rtc: Fix to rate control reset under resize
Refactor the resetting of the rate control
under spatial resizing, allowing it to be used
for both dynamic resize and forced resize from
user (via SET_SCALEMODE).
Adjust the logic, fixing some issues and in
particular tune it to avoid big overshoot when
scale goes back up.
Change-Id: I936351b0d3d3696b284167e7bd946102bb3a5fd5
diff --git a/av1/encoder/ratectrl.c b/av1/encoder/ratectrl.c
index 93f5b1c..afc801e 100644
--- a/av1/encoder/ratectrl.c
+++ b/av1/encoder/ratectrl.c
@@ -2399,6 +2399,60 @@
return gf_update;
}
+static void resize_reset_rc(AV1_COMP *cpi, int resize_width, int resize_height,
+ int prev_width, int prev_height) {
+ RATE_CONTROL *const rc = &cpi->rc;
+ SVC *const svc = &cpi->svc;
+ double tot_scale_change = 1.0;
+ int target_bits_per_frame;
+ int active_worst_quality;
+ int qindex;
+ tot_scale_change = (double)(resize_width * resize_height) /
+ (double)(prev_width * prev_height);
+ // Reset buffer level to optimal, update target size.
+ rc->buffer_level = rc->optimal_buffer_level;
+ rc->bits_off_target = rc->optimal_buffer_level;
+ rc->this_frame_target =
+ av1_calc_pframe_target_size_one_pass_cbr(cpi, INTER_FRAME);
+ target_bits_per_frame = rc->this_frame_target;
+ if (tot_scale_change > 4.0)
+ rc->avg_frame_qindex[INTER_FRAME] = rc->worst_quality;
+ else if (tot_scale_change > 1.0)
+ rc->avg_frame_qindex[INTER_FRAME] =
+ (rc->avg_frame_qindex[INTER_FRAME] + rc->worst_quality) >> 1;
+ active_worst_quality = calc_active_worst_quality_no_stats_cbr(cpi);
+ qindex = av1_rc_regulate_q(cpi, target_bits_per_frame, rc->best_quality,
+ active_worst_quality, resize_width, resize_height);
+ // If resize is down, check if projected q index is close to worst_quality,
+ // and if so, reduce the rate correction factor (since likely can afford
+ // lower q for resized frame).
+ if (tot_scale_change < 1.0 && qindex > 90 * cpi->rc.worst_quality / 100)
+ rc->rate_correction_factors[INTER_NORMAL] *= 0.85;
+ // Apply the same rate control reset to all temporal layers.
+ for (int tl = 0; tl < svc->number_temporal_layers; tl++) {
+ LAYER_CONTEXT *lc = NULL;
+ lc = &svc->layer_context[svc->spatial_layer_id *
+ svc->number_temporal_layers +
+ tl];
+ lc->rc.resize_state = rc->resize_state;
+ lc->rc.buffer_level = lc->rc.optimal_buffer_level;
+ lc->rc.bits_off_target = lc->rc.optimal_buffer_level;
+ lc->rc.rate_correction_factors[INTER_FRAME] =
+ rc->rate_correction_factors[INTER_FRAME];
+ }
+ // If resize is back up: check if projected q index is too much above the
+ // previous index, and if so, reduce the rate correction factor
+ // (since prefer to keep q for resized frame at least closet to previous q).
+ // Also check if projected qindex is close to previous qindex, if so
+ // increase correction factor (to push qindex higher and avoid overshoot).
+ if (tot_scale_change >= 1.0) {
+ if (tot_scale_change < 4.0 && qindex > 130 * rc->last_q[INTER_FRAME] / 100)
+ rc->rate_correction_factors[INTER_NORMAL] *= 0.8;
+ if (qindex <= 120 * rc->last_q[INTER_FRAME] / 100)
+ rc->rate_correction_factors[INTER_NORMAL] *= 2.0;
+ }
+}
+
/*!\brief ChecK for resize based on Q, for 1 pass real-time mode.
*
* Check if we should resize, based on average QP from past x frames.
