[FFmpeg-cvslog] avfilter/vf_v360: fix various artifacts with cubemaps

[Paul B Mahol]

ffmpeg | branch: master | Paul B Mahol <onemda at gmail.com> | Fri Sep 20 18:14:41 2019 +0200| [bc89434a0bec1b813bd21fff27abdd6c83936f1f] | committer: Paul B Mahol

avfilter/vf_v360: fix various artifacts with cubemaps

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=bc89434a0bec1b813bd21fff27abdd6c83936f1f
---

 libavfilter/vf_v360.c | 24 ++++++++++++------------
 1 file changed, 12 insertions(+), 12 deletions(-)

diff --git a/libavfilter/vf_v360.c b/libavfilter/vf_v360.c
index 6509a95916..0ec26e67bf 100644
--- a/libavfilter/vf_v360.c
+++ b/libavfilter/vf_v360.c
@@ -1073,8 +1073,8 @@ static void cube3x2_to_xyz(const V360Context *s,
     const int ewi = ceilf(ew * (u_face + 1)) - u_shift;
     const int ehi = ceilf(eh * (v_face + 1)) - v_shift;
 
-    const float uf = 2.f * (i - u_shift) / ewi - 1.f;
-    const float vf = 2.f * (j - v_shift) / ehi - 1.f;
+    const float uf = 2.f * (i - u_shift + 0.5f) / ewi - 1.f;
+    const float vf = 2.f * (j - v_shift + 0.5f) / ehi - 1.f;
 
     cube_to_xyz(s, uf, vf, face, vec);
 }
@@ -1114,8 +1114,8 @@ static void xyz_to_cube3x2(const V360Context *s,
     ewi = ceilf(ew * (u_face + 1)) - ceilf(ew * u_face);
     ehi = ceilf(eh * (v_face + 1)) - ceilf(eh * v_face);
 
-    uf = 0.5f * ewi * (uf + 1.f);
-    vf = 0.5f * ehi * (vf + 1.f);
+    uf = 0.5f * ewi * (uf + 1.f) - 0.5f;
+    vf = 0.5f * ehi * (vf + 1.f) - 0.5f;
 
     ui = floorf(uf);
     vi = floorf(vf);
@@ -1188,8 +1188,8 @@ static void cube1x6_to_xyz(const V360Context *s,
     const int v_shift = ceilf(eh * face);
     const int ehi = ceilf(eh * (face + 1)) - v_shift;
 
-    const float uf = 2.f *  i            / ew  - 1.f;
-    const float vf = 2.f * (j - v_shift) / ehi - 1.f;
+    const float uf = 2.f * (i           + 0.5f) / ew  - 1.f;
+    const float vf = 2.f * (j - v_shift + 0.5f) / ehi - 1.f;
 
     cube_to_xyz(s, uf, vf, face, vec);
 }
@@ -1216,8 +1216,8 @@ static void cube6x1_to_xyz(const V360Context *s,
     const int u_shift = ceilf(ew * face);
     const int ewi = ceilf(ew * (face + 1)) - u_shift;
 
-    const float uf = 2.f * (i - u_shift) / ewi - 1.f;
-    const float vf = 2.f *  j            / eh  - 1.f;
+    const float uf = 2.f * (i - u_shift + 0.5f) / ewi - 1.f;
+    const float vf = 2.f * (j           + 0.5f) / eh  - 1.f;
 
     cube_to_xyz(s, uf, vf, face, vec);
 }
@@ -1253,8 +1253,8 @@ static void xyz_to_cube1x6(const V360Context *s,
     face = s->in_cubemap_face_order[direction];
     ehi = ceilf(eh * (face + 1)) - ceilf(eh * face);
 
-    uf = 0.5f * ewi * (uf + 1.f);
-    vf = 0.5f * ehi * (vf + 1.f);
+    uf = 0.5f * ewi * (uf + 1.f) - 0.5f;
+    vf = 0.5f * ehi * (vf + 1.f) - 0.5f;
 
     ui = floorf(uf);
     vi = floorf(vf);
@@ -1329,8 +1329,8 @@ static void xyz_to_cube6x1(const V360Context *s,
     face = s->in_cubemap_face_order[direction];
     ewi = ceilf(ew * (face + 1)) - ceilf(ew * face);
 
-    uf = 0.5f * ewi * (uf + 1.f);
-    vf = 0.5f * ehi * (vf + 1.f);
+    uf = 0.5f * ewi * (uf + 1.f) - 0.5f;
+    vf = 0.5f * ehi * (vf + 1.f) - 0.5f;
 
     ui = floorf(uf);
     vi = floorf(vf);