1 /* 2 * Copyright (c) 2014 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 #include <limits.h> 12 #include <math.h> 13 14 #include "vpx_dsp/vpx_dsp_common.h" 15 #include "vpx_ports/system_state.h" 16 17 #include "vp9/encoder/vp9_aq_cyclicrefresh.h" 18 19 #include "vp9/common/vp9_seg_common.h" 20 21 #include "vp9/encoder/vp9_ratectrl.h" 22 #include "vp9/encoder/vp9_segmentation.h" 23 24 CYCLIC_REFRESH *vp9_cyclic_refresh_alloc(int mi_rows, int mi_cols) { 25 size_t last_coded_q_map_size; 26 size_t consec_zero_mv_size; 27 CYCLIC_REFRESH *const cr = vpx_calloc(1, sizeof(*cr)); 28 if (cr == NULL) 29 return NULL; 30 31 cr->map = vpx_calloc(mi_rows * mi_cols, sizeof(*cr->map)); 32 if (cr->map == NULL) { 33 vpx_free(cr); 34 return NULL; 35 } 36 last_coded_q_map_size = mi_rows * mi_cols * sizeof(*cr->last_coded_q_map); 37 cr->last_coded_q_map = vpx_malloc(last_coded_q_map_size); 38 if (cr->last_coded_q_map == NULL) { 39 vpx_free(cr); 40 return NULL; 41 } 42 assert(MAXQ <= 255); 43 memset(cr->last_coded_q_map, MAXQ, last_coded_q_map_size); 44 45 consec_zero_mv_size = mi_rows * mi_cols * sizeof(*cr->consec_zero_mv); 46 cr->consec_zero_mv = vpx_malloc(consec_zero_mv_size); 47 if (cr->consec_zero_mv == NULL) { 48 vpx_free(cr); 49 return NULL; 50 } 51 memset(cr->consec_zero_mv, 0, consec_zero_mv_size); 52 return cr; 53 } 54 55 void vp9_cyclic_refresh_free(CYCLIC_REFRESH *cr) { 56 vpx_free(cr->map); 57 vpx_free(cr->last_coded_q_map); 58 vpx_free(cr->consec_zero_mv); 59 vpx_free(cr); 60 } 61 62 // Check if we should turn off cyclic refresh based on bitrate condition. 63 static int apply_cyclic_refresh_bitrate(const VP9_COMMON *cm, 64 const RATE_CONTROL *rc) { 65 // Turn off cyclic refresh if bits available per frame is not sufficiently 66 // larger than bit cost of segmentation. Segment map bit cost should scale 67 // with number of seg blocks, so compare available bits to number of blocks. 68 // Average bits available per frame = avg_frame_bandwidth 69 // Number of (8x8) blocks in frame = mi_rows * mi_cols; 70 const float factor = 0.25; 71 const int number_blocks = cm->mi_rows * cm->mi_cols; 72 // The condition below corresponds to turning off at target bitrates: 73 // (at 30fps), ~12kbps for CIF, 36kbps for VGA, 100kps for HD/720p. 74 // Also turn off at very small frame sizes, to avoid too large fraction of 75 // superblocks to be refreshed per frame. Threshold below is less than QCIF. 76 if (rc->avg_frame_bandwidth < factor * number_blocks || 77 number_blocks / 64 < 5) 78 return 0; 79 else 80 return 1; 81 } 82 83 // Check if this coding block, of size bsize, should be considered for refresh 84 // (lower-qp coding). Decision can be based on various factors, such as 85 // size of the coding block (i.e., below min_block size rejected), coding 86 // mode, and rate/distortion. 87 static int candidate_refresh_aq(const CYCLIC_REFRESH *cr, 88 const MB_MODE_INFO *mbmi, 89 int64_t rate, 90 int64_t dist, 91 int bsize) { 92 MV mv = mbmi->mv[0].as_mv; 93 // Reject the block for lower-qp coding if projected distortion 94 // is above the threshold, and any of the following is true: 95 // 1) mode uses large mv 96 // 2) mode is an intra-mode 97 // Otherwise accept for refresh. 