[FFmpeg-devel] [PATCH] make fast option with h264 actually do something..

Rich Felker dalias
Tue Feb 19 07:26:24 CET 2008

Currently, the FAST flag for h264 only affects motion functions for
non-ref frames, making it mostly useless. This patch makes it affect
all motion compensation. Benchmarks on my K6, using mplayer

Without fast: 17.6 sec
With current fast: 17.2 sec
With patch applied: 16.6 sec

I did not notice any visible corruption, but even if there is some,
that's the idea of the 'fast' flag...

Comments welcome.

-------------- next part --------------
Index: libavcodec/h264.c
--- libavcodec/h264.c	(revision 11441)
+++ libavcodec/h264.c	(working copy)
@@ -3814,7 +3814,7 @@
     s->dropable= h->nal_ref_idc == 0;
-    if((s->avctx->flags2 & CODEC_FLAG2_FAST) && !h->nal_ref_idc){
+    if((s->avctx->flags2 & CODEC_FLAG2_FAST)){
         s->me.qpel_put= s->dsp.put_2tap_qpel_pixels_tab;
         s->me.qpel_avg= s->dsp.avg_2tap_qpel_pixels_tab;

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