@@ -2476,15 +2530,10 @@
// If decision is to resize, reset some quantities, and check is we should
// reduce rate correction factor,
if (resize_action != NO_RESIZE) {
- SVC *const svc = &cpi->svc;
- LAYER_CONTEXT *lc = NULL;
int resize_width = cpi->oxcf.frm_dim_cfg.width;
int resize_height = cpi->oxcf.frm_dim_cfg.height;
int resize_scale_num = 1;
int resize_scale_den = 1;
- int target_bits_per_frame;
- int active_worst_quality;
- int qindex, tl, tot_scale_change;
if (resize_action == DOWN_THREEFOUR || resize_action == UP_THREEFOUR) {
resize_scale_num = 3;
resize_scale_den = 4;
@@ -2494,44 +2543,7 @@
}
resize_width = resize_width * resize_scale_num / resize_scale_den;
resize_height = resize_height * resize_scale_num / resize_scale_den;
- tot_scale_change = (resize_scale_den * resize_scale_den) /
- (resize_scale_num * resize_scale_num);
- // Reset buffer level to optimal, update target size.
- rc->buffer_level = rc->optimal_buffer_level;
- rc->bits_off_target = rc->optimal_buffer_level;
- rc->this_frame_target =
- av1_calc_pframe_target_size_one_pass_cbr(cpi, INTER_FRAME);
- // Get the projected qindex, based on the scaled target frame size (scaled
- // so target_bits_per_mb in av1_rc_regulate_q will be correct target).
- target_bits_per_frame = (resize_action >= 0)
- ? rc->this_frame_target * tot_scale_change
- : rc->this_frame_target / tot_scale_change;
- active_worst_quality = calc_active_worst_quality_no_stats_cbr(cpi);
- qindex =
- av1_rc_regulate_q(cpi, target_bits_per_frame, rc->best_quality,
- active_worst_quality, resize_width, resize_height);
- // If resize is down, check if projected q index is close to worst_quality,
- // and if so, reduce the rate correction factor (since likely can afford
- // lower q for resized frame).
- if (resize_action > 0 && qindex > 90 * cpi->rc.worst_quality / 100)
- rc->rate_correction_factors[INTER_NORMAL] *= 0.85;
- // Apply the same rate control reset to all temporal layers.
- for (tl = 0; tl < svc->number_temporal_layers; tl++) {
- lc = &svc->layer_context[svc->spatial_layer_id *
- svc->number_temporal_layers +
- tl];
- lc->rc.resize_state = rc->resize_state;
- lc->rc.buffer_level = lc->rc.optimal_buffer_level;
- lc->rc.bits_off_target = lc->rc.optimal_buffer_level;
- lc->rc.rate_correction_factors[INTER_FRAME] =
- rc->rate_correction_factors[INTER_FRAME];
- }
- // If resize is back up, check if projected q index is too much above the
- // current base_qindex, and if so, reduce the rate correction factor
- // (since prefer to keep q for resized frame at least close to previous q).
- if (resize_action < 0 && qindex > 130 * rc->last_q[INTER_FRAME] / 100) {
- rc->rate_correction_factors[INTER_NORMAL] *= 0.9;
- }
+ resize_reset_rc(cpi, resize_width, resize_height, cm->width, cm->height);
}
return;
}
@@ -2543,6 +2555,8 @@
AV1_COMMON *const cm = &cpi->common;
GF_GROUP *const gf_group = &cpi->gf_group;
SVC *const svc = &cpi->svc;
+ ResizePendingParams *const resize_pending_params =
+ &cpi->resize_pending_params;
int gf_update = 0;
int target;
const int layer =
@@ -2589,8 +2603,6 @@
// Check for dynamic resize, for single spatial layer for now.
// For temporal layers only check on base temporal layer.
if (cpi->oxcf.resize_cfg.resize_mode == RESIZE_DYNAMIC) {
- ResizePendingParams *const resize_pending_params =
- &cpi->resize_pending_params;
if (svc->number_spatial_layers == 1 && svc->temporal_layer_id == 0)
dynamic_resize_one_pass_cbr(cpi);
if (rc->resize_state == THREE_QUARTER) {
@@ -2604,6 +2616,11 @@
resize_pending_params->width = cpi->oxcf.frm_dim_cfg.width;
resize_pending_params->height = cpi->oxcf.frm_dim_cfg.height;
}
+ } else if (resize_pending_params->width && resize_pending_params->height &&
+ (cpi->common.width != resize_pending_params->width ||
+ cpi->common.height != resize_pending_params->height)) {
+ resize_reset_rc(cpi, resize_pending_params->width,
+ resize_pending_params->height, cm->width, cm->height);
}
// Set the GF interval and update flag.
gf_update = set_gf_interval_update_onepass_rt(cpi, frame_params->frame_type);