98 if (dist > cr->thresh_dist_sb && 99 (mv.row > cr->motion_thresh || mv.row < -cr->motion_thresh || 100 mv.col > cr->motion_thresh || mv.col < -cr->motion_thresh || 101 !is_inter_block(mbmi))) 102 return CR_SEGMENT_ID_BASE; 103 else if (bsize >= BLOCK_16X16 && 104 rate < cr->thresh_rate_sb && 105 is_inter_block(mbmi) && 106 mbmi->mv[0].as_int == 0 && 107 cr->rate_boost_fac > 10) 108 // More aggressive delta-q for bigger blocks with zero motion. 109 return CR_SEGMENT_ID_BOOST2; 110 else 111 return CR_SEGMENT_ID_BOOST1; 112 } 113 114 // Compute delta-q for the segment. 115 static int compute_deltaq(const VP9_COMP *cpi, int q, double rate_factor) { 116 const CYCLIC_REFRESH *const cr = cpi->cyclic_refresh; 117 const RATE_CONTROL *const rc = &cpi->rc; 118 int deltaq = vp9_compute_qdelta_by_rate(rc, cpi->common.frame_type, 119 q, rate_factor, 120 cpi->common.bit_depth); 121 if ((-deltaq) > cr->max_qdelta_perc * q / 100) { 122 deltaq = -cr->max_qdelta_perc * q / 100; 123 } 124 return deltaq; 125 } 126 127 // For the just encoded frame, estimate the bits, incorporating the delta-q 128 // from non-base segment. For now ignore effect of multiple segments 129 // (with different delta-q). Note this function is called in the postencode 130 // (called from rc_update_rate_correction_factors()). 131 int vp9_cyclic_refresh_estimate_bits_at_q(const VP9_COMP *cpi, 132 double correction_factor) { 133 const VP9_COMMON *const cm = &cpi->common; 134 const CYCLIC_REFRESH *const cr = cpi->cyclic_refresh; 135 int estimated_bits; 136 int mbs = cm->MBs; 137 int num8x8bl = mbs << 2; 138 // Weight for non-base segments: use actual number of blocks refreshed in 139 // previous/just encoded frame. Note number of blocks here is in 8x8 units. 140 double weight_segment1 = (double)cr->actual_num_seg1_blocks / num8x8bl; 141 double weight_segment2 = (double)cr->actual_num_seg2_blocks / num8x8bl; 142 // Take segment weighted average for estimated bits. 143 estimated_bits = (int)((1.0 - weight_segment1 - weight_segment2) * 144 vp9_estimate_bits_at_q(cm->frame_type, cm->base_qindex, mbs, 145 correction_factor, cm->bit_depth) + 146 weight_segment1 * 147 vp9_estimate_bits_at_q(cm->frame_type, 148 cm->base_qindex + cr->qindex_delta[1], mbs, 149 correction_factor, cm->bit_depth) + 150 weight_segment2 * 151 vp9_estimate_bits_at_q(cm->frame_type, 152 cm->base_qindex + cr->qindex_delta[2], mbs, 153 correction_factor, cm->bit_depth)); 154 return estimated_bits; 155 } 156 157 // Prior to encoding the frame, estimate the bits per mb, for a given q = i and 158 // a corresponding delta-q (for segment 1). This function is called in the 159 // rc_regulate_q() to set the base qp index. 160 // Note: the segment map is set to either 0/CR_SEGMENT_ID_BASE (no refresh) or 161 // to 1/CR_SEGMENT_ID_BOOST1 (refresh) for each superblock, prior to encoding. 