diff --git a/ChangeLog b/ChangeLog
index 588672ed..75cf5fbe 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -14,6 +14,8 @@
 - added vips_mapim() ... resample with an index image, plus test
 - try to improve vips_resize() quality a little more
 - vips_resize() can do non-square resizes
+- dzsave removes tile metadata by default, thanks Benjamin
+- added vips_image_new_from_memory_copy()
 
 7/5/15 started 8.1.1
 - oop, vips-8.0 wrapper script should be vips-8.1, thanks Danilo
diff --git a/doc/gtk-doc.make b/doc/gtk-doc.make
index e7916563..9ccd0b04 100644
--- a/doc/gtk-doc.make
+++ b/doc/gtk-doc.make
@@ -25,6 +25,7 @@ TARGET_DIR=$(HTML_DIR)/$(DOC_MODULE)
 
 SETUP_FILES = \
 	$(content_files)		\
+	$(expand_content_files)		\
 	$(DOC_MAIN_SGML_FILE)		\
 	$(DOC_MODULE)-sections.txt	\
 	$(DOC_MODULE)-overrides.txt
@@ -86,7 +87,7 @@ GTK_DOC_V_SETUP_0=@echo "  DOC   Preparing build";
 
 setup-build.stamp:
 	-$(GTK_DOC_V_SETUP)if test "$(abs_srcdir)" != "$(abs_builddir)" ; then \
-	    files=`echo $(SETUP_FILES) $(expand_content_files) $(DOC_MODULE).types`; \
+	    files=`echo $(SETUP_FILES) $(DOC_MODULE).types`; \
 	    if test "x$$files" != "x" ; then \
 	        for file in $$files ; do \
 	            destdir=`dirname $(abs_builddir)/$$file`; \
@@ -118,7 +119,7 @@ scan-build.stamp: setup-build.stamp $(HFILE_GLOB) $(CFILE_GLOB)
 	$(GTK_DOC_V_INTROSPECT)if grep -l '^..*$$' $(DOC_MODULE).types > /dev/null 2>&1 ; then \
 	    scanobj_options=""; \
 	    gtkdoc-scangobj 2>&1 --help | grep  >/dev/null "\-\-verbose"; \
-	    if test "$(?)" = "0"; then \
+	    if test "$$?" = "0"; then \
 	        if test "x$(V)" = "x1"; then \
 	            scanobj_options="--verbose"; \
 	        fi; \
@@ -162,17 +163,17 @@ GTK_DOC_V_XREF=$(GTK_DOC_V_XREF_$(V))
 GTK_DOC_V_XREF_=$(GTK_DOC_V_XREF_$(AM_DEFAULT_VERBOSITY))
 GTK_DOC_V_XREF_0=@echo "  DOC   Fixing cross-references";
 
-html-build.stamp: sgml.stamp $(DOC_MAIN_SGML_FILE) $(content_files)
+html-build.stamp: sgml.stamp $(DOC_MAIN_SGML_FILE) $(content_files) $(expand_content_files)
 	$(GTK_DOC_V_HTML)rm -rf html && mkdir html && \
 	mkhtml_options=""; \
 	gtkdoc-mkhtml 2>&1 --help | grep  >/dev/null "\-\-verbose"; \
-	if test "$(?)" = "0"; then \
+	if test "$$?" = "0"; then \
 	  if test "x$(V)" = "x1"; then \
 	    mkhtml_options="$$mkhtml_options --verbose"; \
 	  fi; \
 	fi; \
 	gtkdoc-mkhtml 2>&1 --help | grep  >/dev/null "\-\-path"; \
-	if test "$(?)" = "0"; then \
+	if test "$$?" = "0"; then \
 	  mkhtml_options="$$mkhtml_options --path=\"$(abs_srcdir)\""; \
 	fi; \
 	cd html && gtkdoc-mkhtml $$mkhtml_options $(MKHTML_OPTIONS) $(DOC_MODULE) ../$(DOC_MAIN_SGML_FILE)
@@ -194,11 +195,11 @@ GTK_DOC_V_PDF=$(GTK_DOC_V_PDF_$(V))
 GTK_DOC_V_PDF_=$(GTK_DOC_V_PDF_$(AM_DEFAULT_VERBOSITY))
 GTK_DOC_V_PDF_0=@echo "  DOC   Building PDF";
 
-pdf-build.stamp: sgml.stamp $(DOC_MAIN_SGML_FILE) $(content_files)
+pdf-build.stamp: sgml.stamp $(DOC_MAIN_SGML_FILE) $(content_files) $(expand_content_files)
 	$(GTK_DOC_V_PDF)rm -f $(DOC_MODULE).pdf && \
 	mkpdf_options=""; \
 	gtkdoc-mkpdf 2>&1 --help | grep  >/dev/null "\-\-verbose"; \
-	if test "$(?)" = "0"; then \
+	if test "$$?" = "0"; then \
 	  if test "x$(V)" = "x1"; then \
 	    mkpdf_options="$$mkpdf_options --verbose"; \
 	  fi; \
@@ -223,12 +224,15 @@ clean-local:
 	@if echo $(SCAN_OPTIONS) | grep -q "\-\-rebuild-types" ; then \
 	  rm -f $(DOC_MODULE).types; \
 	fi
+	@if echo $(SCAN_OPTIONS) | grep -q "\-\-rebuild-sections" ; then \
+	  rm -f $(DOC_MODULE)-sections.txt; \
+	fi
 
 distclean-local:
 	@rm -rf xml html $(REPORT_FILES) $(DOC_MODULE).pdf \
 	    $(DOC_MODULE)-decl-list.txt $(DOC_MODULE)-decl.txt
 	@if test "$(abs_srcdir)" != "$(abs_builddir)" ; then \
-	    rm -f $(SETUP_FILES) $(expand_content_files) $(DOC_MODULE).types; \
+	    rm -f $(SETUP_FILES) $(DOC_MODULE).types; \
 	fi
 
 maintainer-clean-local:
diff --git a/libvips/arithmetic/max.c b/libvips/arithmetic/max.c
index c40a2f1b..c189384ae 100644
--- a/libvips/arithmetic/max.c
+++ b/libvips/arithmetic/max.c
@@ -434,14 +434,14 @@ vips_max_class_init( VipsMaxClass *class )
 		_( "Horizontal position of maximum" ),
 		VIPS_ARGUMENT_OPTIONAL_OUTPUT,
 		G_STRUCT_OFFSET( VipsMax, x ),
-		0, 1000000, 0 );
+		0, VIPS_MAX_COORD, 0 );
 
