[SCM] libav/experimental: optimizing unpack_coeffs()

siretart at users.alioth.debian.org siretart at users.alioth.debian.org
Sun Jun 30 15:43:38 UTC 2013


The following commit has been merged in the experimental branch:
commit 3c096ac7911fd51ea4bc602277f82ea222bfec6b
Author: Michael Niedermayer <michaelni at gmx.at>
Date:   Thu Apr 14 18:33:26 2005 +0000

    optimizing unpack_coeffs()
    
    Originally committed as revision 4127 to svn://svn.ffmpeg.org/ffmpeg/trunk

diff --git a/libavcodec/snow.c b/libavcodec/snow.c
index ee77f1c..c8d4d5c 100644
--- a/libavcodec/snow.c
+++ b/libavcodec/snow.c
@@ -1817,10 +1817,21 @@ static inline void unpack_coeffs(SnowContext *s, SubBand *b, SubBand * parent, i
                     int context= av_log2(/*ABS(ll) + */3*(l>>1) + (lt>>1) + (t&~1) + (rt>>1) + (p>>1));
 
                     v=get_rac(&s->c, &b->state[0][context]);
+                    if(v){
+                        v= 2*(get_symbol2(&s->c, b->state[context + 2], context-4) + 1);
+                        v+=get_rac(&s->c, &b->state[0][16 + 1 + 3 + quant3bA[l&0xFF] + 3*quant3bA[t&0xFF]]);
+                        
+                        b->x_coeff[index].x=x;
+                        b->x_coeff[index++].coeff= v;
+                    }
                 }else{
                     if(!run){
                         run= get_symbol2(&s->c, b->state[1], 3);
-                        v=1;
+                        v= 2*(get_symbol2(&s->c, b->state[0 + 2], 0-4) + 1);
+                        v+=get_rac(&s->c, &b->state[0][16 + 1 + 3]);
+                        
+                        b->x_coeff[index].x=x;
+                        b->x_coeff[index++].coeff= v;
                     }else{
                         run--;
                         v=0;
@@ -1835,14 +1846,6 @@ static inline void unpack_coeffs(SnowContext *s, SubBand *b, SubBand * parent, i
                         }
                     }
                 }
-                if(v){
-                    int context= av_log2(/*ABS(ll) + */3*(l>>1) + (lt>>1) + (t&~1) + (rt>>1) + (p>>1));
-                    v= 2*(get_symbol2(&s->c, b->state[context + 2], context-4) + 1);
-                    v+=get_rac(&s->c, &b->state[0][16 + 1 + 3 + quant3bA[l&0xFF] + 3*quant3bA[t&0xFF]]);
-                       
-                    b->x_coeff[index].x=x;
-                    b->x_coeff[index++].coeff= v;
-                }
             }
             b->x_coeff[index++].x= w+1; //end marker
             prev_index= prev2_index;

-- 
Libav/FFmpeg packaging



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