162 int vp9_cyclic_refresh_rc_bits_per_mb(const VP9_COMP *cpi, int i, 163 double correction_factor) { 164 const VP9_COMMON *const cm = &cpi->common; 165 CYCLIC_REFRESH *const cr = cpi->cyclic_refresh; 166 int bits_per_mb; 167 int num8x8bl = cm->MBs << 2; 168 // Weight for segment prior to encoding: take the average of the target 169 // number for the frame to be encoded and the actual from the previous frame. 170 int target_refresh = cr->percent_refresh * cm->mi_rows * cm->mi_cols / 100; 171 double weight_segment = (double)((target_refresh + 172 cr->actual_num_seg1_blocks + cr->actual_num_seg2_blocks) >> 1) / 173 num8x8bl; 174 // Compute delta-q corresponding to qindex i. 175 int deltaq = compute_deltaq(cpi, i, cr->rate_ratio_qdelta); 176 // Take segment weighted average for bits per mb. 177 bits_per_mb = (int)((1.0 - weight_segment) * 178 vp9_rc_bits_per_mb(cm->frame_type, i, correction_factor, cm->bit_depth) + 179 weight_segment * 180 vp9_rc_bits_per_mb(cm->frame_type, i + deltaq, correction_factor, 181 cm->bit_depth)); 182 return bits_per_mb; 183 } 184 185 // Prior to coding a given prediction block, of size bsize at (mi_row, mi_col), 186 // check if we should reset the segment_id, and update the cyclic_refresh map 187 // and segmentation map. 188 void vp9_cyclic_refresh_update_segment(VP9_COMP *const cpi, 189 MB_MODE_INFO *const mbmi, 190 int mi_row, int mi_col, 191 BLOCK_SIZE bsize, 192 int64_t rate, 193 int64_t dist, 194 int skip) { 195 const VP9_COMMON *const cm = &cpi->common; 196 CYCLIC_REFRESH *const cr = cpi->cyclic_refresh; 197 const int bw = num_8x8_blocks_wide_lookup[bsize]; 198 const int bh = num_8x8_blocks_high_lookup[bsize]; 199 const int xmis = VPXMIN(cm->mi_cols - mi_col, bw); 200 const int ymis = VPXMIN(cm->mi_rows - mi_row, bh); 201 const int block_index = mi_row * cm->mi_cols + mi_col; 202 const int refresh_this_block = candidate_refresh_aq(cr, mbmi, rate, dist, 203 bsize); 204 // Default is to not update the refresh map. 205 int new_map_value = cr->map[block_index]; 206 int x = 0; int y = 0; 207 208 // If this block is labeled for refresh, check if we should reset the 209 // segment_id. 210 if (cyclic_refresh_segment_id_boosted(mbmi->segment_id)) { 211 mbmi->segment_id = refresh_this_block; 212 // Reset segment_id if it will be skipped. 213 if (skip) 214 mbmi->segment_id = CR_SEGMENT_ID_BASE; 215 } 216 217 // Update the cyclic refresh map, to be used for setting segmentation map 218 // for the next frame. If the block will be refreshed this frame, mark it 219 // as clean. The magnitude of the -ve influences how long before we consider 220 // it for refresh again. 221 if (cyclic_refresh_segment_id_boosted(mbmi->segment_id)) { 222 new_map_value = -cr->time_for_refresh; 223 } else if (refresh_this_block) { 224 // Else if it is accepted as candidate for refresh, and has not already 225 // been refreshed (marked as 1) then mark it as a candidate for cleanup 226 // for future time (marked as 0), otherwise don't update it. 227 if (cr->map[block_index] == 1) 228 new_map_value = 0; 229 } else { 230 // Leave it marked as block that is not candidate for refresh. 