 	VIPS_ARG_INT( class, "y", 3, 
 		_( "y" ), 
 		_( "Vertical position of maximum" ),
 		VIPS_ARGUMENT_OPTIONAL_OUTPUT,
 		G_STRUCT_OFFSET( VipsMax, y ),
-		0, 1000000, 0 );
+		0, VIPS_MAX_COORD, 0 );
 
 	VIPS_ARG_INT( class, "size", 4, 
 		_( "Size" ), 
diff --git a/libvips/arithmetic/min.c b/libvips/arithmetic/min.c
index cde84cae..6cadf068 100644
--- a/libvips/arithmetic/min.c
+++ b/libvips/arithmetic/min.c
@@ -437,14 +437,14 @@ vips_min_class_init( VipsMinClass *class )
 		_( "Horizontal position of minimum" ),
 		VIPS_ARGUMENT_OPTIONAL_OUTPUT,
 		G_STRUCT_OFFSET( VipsMin, x ),
-		0, 1000000, 0 );
+		0, VIPS_MAX_COORD, 0 );
 
 	VIPS_ARG_INT( class, "y", 3, 
 		_( "y" ), 
 		_( "Vertical position of minimum" ),
 		VIPS_ARGUMENT_OPTIONAL_OUTPUT,
 		G_STRUCT_OFFSET( VipsMin, y ),
-		0, 1000000, 0 );
+		0, VIPS_MAX_COORD, 0 );
 
 	VIPS_ARG_INT( class, "size", 4, 
 		_( "Size" ), 
diff --git a/libvips/conversion/copy.c b/libvips/conversion/copy.c
index 4a45dea9..b02359bc 100644
--- a/libvips/conversion/copy.c
+++ b/libvips/conversion/copy.c
@@ -285,21 +285,21 @@ vips_copy_class_init( VipsCopyClass *class )
 		_( "Image width in pixels" ),
 		VIPS_ARGUMENT_OPTIONAL_INPUT,
 		G_STRUCT_OFFSET( VipsCopy, width ),
-		0, 1000000, 0 );
+		0, VIPS_MAX_COORD, 0 );
 
 	VIPS_ARG_INT( class, "height", 4, 
 		_( "Height" ), 
 		_( "Image height in pixels" ),
 		VIPS_ARGUMENT_OPTIONAL_INPUT,
 		G_STRUCT_OFFSET( VipsCopy, height ),
-		0, 1000000, 0 );
+		0, VIPS_MAX_COORD, 0 );
 
 	VIPS_ARG_INT( class, "bands", 5, 
 		_( "Bands" ), 
 		_( "Number of bands in image" ),
 		VIPS_ARGUMENT_OPTIONAL_INPUT,
 		G_STRUCT_OFFSET( VipsCopy, bands ),
-		0, 1000000, 0 );
+		0, VIPS_MAX_COORD, 0 );
 
 	VIPS_ARG_ENUM( class, "format", 6, 
 		_( "Format" ), 
@@ -341,14 +341,14 @@ vips_copy_class_init( VipsCopyClass *class )
 		_( "Horizontal offset of origin" ),
 		VIPS_ARGUMENT_OPTIONAL_INPUT,
 		G_STRUCT_OFFSET( VipsCopy, xoffset ),
-		-1000000, 1000000, 0 );
+		-VIPS_MAX_COORD, VIPS_MAX_COORD, 0 );
 
 	VIPS_ARG_INT( class, "yoffset", 12, 
 		_( "Yoffset" ), 
 		_( "Vertical offset of origin" ),
 		VIPS_ARGUMENT_OPTIONAL_INPUT,
 		G_STRUCT_OFFSET( VipsCopy, yoffset ),
-		-1000000, 1000000, 0 );
+		-VIPS_MAX_COORD, VIPS_MAX_COORD, 0 );
 }
 
 static void
diff --git a/libvips/conversion/wrap.c b/libvips/conversion/wrap.c
index c85ed6c6..7c02f208 100644
--- a/libvips/conversion/wrap.c
+++ b/libvips/conversion/wrap.c
@@ -126,14 +126,14 @@ vips_wrap_class_init( VipsWrapClass *class )
 		_( "Left edge of input in output" ),
 		VIPS_ARGUMENT_OPTIONAL_INPUT,
 		G_STRUCT_OFFSET( VipsWrap, x ),
-		-1000000, 1000000, 0 );
+		-VIPS_MAX_COORD, VIPS_MAX_COORD, 0 );
 
 	VIPS_ARG_INT( class, "y", 4, 
 		_( "y" ), 
 		_( "Top edge of input in output" ),
 		VIPS_ARGUMENT_OPTIONAL_INPUT,
 		G_STRUCT_OFFSET( VipsWrap, y ),
-		-1000000, 1000000, 0 );
+		-VIPS_MAX_COORD, VIPS_MAX_COORD, 0 );
 
 }
 
diff --git a/libvips/create/black.c b/libvips/create/black.c
index 83ac451c..dfa2ede2 100644
--- a/libvips/create/black.c
+++ b/libvips/create/black.c
@@ -130,21 +130,21 @@ vips_black_class_init( VipsBlackClass *class )
 		_( "Image width in pixels" ),
 		VIPS_ARGUMENT_REQUIRED_INPUT,
 		G_STRUCT_OFFSET( VipsBlack, width ),
-		1, 1000000, 1 );
+		1, VIPS_MAX_COORD, 1 );
 
