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_codec.h" 16 #include "vpx/vpx_integer.h" 17 18 #include "vp9/common/vp9_blockd.h" 19 20 #ifdef __cplusplus 21 extern "C" { 22 #endif 23 24 // Bits Per MB at different Q (Multiplied by 512) 25 #define BPER_MB_NORMBITS 9 26 27 #define MIN_GF_INTERVAL 4 28 #define MAX_GF_INTERVAL 16 29 #define ONEHALFONLY_RESIZE 0 30 31 typedef enum { 32 INTER_NORMAL = 0, 33 INTER_HIGH = 1, 34 GF_ARF_LOW = 2, 35 GF_ARF_STD = 3, 36 KF_STD = 4, 37 RATE_FACTOR_LEVELS = 5 38 } RATE_FACTOR_LEVEL; 39 40 // Internal frame scaling level. 41 typedef enum { 42 UNSCALED = 0, // Frame is unscaled. 43 SCALE_STEP1 = 1, // First-level down-scaling. 44 FRAME_SCALE_STEPS 45 } FRAME_SCALE_LEVEL; 46 47 typedef enum { 48 NO_RESIZE = 0, 49 DOWN_THREEFOUR = 1, // From orig to 3/4. 50 DOWN_ONEHALF = 2, // From orig or 3/4 to 1/2. 51 UP_THREEFOUR = -1, // From 1/2 to 3/4. 52 UP_ORIG = -2, // From 1/2 or 3/4 to orig. 53 } RESIZE_ACTION; 54 55 typedef enum { 56 ORIG = 0, 57 THREE_QUARTER = 1, 58 ONE_HALF = 2 59 } RESIZE_STATE; 60 61 // Frame dimensions multiplier wrt the native frame size, in 1/16ths, 62 // specified for the scale-up case. 63 // e.g. 24 => 16/24 = 2/3 of native size. The restriction to 1/16th is 64 // intended to match the capabilities of the normative scaling filters, 65 // giving precedence to the up-scaling accuracy. 66 static const int frame_scale_factor[FRAME_SCALE_STEPS] = {16, 24}; 67 68 // Multiplier of the target rate to be used as threshold for triggering scaling. 69 static const double rate_thresh_mult[FRAME_SCALE_STEPS] = {1.0, 2.0}; 70 71 // Scale dependent Rate Correction Factor multipliers. Compensates for the 72 // greater number of bits per pixel generated in down-scaled frames. 73 static const double rcf_mult[FRAME_SCALE_STEPS] = {1.0, 2.0}; 74 75 typedef struct { 76 // Rate targetting variables 77 int base_frame_target; // A baseline frame target before adjustment 78 // for previous under or over shoot. 79 int this_frame_target; // Actual frame target after rc adjustment. 80 int projected_frame_size; 81 int sb64_target_rate; 82 int last_q[FRAME_TYPES]; // Separate values for Intra/Inter 83 int last_boosted_qindex; // Last boosted GF/KF/ARF q 84 int last_kf_qindex; // Q index of the last key frame coded. 85 86 int gfu_boost; 87 int last_boost; 88 int kf_boost; 89 90 double rate_correction_factors[RATE_FACTOR_LEVELS]; 91 92 int frames_since_golden; 93 int frames_till_gf_update_due; 94 int min_gf_interval; 95 int max_gf_interval; 96 int static_scene_max_gf_interval; 97 int baseline_gf_interval; 98 int constrained_gf_group; 99 int frames_to_key; 100 int frames_since_key; 101 int this_key_frame_forced; 102 int next_key_frame_forced; 103 int source_alt_ref_pending; 104 int source_alt_ref_active; 105 int is_src_frame_alt_ref; 106 107 int avg_frame_bandwidth; // Average frame size target for clip 108 int min_frame_bandwidth; // Minimum allocation used for any frame 109 int max_frame_bandwidth; // Maximum burst rate allowed for a frame. 110 111 int ni_av_qi; 112 int ni_tot_qi; 113 int ni_frames; 114 int avg_frame_qindex[FRAME_TYPES]; 115 double tot_q; 116 double avg_q; 117 118 int64_t buffer_level; 119 int64_t bits_off_target; 120 int64_t vbr_bits_off_target; 121 int64_t vbr_bits_off_target_fast; 122 123 int decimation_factor; 124 int decimation_count; 125 126 int rolling_target_bits; 127 int rolling_actual_bits; 128 129 int long_rolling_target_bits; 130 int long_rolling_actual_bits; 131 132 int rate_error_estimate; 133 134 int64_t total_actual_bits; 135 int64_t total_target_bits; 136 int64_t total_target_vs_actual; 137 138 int worst_quality; 139 int best_quality; 140 141 int64_t starting_buffer_level; 142 int64_t optimal_buffer_level; 143 int64_t maximum_buffer_size; 144 145 // rate control history for last frame(1) and the frame before(2). 146 // -1: undershot 147 // 1: overshoot 148 // 0: not initialized. 149 int rc_1_frame; 150 int rc_2_frame; 151 int q_1_frame; 152 int q_2_frame; 153 154 // Auto frame-scaling variables. 