[FFmpeg-cvslog] r21875 - trunk/libavcodec/h264_cabac.c

[michael]

Author: michael
Date: Thu Feb 18 13:13:21 2010
New Revision: 21875

Log:
Speedup decode_cabac_field_decoding_flag() by 9 cpu cycles.

Modified:
   trunk/libavcodec/h264_cabac.c

Modified: trunk/libavcodec/h264_cabac.c
==============================================================================
--- trunk/libavcodec/h264_cabac.c	Thu Feb 18 01:19:50 2010	(r21874)
+++ trunk/libavcodec/h264_cabac.c	Thu Feb 18 13:13:21 2010	(r21875)
@@ -707,12 +707,11 @@ void ff_h264_init_cabac_states(H264Conte
 
 static int decode_cabac_field_decoding_flag(H264Context *h) {
     MpegEncContext * const s = &h->s;
-    const long mba_xy = h->mb_xy - 1L;
     const long mbb_xy = h->mb_xy - 2L*s->mb_stride;
 
     unsigned long ctx = 0;
 
-    ctx += (s->current_picture.mb_type[mba_xy]>>7)&(h->slice_table[mba_xy] == h->slice_num);
+    ctx += h->mb_field_decoding_flag & !!s->mb_x; //for FMO:(s->current_picture.mb_type[mba_xy]>>7)&(h->slice_table[mba_xy] == h->slice_num);
     ctx += (s->current_picture.mb_type[mbb_xy]>>7)&(h->slice_table[mbb_xy] == h->slice_num);
 
     return get_cabac_noinline( &h->cabac, &(h->cabac_state+70)[ctx] );