 	VIPS_ARG_INT( class, "height", 5, 
 		_( "Height" ), 
 		_( "Image height in pixels" ),
 		VIPS_ARGUMENT_REQUIRED_INPUT,
 		G_STRUCT_OFFSET( VipsBlack, height ),
-		1, 1000000, 1 );
+		1, VIPS_MAX_COORD, 1 );
 
 	VIPS_ARG_INT( class, "bands", 6, 
 		_( "Bands" ), 
 		_( "Number of bands in image" ),
 		VIPS_ARGUMENT_OPTIONAL_INPUT,
 		G_STRUCT_OFFSET( VipsBlack, bands ),
-		1, 1000000, 1 );
+		1, VIPS_MAX_COORD, 1 );
 }
 
 static void
diff --git a/libvips/create/fractsurf.c b/libvips/create/fractsurf.c
index 6d571176..e6c07ef8 100644
--- a/libvips/create/fractsurf.c
+++ b/libvips/create/fractsurf.c
@@ -103,14 +103,14 @@ vips_fractsurf_class_init( VipsFractsurfClass *class )
 		_( "Image width in pixels" ),
 		VIPS_ARGUMENT_REQUIRED_INPUT,
 		G_STRUCT_OFFSET( VipsFractsurf, width ),
-		1, 1000000, 64 );
+		1, VIPS_MAX_COORD, 64 );
 
 	VIPS_ARG_INT( class, "height", 5, 
 		_( "Height" ), 
 		_( "Image height in pixels" ),
 		VIPS_ARGUMENT_REQUIRED_INPUT,
 		G_STRUCT_OFFSET( VipsFractsurf, height ),
-		1, 1000000, 64 );
+		1, VIPS_MAX_COORD, 64 );
 
 	VIPS_ARG_DOUBLE( class, "fractal_dimension", 8, 
 		_( "Fractal dimension" ), 
diff --git a/libvips/create/gaussnoise.c b/libvips/create/gaussnoise.c
index 09145a68..5fee656e 100644
--- a/libvips/create/gaussnoise.c
+++ b/libvips/create/gaussnoise.c
@@ -154,14 +154,14 @@ vips_gaussnoise_class_init( VipsGaussnoiseClass *class )
 		_( "Image width in pixels" ),
 		VIPS_ARGUMENT_REQUIRED_INPUT,
 		G_STRUCT_OFFSET( VipsGaussnoise, width ),
-		1, 1000000, 1 );
+		1, VIPS_MAX_COORD, 1 );
 
 	VIPS_ARG_INT( class, "height", 5, 
 		_( "Height" ), 
 		_( "Image height in pixels" ),
 		VIPS_ARGUMENT_REQUIRED_INPUT,
 		G_STRUCT_OFFSET( VipsGaussnoise, height ),
-		1, 1000000, 1 );
+		1, VIPS_MAX_COORD, 1 );
 
 	VIPS_ARG_DOUBLE( class, "mean", 6, 
 		_( "Mean" ), 
diff --git a/libvips/create/point.c b/libvips/create/point.c
index 5eff84ac..06e14229 100644
--- a/libvips/create/point.c
+++ b/libvips/create/point.c
@@ -144,14 +144,14 @@ vips_point_class_init( VipsPointClass *class )
 		_( "Image width in pixels" ),
 		VIPS_ARGUMENT_REQUIRED_INPUT,
 		G_STRUCT_OFFSET( VipsPoint, width ),
-		1, 1000000, 1 );
+		1, VIPS_MAX_COORD, 1 );
 
 	VIPS_ARG_INT( class, "height", 3, 
 		_( "Height" ), 
 		_( "Image height in pixels" ),
 		VIPS_ARGUMENT_REQUIRED_INPUT,
 		G_STRUCT_OFFSET( VipsPoint, height ),
-		1, 1000000, 1 );
+		1, VIPS_MAX_COORD, 1 );
 
 	VIPS_ARG_BOOL( class, "uchar", 4, 
 		_( "Uchar" ), 
diff --git a/libvips/create/text.c b/libvips/create/text.c
index 01262927..f7ea3122 100644
--- a/libvips/create/text.c
+++ b/libvips/create/text.c
@@ -298,7 +298,7 @@ vips_text_class_init( VipsTextClass *class )
 		_( "Maximum image width in pixels" ),
 		VIPS_ARGUMENT_OPTIONAL_INPUT,
 		G_STRUCT_OFFSET( VipsText, width ),
-		0, 1000000, 0 );
+		0, VIPS_MAX_COORD, 0 );
 
 	VIPS_ARG_ENUM( class, "align", 7, 
 		_( "Align" ), 
diff --git a/libvips/create/xyz.c b/libvips/create/xyz.c
index d4a9940e..852de729 100644
--- a/libvips/create/xyz.c
+++ b/libvips/create/xyz.c
@@ -194,35 +194,35 @@ vips_xyz_class_init( VipsXyzClass *class )
 		_( "Image width in pixels" ),
 		VIPS_ARGUMENT_REQUIRED_INPUT,
 		G_STRUCT_OFFSET( VipsXyz, width ),
-		1, 1000000, 64 );
+		1, VIPS_MAX_COORD, 64 );
 
 	VIPS_ARG_INT( class, "height", 5, 
 		_( "Height" ), 
 		_( "Image height in pixels" ),
 		VIPS_ARGUMENT_REQUIRED_INPUT,
 		G_STRUCT_OFFSET( VipsXyz, height ),
-		1, 1000000, 64 );
+		1, VIPS_MAX_COORD, 64 );
 
 	VIPS_ARG_INT( class, "csize", 6, 
 		_( "csize" ), 
 		_( "Size of third dimension" ),
 		VIPS_ARGUMENT_OPTIONAL_INPUT,
 		G_STRUCT_OFFSET( VipsXyz, csize ),
-		1, 1000000, 1 );
+		1, VIPS_MAX_COORD, 1 );
 