231 new_map_value = 1; 232 } 233 234 // Update entries in the cyclic refresh map with new_map_value, and 235 // copy mbmi->segment_id into global segmentation map. 236 for (y = 0; y < ymis; y++) 237 for (x = 0; x < xmis; x++) { 238 int map_offset = block_index + y * cm->mi_cols + x; 239 cr->map[map_offset] = new_map_value; 240 cpi->segmentation_map[map_offset] = mbmi->segment_id; 241 } 242 } 243 244 void vp9_cyclic_refresh_update_sb_postencode(VP9_COMP *const cpi, 245 const MB_MODE_INFO *const mbmi, 246 int mi_row, int mi_col, 247 BLOCK_SIZE bsize) { 248 const VP9_COMMON *const cm = &cpi->common; 249 CYCLIC_REFRESH *const cr = cpi->cyclic_refresh; 250 MV mv = mbmi->mv[0].as_mv; 251 const int bw = num_8x8_blocks_wide_lookup[bsize]; 252 const int bh = num_8x8_blocks_high_lookup[bsize]; 253 const int xmis = VPXMIN(cm->mi_cols - mi_col, bw); 254 const int ymis = VPXMIN(cm->mi_rows - mi_row, bh); 255 const int block_index = mi_row * cm->mi_cols + mi_col; 256 int x, y; 257 for (y = 0; y < ymis; y++) 258 for (x = 0; x < xmis; x++) { 259 int map_offset = block_index + y * cm->mi_cols + x; 260 // Inter skip blocks were clearly not coded at the current qindex, so 261 // don't update the map for them. For cases where motion is non-zero or 262 // the reference frame isn't the previous frame, the previous value in 263 // the map for this spatial location is not entirely correct. 264 if ((!is_inter_block(mbmi) || !mbmi->skip) && 265 mbmi->segment_id <= CR_SEGMENT_ID_BOOST2) { 266 cr->last_coded_q_map[map_offset] = clamp( 267 cm->base_qindex + cr->qindex_delta[mbmi->segment_id], 0, MAXQ); 268 } else if (is_inter_block(mbmi) && mbmi->skip && 269 mbmi->segment_id <= CR_SEGMENT_ID_BOOST2) { 270 cr->last_coded_q_map[map_offset] = VPXMIN( 271 clamp(cm->base_qindex + cr->qindex_delta[mbmi->segment_id], 272 0, MAXQ), 273 cr->last_coded_q_map[map_offset]); 274 // Update the consecutive zero/low_mv count. 275 if (is_inter_block(mbmi) && (abs(mv.row) < 8 && abs(mv.col) < 8)) { 276 if (cr->consec_zero_mv[map_offset] < 255) 277 cr->consec_zero_mv[map_offset]++; 278 } else { 279 cr->consec_zero_mv[map_offset] = 0; 280 } 281 } 282 } 283 } 284 285 // Update the actual number of blocks that were applied the segment delta q. 286 void vp9_cyclic_refresh_postencode(VP9_COMP *const cpi) { 287 VP9_COMMON *const cm = &cpi->common; 288 CYCLIC_REFRESH *const cr = cpi->cyclic_refresh; 289 unsigned char *const seg_map = cpi->segmentation_map; 290 int mi_row, mi_col; 291 cr->actual_num_seg1_blocks = 0; 292 cr->actual_num_seg2_blocks = 0; 293 for (mi_row = 0; mi_row < cm->mi_rows; mi_row++) 294 for (mi_col = 0; mi_col < cm->mi_cols; mi_col++) { 295 if (cyclic_refresh_segment_id( 296 seg_map[mi_row * cm->mi_cols + mi_col]) == CR_SEGMENT_ID_BOOST1) 297 cr->actual_num_seg1_blocks++; 298 else if (cyclic_refresh_segment_id( 299 seg_map[mi_row * cm->mi_cols + mi_col]) == CR_SEGMENT_ID_BOOST2) 300 cr->actual_num_seg2_blocks++; 301 } 302 } 303 304 // Set golden frame update interval, for non-svc 1 pass CBR mode. 305 void vp9_cyclic_refresh_set_golden_update(VP9_COMP *const cpi) { 306 RATE_CONTROL *const rc = &cpi->rc; 307 CYCLIC_REFRESH *const cr = cpi->cyclic_refresh; 308 // Set minimum gf_interval for GF update to a multiple (== 2) of refresh 309 // period. Depending on past encoding stats, GF flag may be reset and update 310 // may not occur until next baseline_gf_interval. 