594f3e7c70896ffeeef32b9c950ywan#define vp8_write vp8_encode_bool 29233d2500723e5594f3e7c70896ffeeef32b9c950ywan#define vp8_write_literal vp8_encode_value 30233d2500723e5594f3e7c70896ffeeef32b9c950ywan#define vp8_write_bit( W, V) vp8_write( W, V, vp8_prob_half) 31233d2500723e5594f3e7c70896ffeeef32b9c950ywan 32233d2500723e5594f3e7c70896ffeeef32b9c950ywan#define vp8bc_write vp8bc_write_bool 33233d2500723e5594f3e7c70896ffeeef32b9c950ywan#define vp8bc_write_literal vp8bc_write_bits 34233d2500723e5594f3e7c70896ffeeef32b9c950ywan#define vp8bc_write_bit( W, V) vp8bc_write_bits( W, V, 1) 35233d2500723e5594f3e7c70896ffeeef32b9c950ywan 36233d2500723e5594f3e7c70896ffeeef32b9c950ywan 37233d2500723e5594f3e7c70896ffeeef32b9c950ywan/* Approximate length of an encoded bool in 256ths of a bit at given prob */ 38233d2500723e5594f3e7c70896ffeeef32b9c950ywan 39233d2500723e5594f3e7c70896ffeeef32b9c950ywan#define vp8_cost_zero( x) ( vp8_prob_cost[x]) 40233d2500723e5594f3e7c70896ffeeef32b9c950ywan#define vp8_cost_one( x) vp8_cost_zero( vp8_complement(x)) 41233d2500723e5594f3e7c70896ffeeef32b9c950ywan 42233d2500723e5594f3e7c70896ffeeef32b9c950ywan#define vp8_cost_bit( x, b) vp8_cost_zero( (b)? vp8_complement(x) : (x) ) 43233d2500723e5594f3e7c70896ffeeef32b9c950ywan 44233d2500723e5594f3e7c70896ffeeef32b9c950ywan/* VP8BC version is scaled by 2^20 rather than 2^8; see bool_coder.h */ 45233d2500723e5594f3e7c70896ffeeef32b9c950ywan 46233d2500723e5594f3e7c70896ffeeef32b9c950ywan 47233d2500723e5594f3e7c70896ffeeef32b9c950ywan/* Both of these return bits, not scaled bits. */ 48233d2500723e5594f3e7c70896ffeeef32b9c950ywan 49233d2500723e5594f3e7c70896ffeeef32b9c950ywanstatic unsigned int vp8_cost_branch(const unsigned int ct[2], vp8_prob p) 50233d2500723e5594f3e7c70896ffeeef32b9c950ywan{ 51233d2500723e5594f3e7c70896ffeeef32b9c950ywan /* Imitate existing calculation */ 52233d2500723e5594f3e7c70896ffeeef32b9c950ywan 53233d2500723e5594f3e7c70896ffeeef32b9c950ywan return ((ct[0] * vp8_cost_zero(p)) 54233d2500723e5594f3e7c70896ffeeef32b9c950ywan + (ct[1] * vp8_cost_one(p))) >> 8; 55233d2500723e5594f3e7c70896ffeeef32b9c950ywan} 56233d2500723e5594f3e7c70896ffeeef32b9c950ywan 57233d2500723e5594f3e7c70896ffeeef32b9c950ywan/* Small functions to write explicit values and tokens, as well as 58233d2500723e5594f3e7c70896ffeeef32b9c950ywan estimate their lengths. */ 59233d2500723e5594f3e7c70896ffeeef32b9c950ywan 60233d2500723e5594f3e7c70896ffeeef32b9c950ywanstatic void vp8_treed_write 61233d2500723e5594f3e7c70896ffeeef32b9c950ywan( 62233d2500723e5594f3e7c70896ffeeef32b9c950ywan vp8_writer *const w, 63233d2500723e5594f3e7c70896ffeeef32b9c950ywan vp8_tree t, 64233d2500723e5594f3e7c70896ffeeef32b9c950ywan const vp8_prob *const p, 65233d2500723e5594f3e7c70896ffeeef32b9c950ywan int v, 66233d2500723e5594f3e7c70896ffeeef32b9c950ywan int n /* number of bits in v, assumed nonzero */ 67233d2500723e5594f3e7c70896ffeeef32b9c950ywan) 68233d2500723e5594f3e7c70896ffeeef32b9c950ywan{ 69233d2500723e5594f3e7c70896ffeeef32b9c950ywan vp8_tree_index i = 0; 70233d2500723e5594f3e7c70896ffeeef32b9c950ywan 71233d2500723e5594f3e7c70896ffeeef32b9c950ywan do 72233d2500723e5594f3e7c70896ffeeef32b9c950ywan { 73233d2500723e5594f3e7c70896ffeeef32b9c950ywan const int b = (v >> --n) & 1; 74233d2500723e5594f3e7c70896ffeeef32b9c950ywan vp8_write(w, b, p[i>>1]); 75233d2500723e5594f3e7c70896ffeeef32b9c950ywan i = t[i+b]; 76233d2500723e5594f3e7c70896ffeeef32b9c950ywan } 77233d2500723e5594f3e7c70896ffeeef32b9c950ywan while (n); 