 	VIPS_ARG_INT( class, "dsize", 7, 
 		_( "dsize" ), 
 		_( "Size of fourth dimension" ),
 		VIPS_ARGUMENT_OPTIONAL_INPUT,
 		G_STRUCT_OFFSET( VipsXyz, dsize ),
-		1, 1000000, 1 );
+		1, VIPS_MAX_COORD, 1 );
 
 	VIPS_ARG_INT( class, "esize", 8, 
 		_( "esize" ), 
 		_( "Size of fifth dimension" ),
 		VIPS_ARGUMENT_OPTIONAL_INPUT,
 		G_STRUCT_OFFSET( VipsXyz, esize ),
-		1, 1000000, 1 );
+		1, VIPS_MAX_COORD, 1 );
 
 }
 
diff --git a/libvips/foreign/dzsave.c b/libvips/foreign/dzsave.c
index cee9bda7..aac907e4 100644
--- a/libvips/foreign/dzsave.c
+++ b/libvips/foreign/dzsave.c
@@ -55,6 +55,8 @@
  * 	- allow zip > 4gb if we have a recent libgsf
  * 9/9/15
  * 	- better overlap handling, thanks robclouth 
+ * 25/11/15
+ * 	- always strip tile metadata 
  */
 
 /*
@@ -1141,8 +1143,12 @@ strip_work( VipsThreadState *state, void *a )
 		x = t;
 	}
 
+	/* Hopefully no one will want the same metadata on all the tiles.
+	 */
 	vips_image_set_int( x, "hide-progress", 1 );
-	if( vips_image_write_to_buffer( x, dz->suffix, &buf, &len, NULL ) ) {
+	if( vips_image_write_to_buffer( x, dz->suffix, &buf, &len, 
+		"strip", TRUE, 
+		NULL ) ) {
 		g_object_unref( x );
 		return( -1 );
 	}
diff --git a/libvips/foreign/rawload.c b/libvips/foreign/rawload.c
index 39f89278..98cf4ec5 100644
--- a/libvips/foreign/rawload.c
+++ b/libvips/foreign/rawload.c
@@ -124,21 +124,21 @@ vips_foreign_load_raw_class_init( VipsForeignLoadRawClass *class )
 		_( "Image width in pixels" ),
 		VIPS_ARGUMENT_REQUIRED_INPUT,
 		G_STRUCT_OFFSET( VipsForeignLoadRaw, width ),
-		0, 1000000, 0 );
+		0, VIPS_MAX_COORD, 0 );
 
 	VIPS_ARG_INT( class, "height", 11, 
 		_( "Height" ), 
 		_( "Image height in pixels" ),
 		VIPS_ARGUMENT_REQUIRED_INPUT,
 		G_STRUCT_OFFSET( VipsForeignLoadRaw, height ),
-		0, 1000000, 0 );
+		0, VIPS_MAX_COORD, 0 );
 
 	VIPS_ARG_INT( class, "bands", 12, 
 		_( "Bands" ), 
 		_( "Number of bands in image" ),
 		VIPS_ARGUMENT_REQUIRED_INPUT,
 		G_STRUCT_OFFSET( VipsForeignLoadRaw, bands ),
-		0, 1000000, 0 );
+		0, VIPS_MAX_COORD, 0 );
 
 	VIPS_ARG_UINT64( class, "offset", 13, 
 		_( "Size of header" ), 
diff --git a/libvips/foreign/tiff2vips.c b/libvips/foreign/tiff2vips.c
index fb620d87..e1fa9609 100644
--- a/libvips/foreign/tiff2vips.c
+++ b/libvips/foreign/tiff2vips.c
@@ -1126,9 +1126,9 @@ parse_header( ReadTiff *rtiff, VipsImage *out )
 	 */
 
 	if( width <= 0 || 
-		width > 10000000 || 
+		width > VIPS_MAX_COORD || 
 		height <= 0 || 
-		height > 10000000 ) {
+		height > VIPS_MAX_COORD ) {
 		vips_error( "tiff2vips", 
 			"%s", _( "width/height out of range" ) );
 		return( -1 );
diff --git a/libvips/foreign/vips2jpeg.c b/libvips/foreign/vips2jpeg.c
index 10bae518..dc153732 100644
--- a/libvips/foreign/vips2jpeg.c
+++ b/libvips/foreign/vips2jpeg.c
@@ -69,7 +69,9 @@
  * 	- omit oversized jpeg markers
  * 15/7/15
  * 	- exif tags use @name, not @title
-* 	- set arbitrary exif tags from metadata
+ * 	- set arbitrary exif tags from metadata
+ * 25/11/15	
+ * 	- don't write JFIF headers if we are stripping, thanks Benjamin
  */
 
 /*
@@ -940,9 +942,9 @@ write_vips( Write *write, int qfac, const char *profile,
 #ifdef HAVE_JPEG_EXT_PARAMS
 	/* Reset compression profile to libjpeg defaults
 	 */
-	if( jpeg_c_int_param_supported( &write->cinfo, JINT_COMPRESS_PROFILE ) ) {
-		jpeg_c_set_int_param( &write->cinfo, JINT_COMPRESS_PROFILE, JCP_FASTEST );
-	}
+	if( jpeg_c_int_param_supported( &write->cinfo, JINT_COMPRESS_PROFILE ) )
+		jpeg_c_set_int_param( &write->cinfo, 
+			JINT_COMPRESS_PROFILE, JCP_FASTEST );
 #endif
 
 	/* Rest to default. 
@@ -955,61 +957,62 @@ write_vips( Write *write, int qfac, const char *profile,
 	write->cinfo.optimize_coding = optimize_coding;
 
