@@ -761,12 +761,12 @@ static int configure_input_video_filter(FilterGraph *fg, InputFilter *ifilter,
theta = get_rotation(displaymatrix);
if (fabs(theta - 90) < 1.0) {
+ ret = insert_filter(&last_filter, &pad_idx, "transpose", "clock");
if (displaymatrix[3] > 0) {
ret = insert_filter(&last_filter, &pad_idx, "hflip", NULL);
if (ret < 0)
return ret;
}
- ret = insert_filter(&last_filter, &pad_idx, "transpose", "clock");
} else if (fabs(theta - 180) < 1.0) {
if (displaymatrix[0] < 0) {
ret = insert_filter(&last_filter, &pad_idx, "hflip", NULL);
@@ -777,12 +777,12 @@ static int configure_input_video_filter(FilterGraph *fg, InputFilter *ifilter,
ret = insert_filter(&last_filter, &pad_idx, "vflip", NULL);
}
} else if (fabs(theta - 270) < 1.0) {
+ ret = insert_filter(&last_filter, &pad_idx, "transpose", "cclock");
if (displaymatrix[3] < 0) {
ret = insert_filter(&last_filter, &pad_idx, "hflip", NULL);
if (ret < 0)
return ret;
}
- ret = insert_filter(&last_filter, &pad_idx, "transpose", "cclock");
} else if (fabs(theta) > 1.0) {
char rotate_buf[64];
snprintf(rotate_buf, sizeof(rotate_buf), "%f*PI/180", theta);
In case of an orthogonal transformation av_display_rotation_get() returns the (anticlockwise) degree that the unit vector in x-direction gets rotated by; get_rotation in cmdutils.c makes a clockwise degree out of this. So if one inserts a transpose filter corresponding to this degree, then the x-vector gets mapped correctly and there are two possibilities for image of the y-vector, namely the two unit vectors orthogonal to the image of the x-vector. E.g. if the x-vector gets rotated by 90° clockwise, then the two possibilities for the y-vector are the unit vector in x direction or its opposite. The latter case is a simple 90° rotation for both vectors* whereas the former is a simple 90° clockwise rotation followed by a horizontal flip. These two cases can be distinguished by looking at the x-coordinate of the image of the y-vector, i.e. by looking at displaymatrix[3]. Similarly for the case of a 270° clockwise rotation. These two cases were previously wrong (they were made to match wrongly parsed exif rotation tag values). *: For display matrices, the y-axis points downward. Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com> --- fftools/ffmpeg_filter.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)