av1_cx_iface.c: clarify allintra overrides
Add comments to explain why allintra overrides specific values,
so readers can understand why they're there in the first place.
Bug: aomedia:375221136
Change-Id: I68fde69a8456e6b50258ccdac89adfb75ef67809
diff --git a/av1/av1_cx_iface.c b/av1/av1_cx_iface.c
index 071a2fe..e9f9f2c 100644
--- a/av1/av1_cx_iface.c
+++ b/av1/av1_cx_iface.c
@@ -2867,7 +2867,13 @@
// However, if users set --enable-cdef, --qm-min, or --qm-max, either from
// the command line or aom_codec_control(), the encoder still respects it.
if (priv->cfg.g_usage == AOM_USAGE_ALL_INTRA) {
+ // CDEF has been found to blur images, so it's disabled in all-intra mode
priv->extra_cfg.enable_cdef = 0;
+ // These QM min/max values have been found to be optimal for images,
+ // when used with an alternative QM formula (see
+ // aom_get_qmlevel_allintra()).
+ // These values could also be beneficial for other usage modes, but
+ // further testing is required.
priv->extra_cfg.qm_min = DEFAULT_QM_FIRST_ALLINTRA;
priv->extra_cfg.qm_max = DEFAULT_QM_LAST_ALLINTRA;
}
