ref: 976f7f42c1ad1ff3cc0792572f9c4f41f05bb375
parent: 37d03809bfb523910b2a07a726a0dad82980047b
author: Marco <[email protected]>
date: Tue Apr 28 04:29:48 EDT 2015
VP8: For high overshoot, force drop frame and max-out QP. This allows rate control to react to content of current frame being encoded. Enabling this feature via the setting: screen_content_mode = 2. Change-Id: Ib2c6670551d96f4907495d5b7b76bb8c49e673db
--- a/vp8/encoder/onyx_if.c
+++ b/vp8/encoder/onyx_if.c
@@ -587,7 +587,8 @@
// Turn-off under certain conditions (i.e., away from key frame, and if
// we are at good quality (low Q) and most of the blocks were skipped-encoded
// in previous frame.
- if (Q >= 100) {+ int qp_thresh = (cpi->oxcf.screen_content_mode == 2) ? 80 : 100;
+ if (Q >= qp_thresh) {cpi->cyclic_refresh_mode_max_mbs_perframe =
(cpi->common.mb_rows * cpi->common.mb_cols) / 10;
} else if (cpi->frames_since_key > 250 &&
@@ -2011,6 +2012,8 @@
cpi->source_alt_ref_active = 0;
cpi->common.refresh_alt_ref_frame = 0;
+ cpi->force_maxqp = 0;
+
cpi->b_calculate_psnr = CONFIG_INTERNAL_STATS;
#if CONFIG_INTERNAL_STATS
cpi->b_calculate_ssimg = 0;
@@ -4184,7 +4187,10 @@
*/
if (cpi->cyclic_refresh_mode_enabled)
{- if (cpi->current_layer==0)
+ // Special case for screen_content_mode with golden frame updates.
+ int disable_cr_gf = (cpi->oxcf.screen_content_mode == 2 &&
+ cm->refresh_golden_frame);
+ if (cpi->current_layer == 0 && cpi->force_maxqp == 0 && !disable_cr_gf)
cyclic_background_refresh(cpi, Q, 0);
else
disable_segmentation(cpi);
@@ -4405,6 +4411,11 @@
#else
/* transform / motion compensation build reconstruction frame */
vp8_encode_frame(cpi);
+
+ if (cpi->oxcf.screen_content_mode == 2) {+ if (vp8_drop_encodedframe_overshoot(cpi, Q))
+ return;
+ }
cpi->projected_frame_size -= vp8_estimate_entropy_savings(cpi);
cpi->projected_frame_size = (cpi->projected_frame_size > 0) ? cpi->projected_frame_size : 0;
--- a/vp8/encoder/onyx_int.h
+++ b/vp8/encoder/onyx_int.h
@@ -526,6 +526,8 @@
// Measure of average squared difference between source and denoised signal.
int mse_source_denoised;
+ int force_maxqp;
+
#if CONFIG_MULTITHREAD
/* multithread data */
int * mt_current_mb_col;
--- a/vp8/encoder/ratectrl.c
+++ b/vp8/encoder/ratectrl.c
@@ -1215,6 +1215,11 @@
{int Q = cpi->active_worst_quality;
+ if (cpi->force_maxqp == 1) {+ cpi->active_worst_quality = cpi->worst_quality;
+ return cpi->worst_quality;
+ }
+
/* Reset Zbin OQ value */
cpi->mb.zbin_over_quant = 0;
@@ -1558,4 +1563,45 @@
}
}
return 1;
+}
+// If this just encoded frame (mcomp/transform/quant, but before loopfilter and
+// pack_bitstream) has large overshoot, and was not being encoded close to the
+// max QP, then drop this frame and force next frame to be encoded at max QP.
+// Condition this on 1 pass CBR with screen content mode and frame dropper off.
+// TODO(marpan): Should do this exit condition during the encode_frame
+// (i.e., halfway during the encoding of the frame) to save cycles.
+int vp8_drop_encodedframe_overshoot(VP8_COMP *cpi, int Q) {+ if (cpi->pass == 0 &&
+ cpi->oxcf.end_usage == USAGE_STREAM_FROM_SERVER &&
+ cpi->drop_frames_allowed == 0 &&
+ cpi->common.frame_type != KEY_FRAME) {+ // Note: the "projected_frame_size" from encode_frame() only gives estimate
+ // of mode/motion vector rate (in non-rd mode): so below we only require
+ // that projected_frame_size is somewhat greater than per-frame-bandwidth,
+ // but add additional condition with high threshold on prediction residual.
+
+ // QP threshold: only allow dropping if we are not close to qp_max.
+ int thresh_qp = 3 * cpi->worst_quality >> 2;
+ // Rate threshold, in bytes.
+ int thresh_rate = 2 * (cpi->av_per_frame_bandwidth >> 3);
+ // Threshold for the average (over all macroblocks) of the pixel-sum
+ // residual error over 16x16 block. Should add QP dependence on threshold?
+ int thresh_pred_err_mb = (256 << 4);
+ int pred_err_mb = cpi->mb.prediction_error / cpi->common.MBs;
+ if (Q < thresh_qp &&
+ cpi->projected_frame_size > thresh_rate &&
+ pred_err_mb > thresh_pred_err_mb) {+ // Drop this frame: advance frame counters, and set force_maxqp flag.
+ cpi->common.current_video_frame++;
+ cpi->frames_since_key++;
+ // Flag to indicate we will force next frame to be encoded at max QP.
+ cpi->force_maxqp = 1;
+ return 1;
+ } else {+ cpi->force_maxqp = 0;
+ return 0;
+ }
+ return 0;
+ }
+ return 0;
}
--- a/vp8/encoder/ratectrl.h
+++ b/vp8/encoder/ratectrl.h
@@ -30,6 +30,8 @@
/* return of 0 means drop frame */
extern int vp8_pick_frame_size(VP8_COMP *cpi);
+extern int vp8_drop_encodedframe_overshoot(VP8_COMP *cpi, int Q);
+
#ifdef __cplusplus
} // extern "C"
#endif
--- a/vp8/vp8_cx_iface.c
+++ b/vp8/vp8_cx_iface.c
@@ -199,7 +199,7 @@
RANGE_CHECK_HI(vp8_cfg, arnr_strength, 6);
RANGE_CHECK(vp8_cfg, arnr_type, 1, 3);
RANGE_CHECK(vp8_cfg, cq_level, 0, 63);
- RANGE_CHECK_BOOL(vp8_cfg, screen_content_mode);
+ RANGE_CHECK_HI(vp8_cfg, screen_content_mode, 2);
if (finalize && (cfg->rc_end_usage == VPX_CQ || cfg->rc_end_usage == VPX_Q))
RANGE_CHECK(vp8_cfg, cq_level,
cfg->rc_min_quantizer, cfg->rc_max_quantizer);
--- a/vpx/vp8cx.h
+++ b/vpx/vp8cx.h
@@ -327,6 +327,8 @@
/*!\brief Codec control function to set encoder screen content mode.
*
+ * 0: off, 1: On, 2: On with more aggressive rate control.
+ *
* Supported in codecs: VP8
*/
VP8E_SET_SCREEN_CONTENT_MODE,