311 if (cr->percent_refresh > 0) 312 rc->baseline_gf_interval = 4 * (100 / cr->percent_refresh); 313 else 314 rc->baseline_gf_interval = 40; 315 } 316 317 // Update some encoding stats (from the just encoded frame). If this frame's 318 // background has high motion, refresh the golden frame. Otherwise, if the 319 // golden reference is to be updated check if we should NOT update the golden 320 // ref. 321 void vp9_cyclic_refresh_check_golden_update(VP9_COMP *const cpi) { 322 VP9_COMMON *const cm = &cpi->common; 323 CYCLIC_REFRESH *const cr = cpi->cyclic_refresh; 324 int mi_row, mi_col; 325 double fraction_low = 0.0; 326 int low_content_frame = 0; 327 328 MODE_INFO **mi = cm->mi_grid_visible; 329 RATE_CONTROL *const rc = &cpi->rc; 330 const int rows = cm->mi_rows, cols = cm->mi_cols; 331 int cnt1 = 0, cnt2 = 0; 332 int force_gf_refresh = 0; 333 334 for (mi_row = 0; mi_row < rows; mi_row++) { 335 for (mi_col = 0; mi_col < cols; mi_col++) { 336 int16_t abs_mvr = mi[0]->mbmi.mv[0].as_mv.row >= 0 ? 337 mi[0]->mbmi.mv[0].as_mv.row : -1 * mi[0]->mbmi.mv[0].as_mv.row; 338 int16_t abs_mvc = mi[0]->mbmi.mv[0].as_mv.col >= 0 ? 339 mi[0]->mbmi.mv[0].as_mv.col : -1 * mi[0]->mbmi.mv[0].as_mv.col; 340 341 // Calculate the motion of the background. 342 if (abs_mvr <= 16 && abs_mvc <= 16) { 343 cnt1++; 344 if (abs_mvr == 0 && abs_mvc == 0) 345 cnt2++; 346 } 347 mi++; 348 349 // Accumulate low_content_frame. 350 if (cr->map[mi_row * cols + mi_col] < 1) 351 low_content_frame++; 352 } 353 mi += 8; 354 } 355 356 // For video conference clips, if the background has high motion in current 357 // frame because of the camera movement, set this frame as the golden frame. 358 // Use 70% and 5% as the thresholds for golden frame refreshing. 359 // Also, force this frame as a golden update frame if this frame will change 360 // the resolution (resize_pending != 0). 361 if (cpi->resize_pending != 0 || 362 (cnt1 * 10 > (70 * rows * cols) && cnt2 * 20 < cnt1)) { 363 vp9_cyclic_refresh_set_golden_update(cpi); 364 rc->frames_till_gf_update_due = rc->baseline_gf_interval; 365 366 if (rc->frames_till_gf_update_due > rc->frames_to_key) 367 rc->frames_till_gf_update_due = rc->frames_to_key; 368 cpi->refresh_golden_frame = 1; 369 force_gf_refresh = 1; 370 } 371 372 fraction_low = 373 (double)low_content_frame / (rows * cols); 374 // Update average. 375 cr->low_content_avg = (fraction_low + 3 * cr->low_content_avg) / 4; 376 if (!force_gf_refresh && cpi->refresh_golden_frame == 1) { 377 // Don't update golden reference if the amount of low_content for the 378 // current encoded frame is small, or if the recursive average of the 379 // low_content over the update interval window falls below threshold. 380 if (fraction_low < 0.8 || cr->low_content_avg < 0.7) 381 cpi->refresh_golden_frame = 0; 382 // Reset for next internal. 