ffmpeg | branch: master | Paul B Mahol <onemda@gmail.com> | Sat Feb 29 14:22:51 2020 +0100| [2dfd9445ff9b69a2b826e7b4c21c316689000147] | committer: Paul B Mahol avfilter/vf_v360: improve tetrahedron input format at frame borders

http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=2dfd9445ff9b69a2b8...

libavfilter/vf_v360.c | 37 +++++++++++++++++++++++++++++++++++-- 1 file changed, 35 insertions(+), 2 deletions(-) diff --git a/libavfilter/vf_v360.c b/libavfilter/vf_v360.c index 1cdbaf7330..90e45b4fd0 100644 --- a/libavfilter/vf_v360.c +++ b/libavfilter/vf_v360.c @@ -622,6 +622,39 @@ static inline int mod(int a, int b) } } +/** + * Reflect y operation. + * + * @param y input vertical position + * @param h input height + */ +static inline int reflecty(int y, int h) +{ + if (y < 0) { + return -y; + } else if (y >= h) { + return 2 * h - 1 - y; + } + + return y; +} + +/** + * Reflect x operation. + * + * @param x input horizontal position + * @param y input vertical position + * @param w input width + * @param h input height + */ +static inline int reflectx(int x, int y, int w, int h) +{ + if (y < 0 || y >= h) + return w - 1 - x; + + return mod(x, w); +} + /** * Convert char to corresponding direction. * Used for cubemap options. @@ -2746,8 +2779,8 @@ static int xyz_to_tetrahedron(const V360Context *s, for (int i = 0; i < 4; i++) { for (int j = 0; j < 4; j++) { - us[i][j] = mod(ui + j - 1, width); - vs[i][j] = av_clip(vi + i - 1, 0, height - 1); + us[i][j] = reflectx(ui + j - 1, vi + i - 1, width, height); + vs[i][j] = reflecty(vi + i - 1, height); } }