From: Michael Niedermayer <michae...@gmx.at>
This should make this code more robust and simpler.
The use of hypot is by Ganesh Ajjanagadde.
Also use the context display matrix instead of the local one.
Signed-off-by: Vittorio Giovara <vittorio.giov...@gmail.com>
---
libavformat/mov.c | 22 ++++++++++------------
1 file changed, 10 insertions(+), 12 deletions(-)
diff --git a/libavformat/mov.c b/libavformat/mov.c
index 36e75d5..00ecdc7 100644
--- a/libavformat/mov.c
+++ b/libavformat/mov.c
@@ -2752,7 +2752,6 @@ static int mov_read_tkhd(MOVContext *c, AVIOContext *pb,
MOVAtom atom)
int i;
int width;
int height;
- int64_t disp_transform[2];
int display_matrix[3][3];
AVStream *st;
MOVStreamContext *sc;
@@ -2824,19 +2823,18 @@ static int mov_read_tkhd(MOVContext *c, AVIOContext
*pb, MOVAtom atom)
// transform the display width/height according to the matrix
// skip this when the display matrix is the identity one
- // to keep the same scale, use [width height 1<<16]
if (width && height && sc->display_matrix) {
+ double disp_transform[2];
+
for (i = 0; i < 2; i++)
- disp_transform[i] =
- (int64_t) width * display_matrix[0][i] +
- (int64_t) height * display_matrix[1][i] +
- ((int64_t) display_matrix[2][i] << 16);
-
- //sample aspect ratio is new width/height divided by old width/height
- if (disp_transform[0] > 0 && disp_transform[1] > 0)
- st->sample_aspect_ratio = av_d2q(
- ((double) disp_transform[0] * height) /
- ((double) disp_transform[1] * width), INT_MAX);
+ disp_transform[i] = hypot(display_matrix[i][0],
display_matrix[i][1]);
+
+ // only sane values allowed (no zeros or overflows)
+ if (disp_transform[0] > 0 && disp_transform[0] < (1 << 24) &&
+ disp_transform[1] > 0 && disp_transform[1] < (1 << 24) &&
+ fabs((disp_transform[0] / disp_transform[1]) - 1.0) > 0.01) {
+ st->sample_aspect_ratio = av_d2q(disp_transform[0] /
disp_transform[1], INT_MAX);
+ }
}
return 0;
}
--
2.10.0
_______________________________________________
libav-devel mailing list
libav-devel@libav.org
https://lists.libav.org/mailman/listinfo/libav-devel