383 cr->low_content_avg = fraction_low; 384 } 385 } 386 387 // Update the segmentation map, and related quantities: cyclic refresh map, 388 // refresh sb_index, and target number of blocks to be refreshed. 389 // The map is set to either 0/CR_SEGMENT_ID_BASE (no refresh) or to 390 // 1/CR_SEGMENT_ID_BOOST1 (refresh) for each superblock. 391 // Blocks labeled as BOOST1 may later get set to BOOST2 (during the 392 // encoding of the superblock). 393 static void cyclic_refresh_update_map(VP9_COMP *const cpi) { 394 VP9_COMMON *const cm = &cpi->common; 395 CYCLIC_REFRESH *const cr = cpi->cyclic_refresh; 396 unsigned char *const seg_map = cpi->segmentation_map; 397 int i, block_count, bl_index, sb_rows, sb_cols, sbs_in_frame; 398 int xmis, ymis, x, y; 399 int consec_zero_mv_thresh = 0; 400 int qindex_thresh = 0; 401 int count_sel = 0; 402 int count_tot = 0; 403 memset(seg_map, CR_SEGMENT_ID_BASE, cm->mi_rows * cm->mi_cols); 404 sb_cols = (cm->mi_cols + MI_BLOCK_SIZE - 1) / MI_BLOCK_SIZE; 405 sb_rows = (cm->mi_rows + MI_BLOCK_SIZE - 1) / MI_BLOCK_SIZE; 406 sbs_in_frame = sb_cols * sb_rows; 407 // Number of target blocks to get the q delta (segment 1). 408 block_count = cr->percent_refresh * cm->mi_rows * cm->mi_cols / 100; 409 // Set the segmentation map: cycle through the superblocks, starting at 410 // cr->mb_index, and stopping when either block_count blocks have been found 411 // to be refreshed, or we have passed through whole frame. 412 assert(cr->sb_index < sbs_in_frame); 413 i = cr->sb_index; 414 cr->target_num_seg_blocks = 0; 415 if (cpi->oxcf.content != VP9E_CONTENT_SCREEN) 416 consec_zero_mv_thresh = 100; 417 qindex_thresh = 418 cpi->oxcf.content == VP9E_CONTENT_SCREEN 419 ? vp9_get_qindex(&cm->seg, CR_SEGMENT_ID_BOOST2, cm->base_qindex) 420 : vp9_get_qindex(&cm->seg, CR_SEGMENT_ID_BOOST1, cm->base_qindex); 421 do { 422 int sum_map = 0; 423 // Get the mi_row/mi_col corresponding to superblock index i. 424 int sb_row_index = (i / sb_cols); 425 int sb_col_index = i - sb_row_index * sb_cols; 426 int mi_row = sb_row_index * MI_BLOCK_SIZE; 427 int mi_col = sb_col_index * MI_BLOCK_SIZE; 428 assert(mi_row >= 0 && mi_row < cm->mi_rows); 429 assert(mi_col >= 0 && mi_col < cm->mi_cols); 430 bl_index = mi_row * cm->mi_cols + mi_col; 431 // Loop through all 8x8 blocks in superblock and update map. 432 xmis = 433 VPXMIN(cm->mi_cols - mi_col, num_8x8_blocks_wide_lookup[BLOCK_64X64]); 434 ymis = 435 VPXMIN(cm->mi_rows - mi_row, num_8x8_blocks_high_lookup[BLOCK_64X64]); 436 for (y = 0; y < ymis; y++) { 437 for (x = 0; x < xmis; x++) { 438 const int bl_index2 = bl_index + y * cm->mi_cols + x; 439 // If the block is as a candidate for clean up then mark it 440 // for possible boost/refresh (segment 1). The segment id may get 441 // reset to 0 later if block gets coded anything other than ZEROMV. 442 if (cr->map[bl_index2] == 0) { 443 count_tot++; 444 if (cr->last_coded_q_map[bl_index2] > qindex_thresh || 445 cr->consec_zero_mv[bl_index2] < consec_zero_mv_thresh) { 446 sum_map++; 447 count_sel++; 448 } 449 } else if (cr->map[bl_index2] < 0) { 450 cr->map[bl_index2]++; 451 } 452 } 453 } 454 // Enforce constant segment over superblock. 