fix png save

TODO

@@ -9,9 +9,7 @@
 	`gdouble' is invalid or out of range for property `yres' of 
 	type `gdouble'
 
-- png save from nip2 often makes bad pngs?
-
-  and clicking on one of those bad pngs in the file browser will lock nip2
+- clicking on bad pngs in the file browser will lock nip2
 
   they don't seem to bother "header" though, strange
 
@@ -44,6 +42,13 @@
 
   total of about 0.5s user time difference
 
+  ... tile size difference!
+
+  try 
+
+  	time ./vips.py wtc_tiled_small.tif x.tif --vips-tile-width=512
+	--vips-tile-height=512
+
 
 
 

libvips/foreign/vipspng.c

@@ -513,13 +513,19 @@ typedef struct {
 } Write;
 
 static void
-write_destroy( VipsImage *out, Write *write )
+write_finish( Write *write )
 {
 	VIPS_FREEF( fclose, write->fp );
 	if( write->pPng )
 		png_destroy_write_struct( &write->pPng, &write->pInfo );
 }
 
+static void
+write_destroy( VipsImage *out, Write *write )
+{
+	write_finish( write ); 
+}
+
 static Write *
 write_new( VipsImage *in )
 {
@@ -690,6 +696,8 @@ vips__png_write( VipsImage *in, const char *filename,
 		return( -1 );
 	}
 
+	write_finish( write );
+
 	return( 0 );
 }