 #ifdef HAVE_JPEG_EXT_PARAMS
-	/* Apply trellis quantisation to each 8x8 block. Infers "optimize_coding".
+	/* Apply trellis quantisation to each 8x8 block. Implies 
+	 * "optimize_coding".
 	 */
 	if( trellis_quant ) {
-		if ( jpeg_c_bool_param_supported(
-			&write->cinfo, JBOOLEAN_TRELLIS_QUANT ) ) {
+		if( jpeg_c_bool_param_supported( &write->cinfo, 
+			JBOOLEAN_TRELLIS_QUANT ) ) {
 			jpeg_c_set_bool_param( &write->cinfo,
 				JBOOLEAN_TRELLIS_QUANT, TRUE );
 			write->cinfo.optimize_coding = TRUE;
 		}
-		else {
-			vips_warn( "vips2jpeg", "%s", _( "trellis_quant unsupported" ) );
-		}
+		else 
+			vips_warn( "vips2jpeg", 
+				"%s", _( "trellis_quant unsupported" ) );
 	}
-	/* Apply overshooting to samples with extreme values e.g. 0 & 255 for 8-bit.
+
+	/* Apply overshooting to samples with extreme values e.g. 0 & 255 
+	 * for 8-bit.
 	 */
 	if( overshoot_deringing ) {
-		if ( jpeg_c_bool_param_supported(
-			&write->cinfo, JBOOLEAN_OVERSHOOT_DERINGING ) ) {
+		if( jpeg_c_bool_param_supported( &write->cinfo, 
+			JBOOLEAN_OVERSHOOT_DERINGING ) ) 
 			jpeg_c_set_bool_param( &write->cinfo,
 				JBOOLEAN_OVERSHOOT_DERINGING, TRUE );
-		}
-		else {
-			vips_warn( "vips2jpeg", "%s", _( "overshoot_deringing unsupported" ) );
-		}
+		else 
+			vips_warn( "vips2jpeg", 
+				"%s", _( "overshoot_deringing unsupported" ) );
 	}
 	/* Split the spectrum of DCT coefficients into separate scans.
-	 * Requires progressive output. Must be set before jpeg_simple_progression.
+	 * Requires progressive output. Must be set before 
+	 * jpeg_simple_progression.
 	 */
 	if( optimize_scans ) {
 		if( progressive ) {
-			if( jpeg_c_bool_param_supported(
-				&write->cinfo, JBOOLEAN_OPTIMIZE_SCANS ) ) {
-				jpeg_c_set_bool_param( &write->cinfo, JBOOLEAN_OPTIMIZE_SCANS, TRUE );
-			}
-			else {
-				vips_warn( "vips2jpeg", "%s", _( "Ignoring optimize_scans" ) );
-			}
+			if( jpeg_c_bool_param_supported( &write->cinfo, 
+				JBOOLEAN_OPTIMIZE_SCANS ) ) 
+				jpeg_c_set_bool_param( &write->cinfo, 
+					JBOOLEAN_OPTIMIZE_SCANS, TRUE );
+			else 
+				vips_warn( "vips2jpeg", 
+					"%s", _( "Ignoring optimize_scans" ) );
 		}
-		else {
+		else 
 			vips_warn( "vips2jpeg", "%s",
 				_( "Ignoring optimize_scans for baseline" ) );
-		}
 	}
 #else
-	/* Using jpeglib.h without extension parameters, warn of ignored options.
+	/* Using jpeglib.h without extension parameters, warn of ignored 
+	 * options.
 	 */
-	if ( trellis_quant ) {
+	if( trellis_quant ) 
 		vips_warn( "vips2jpeg", "%s", _( "Ignoring trellis_quant" ) );
-	}
-	if ( overshoot_deringing ) {
-		vips_warn( "vips2jpeg", "%s", _( "Ignoring overshoot_deringing" ) );
-	}
-	if ( optimize_scans ) {
+	if( overshoot_deringing ) 
+		vips_warn( "vips2jpeg", 
+			"%s", _( "Ignoring overshoot_deringing" ) );
+	if( optimize_scans ) 
 		vips_warn( "vips2jpeg", "%s", _( "Ignoring optimize_scans" ) );
-	}
 #endif
 
 	/* Enable progressive write.
@@ -1028,6 +1031,11 @@ write_vips( Write *write, int qfac, const char *profile,
 		}
 	}
 
+	/* Don't write the APP0 JFIF headers if we are stripping.
+	 */
+	if( strip ) 
+		write->cinfo.write_JFIF_header = FALSE;
+
 	/* Build compress tables.
 	 */
 	jpeg_start_compress( &write->cinfo, TRUE );
diff --git a/libvips/histogram/hist_local.c b/libvips/histogram/hist_local.c
index 15c518f7..59472ea2 100644
--- a/libvips/histogram/hist_local.c
+++ b/libvips/histogram/hist_local.c
@@ -313,14 +313,14 @@ vips_hist_local_class_init( VipsHistLocalClass *class )
 		_( "Window width in pixels" ),
 		VIPS_ARGUMENT_REQUIRED_INPUT,
 		G_STRUCT_OFFSET( VipsHistLocal, width ),
-		1, 1000000, 1 );
+		1, VIPS_MAX_COORD, 1 );
 
 	VIPS_ARG_INT( class, "height", 5, 
 		_( "Height" ), 
 		_( "Window height in pixels" ),
 		VIPS_ARGUMENT_REQUIRED_INPUT,
 		G_STRUCT_OFFSET( VipsHistLocal, height ),
-		1, 1000000, 1 );
+		1, VIPS_MAX_COORD, 1 );
 }
 
 static void
diff --git a/libvips/include/vips/image.h b/libvips/include/vips/image.h
index 48fc8068..1c354757 100644
--- a/libvips/include/vips/image.h
+++ b/libvips/include/vips/image.h
@@ -47,6 +47,15 @@ extern "C" {
 #define VIPS_MAGIC_INTEL (0xb6a6f208U)
 #define VIPS_MAGIC_SPARC (0x08f2a6b6U)
 