78233d2500723e5594f3e7c70896ffeeef32b9c950ywan} 79233d2500723e5594f3e7c70896ffeeef32b9c950ywanstatic void vp8_write_token 80233d2500723e5594f3e7c70896ffeeef32b9c950ywan( 81233d2500723e5594f3e7c70896ffeeef32b9c950ywan vp8_writer *const w, 82233d2500723e5594f3e7c70896ffeeef32b9c950ywan vp8_tree t, 83233d2500723e5594f3e7c70896ffeeef32b9c950ywan const vp8_prob *const p, 84233d2500723e5594f3e7c70896ffeeef32b9c950ywan vp8_token *const x 85233d2500723e5594f3e7c70896ffeeef32b9c950ywan) 86233d2500723e5594f3e7c70896ffeeef32b9c950ywan{ 87233d2500723e5594f3e7c70896ffeeef32b9c950ywan vp8_treed_write(w, t, p, x->value, x->Len); 88233d2500723e5594f3e7c70896ffeeef32b9c950ywan} 89233d2500723e5594f3e7c70896ffeeef32b9c950ywan 90233d2500723e5594f3e7c70896ffeeef32b9c950ywanstatic int vp8_treed_cost( 91233d2500723e5594f3e7c70896ffeeef32b9c950ywan vp8_tree t, 92233d2500723e5594f3e7c70896ffeeef32b9c950ywan const vp8_prob *const p, 93233d2500723e5594f3e7c70896ffeeef32b9c950ywan int v, 94233d2500723e5594f3e7c70896ffeeef32b9c950ywan int n /* number of bits in v, assumed nonzero */ 95233d2500723e5594f3e7c70896ffeeef32b9c950ywan) 96233d2500723e5594f3e7c70896ffeeef32b9c950ywan{ 97233d2500723e5594f3e7c70896ffeeef32b9c950ywan int c = 0; 98233d2500723e5594f3e7c70896ffeeef32b9c950ywan vp8_tree_index i = 0; 99233d2500723e5594f3e7c70896ffeeef32b9c950ywan 100233d2500723e5594f3e7c70896ffeeef32b9c950ywan do 101233d2500723e5594f3e7c70896ffeeef32b9c950ywan { 102233d2500723e5594f3e7c70896ffeeef32b9c950ywan const int b = (v >> --n) & 1; 103233d2500723e5594f3e7c70896ffeeef32b9c950ywan c += vp8_cost_bit(p[i>>1], b); 104233d2500723e5594f3e7c70896ffeeef32b9c950ywan i = t[i+b]; 105233d2500723e5594f3e7c70896ffeeef32b9c950ywan } 106233d2500723e5594f3e7c70896ffeeef32b9c950ywan while (n); 107233d2500723e5594f3e7c70896ffeeef32b9c950ywan 108233d2500723e5594f3e7c70896ffeeef32b9c950ywan return c; 109233d2500723e5594f3e7c70896ffeeef32b9c950ywan} 110233d2500723e5594f3e7c70896ffeeef32b9c950ywanstatic int vp8_cost_token 111233d2500723e5594f3e7c70896ffeeef32b9c950ywan( 112233d2500723e5594f3e7c70896ffeeef32b9c950ywan vp8_tree t, 113233d2500723e5594f3e7c70896ffeeef32b9c950ywan const vp8_prob *const p, 114233d2500723e5594f3e7c70896ffeeef32b9c950ywan vp8_token *const x 115233d2500723e5594f3e7c70896ffeeef32b9c950ywan) 116233d2500723e5594f3e7c70896ffeeef32b9c950ywan{ 117233d2500723e5594f3e7c70896ffeeef32b9c950ywan return vp8_treed_cost(t, p, x->value, x->Len); 118233d2500723e5594f3e7c70896ffeeef32b9c950ywan} 119233d2500723e5594f3e7c70896ffeeef32b9c950ywan 120233d2500723e5594f3e7c70896ffeeef32b9c950ywan/* Fill array of costs for all possible token values. */ 121233d2500723e5594f3e7c70896ffeeef32b9c950ywan 122233d2500723e5594f3e7c70896ffeeef32b9c950ywanvoid vp8_cost_tokens( 123233d2500723e5594f3e7c70896ffeeef32b9c950ywan int *Costs, const vp8_prob *, vp8_tree 124233d2500723e5594f3e7c70896ffeeef32b9c950ywan); 125233d2500723e5594f3e7c70896ffeeef32b9c950ywan 126233d2500723e5594f3e7c70896ffeeef32b9c950ywanvoid vp8_cost_tokens2( 127233d2500723e5594f3e7c70896ffeeef32b9c950ywan int *Costs, const vp8_prob *, vp8_tree, int 128233d2500723e5594f3e7c70896ffeeef32b9c950ywan); 129233d2500723e5594f3e7c70896ffeeef32b9c950ywan 130233d2500723e5594f3e7c70896ffeeef32b9c950ywan#ifdef __cplusplus 131233d2500723e5594f3e7c70896ffeeef32b9c950ywan} // extern "C" 132233d2500723e5594f3e7c70896ffeeef32b9c950ywan#endif 133233d2500723e5594f3e7c70896ffeeef32b9c950ywan 134233d2500723e5594f3e7c70896ffeeef32b9c950ywan#endif // VP8_ENCODER_TREEWRITER_H_ 135