155 FRAME_SCALE_LEVEL frame_size_selector; 156 FRAME_SCALE_LEVEL next_frame_size_selector; 157 int frame_width[FRAME_SCALE_STEPS]; 158 int frame_height[FRAME_SCALE_STEPS]; 159 int rf_level_maxq[RATE_FACTOR_LEVELS]; 160 161 uint64_t avg_source_sad; 162 int high_source_sad; 163 } RATE_CONTROL; 164 165 struct VP9_COMP; 166 struct VP9EncoderConfig; 167 168 void vp9_rc_init(const struct VP9EncoderConfig *oxcf, int pass, 169 RATE_CONTROL *rc); 170 171 int vp9_estimate_bits_at_q(FRAME_TYPE frame_kind, int q, int mbs, 172 double correction_factor, 173 vpx_bit_depth_t bit_depth); 174 175 double vp9_convert_qindex_to_q(int qindex, vpx_bit_depth_t bit_depth); 176 177 void vp9_rc_init_minq_luts(void); 178 179 int vp9_rc_get_default_min_gf_interval(int width, int height, double framerate); 180 // Note vp9_rc_get_default_max_gf_interval() requires the min_gf_interval to 181 // be passed in to ensure that the max_gf_interval returned is at least as bis 182 // as that. 183 int vp9_rc_get_default_max_gf_interval(double framerate, int min_frame_rate); 184 185 // Generally at the high level, the following flow is expected 186 // to be enforced for rate control: 187 // First call per frame, one of: 188 // vp9_rc_get_one_pass_vbr_params() 189 // vp9_rc_get_one_pass_cbr_params() 190 // vp9_rc_get_svc_params() 191 // vp9_rc_get_first_pass_params() 192 // vp9_rc_get_second_pass_params() 193 // depending on the usage to set the rate control encode parameters desired. 194 // 195 // Then, call encode_frame_to_data_rate() to perform the 196 // actual encode. This function will in turn call encode_frame() 197 // one or more times, followed by one of: 198 // vp9_rc_postencode_update() 199 // vp9_rc_postencode_update_drop_frame() 200 // 201 // The majority of rate control parameters are only expected 202 // to be set in the vp9_rc_get_..._params() functions and 203 // updated during the vp9_rc_postencode_update...() functions. 204 // The only exceptions are vp9_rc_drop_frame() and 205 // vp9_rc_update_rate_correction_factors() functions. 206 207 // Functions to set parameters for encoding before the actual 208 // encode_frame_to_data_rate() function. 209 void vp9_rc_get_one_pass_vbr_params(struct VP9_COMP *cpi); 210 void vp9_rc_get_one_pass_cbr_params(struct VP9_COMP *cpi); 211 void vp9_rc_get_svc_params(struct VP9_COMP *cpi); 212 213 // Post encode update of the rate control parameters based 214 // on bytes used 215 void vp9_rc_postencode_update(struct VP9_COMP *cpi, uint64_t bytes_used); 216 // Post encode update of the rate control parameters for dropped frames 217 void vp9_rc_postencode_update_drop_frame(struct VP9_COMP *cpi); 218 219 // Updates rate correction factors 220 // Changes only the rate correction factors in the rate control structure. 221 void vp9_rc_update_rate_correction_factors(struct VP9_COMP *cpi); 222 223 // Decide if we should drop this frame: For 1-pass CBR. 224 // Changes only the decimation count in the rate control structure 225 int vp9_rc_drop_frame(struct VP9_COMP *cpi); 226 227 // Computes frame size bounds. 228 void vp9_rc_compute_frame_size_bounds(const struct VP9_COMP *cpi, 229 int this_frame_target, 230 int *frame_under_shoot_limit, 231 int *frame_over_shoot_limit); 232 233 // Picks q and q bounds given the target for bits 234 int vp9_rc_pick_q_and_bounds(const struct VP9_COMP *cpi, 235 int *bottom_index, 236 int *top_index); 237 238 // Estimates q to achieve a target bits per frame 239 int vp9_rc_regulate_q(const struct VP9_COMP *cpi, int target_bits_per_frame, 240 int active_best_quality, int active_worst_quality); 241 242 // Estimates bits per mb for a given qindex and correction factor. 243 int vp9_rc_bits_per_mb(FRAME_TYPE frame_type, int qindex, 244 double correction_factor, vpx_bit_depth_t bit_depth); 245 246 // Clamping utilities for bitrate targets for iframes and pframes. 247 int vp9_rc_clamp_iframe_target_size(const struct VP9_COMP *const cpi, 248 int target); 249 int vp9_rc_clamp_pframe_target_size(const struct VP9_COMP *const cpi, 250 int target); 251 // Utility to set frame_target into the RATE_CONTROL structure 252 // This function is called only from the vp9_rc_get_..._params() functions. 253 void vp9_rc_set_frame_target(struct VP9_COMP *cpi, int target); 254 255 // Computes a q delta (in "q index" terms) to get from a starting q value 256 // to a target q value 257 int vp9_compute_qdelta(const RATE_CONTROL *rc, double qstart, double qtarget, 258 vpx_bit_depth_t bit_depth); 259 260 // Computes a q delta (in "q index" terms) to get from a starting q value 261 // to a value that should equate to the given rate ratio. 262 int vp9_compute_qdelta_by_rate(const RATE_CONTROL *rc, FRAME_TYPE frame_type, 263 int qindex, double rate_target_ratio, 264 vpx_bit_depth_t bit_depth); 265 266 int vp9_frame_type_qdelta(const struct VP9_COMP *cpi, int rf_level, int q); 267 268 void vp9_rc_update_framerate(struct VP9_COMP *cpi); 269 270 void vp9_rc_set_gf_interval_range(const struct VP9_COMP *const cpi, 271 RATE_CONTROL *const rc); 272 273 void vp9_set_target_rate(struct VP9_COMP *cpi); 274 275 int vp9_resize_one_pass_cbr(struct VP9_COMP *cpi); 276 277 void vp9_avg_source_sad(struct VP9_COMP *cpi); 278 279 int vp9_encodedframe_overshoot(struct VP9_COMP *cpi, int frame_size, int *q); 280 281 #ifdef __cplusplus 282 } // extern "C" 283 #endif 284 285 #endif // VP9_ENCODER_VP9_RATECTRL_H_ 286