[FFmpeg-cvslog] avcodec/jpeg2000dwt: Fix undefined shifts of negative numbers

[Andreas Rheinhardt]

ffmpeg | branch: release/4.2 | Andreas Rheinhardt <andreas.rheinhardt at gmail.com> | Sat Sep 28 04:26:10 2019 +0200| [33093d3782cd4fb0d8c4b6f338e121e236d2a997] | committer: Andreas Rheinhardt

avcodec/jpeg2000dwt: Fix undefined shifts of negative numbers

Affected the vsynth*-jpeg2000 and the vsynth*-jpeg2000-97 FATE tests
(where * ranges over { 1, 2, 3, _lena }) as well as ticket #7983.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at gmail.com>
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
(cherry picked from commit 5cf593adcd79a7c9502dc2725e1f0681ada36aef)

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=33093d3782cd4fb0d8c4b6f338e121e236d2a997
---

 libavcodec/jpeg2000dwt.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libavcodec/jpeg2000dwt.c b/libavcodec/jpeg2000dwt.c
index badf0f8cd0..f418454ee9 100644
--- a/libavcodec/jpeg2000dwt.c
+++ b/libavcodec/jpeg2000dwt.c
@@ -255,7 +255,7 @@ static void dwt_encode97_int(DWTContext *s, int *t)
     line += 5;
 
     for (i = 0; i < w * h; i++)
-        t[i] <<= I_PRESHIFT;
+        t[i] *= 1 << I_PRESHIFT;
 
     for (lev = s->ndeclevels-1; lev >= 0; lev--){
         int lh = s->linelen[lev][0],