[FFmpeg-devel] [PATCH 2/2] lavfi/lut: simplify nested lut plane stepping.

[Clément Bœsch]

---
 libavfilter/vf_lut.c | 14 +++++---------
 1 file changed, 5 insertions(+), 9 deletions(-)

diff --git a/libavfilter/vf_lut.c b/libavfilter/vf_lut.c
index be497ac..21309a5 100644
--- a/libavfilter/vf_lut.c
+++ b/libavfilter/vf_lut.c
@@ -286,15 +286,11 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *in)
             inrow  = inrow0;
             outrow = outrow0;
             for (j = 0; j < w; j++) {
-                outrow[0] = tab[0][inrow[0]];
-                if (lut->step>1) {
-                    outrow[1] = tab[1][inrow[1]];
-                    if (lut->step>2) {
-                        outrow[2] = tab[2][inrow[2]];
-                        if (lut->step>3) {
-                            outrow[3] = tab[3][inrow[3]];
-                        }
-                    }
+                switch (lut->step) {
+                case 3:  outrow[3] = tab[3][inrow[3]]; // Fall-through
+                case 2:  outrow[2] = tab[2][inrow[2]]; // Fall-through
+                case 1:  outrow[1] = tab[1][inrow[1]]; // Fall-through
+                default: outrow[0] = tab[0][inrow[0]];
                 }
                 outrow += lut->step;
                 inrow  += lut->step;
-- 
1.8.2.1