From 507ee87e3e24db80322944d8a2481d3db8b6beeb Mon Sep 17 00:00:00 2001 From: Marco Paniconi Date: Wed, 22 Feb 2012 14:39:17 -0800 Subject: [PATCH] Remove the frame rate factor for key frame size. When temporal layers is used (i.e., number_of_layers > 1), we don't use the frame rate boost for setting the key frame target size. The factor was forcing the target size to be always at its minimum (2* per_frame_bandwidth) for low frame rates (i.e., base layer frame rate). Generally we should modify or remove this frame rate factor; for now we turn if off for number_of_layers > 1. Change-Id: Ia5acf406c9b2f634d30ac2473adc7b9bf2e7e6c6 --- vp8/encoder/ratectrl.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/vp8/encoder/ratectrl.c b/vp8/encoder/ratectrl.c index 1c43c1171..f4ed30026 100644 --- a/vp8/encoder/ratectrl.c +++ b/vp8/encoder/ratectrl.c @@ -392,10 +392,16 @@ static void calc_iframe_target_size(VP8_COMP *cpi) int Q = (cpi->common.frame_flags & FRAMEFLAGS_KEY) ? cpi->avg_frame_qindex : cpi->ni_av_qi; - // Boost depends somewhat on frame rate - kf_boost = (int)(2 * cpi->output_frame_rate - 16); + // Boost depends somewhat on frame rate: only used for 1 layer case. + if (cpi->oxcf.number_of_layers == 1) { + kf_boost = (int)(2 * cpi->output_frame_rate - 16); + } + else { + // Initial factor: set target size to: |2.5 * per_frame_bandwidth|. + kf_boost = 24; + } - // adjustment up based on q + // adjustment up based on q: this factor ranges from ~1.2 to 2.2. kf_boost = kf_boost * kf_boost_qadjustment[Q] / 100; // frame separation adjustment ( down) @@ -403,6 +409,7 @@ static void calc_iframe_target_size(VP8_COMP *cpi) kf_boost = (int)(kf_boost * cpi->frames_since_key / (cpi->output_frame_rate / 2)); + // Minimal target size is |2* per_frame_bandwidth|. if (kf_boost < 16) kf_boost = 16; -- 2.40.0