[FFmpeg-cvslog] jpeg2000: fix overflow in dequantization
Michael Niedermayer
git at videolan.org
Sat Jul 13 12:46:48 CEST 2013
ffmpeg | branch: master | Michael Niedermayer <michaelni at gmx.at> | Sat Jul 13 02:24:56 2013 +0200| [f57119b8e58cb5437c3ab40d797293ecb9b4a894] | committer: Michael Niedermayer
jpeg2000: fix overflow in dequantization
Fixes decoding of file generated with:
ffmpeg -f lavfi -i smptehdbars=hd720 -pix_fmt rgb48 /tmp/o.jp2
Reviewed-by: Nicolas BERTRAND <nicoinattendu at gmail.com>
Signed-off-by: Michael Niedermayer <michaelni at gmx.at>
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=f57119b8e58cb5437c3ab40d797293ecb9b4a894
---
libavcodec/j2kenc.c | 4 ++--
libavcodec/jpeg2000.c | 2 +-
libavcodec/jpeg2000dec.c | 2 +-
3 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/libavcodec/j2kenc.c b/libavcodec/j2kenc.c
index 48c1db8..fa15aad 100644
--- a/libavcodec/j2kenc.c
+++ b/libavcodec/j2kenc.c
@@ -802,7 +802,7 @@ static void truncpasses(Jpeg2000EncoderContext *s, Jpeg2000Tile *tile)
Jpeg2000Cblk *cblk = prec->cblk + cblkno;
cblk->ninclpasses = getcut(cblk, s->lambda,
- (int64_t)dwt_norms[codsty->transform == FF_DWT53][bandpos][lev] * (int64_t)band->i_stepsize >> 16);
+ (int64_t)dwt_norms[codsty->transform == FF_DWT53][bandpos][lev] * (int64_t)band->i_stepsize >> 15);
}
}
}
@@ -863,7 +863,7 @@ static int encode_tile(Jpeg2000EncoderContext *s, Jpeg2000Tile *tile, int tileno
int *ptr = t1.data[y-yy0];
for (x = xx0; x < xx1; x++){
*ptr = (comp->i_data[(comp->coord[0][1] - comp->coord[0][0]) * y + x]);
- *ptr = (int64_t)*ptr * (int64_t)(16384 * 65536 / band->i_stepsize) >> 14 - NMSEDEC_FRACBITS;
+ *ptr = (int64_t)*ptr * (int64_t)(16384 * 65536 / band->i_stepsize) >> 15 - NMSEDEC_FRACBITS;
ptr++;
}
}
diff --git a/libavcodec/jpeg2000.c b/libavcodec/jpeg2000.c
index f044164..cb1a64d 100644
--- a/libavcodec/jpeg2000.c
+++ b/libavcodec/jpeg2000.c
@@ -320,7 +320,7 @@ int ff_jpeg2000_init_component(Jpeg2000Component *comp,
if (!av_codec_is_encoder(avctx->codec))
band->f_stepsize *= 0.5;
- band->i_stepsize = band->f_stepsize * (1 << 16);
+ band->i_stepsize = band->f_stepsize * (1 << 15);
/* computation of tbx_0, tbx_1, tby_0, tby_1
* see ISO/IEC 15444-1:2002 B.5 eq. B-15 and tbl B.1
diff --git a/libavcodec/jpeg2000dec.c b/libavcodec/jpeg2000dec.c
index e2a9a95..d9b9888 100644
--- a/libavcodec/jpeg2000dec.c
+++ b/libavcodec/jpeg2000dec.c
@@ -1024,7 +1024,7 @@ static void dequantization_int(int x, int y, Jpeg2000Cblk *cblk,
int32_t *datap = &comp->i_data[(comp->coord[0][1] - comp->coord[0][0]) * (y + j) + x];
int *src = t1->data[j];
for (i = 0; i < w; ++i)
- datap[i] = (src[i] * band->i_stepsize + (1 << 15)) >> 16;
+ datap[i] = (src[i] * band->i_stepsize + (1 << 14)) >> 15;
}
}
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