diff --git a/scripts/pnglibconf.dfa b/scripts/pnglibconf.dfa
index ffde44bc9..776ae923b 100644
--- a/scripts/pnglibconf.dfa
+++ b/scripts/pnglibconf.dfa
@@ -264,7 +264,12 @@ setting USER_CHUNK_MALLOC_MAX default 0
 # See the comments above about how to change options and settings.
 
 # READ options
+
+option READ_16BIT requires READ enables 16BIT
+option NO_READ_16BIT requires READ_16_TO_8
+
 option READ enables READ_INTERLACING
+
 option READ_QUANTIZE requires READ
 
 option READ_TRANSFORMS requires READ
@@ -314,7 +319,7 @@ option READ_16_TO_8_ACCURATE_SCALE requires READ disabled
 # WRITE options
 option WRITE
 
-option WRITE_16BIT requires WRITE
+option WRITE_16BIT requires WRITE enables 16BIT
 
 option WRITE_TRANSFORMS requires WRITE
 = NO_WRITE_TRANSFORMS PNG_WRITE_TRANSFORMS_NOT_SUPPORTED
@@ -341,7 +346,7 @@ option WRITE_WEIGHTED_FILTER requires WRITE
 
 option WRITE_FLUSH requires WRITE
 
-# Note: this can be turned off explicitly, is this correcct?
+# Note: this can be turned off explicitly, is this correct?
 option USER_TRANSFORM_PTR if READ_USER_TRANSFORM WRITE_USER_TRANSFORM
 
 # Any chunks you are not interested in, you can undef here.  The