avcodec/dvdec: Fix "left shift of negative value -254"

Fixes: dvdec_left_shift.avi Found-by: Piotr Bandurski <ami_stuff@o2.pl> Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
9 years ago · 93ac72a98d
parent 030c7f0309
commit 93ac72a98d
1 changed files with 1 additions and 1 deletions
--- a/libavcodec/dvdec.c
+++ b/libavcodec/dvdec.c
@ -347,7 +347,7 @@ retry:
                                    dct_mode                        * 22 * 64 +
                                    (quant + ff_dv_quant_offset[class1]) * 64];
            }
-            dc = dc << 2;
+            dc = dc * 4;
            /* convert to unsigned because 128 is not added in the
             * standard IDCT */
            dc                   += 1024;