+/* We have a maximum value for a coordinate at various points for sanity
+ * checking. For example, vips_black() has a max with and height. We use int
+ * for width/height so we could go up to 2bn, but it's good to have a lower
+ * value set so we can see crazy numbers early.
+ *
+ * This was 1m for a while, but someone found a use for a 4m wide image.
+ */
+#define VIPS_MAX_COORD (10000000)
+
 typedef enum {
 	VIPS_DEMAND_STYLE_ERROR = -1,	
 	VIPS_DEMAND_STYLE_SMALLTILE,	
@@ -429,6 +438,8 @@ VipsImage *vips_image_new_from_file_raw( const char *filename,
 	int xsize, int ysize, int bands, guint64 offset );
 VipsImage *vips_image_new_from_memory( const void *data, size_t size,
 	int width, int height, int bands, VipsBandFormat format );
+VipsImage *vips_image_new_from_memory_copy( const void *data, size_t size,
+	int width, int height, int bands, VipsBandFormat format );
 VipsImage *vips_image_new_from_buffer( const void *buf, size_t len, 
 	const char *option_string, ... )
 	__attribute__((sentinel));
diff --git a/libvips/iofuncs/generate.c b/libvips/iofuncs/generate.c
index 41a6c3da..e24cd1d7 100644
--- a/libvips/iofuncs/generate.c
+++ b/libvips/iofuncs/generate.c
@@ -193,7 +193,7 @@ vips__link_break_all( VipsImage *image )
 
 typedef struct _LinkMap {
 	gboolean upstream;
-	int *serial;
+	int serial;
 	VipsSListMap2Fn fn;
 	void *a;
 	void *b;
@@ -206,9 +206,9 @@ vips__link_mapp( VipsImage *image, LinkMap *map )
 
 	/* Loop?
 	 */
-	if( image->serial == *map->serial )
+	if( image->serial == map->serial )
 		return( NULL );
-	image->serial = *map->serial;
+	image->serial = map->serial;
 
 	if( (res = map->fn( image, map->a, map->b )) )
 		return( res );
@@ -240,8 +240,6 @@ vips__link_map( VipsImage *image, gboolean upstream,
 	GSList *p;
 	void *result;
 
-	serial += 1;
-
 	images = NULL;
 
 	/* The function might do anything, including removing images
@@ -251,13 +249,19 @@ vips__link_map( VipsImage *image, gboolean upstream,
 	 */
 
 	map.upstream = upstream;
-	map.serial = &serial;
 	map.fn = (VipsSListMap2Fn) vips__link_map_cb;
 	map.a = (void *) &images;
 	map.b = NULL;
 
+	/* We will be walking the tree of images and updating the ->serial
+	 * member. There will be intense confusion if two threads try to do
+	 * this at the same time.
+	 */
 	g_mutex_lock( vips__global_lock );
 
+	serial += 1;
+	map.serial = serial;
+
 	vips__link_mapp( image, &map ); 
 
 	for( p = images; p; p = p->next ) 
diff --git a/libvips/iofuncs/image.c b/libvips/iofuncs/image.c
index 5969857b..d9608f6f 100644
--- a/libvips/iofuncs/image.c
+++ b/libvips/iofuncs/image.c
@@ -6,6 +6,8 @@
  * 	- vips_image_write() didn't ref non-partial sources
  * 18/4/15
  * 	- add vips_image_copy_memory()
+ * 25/11/15
+ * 	- add vips_image_new_from_memory_copy()
  */
 
 /*
@@ -1117,21 +1119,21 @@ vips_image_class_init( VipsImageClass *class )
 		_( "Image width in pixels" ),
 		VIPS_ARGUMENT_SET_ALWAYS,
 		G_STRUCT_OFFSET( VipsImage, Xsize ),
-		1, 1000000000, 1 );
+		1, VIPS_MAX_COORD, 1 );
 
 	VIPS_ARG_INT( class, "height", 3, 
 		_( "Height" ), 
 		_( "Image height in pixels" ),
 		VIPS_ARGUMENT_SET_ALWAYS,
 		G_STRUCT_OFFSET( VipsImage, Ysize ),
-		1, 1000000000, 1 );
+		1, VIPS_MAX_COORD, 1 );
 
 	VIPS_ARG_INT( class, "bands", 4, 
 		_( "Bands" ), 
 		_( "Number of bands in image" ),
 		VIPS_ARGUMENT_SET_ALWAYS,
 		G_STRUCT_OFFSET( VipsImage, Bands ),
-		1, 1000000000, 1 );
+		1, VIPS_MAX_COORD, 1 );
 
 	VIPS_ARG_ENUM( class, "format", 5, 
 		_( "Format" ), 
@@ -1173,14 +1175,14 @@ vips_image_class_init( VipsImageClass *class )
 		_( "Horizontal offset of origin" ),
 		VIPS_ARGUMENT_SET_ALWAYS,
 		G_STRUCT_OFFSET( VipsImage, Xoffset ),
-		-1000000, 1000000, 0 );
+		-VIPS_MAX_COORD, VIPS_MAX_COORD, 0 );
 
 	VIPS_ARG_INT( class, "yoffset", 11, 
 		_( "Yoffset" ), 
 		_( "Vertical offset of origin" ),
 		VIPS_ARGUMENT_SET_ALWAYS,
 		G_STRUCT_OFFSET( VipsImage, Yoffset ),
-		-1000000, 1000000, 0 );
+		-VIPS_MAX_COORD, VIPS_MAX_COORD, 0 );
 
