From: Bborie Park <bkpark at ucdavis.edu>
Date: Mon, 16 May 2011 19:54:11 +0000 (+0000)
Subject: Add ST_AsPNG
X-Git-Tag: 2.0.0alpha1~1653
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=19af7ff735cfa001eb16f3e62045993ee6392bdb;p=postgis

Add ST_AsPNG

	- added SQL functions for ST_AsPNG
	- added regression tests

Associated ticket is #342


git-svn-id: http://svn.osgeo.org/postgis/trunk@7158 b70326c6-7e19-0410-871a-916f4a2858ee
---

diff --git a/raster/rt_pg/rtpostgis.sql.in.c b/raster/rt_pg/rtpostgis.sql.in.c
index cb2c8cbad..4b3b0158d 100644
--- a/raster/rt_pg/rtpostgis.sql.in.c
+++ b/raster/rt_pg/rtpostgis.sql.in.c
@@ -1328,6 +1328,93 @@ CREATE OR REPLACE FUNCTION st_asjpeg(rast raster, nband int, quality int)
 	AS $$ SELECT st_asjpeg($1, ARRAY[$2], $3) $$
 	LANGUAGE 'SQL' IMMUTABLE STRICT;
 
+-----------------------------------------------------------------------
+-- ST_AsPNG
+-----------------------------------------------------------------------
+-- Cannot be strict as "options" can be NULL
+CREATE OR REPLACE FUNCTION st_aspng(rast raster, options text[])
+	RETURNS bytea
+	AS $$
+	DECLARE
+		num_bands int;
+		i int;
+		pt text;
+	BEGIN
+		num_bands := st_numbands($1);
+
+		-- PNG only allows 1 or 3 bands
+		IF num_bands > 3 THEN
+			RAISE NOTICE 'The PNG format only permits one or three bands.  The first three bands will be used.';
+			rast := st_band(rast, ARRAY[1, 2, 3]);
+			num_bands := st_numbands(rast);
+		ELSEIF num_bands > 1 THEN
+			RAISE NOTICE 'The PNG format only permits one or three bands.  The first band will be used.';
+			rast := st_band(rast, ARRAY[1]);
+			num_bands := st_numbands(rast);
+		END IF;
+
+		-- PNG only supports 8BUI and 16BUI pixeltype
+		FOR i IN 1..num_bands LOOP
+			pt = st_bandpixeltype(rast, i);
+			IF pt != '8BUI' AND pt != '16BUI' THEN
+				RAISE EXCEPTION 'The pixel type of band % in the raster is not 8BUI or 16BUI.  The PNG format can only be used with 8BUI and 16BUI pixel types.', i;
+			END IF;
+		END LOOP;
+
+		RETURN st_asgdalraster($1, 'PNG', $2, NULL);
+	END;
+	$$ LANGUAGE 'plpgsql' IMMUTABLE;
+
+CREATE OR REPLACE FUNCTION st_aspng(rast raster)
+	RETURNS bytea
+	AS $$ SELECT st_aspng($1, NULL::text[]) $$
+	LANGUAGE 'SQL' IMMUTABLE STRICT;
+
+CREATE OR REPLACE FUNCTION st_aspng(rast raster, nbands int[], options text[])
+	RETURNS bytea
+	AS $$ SELECT st_aspng(st_band($1, $2), $3) $$
+	LANGUAGE 'SQL' IMMUTABLE STRICT;
+
+CREATE OR REPLACE FUNCTION st_aspng(rast raster, nbands int[])
+	RETURNS bytea
+	AS $$ SELECT st_aspng(st_band($1, $2), NULL::text[]) $$
+	LANGUAGE 'SQL' IMMUTABLE STRICT;
+
+CREATE OR REPLACE FUNCTION st_aspng(rast raster, nband int)
+	RETURNS bytea
+	AS $$ SELECT st_aspng(st_band($1, $2)) $$
+	LANGUAGE 'SQL' IMMUTABLE STRICT;
+
+CREATE OR REPLACE FUNCTION st_aspng(rast raster, nbands int[], compression int)
+	RETURNS bytea
+	AS $$
+	DECLARE
+		options text[];
+	BEGIN
+		IF compression IS NOT NULL THEN
+			IF compression > 9 THEN
+				compression := 9;
+			ELSEIF compression < 1 THEN
+				compression := 1;
+			END IF;
+
+			options := array_append(options, 'ZLEVEL=' || compression);
+		END IF;
+
+		RETURN st_aspng(st_band($1, $2), options);
+	END;
+	$$ LANGUAGE 'plpgsql' IMMUTABLE STRICT;
+
+CREATE OR REPLACE FUNCTION st_aspng(rast raster, nband int, options text[])
+	RETURNS bytea
+	AS $$ SELECT st_aspng(st_band($1, $2), $3) $$
+	LANGUAGE 'SQL' IMMUTABLE STRICT;
+
+CREATE OR REPLACE FUNCTION st_aspng(rast raster, nband int, compression int)
+	RETURNS bytea
+	AS $$ SELECT st_aspng($1, ARRAY[$2], $3) $$
+	LANGUAGE 'SQL' IMMUTABLE STRICT;
+
 -----------------------------------------------------------------------
 -- MapAlgebra
 -----------------------------------------------------------------------
diff --git a/raster/test/regress/Makefile.in b/raster/test/regress/Makefile.in
index 0a972b26c..b7eae7402 100644
--- a/raster/test/regress/Makefile.in
+++ b/raster/test/regress/Makefile.in
@@ -45,6 +45,7 @@ TEST_FUNC = \
 	rt_asgdalraster.sql \
 	rt_astiff.sql \
 	rt_asjpeg.sql \
+	rt_aspng.sql \
 	$(NULL)
 
