fix some a/an typos

Signed-off-by: Lou Logan <lou@lrcd.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/libswscale/swscale_internal.h b/libswscale/swscale_internal.h
index f0bab78ee7..450805a58b 100644
--- a/libswscale/swscale_internal.h
+++ b/libswscale/swscale_internal.h
@@ -960,7 +960,7 @@ typedef struct SwsPlane
 } SwsPlane;
 
 /**
- * Struct which defines a slice of an image to be scaled or a output for
+ * Struct which defines a slice of an image to be scaled or an output for
  * a scaled slice.
  * A slice can also be used as intermediate ring buffer for scaling steps.
  */