 	VIPS_ARG_STRING( class, "filename", 12, 
 		_( "Filename" ),
@@ -1415,6 +1417,8 @@ vips_image_invalidate_all_cb( VipsImage *image )
 void
 vips_image_invalidate_all( VipsImage *image )
 {
+	VIPS_DEBUG_MSG( "vips_image_invalidate_all: %p\n", image );
+
 	(void) vips__link_map( image, FALSE,
 		(VipsSListMap2Fn) vips_image_invalidate_all_cb, NULL, NULL );
 }
@@ -1979,9 +1983,15 @@ vips_image_new_from_file_raw( const char *filename,
  * responsibility for the area of memory, it's up to you to make sure it's
  * freed when the image is closed. See for example #VipsObject::close.
  *
+ * Because VIPS is "borrowing" @data from the caller, this function is
+ * extremely dangerous. Unless you are very careful, you will get crashes or
+ * memory corruption. Use vips_image_new_from_memory_copy() instead if you are
+ * at all unsure. 
+ *
  * Use vips_copy() to set other image properties. 
  *
- * See also: vips_image_new(), vips_image_write_to_memory().
+ * See also: vips_image_new(), vips_image_write_to_memory(),
+ * vips_image_new_from_memory_copy().
  *
  * Returns: (transfer full): the new #VipsImage, or %NULL on error.
  */
@@ -2014,7 +2024,7 @@ vips_image_new_from_memory( const void *data, size_t size,
 	if( size > 0 && 
 		size < VIPS_IMAGE_SIZEOF_IMAGE( image ) ) {
 		vips_error( "VipsImage",
-			_( "buffer too small --- "
+			_( "memory area too small --- "
 				"should be %zd bytes, you passed %zd" ),
 			VIPS_IMAGE_SIZEOF_IMAGE( image ), size ); 
 		VIPS_UNREF( image );
@@ -2024,6 +2034,54 @@ vips_image_new_from_memory( const void *data, size_t size,
 	return( image );
 }
 
+static void
+vips_image_new_from_memory_copy_cb( VipsImage *image, void *data_copy )
+{
+	vips_tracked_free( data_copy );
+}
+
+/**
+ * vips_image_new_from_memory_copy:
+ * @data: (array length=size) (element-type guint8) (transfer none): start of memory area
+ * @size: length of memory area
+ * @width: image width
+ * @height: image height
+ * @bands: image bands (or bytes per pixel)
+ * @format: image format
+ *
+ * Like vips_image_new_from_memory(), but VIPS will make a copy of the memory 
+ * area. This
+ * means more memory use and an extra copy operation, but is much simpler and
+ * safer. 
+ *
+ * See also: vips_image_new_from_memory().
+ *
+ * Returns: (transfer full): the new #VipsImage, or %NULL on error.
+ */
+VipsImage *
+vips_image_new_from_memory_copy( const void *data, size_t size,
+	int width, int height, int bands, VipsBandFormat format )
+{
+	void *data_copy;
+	VipsImage *image;
+
+	vips_check_init();
+
+	if( !(data_copy = vips_tracked_malloc( size )) )
+		return( NULL );
+	memcpy( data_copy, data, size );
+	if( !(image = vips_image_new_from_memory( data_copy, size, 
+		width, height, bands, format )) ) {
+		vips_tracked_free( data_copy );
+		return( NULL );
+	}
+
+	g_signal_connect( image, "close", 
+		G_CALLBACK( vips_image_new_from_memory_copy_cb ), data_copy );
+
+	return( image );
+}
+
 /**
  * vips_image_new_from_buffer:
  * @buf: (array length=len) (element-type guint8) (transfer none): image data
diff --git a/libvips/iofuncs/sinkscreen.c b/libvips/iofuncs/sinkscreen.c
index 29e4c512..aea4616c 100644
--- a/libvips/iofuncs/sinkscreen.c
+++ b/libvips/iofuncs/sinkscreen.c
@@ -7,6 +7,9 @@
  * 	  mem use
  * 20/1/14
  * 	- bg render thread quits on shutdown
+ * 1/12/15
+ * 	- don't do anything to out or mask after they have closed
+ * 	- only run the bg render thread when there's work to do
  */
 
 /*
@@ -135,6 +138,11 @@ typedef struct _Render {
 	/* Hash of tiles with positions. Tiles can be dirty or painted.
 	 */
 	GHashTable *tiles;
+
+	/* A shutdown flag. If ->out or ->mask close, we must no longer do
+	 * anything to them until we shut down too.
+	 */
+	gboolean shutdown;
 } Render;
 
 /* Our per-thread state.
@@ -158,10 +166,6 @@ G_DEFINE_TYPE( RenderThreadState, render_thread_state, VIPS_TYPE_THREAD_STATE );
  */
 static GThread *render_thread = NULL;
 
-/* Number of renders with dirty tiles. render_thread queues up on this.
- */
-static VipsSemaphore render_dirty_sem;
-
 /* Set this to ask the render thread to quit.
  */
 static gboolean render_kill = FALSE;
@@ -217,14 +221,8 @@ render_free( Render *render )
 	g_assert( render->ref_count == 0 );
 
 	g_mutex_lock( render_dirty_lock );
-	if( g_slist_find( render_dirty_all, render ) ) {
+	if( g_slist_find( render_dirty_all, render ) ) 
 		render_dirty_all = g_slist_remove( render_dirty_all, render );
-
-		/* We could vips_semaphore_upn( &render_dirty_sem, -1 ), but
-		 * what's the point. We'd just wake up the bg thread
-		 * for no reason.
-		 */
-	}
 	g_mutex_unlock( render_dirty_lock );
 
 	vips_g_mutex_free( render->ref_count_lock );
@@ -275,22 +273,16 @@ render_unref( Render *render )
 	return( 0 );
 }
 
-/* Wait for a render with dirty tiles. 
+/* Get the first render with dirty tiles. 
  */
 static Render *
 render_dirty_get( void )
 {
 	Render *render;
 
-	/* Wait for a render with dirty tiles.
-	 */
-	vips_semaphore_down( &render_dirty_sem );
-
 	g_mutex_lock( render_dirty_lock );
 
-	/* Just take the head of the jobs list ... we sort when we add. If
-	 * render_free() is called between our semaphore letting us in
-	 * and the _lock(), render_dirty_all can be NULL.
+	/* Just take the head of the jobs list ... we sort when we add. 
 	 */
 	render = NULL;
 	if( render_dirty_all ) {
@@ -433,51 +425,22 @@ render_work( VipsThreadState *state, void *a )
 	/* All downstream images must drop caches, since we've (effectively)
 	 * modified render->out. 
 	 */
-	vips_image_invalidate_all( render->out ); 
-	if( render->mask ) 
+	if( !render->shutdown ) 
+		vips_image_invalidate_all( render->out ); 
+	if( !render->shutdown &&
+		render->mask ) 
 		vips_image_invalidate_all( render->mask ); 
 
