1 /* 2 * Copyright (c) 2010 The WebM project authors. All Rights Reserved. 3 * 4 * Use of this source code is governed by a BSD-style license 5 * that can be found in the LICENSE file in the root of the source 6 * tree. An additional intellectual property rights grant can be found 7 * in the file PATENTS. All contributing project authors may 8 * be found in the AUTHORS file in the root of the source tree. 9 */ 10 11 12 #ifndef VP9_ENCODER_VP9_RATECTRL_H_ 13 #define VP9_ENCODER_VP9_RATECTRL_H_ 14 15 #include "vpx/vpx_integer.h" 16 17 #include "vp9/common/vp9_blockd.h" 18 19 #ifdef __cplusplus 20 extern "C" { 21 #endif 22 23 #define FRAME_OVERHEAD_BITS 200 24 25 typedef struct { 26 // Rate targetting variables 27 int this_frame_target; 28 int projected_frame_size; 29 int sb64_target_rate; 30 int last_q[3]; // Separate values for Intra/Inter/ARF-GF 31 int last_boosted_qindex; // Last boosted GF/KF/ARF q 32 33 int gfu_boost; 34 int last_boost; 35 int kf_boost; 36 37 double rate_correction_factor; 38 double key_frame_rate_correction_factor; 39 double gf_rate_correction_factor; 40 41 int frames_since_golden; 42 int frames_till_gf_update_due; 43 int max_gf_interval; 44 int static_scene_max_gf_interval; 45 int baseline_gf_interval; 46 int frames_to_key; 47 int frames_since_key; 48 int this_key_frame_forced; 49 int next_key_frame_forced; 50 int source_alt_ref_pending; 51 int source_alt_ref_active; 52 int is_src_frame_alt_ref; 53 54 int av_per_frame_bandwidth; // Average frame size target for clip 55 int min_frame_bandwidth; // Minimum allocation used for any frame 56 int max_frame_bandwidth; // Maximum burst rate allowed for a frame. 57 58 int ni_av_qi; 59 int ni_tot_qi; 60 int ni_frames; 61 int avg_frame_qindex[3]; // 0 - KEY, 1 - INTER, 2 - ARF/GF 62 double tot_q; 63 double avg_q; 64 65 int64_t buffer_level; 66 int64_t bits_off_target; 67 68 int decimation_factor; 69 int decimation_count; 70 71 int rolling_target_bits; 72 int rolling_actual_bits; 73 74 int long_rolling_target_bits; 75 int long_rolling_actual_bits; 76 77 int64_t total_actual_bits; 78 int64_t total_target_bits; 79 int64_t total_target_vs_actual; 80 81 int worst_quality; 82 int best_quality; 83 // int active_best_quality; 84 } RATE_CONTROL; 85 86 struct VP9_COMP; 87 88 void vp9_save_coding_context(struct VP9_COMP *cpi); 89 void vp9_restore_coding_context(struct VP9_COMP *cpi); 90 91 double vp9_convert_qindex_to_q(int qindex); 92 93 void vp9_rc_init_minq_luts(); 94 95 // Generally at the high level, the following flow is expected 96 // to be enforced for rate control: 97 // First call per frame, one of: 98 // vp9_rc_get_one_pass_vbr_params() 99 // vp9_rc_get_one_pass_cbr_params() 100 // vp9_rc_get_svc_params() 101 // vp9_rc_get_first_pass_params() 102 // vp9_rc_get_second_pass_params() 103 // depending on the usage to set the rate control encode parameters desired. 104 // 105 // Then, call encode_frame_to_data_rate() to perform the 106 // actual encode. This function will in turn call encode_frame() 107 // one or more times, followed by one of: 108 // vp9_rc_postencode_update() 109 // vp9_rc_postencode_update_drop_frame() 110 // 111 // The majority of rate control parameters are only expected 112 // to be set in the vp9_rc_get_..._params() functions and 113 // updated during the vp9_rc_postencode_update...() functions. 114 // The only exceptions are vp9_rc_drop_frame() and 115 // vp9_rc_update_rate_correction_factors() functions. 116 117 // Functions to set parameters for encoding before the actual 118 // encode_frame_to_data_rate() function. 119 void vp9_rc_get_one_pass_vbr_params(struct VP9_COMP *cpi); 120 void vp9_rc_get_one_pass_cbr_params(struct VP9_COMP *cpi); 121 void vp9_rc_get_svc_params(struct VP9_COMP *cpi); 122 123 // Post encode update of the rate control parameters based 124 // on bytes used 125 void vp9_rc_postencode_update(struct VP9_COMP *cpi, 126 uint64_t bytes_used); 127 // Post encode update of the rate control parameters for dropped frames 128 void vp9_rc_postencode_update_drop_frame(struct VP9_COMP *cpi); 129 130 // Updates rate correction factors 131 // Changes only the rate correction factors in the rate control structure. 132 void vp9_rc_update_rate_correction_factors(struct VP9_COMP *cpi, int damp_var); 133 134 // Decide if we should drop this frame: For 1-pass CBR. 135 // Changes only the decimation count in the rate control structure 136 int vp9_rc_drop_frame(struct VP9_COMP *cpi); 137 138 // Computes frame size bounds. 139 void vp9_rc_compute_frame_size_bounds(const struct VP9_COMP *cpi, 140 int this_frame_target, 141 int *frame_under_shoot_limit, 142 int *frame_over_shoot_limit); 143 144 // Picks q and q bounds given the target for bits 145 int vp9_rc_pick_q_and_bounds(const struct VP9_COMP *cpi, 146 int *bottom_index, 147 int *top_index); 148 149 // Estimates q to achieve a target bits per frame 150 int vp9_rc_regulate_q(const struct VP9_COMP *cpi, int target_bits_per_frame, 151 int active_best_quality, int active_worst_quality); 152 153 // Estimates bits per mb for a given qindex and correction factor. 154 int vp9_rc_bits_per_mb(FRAME_TYPE frame_type, int qindex, 155 double correction_factor); 156 157 // Clamping utilities for bitrate targets for iframes and pframes. 158 int vp9_rc_clamp_iframe_target_size(const struct VP9_COMP *const cpi, 159 int target); 160 int vp9_rc_clamp_pframe_target_size(const struct VP9_COMP *const cpi, 161 int target); 162 // Utility to set frame_target into the RATE_CONTROL structure 163 // This function is called only from the vp9_rc_get_..._params() functions. 164 void vp9_rc_set_frame_target(struct VP9_COMP *cpi, int target); 165 166 #ifdef __cplusplus 167 } // extern "C" 168 #endif 169 170 #endif // VP9_ENCODER_VP9_RATECTRL_H_ 171