void vp10_setup_in_frame_q_adj(VP10_COMP *cpi) {
VP10_COMMON *const cm = &cpi->common;
struct segmentation *const seg = &cm->seg;
// Make SURE use of floating point in this function is safe.
vpx_clear_system_state();
if (frame_is_intra_only(cm) || cm->error_resilient_mode ||
cpi->refresh_alt_ref_frame ||
(cpi->refresh_golden_frame && !cpi->rc.is_src_frame_alt_ref)) {
int segment;
const int aq_strength = get_aq_c_strength(cm->base_qindex, cm->bit_depth);
// Clear down the segment map.
memset(cpi->segmentation_map, DEFAULT_AQ2_SEG, cm->mi_rows * cm->mi_cols);
vp10_clearall_segfeatures(seg);
// Segmentation only makes sense if the target bits per SB is above a
// threshold. Below this the overheads will usually outweigh any benefit.
if (cpi->rc.sb64_target_rate < 256) {
vp10_disable_segmentation(seg);
return;
}
vp10_enable_segmentation(seg);
// Select delta coding method.
seg->abs_delta = SEGMENT_DELTADATA;
// Default segment "Q" feature is disabled so it defaults to the baseline Q.
vp10_disable_segfeature(seg, DEFAULT_AQ2_SEG, SEG_LVL_ALT_Q);
// Use some of the segments for in frame Q adjustment.
for (segment = 0; segment < AQ_C_SEGMENTS; ++segment) {
int qindex_delta;
if (segment == DEFAULT_AQ2_SEG) continue;
qindex_delta = vp10_compute_qdelta_by_rate(
&cpi->rc, cm->frame_type, cm->base_qindex,
aq_c_q_adj_factor[aq_strength][segment], cm->bit_depth);
// For AQ complexity mode, we dont allow Q0 in a segment if the base
// Q is not 0. Q0 (lossless) implies 4x4 only and in AQ mode 2 a segment
// Q delta is sometimes applied without going back around the rd loop.
// This could lead to an illegal combination of partition size and q.
if ((cm->base_qindex != 0) && ((cm->base_qindex + qindex_delta) == 0)) {
qindex_delta = -cm->base_qindex + 1;
}
if ((cm->base_qindex + qindex_delta) > 0) {
vp10_enable_segfeature(seg, segment, SEG_LVL_ALT_Q);
vp10_set_segdata(seg, segment, SEG_LVL_ALT_Q, qindex_delta);
}
}
}
}
// Setup cyclic background refresh: set delta q and segmentation map.
void vp10_cyclic_refresh_setup(VP10_COMP *const cpi) {
VP10_COMMON *const cm = &cpi->common;
const RATE_CONTROL *const rc = &cpi->rc;
CYCLIC_REFRESH *const cr = cpi->cyclic_refresh;
struct segmentation *const seg = &cm->seg;
const int apply_cyclic_refresh = apply_cyclic_refresh_bitrate(cm, rc);
if (cm->current_video_frame == 0)
cr->low_content_avg = 0.0;
// Don't apply refresh on key frame or enhancement layer frames.
if (!apply_cyclic_refresh || cm->frame_type == KEY_FRAME) {
// Set segmentation map to 0 and disable.
unsigned char *const seg_map = cpi->segmentation_map;
memset(seg_map, 0, cm->mi_rows * cm->mi_cols);
vp10_disable_segmentation(&cm->seg);
if (cm->frame_type == KEY_FRAME) {
memset(cr->last_coded_q_map, MAXQ,
cm->mi_rows * cm->mi_cols * sizeof(*cr->last_coded_q_map));
cr->sb_index = 0;
}
return;
} else {
int qindex_delta = 0;
int qindex2;
const double q = vp10_convert_qindex_to_q(cm->base_qindex, cm->bit_depth);
vpx_clear_system_state();
// Set rate threshold to some multiple (set to 2 for now) of the target
// rate (target is given by sb64_target_rate and scaled by 256).
cr->thresh_rate_sb = ((int64_t)(rc->sb64_target_rate) << 8) << 2;
// Distortion threshold, quadratic in Q, scale factor to be adjusted.
// q will not exceed 457, so (q * q) is within 32bit; see:
// vp10_convert_qindex_to_q(), vp10_ac_quant(), ac_qlookup*[].
cr->thresh_dist_sb = ((int64_t)(q * q)) << 2;
// Set up segmentation.
// Clear down the segment map.
vp10_enable_segmentation(&cm->seg);
vp10_clearall_segfeatures(seg);
// Select delta coding method.
seg->abs_delta = SEGMENT_DELTADATA;
// Note: setting temporal_update has no effect, as the seg-map coding method
// (temporal or spatial) is determined in vp10_choose_segmap_coding_method(),
// based on the coding cost of each method. For error_resilient mode on the
// last_frame_seg_map is set to 0, so if temporal coding is used, it is
// relative to 0 previous map.
// seg->temporal_update = 0;
// Segment BASE "Q" feature is disabled so it defaults to the baseline Q.
vp10_disable_segfeature(seg, CR_SEGMENT_ID_BASE, SEG_LVL_ALT_Q);
// Use segment BOOST1 for in-frame Q adjustment.
vp10_enable_segfeature(seg, CR_SEGMENT_ID_BOOST1, SEG_LVL_ALT_Q);
// Use segment BOOST2 for more aggressive in-frame Q adjustment.
vp10_enable_segfeature(seg, CR_SEGMENT_ID_BOOST2, SEG_LVL_ALT_Q);
// Set the q delta for segment BOOST1.
qindex_delta = compute_deltaq(cpi, cm->base_qindex, cr->rate_ratio_qdelta);
cr->qindex_delta[1] = qindex_delta;
// Compute rd-mult for segment BOOST1.
qindex2 = clamp(cm->base_qindex + cm->y_dc_delta_q + qindex_delta, 0, MAXQ);
cr->rdmult = vp10_compute_rd_mult(cpi, qindex2);
vp10_set_segdata(seg, CR_SEGMENT_ID_BOOST1, SEG_LVL_ALT_Q, qindex_delta);
// Set a more aggressive (higher) q delta for segment BOOST2.
qindex_delta = compute_deltaq(
cpi, cm->base_qindex,
VPXMIN(CR_MAX_RATE_TARGET_RATIO,
0.1 * cr->rate_boost_fac * cr->rate_ratio_qdelta));
cr->qindex_delta[2] = qindex_delta;
vp10_set_segdata(seg, CR_SEGMENT_ID_BOOST2, SEG_LVL_ALT_Q, qindex_delta);
// Update the segmentation and refresh map.
cyclic_refresh_update_map(cpi);
}
}