 TEST_PROPS = \
diff --git a/raster/test/regress/rt_aspng.sql b/raster/test/regress/rt_aspng.sql
new file mode 100644
index 000000000..898c410e5
--- /dev/null
+++ b/raster/test/regress/rt_aspng.sql
@@ -0,0 +1,94 @@
+SELECT md5(
+	ST_AsPNG(
+		ST_AddBand(ST_MakeEmptyRaster(200, 200, 10, 10, 2, 2, 0, 0, -1), 1, '8BSI', 123, NULL)
+	)
+);
+SELECT md5(
+	ST_AsPNG(
+		ST_AddBand(ST_MakeEmptyRaster(200, 200, 10, 10, 2, 2, 0, 0, -1), 1, '8BUI', 123, NULL)
+	)
+);
+SELECT md5(
+	ST_AsPNG(
+		ST_AddBand(ST_MakeEmptyRaster(200, 200, 10, 10, 2, 2, 0, 0, -1), 1, '8BSI', -123, NULL)
+	)
+);
+SELECT md5(
+	ST_AsPNG(
+		ST_AddBand(ST_MakeEmptyRaster(200, 200, 10, 10, 2, 2, 0, 0, -1), 1, '8BUI', 254, NULL)
+	)
+);
+SELECT md5(
+	ST_AsPNG(
+		ST_AddBand(
+			ST_AddBand(
+				ST_AddBand(
+					ST_MakeEmptyRaster(200, 200, 10, 10, 2, 2, 0, 0, -1)
+					, 1, '8BSI', 1, -1
+				)
+				, 2, '8BSI', 11, -1
+			)
+			, 3, '8BSI', 111, -1
+		),
+		ARRAY['ZLEVEL=1']
+	)
+);
+SELECT md5(
+	ST_AsPNG(
+		ST_AddBand(
+			ST_AddBand(
+				ST_AddBand(
+					ST_MakeEmptyRaster(200, 200, 10, 10, 2, 2, 0, 0, -1)
+					, 1, '8BSI', 1, -1
+				)
+				, 2, '8BSI', 11, -1
+			)
+			, 3, '8BSI', 111, -1
+		),
+		ARRAY['ZLEVEL=9']
+	)
+);
+SELECT md5(
+	ST_AsPNG(
+		ST_AddBand(
+			ST_AddBand(
+				ST_AddBand(
+					ST_MakeEmptyRaster(200, 200, 10, 10, 2, 2, 0, 0, -1)
+					, 1, '8BSI', 1, 1
+				)
+				, 2, '8BSI', 11, 1
+			)
+			, 3, '8BSI', 111, 1
+		),
+		ARRAY['ZLEVEL=9']
+	)
+);
+SELECT md5(
+	ST_AsPNG(
+		ST_AddBand(
+			ST_AddBand(
+				ST_MakeEmptyRaster(200, 200, 10, 10, 2, 2, 0, 0, -1)
+				, 1, '8BUI', 1, 1
+			)
+			, 2, '8BUI', 11, 1
+		),
+		ARRAY[1],
+		6
+	)
+);
+SELECT md5(
+	ST_AsPNG(
+		ST_AddBand(
+			ST_AddBand(
+				ST_AddBand(
+					ST_MakeEmptyRaster(200, 200, 10, 10, 2, 2, 0, 0, -1)
+					, 1, '8BUI', 1, 1
+				)
+				, 2, '8BUI', 11, 1
+			)
+			, 3, '8BUI', 111, 1
+		),
+		ARRAY[3,1],
+		6
+	)
+);
diff --git a/raster/test/regress/rt_aspng_expected b/raster/test/regress/rt_aspng_expected
new file mode 100644
index 000000000..460bb9d7d
--- /dev/null
+++ b/raster/test/regress/rt_aspng_expected
@@ -0,0 +1,13 @@
+ERROR:  The pixel type of band 1 in the raster is not 8BUI or 16BUI.  The PNG format can only be used with 8BUI and 16BUI pixel types.
+55279950e29968bcf36b2c11ce8bf88b
+ERROR:  The pixel type of band 1 in the raster is not 8BUI or 16BUI.  The PNG format can only be used with 8BUI and 16BUI pixel types.
+24188762b5745acda4aa7b92776e7280
+NOTICE:  The PNG format only permits one or three bands.  The first band will be used.
+ERROR:  The pixel type of band 1 in the raster is not 8BUI or 16BUI.  The PNG format can only be used with 8BUI and 16BUI pixel types.
+NOTICE:  The PNG format only permits one or three bands.  The first band will be used.
+ERROR:  The pixel type of band 1 in the raster is not 8BUI or 16BUI.  The PNG format can only be used with 8BUI and 16BUI pixel types.
+NOTICE:  The PNG format only permits one or three bands.  The first band will be used.
+ERROR:  The pixel type of band 1 in the raster is not 8BUI or 16BUI.  The PNG format can only be used with 8BUI and 16BUI pixel types.
+dfff54767aad7aa842f45e5b83326f0b
+NOTICE:  The PNG format only permits one or three bands.  The first band will be used.
+58168aa11f7ccdf095e5ed02bde1e676