From f1ce050f44c7f91ee941155c7e080e6640b12781 Mon Sep 17 00:00:00 2001 From: paulwilkins Date: Mon, 4 Dec 2017 13:41:44 +0000 Subject: [PATCH] Bug fix for second reference stats. Immediately following a key frame the trailing second reference error in the first pass stats will be based on a reference frame from the prior key frame group and will thus usually be much larger. This fix eliminates that effect (which typically triggers a short arf group immediately after a key frame). It also changes the accounting for the first frame in each new arf group. This change gives large gains on a couple of clips that contain mid sequence key frames (e.g. 6% on 1080P tennis). Overall there was a net gain in PSNR and PSNR-HVS ~(0.05- 0.4%) and mixed results for SSIM (+/- 0.2%). Change-Id: I8e00538ac2c0b5c2e7e637903cac329ce5c2a375 --- vp9/encoder/vp9_firstpass.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/vp9/encoder/vp9_firstpass.c b/vp9/encoder/vp9_firstpass.c index b4c46014c..eefbdff51 100644 --- a/vp9/encoder/vp9_firstpass.c +++ b/vp9/encoder/vp9_firstpass.c @@ -2543,8 +2543,11 @@ static void define_gf_group(VP9_COMP *cpi, FIRSTPASS_STATS *this_frame) { // Update the accumulator for second ref error difference. // This is intended to give an indication of how much the coded error is // increasing over time. - sr_accumulator += (next_frame.sr_coded_error - next_frame.coded_error); - sr_accumulator = VPXMAX(0.0, sr_accumulator); + if (i == 1) { + sr_accumulator += next_frame.coded_error; + } else { + sr_accumulator += (next_frame.sr_coded_error - next_frame.coded_error); + } } // Break out conditions. -- 2.40.0