From b814e2d898a6d10019cf1419569ca221214641f5 Mon Sep 17 00:00:00 2001 From: paulwilkins Date: Wed, 16 Aug 2017 13:34:49 +0100 Subject: Prevent parameters that can cause invalid ARF groups. Having a very low "lag_in_frames" value could cause the encoder to create incorrect / corrupt ARF groups including displayed frames that update the ARF buffer and false overlay frames that are coded at low rate but are not actually overlays of a real ARF frame. This is linked to a reported unit test "slow down" where the chosen parameters (lag of 3 frames) gave rise to such "broken" ARF group(s). See also BUG=webm:1454 Change-Id: If52d0236243ed5552537d1ea9ed3fed8c867232c --- vp9/vp9_cx_iface.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'vp9/vp9_cx_iface.c') diff --git a/vp9/vp9_cx_iface.c b/vp9/vp9_cx_iface.c index 876aef3e6..7b6aa4bf5 100644 --- a/vp9/vp9_cx_iface.c +++ b/vp9/vp9_cx_iface.c @@ -191,6 +191,13 @@ static vpx_codec_err_t validate_config(vpx_codec_alg_priv_t *ctx, (MAX_LAG_BUFFERS - 1)); } + // For formation of valid ARF groups lag_in _frames should be 0 or greater + // than the max_gf_interval + 2 + if (cfg->g_lag_in_frames > 0 && extra_cfg->max_gf_interval > 0 && + cfg->g_lag_in_frames < extra_cfg->max_gf_interval + 2) { + ERROR("Set lag in frames to 0 (low delay) or >= (max-gf-interval + 2)"); + } + if (cfg->rc_resize_allowed == 1) { RANGE_CHECK(cfg, rc_scaled_width, 0, cfg->g_w); RANGE_CHECK(cfg, rc_scaled_height, 0, cfg->g_h); -- cgit v1.2.3