@@ -174,38 +174,46 @@ static int filter_slice(AVFilterContext *ctx, void *arg, int jobnr,

             dstlinesize *= -1;

         }

-        for (y = start; y < end; y++) {

-            switch (pixstep) {

-            case 1:

+        switch (pixstep) {

+        case 1:

+            for (y = start; y < end; y++, dst += dstlinesize)

                 for (x = 0; x < outw; x++)

                     dst[x] = src[x*srclinesize + y];

-                break;

-            case 2:

+            break;

+        case 2:

+            for (y = start; y < end; y++, dst += dstlinesize) {

                 for (x = 0; x < outw; x++)

                     *((uint16_t *)(dst + 2*x)) = *((uint16_t *)(src + x*srclinesize + y*2));

-                break;

-            case 3:

+            }

+            break;

+        case 3:

+            for (y = start; y < end; y++, dst += dstlinesize) {

                 for (x = 0; x < outw; x++) {

                     int32_t v = AV_RB24(src + x*srclinesize + y*3);

                     AV_WB24(dst + 3*x, v);

                 }

-                break;

-            case 4:

+            }

+            break;

+        case 4:

+            for (y = start; y < end; y++, dst += dstlinesize) {

                 for (x = 0; x < outw; x++)

                     *((uint32_t *)(dst + 4*x)) = *((uint32_t *)(src + x*srclinesize + y*4));

-                break;

-            case 6:

+            }

+            break;

+        case 6:

+            for (y = start; y < end; y++, dst += dstlinesize) {

                 for (x = 0; x < outw; x++) {

                     int64_t v = AV_RB48(src + x*srclinesize + y*6);

                     AV_WB48(dst + 6*x, v);

                 }

-                break;

-            case 8:

+            }

+            break;

+        case 8:

+            for (y = start; y < end; y++, dst += dstlinesize) {

                 for (x = 0; x < outw; x++)

                     *((uint64_t *)(dst + 8*x)) = *((uint64_t *)(src + x*srclinesize + y*8));

-                break;

             }

-            dst += dstlinesize;

+            break;

         }

     }