ref: cf7c4732e5be5c881a49f778ba011ea5d656f66e
parent: 405499d835a4a01fe09bc5ea01a2e7e77aaef8da
author: Paul Wilkins <paulwilkins@google.com>
date: Mon Jan 10 11:41:53 EST 2011
Two Pass VBR change Further experiment with restriction of the Q range. This uses the average non KF/GF/ARF quantizer, instead of just relying on the initial value. It is not such a strong constraint but there may be a reduced risk of rate misses. Change-Id: I424fe782a37a2f4e18c70805e240db55bfaa25ec
--- a/vp8/encoder/firstpass.c
+++ b/vp8/encoder/firstpass.c
@@ -989,6 +989,19 @@
//Q = cpi->oxcf.cq_target_quality;
}
+ // Adjust maxq_min_limit and maxq_max_limit limits based on
+ // averaga q observed in clip for non kf/gf.arf frames
+ // Give average a chance to settle though.
+ if ( (cpi->ni_frames >
+ ((unsigned int)cpi->total_stats->count >> 8)) &&
+ (cpi->ni_frames > 150) )
+ {+ cpi->maxq_max_limit = ((cpi->ni_av_qi + 32) < cpi->worst_quality)
+ ? (cpi->ni_av_qi + 32) : cpi->worst_quality;
+ cpi->maxq_min_limit = ((cpi->ni_av_qi - 32) > cpi->best_quality)
+ ? (cpi->ni_av_qi - 32) : cpi->best_quality;
+ }
+
return Q;
}
static int estimate_q(VP8_COMP *cpi, double section_err, int section_target_bandwitdh, int Height, int Width)
@@ -2121,7 +2134,7 @@
cpi->common.Width);
// Limit the maxq value returned subsequently.
- // This increases the risk of overspend if the initial
+ // This increases the risk of overspend or underspend if the initial
// estimate for the clip is bad, but helps prevent excessive
// variation in Q, especially near the end of a clip
// where for example a small overspend may cause Q to crash
--- a/vp8/encoder/onyx_if.c
+++ b/vp8/encoder/onyx_if.c
@@ -4442,30 +4442,38 @@
{cpi->ni_frames++;
- // Calculate the average Q for normal inter frames (not key or GFU frames)
- // This is used as a basis for setting active worst quality.
- if (cpi->ni_frames > 150)
+ // Calculate the average Q for normal inter frames (not key or GFU
+ // frames).
+ if ( cpi->pass == 2 )
{cpi->ni_tot_qi += Q;
cpi->ni_av_qi = (cpi->ni_tot_qi / cpi->ni_frames);
}
- // Early in the clip ... average the current frame Q value with the default
- // entered by the user as a dampening measure
else
{- cpi->ni_tot_qi += Q;
- cpi->ni_av_qi = ((cpi->ni_tot_qi / cpi->ni_frames) + cpi->worst_quality + 1) / 2;
- }
+ // Damp value for first few frames
+ if (cpi->ni_frames > 150 )
+ {+ cpi->ni_tot_qi += Q;
+ cpi->ni_av_qi = (cpi->ni_tot_qi / cpi->ni_frames);
+ }
+ // For one pass, early in the clip ... average the current frame Q
+ // value with the worstq entered by the user as a dampening measure
+ else
+ {+ cpi->ni_tot_qi += Q;
+ cpi->ni_av_qi = ((cpi->ni_tot_qi / cpi->ni_frames) + cpi->worst_quality + 1) / 2;
+ }
- // If the average Q is higher than what was used in the last frame
- // (after going through the recode loop to keep the frame size within range)
- // then use the last frame value - 1.
- // The -1 is designed to stop Q and hence the data rate, from progressively
- // falling away during difficult sections, but at the same time reduce the number of
- // itterations around the recode loop.
- if (Q > cpi->ni_av_qi)
- cpi->ni_av_qi = Q - 1;
-
+ // If the average Q is higher than what was used in the last frame
+ // (after going through the recode loop to keep the frame size within range)
+ // then use the last frame value - 1.
+ // The -1 is designed to stop Q and hence the data rate, from progressively
+ // falling away during difficult sections, but at the same time reduce the number of
+ // itterations around the recode loop.
+ if (Q > cpi->ni_av_qi)
+ cpi->ni_av_qi = Q - 1;
+ }
}
#if 0
@@ -4559,7 +4567,7 @@
if (cpi->total_coded_error_left != 0.0)
fprintf(f, "%10d %10d %10d %10d %10d %10d %10d %10d %6ld %6ld"
- "%6ld %6ld %5ld %5ld %5ld %8ld %8.2f %10d %10.3f"
+ "%6ld %6ld %6ld %5ld %5ld %5ld %8ld %8.2f %10d %10.3f"
"%10.3f %8ld\n",
cpi->common.current_video_frame, cpi->this_frame_target,
cpi->projected_frame_size,
@@ -4568,7 +4576,7 @@
(cpi->oxcf.starting_buffer_level-cpi->bits_off_target),
(int)cpi->total_actual_bits, cm->base_qindex,
cpi->active_best_quality, cpi->active_worst_quality,
- cpi->cq_target_quality, cpi->zbin_over_quant,
+ cpi->ni_av_qi, cpi->cq_target_quality, cpi->zbin_over_quant,
//cpi->avg_frame_qindex, cpi->zbin_over_quant,
cm->refresh_golden_frame, cm->refresh_alt_ref_frame,
cm->frame_type, cpi->gfu_boost,
@@ -4578,7 +4586,7 @@
cpi->tot_recode_hits);
else
fprintf(f, "%10d %10d %10d %10d %10d %10d %10d %10d %6ld %6ld"
- "%6ld %6ld %5ld %5ld %5ld %8ld %8.2f %10d %10.3f"
+ "%6ld %6ld %6ld %5ld %5ld %5ld %8ld %8.2f %10d %10.3f"
"%8ld\n",
cpi->common.current_video_frame,
cpi->this_frame_target, cpi->projected_frame_size,
@@ -4587,7 +4595,7 @@
(cpi->oxcf.starting_buffer_level-cpi->bits_off_target),
(int)cpi->total_actual_bits, cm->base_qindex,
cpi->active_best_quality, cpi->active_worst_quality,
- cpi->cq_target_quality, cpi->zbin_over_quant,
+ cpi->ni_av_qi, cpi->cq_target_quality, cpi->zbin_over_quant,
//cpi->avg_frame_qindex, cpi->zbin_over_quant,
cm->refresh_golden_frame, cm->refresh_alt_ref_frame,
cm->frame_type, cpi->gfu_boost,