455 // If segment is at least half of superblock, set to 1. 456 if (sum_map >= xmis * ymis / 2) { 457 for (y = 0; y < ymis; y++) 458 for (x = 0; x < xmis; x++) { 459 seg_map[bl_index + y * cm->mi_cols + x] = CR_SEGMENT_ID_BOOST1; 460 } 461 cr->target_num_seg_blocks += xmis * ymis; 462 } 463 i++; 464 if (i == sbs_in_frame) { 465 i = 0; 466 } 467 } while (cr->target_num_seg_blocks < block_count && i != cr->sb_index); 468 cr->sb_index = i; 469 cr->reduce_refresh = 0; 470 if (count_sel < (3 * count_tot) >> 2) 471 cr->reduce_refresh = 1; 472 } 473 474 // Set cyclic refresh parameters. 475 void vp9_cyclic_refresh_update_parameters(VP9_COMP *const cpi) { 476 const RATE_CONTROL *const rc = &cpi->rc; 477 const VP9_COMMON *const cm = &cpi->common; 478 CYCLIC_REFRESH *const cr = cpi->cyclic_refresh; 479 cr->percent_refresh = 10; 480 if (cr->reduce_refresh) 481 cr->percent_refresh = 5; 482 cr->max_qdelta_perc = 50; 483 cr->time_for_refresh = 0; 484 // Use larger delta-qp (increase rate_ratio_qdelta) for first few (~4) 485 // periods of the refresh cycle, after a key frame. 486 // Account for larger interval on base layer for temporal layers. 487 if (cr->percent_refresh > 0 && 488 rc->frames_since_key < (4 * cpi->svc.number_temporal_layers) * 489 (100 / cr->percent_refresh)) 490 cr->rate_ratio_qdelta = 3.0; 491 else 492 cr->rate_ratio_qdelta = 2.0; 493 // Adjust some parameters for low resolutions at low bitrates. 494 if (cm->width <= 352 && 495 cm->height <= 288 && 496 rc->avg_frame_bandwidth < 3400) { 497 cr->motion_thresh = 4; 498 cr->rate_boost_fac = 10; 499 } else { 500 cr->motion_thresh = 32; 501 cr->rate_boost_fac = 15; 502 } 503 if (cpi->svc.spatial_layer_id > 0) { 504 cr->motion_thresh = 4; 505 cr->rate_boost_fac = 12; 506 } 507 } 508 509 // Setup cyclic background refresh: set delta q and segmentation map. 510 void vp9_cyclic_refresh_setup(VP9_COMP *const cpi) { 511 VP9_COMMON *const cm = &cpi->common; 512 const RATE_CONTROL *const rc = &cpi->rc; 513 CYCLIC_REFRESH *const cr = cpi->cyclic_refresh; 514 struct segmentation *const seg = &cm->seg; 515 const int apply_cyclic_refresh = apply_cyclic_refresh_bitrate(cm, rc); 516 if (cm->current_video_frame == 0) 517 cr->low_content_avg = 0.0; 518 // Don't apply refresh on key frame or temporal enhancement layer frames. 519 if (!apply_cyclic_refresh || 520 (cm->frame_type == KEY_FRAME) || 521 (cpi->svc.temporal_layer_id > 0)) { 522 // Set segmentation map to 0 and disable. 523 unsigned char *const seg_map = cpi->segmentation_map; 524 memset(seg_map, 0, cm->mi_rows * cm->mi_cols); 525 vp9_disable_segmentation(&cm->seg); 526 if (cm->frame_type == KEY_FRAME) { 527 memset(cr->last_coded_q_map, MAXQ, 528 cm->mi_rows * cm->mi_cols * sizeof(*cr->last_coded_q_map)); 529 memset(cr->consec_zero_mv, 0, 530 cm->mi_rows * cm->mi_cols * sizeof(*cr->consec_zero_mv)); 531 cr->sb_index = 0; 532 } 533 return; 534 } else { 535 int qindex_delta = 0; 536 int qindex2; 537 const double q = vp9_convert_qindex_to_q(cm->base_qindex, cm->bit_depth); 538 vpx_clear_system_state(); 539 // Set rate threshold to some multiple (set to 2 for now) of the target 540 // rate (target is given by sb64_target_rate and scaled by 256). 