Set our own default cfg.rc_end_usage value (#950)
Do not rely on libaom's default cfg.rc_end_usage value. Set our own
default value explicitly, even when it is the same as libaom's default.
This change allows users to remove "-a end-usage=q" from their avifenc
command line.
diff --git a/src/codec_aom.c b/src/codec_aom.c
index 4a5a7b1..e9360ef 100644
--- a/src/codec_aom.c
+++ b/src/codec_aom.c
@@ -591,6 +591,26 @@
return AVIF_RESULT_UNKNOWN_ERROR;
}
+ // Set our own default cfg.rc_end_usage value, which may differ from libaom's default.
+ switch (aomUsage) {
+ case AOM_USAGE_GOOD_QUALITY:
+ // libaom's default is AOM_VBR. Change the default to AOM_Q since we don't need to
+ // hit a certain target bit rate. It's easier to control the worst quality in Q
+ // mode.
+ cfg.rc_end_usage = AOM_Q;
+ break;
+ case AOM_USAGE_REALTIME:
+ // For real-time mode we need to use CBR rate control mode. AOM_Q doesn't fit the
+ // rate control requirements for real-time mode. CBR does.
+ cfg.rc_end_usage = AOM_CBR;
+ break;
+#if defined(AOM_USAGE_ALL_INTRA)
+ case AOM_USAGE_ALL_INTRA:
+ cfg.rc_end_usage = AOM_Q;
+ break;
+#endif
+ }
+
// Profile 0. 8-bit and 10-bit 4:2:0 and 4:0:0 only.
// Profile 1. 8-bit and 10-bit 4:4:4
// Profile 2. 8-bit and 10-bit 4:2:2
@@ -637,9 +657,7 @@
cfg.g_limit = 1;
// Use the default settings of the new AOM_USAGE_ALL_INTRA (added in
- // https://crbug.com/aomedia/2959). Note that AOM_USAGE_ALL_INTRA
- // also sets cfg.rc_end_usage to AOM_Q by default, which we do not
- // set here.
+ // https://crbug.com/aomedia/2959).
//
// Set g_lag_in_frames to 0 to reduce the number of frame buffers
// (from 20 to 2) in libaom's lookahead structure. This reduces
