add tests

all done, I think

ChangeLog

@@ -10,7 +10,8 @@
 - all loaders have a @fail option, meaning fail on first warning, though it
   only does anything for jpg and csv
 - add vips_image_get_fields() to help bindings
-- add multi-page read to tiffload
+- add tiff multi-page read/write
+- add VIPS_META_PAGE_HEIGHT metadata
 
 11/11/16 started 8.4.4
 - fix crash in vips.exe arg parsing on Windows, thanks Yury

TODO

@@ -1,16 +1,12 @@
-- add VIPS_META_PAGE_HEIGHT and probably some others too .. "orientation"?
-
-- in wtiff_layer_rewind() we size strip height by tileh, but is this correct
-  for strip images?
-
-- test data
-
-	http://downloads.openmicroscopy.org/images/OME-TIFF/2016-06/bioformats-artificial/multi-channel-z-series.ome.tif
-
 - all toilet roll loaders need to set "page-height"
 
   magick, pdf and tiff need to use the same page/n interface
 
+
+
+
+
+
 - not sure about utf8 error messages on win
 
 - strange: 

libvips/foreign/tiff2vips.c

@@ -1209,7 +1209,8 @@ rtiff_set_header( Rtiff *rtiff, VipsImage *out )
 	out->Ysize = rtiff->header.height * rtiff->n;
 
 	if( rtiff->n > 1 ) 
-		vips_image_set_int( out, "page-height", rtiff->header.height );
+		vips_image_set_int( out, 
+			VIPS_META_PAGE_HEIGHT, rtiff->header.height );
 
 	/* Even though we could end up serving tiled data, always hint
 	 * THINSTRIP, since we're quite happy doing that too, and it could need

libvips/foreign/tiffload.c

@@ -328,8 +328,8 @@ vips_foreign_load_tiff_buffer_init( VipsForeignLoadTiffBuffer *buffer )
  *
  * @n means load this many pages. By default a single page is read. All the
  * pages must have the same dimensions, and they are loaded as a tall, thin
- * "toilet roll" image. The "page-height" metadata tag gives the height in
- * pixels of each page. Use -1 to load all pages. 
+ * "toilet roll" image. The #VIPS_META_PAGE_HEIGHT metadata 
+ * tag gives the height in pixels of each page. Use -1 to load all pages. 
  *
  * Setting @autorotate to %TRUE will make the loader interpret the 
  * orientation tag and automatically rotate the image appropriately during

libvips/foreign/tiffsave.c

@@ -475,6 +475,10 @@ vips_foreign_save_tiff_buffer_init( VipsForeignSaveTiffBuffer *buffer )
  *
  * Write a VIPS image to a file as TIFF.
  *
+ * If @in has the #VIPS_META_PAGE_HEIGHT metadata item, this is assumed to be a
+ * "toilet roll" image. It will be
+ * written as series of pages, each #VIPS_META_PAGE_HEIGHT pixels high. 
+ *
  * Use @compression to set the tiff compression. Currently jpeg, packbits,
  * fax4, lzw, none and deflate are supported. The default is no compression.
  * JPEG compression is a good lossy compressor for photographs, packbits is 

libvips/foreign/vips2tiff.c

@@ -198,9 +198,9 @@
  */
 
 /* 
- */
 #define DEBUG_VERBOSE
 #define DEBUG
+ */
 
 #ifdef HAVE_CONFIG_H
 #include <config.h>
@@ -921,8 +921,9 @@ wtiff_new( VipsImage *im, const char *filename,
 
 	/* Check for a toilet roll image.
 	 */
-	if( vips_image_get_typeof( im, "page-height" ) &&
-		vips_image_get_int( im, "page-height", &wtiff->page_height ) ) {
+	if( vips_image_get_typeof( im, VIPS_META_PAGE_HEIGHT ) &&
+		vips_image_get_int( im, 
+			VIPS_META_PAGE_HEIGHT, &wtiff->page_height ) ) {
 		wtiff_free( wtiff );
 		return( NULL );
 	}

libvips/include/vips/header.h

@@ -133,6 +133,15 @@ extern "C" {
  */
 #define VIPS_META_ORIENTATION "orientation"
 
+/**
+ * VIPS_META_PAGE_HEIGHT:
+ *
+ * If set, the height of each page when this image was loaded. If you save an
+ * image with "page-height" set to a format that supports multiple pages, such
+ * as tiff, the image will be saved as a series of pages. 
+ */
+#define VIPS_META_PAGE_HEIGHT "page-height"
+
 guint64 vips_format_sizeof( VipsBandFormat format );
 guint64 vips_format_sizeof_unsafe( VipsBandFormat format );
 

test/test_foreign.py

@@ -41,6 +41,7 @@ class TestForeign(unittest.TestCase):
         self.jpeg_file = "images/йцук.jpg"
         self.png_file = "images/sample.png"
         self.tiff_file = "images/sample.tif"
+        self.ome_file = "images/multi-channel-z-series.ome.tif"
         self.profile_file = "images/sRGB.icm"
         self.analyze_file = "images/t00740_tr1_segm.hdr"
         self.gif_file = "images/cramps.gif"
@@ -315,6 +316,39 @@ class TestForeign(unittest.TestCase):
         self.assertEqual(x1.height, x2.width)
         os.unlink("test-14.tif")
 
+        x = Vips.Image.new_from_file(self.ome_file)
+        self.assertEqual(x.width, 439)
+        self.assertEqual(x.height, 167)
+        page_height = x.height
+
+        x = Vips.Image.new_from_file(self.ome_file, n = -1)
+        self.assertEqual(x.width, 439)
+        self.assertEqual(x.height, page_height * 15)
+
+        x = Vips.Image.new_from_file(self.ome_file, page = 1, n = -1)
+        self.assertEqual(x.width, 439)
+        self.assertEqual(x.height, page_height * 14)
+
+        x = Vips.Image.new_from_file(self.ome_file, page = 1, n = 2)
+        self.assertEqual(x.width, 439)
+        self.assertEqual(x.height, page_height * 2)
+
+        x = Vips.Image.new_from_file(self.ome_file, n = -1)
+        self.assertEqual(x(0,166)[0], 96)
+        self.assertEqual(x(0,167)[0], 0)
+        self.assertEqual(x(0,168)[0], 1)
+
+        x.write_to_file("test-15.tif")
+
+        x = Vips.Image.new_from_file("test-15.tif", n = -1)
+        self.assertEqual(x.width, 439)
+        self.assertEqual(x.height, page_height * 15)
+        self.assertEqual(x(0,166)[0], 96)
+        self.assertEqual(x(0,167)[0], 0)
+        self.assertEqual(x(0,168)[0], 1)
+
+        os.unlink("test-15.tif")
+
     def test_magickload(self):
         x = Vips.type_find("VipsForeign", "magickload")
         if not x.is_instantiatable():