541 cr->thresh_rate_sb = ((int64_t)(rc->sb64_target_rate) << 8) << 2; 542 // Distortion threshold, quadratic in Q, scale factor to be adjusted. 543 // q will not exceed 457, so (q * q) is within 32bit; see: 544 // vp9_convert_qindex_to_q(), vp9_ac_quant(), ac_qlookup*[]. 545 cr->thresh_dist_sb = ((int64_t)(q * q)) << 2; 546 547 // Set up segmentation. 548 // Clear down the segment map. 549 vp9_enable_segmentation(&cm->seg); 550 vp9_clearall_segfeatures(seg); 551 // Select delta coding method. 552 seg->abs_delta = SEGMENT_DELTADATA; 553 554 // Note: setting temporal_update has no effect, as the seg-map coding method 555 // (temporal or spatial) is determined in vp9_choose_segmap_coding_method(), 556 // based on the coding cost of each method. For error_resilient mode on the 557 // last_frame_seg_map is set to 0, so if temporal coding is used, it is 558 // relative to 0 previous map. 559 // seg->temporal_update = 0; 560 561 // Segment BASE "Q" feature is disabled so it defaults to the baseline Q. 562 vp9_disable_segfeature(seg, CR_SEGMENT_ID_BASE, SEG_LVL_ALT_Q); 563 // Use segment BOOST1 for in-frame Q adjustment. 564 vp9_enable_segfeature(seg, CR_SEGMENT_ID_BOOST1, SEG_LVL_ALT_Q); 565 // Use segment BOOST2 for more aggressive in-frame Q adjustment. 566 vp9_enable_segfeature(seg, CR_SEGMENT_ID_BOOST2, SEG_LVL_ALT_Q); 567 568 // Set the q delta for segment BOOST1. 569 qindex_delta = compute_deltaq(cpi, cm->base_qindex, cr->rate_ratio_qdelta); 570 cr->qindex_delta[1] = qindex_delta; 571 572 // Compute rd-mult for segment BOOST1. 573 qindex2 = clamp(cm->base_qindex + cm->y_dc_delta_q + qindex_delta, 0, MAXQ); 574 575 cr->rdmult = vp9_compute_rd_mult(cpi, qindex2); 576 577 vp9_set_segdata(seg, CR_SEGMENT_ID_BOOST1, SEG_LVL_ALT_Q, qindex_delta); 578 579 // Set a more aggressive (higher) q delta for segment BOOST2. 580 qindex_delta = compute_deltaq( 581 cpi, cm->base_qindex, 582 VPXMIN(CR_MAX_RATE_TARGET_RATIO, 583 0.1 * cr->rate_boost_fac * cr->rate_ratio_qdelta)); 584 cr->qindex_delta[2] = qindex_delta; 585 vp9_set_segdata(seg, CR_SEGMENT_ID_BOOST2, SEG_LVL_ALT_Q, qindex_delta); 586 587 // Reset if resoluton change has occurred. 588 if (cpi->resize_pending != 0) 589 vp9_cyclic_refresh_reset_resize(cpi); 590 591 // Update the segmentation and refresh map. 592 cyclic_refresh_update_map(cpi); 593 } 594 } 595 596 int vp9_cyclic_refresh_get_rdmult(const CYCLIC_REFRESH *cr) { 597 return cr->rdmult; 598 } 599 600 void vp9_cyclic_refresh_reset_resize(VP9_COMP *const cpi) { 601 const VP9_COMMON *const cm = &cpi->common; 602 CYCLIC_REFRESH *const cr = cpi->cyclic_refresh; 603 memset(cr->map, 0, cm->mi_rows * cm->mi_cols); 604 memset(cr->last_coded_q_map, MAXQ, cm->mi_rows * cm->mi_cols); 605 memset(cr->consec_zero_mv, 0, cm->mi_rows * cm->mi_cols); 606 cr->sb_index = 0; 607 cpi->refresh_golden_frame = 1; 608 } 609
