From cf7c4732e5be5c881a49f778ba011ea5d656f66e Mon Sep 17 00:00:00 2001 From: Paul Wilkins <paulwilkins@google.com> Date: Mon, 10 Jan 2011 16:41:53 +0000 Subject: [PATCH] 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 --- vp8/encoder/firstpass.c | 15 ++++++++++++- vp8/encoder/onyx_if.c | 50 ++++++++++++++++++++++++----------------- 2 files changed, 43 insertions(+), 22 deletions(-) diff --git a/vp8/encoder/firstpass.c b/vp8/encoder/firstpass.c index 48899162d4..4d259c676d 100644 --- a/vp8/encoder/firstpass.c +++ b/vp8/encoder/firstpass.c @@ -989,6 +989,19 @@ static int estimate_max_q(VP8_COMP *cpi, double section_err, int section_target_ //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 @@ void vp8_second_pass(VP8_COMP *cpi) 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 diff --git a/vp8/encoder/onyx_if.c b/vp8/encoder/onyx_if.c index ee461c610a..2d9e8011b0 100644 --- a/vp8/encoder/onyx_if.c +++ b/vp8/encoder/onyx_if.c @@ -4442,30 +4442,38 @@ static void encode_frame_to_data_rate { 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; - } - - // 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; + // 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 0 @@ -4559,7 +4567,7 @@ static void encode_frame_to_data_rate 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 @@ static void encode_frame_to_data_rate (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 @@ static void encode_frame_to_data_rate 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 @@ static void encode_frame_to_data_rate (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, -- GitLab