Cleanup decode_block_progressive()

Originally committed as revision 25543 to svn://svn.ffmpeg.org/ffmpeg/trunk
14 years ago · 7f4a1e8f6c
parent 614252863d
commit 7f4a1e8f6c
1 changed files with 7 additions and 7 deletions
--- a/libavcodec/mjpegdec.c
+++ b/libavcodec/mjpegdec.c
@ -506,13 +506,13 @@ static int decode_block_progressive(MJpegDecodeContext *s, DCTELEM *block, uint8
            if(run == 0xF){// ZRL - skip 15 coefficients
                i += 15;
            }else{
-                val = run;
-                run = (1 << run);
+                val = (1 << run);
+                if(run){
                    UPDATE_CACHE(re, &s->gb);
-                run += (GET_CACHE(re, &s->gb) >> (32 - val)) & (run - 1);
-                if(val)
-                    LAST_SKIP_BITS(re, &s->gb, val);
-                *EOBRUN = run - 1;
+                    val += NEG_USR32(GET_CACHE(re, &s->gb), run);
+                    LAST_SKIP_BITS(re, &s->gb, run);
+                }
+                *EOBRUN = val - 1;
                break;
            }
        }