 	/* Now clients can update.
 	 */
-	if( render->notify ) 
+	if( !render->shutdown &&
+		render->notify ) 
 		render->notify( render->out, &tile->area, render->a );
 
 	return( 0 );
 }
 
-static int       
-render_dirty_sort( Render *a, Render *b )
-{
-	return( b->priority - a->priority );
-}
-
-/* Add to the jobs list, if it has work to be done.
- */
-static void
-render_dirty_put( Render *render )
-{
-	g_mutex_lock( render_dirty_lock );
-
-	if( render->dirty ) {
-		if( !g_slist_find( render_dirty_all, render ) ) {
-			render_dirty_all = g_slist_prepend( render_dirty_all, 
-				render );
-			render_dirty_all = g_slist_sort( render_dirty_all,
-				(GCompareFunc) render_dirty_sort );
-
-			/* Ask the bg thread to stop and reschedule, if it's
-			 * running.
-			 */
-			VIPS_DEBUG_MSG_GREEN( "render_dirty_put: "
-				"reschedule\n" );
-			render_reschedule = TRUE;
-
-			vips_semaphore_up( &render_dirty_sem );
-		}
-	}
-
-	g_mutex_unlock( render_dirty_lock );
-}
+static void render_dirty_put( Render *render );
 
 /* Main loop for RenderThreads.
  */
@@ -515,9 +478,15 @@ render_thread_main( void *client )
 		render_unref( render );
 	}
 
+	/* We are exiting, so render_thread must now be NULL.
+	 */
+	render_thread = NULL; 
+
 	return( NULL );
 }
 
+/* Called from vips_shutdown().
+ */
 void
 vips__render_shutdown( void )
 {
@@ -532,36 +501,52 @@ vips__render_shutdown( void )
 		GThread *thread;
 
 		thread = render_thread;
-		render_thread = NULL; 
 
 		g_mutex_unlock( render_dirty_lock );
 
 		render_reschedule = TRUE;
 		render_kill = TRUE;
-		vips_semaphore_up( &render_dirty_sem );
 		(void) g_thread_join( thread );
 	}
 	else
 		g_mutex_unlock( render_dirty_lock );
 }
 
-/* Create our set of RenderThread. Assume we're single-threaded here.
- */
-static int
-render_thread_create( void )
+static int       
+render_dirty_sort( Render *a, Render *b )
 {
-	if( !render_dirty_lock ) {
-		render_dirty_lock = vips_g_mutex_new();
-		vips_semaphore_init( &render_dirty_sem, 0, "render_dirty_sem" );
+	return( b->priority - a->priority );
+}
+
+/* Add to the jobs list, if it has work to be done.
+ */
+static void
+render_dirty_put( Render *render )
+{
+	g_mutex_lock( render_dirty_lock );
+
+	if( render->dirty ) {
+		if( !g_slist_find( render_dirty_all, render ) ) {
+			render_dirty_all = g_slist_prepend( render_dirty_all, 
+				render );
+			render_dirty_all = g_slist_sort( render_dirty_all,
+				(GCompareFunc) render_dirty_sort );
+
+			/* Make sure there is a bg render thread, and get it to
+			 * reschedule. 
+			 */
+			if( !render_thread ) {
+				render_thread = vips_g_thread_new( "sink_screen",
+					render_thread_main, NULL );
+				g_assert( render_thread ); 
+			}
+			VIPS_DEBUG_MSG_GREEN( "render_dirty_put: "
+				"reschedule\n" );
+			render_reschedule = TRUE;
+		}
 	}
 
-	if( !render_thread ) {
-		if( !(render_thread = vips_g_thread_new( "sink_screen",
-			render_thread_main, NULL )) ) 
-			return( -1 );
-	}
-
-	return( 0 );
+	g_mutex_unlock( render_dirty_lock );
 }
 
 static guint
@@ -590,6 +575,13 @@ render_close_cb( VipsImage *image, Render *render )
 {
 	VIPS_DEBUG_MSG_AMBER( "render_close_cb\n" );
 
+	/* The output image or mask are closing. This render will stick 
+	 * around for a while, since threads can still be running, but it 
+	 * must no longer reference ->out or ->mask (for example, invalidating
+	 * them).
+	 */
+	render->shutdown = TRUE;
+
 	render_unref( render );
 
 	/* If this render is being worked on, we want to jog the bg thread, 
@@ -639,6 +631,8 @@ render_new( VipsImage *in, VipsImage *out, VipsImage *mask,
 
 	render->dirty = NULL;
 
+	render->shutdown = FALSE;
+
 	/* Both out and mask must close before we can free the render.
 	 */
 	g_signal_connect( out, "close", 
@@ -918,20 +912,12 @@ tile_copy( Tile *tile, VipsRegion *to )
 	}
 }
 
-static void *
-image_start( IMAGE *out, void *a, void *b )
-{
-	Render *render = (Render *) a;
-
-	return( vips_region_new( render->in ) );
-}
-
 /* Loop over the output region, filling with data from cache.
  */
 static int
 image_fill( VipsRegion *out, void *seq, void *a, void *b, gboolean *stop )
 {
-	Render *render = (Render *) a;
+	Render *render = (Render *) b;
 	int tile_width = render->tile_width;
 	int tile_height = render->tile_height;
 	VipsRegion *reg = (VipsRegion *) seq;
@@ -979,16 +965,6 @@ image_fill( VipsRegion *out, void *seq, void *a, void *b, gboolean *stop )
 	return( 0 );
 }
 
-static int
-image_stop( void *seq, void *a, void *b )
-{
-	VipsRegion *reg = (VipsRegion *) seq;
-
-	g_object_unref( reg );
-
-	return( 0 );
-}
-
 /* The mask image is 255 / 0 for the state of painted for each tile.
  */
 static int
@@ -1038,6 +1014,12 @@ mask_fill( VipsRegion *out, void *seq, void *a, void *b, gboolean *stop )
 	return( 0 );
 }
 
+static void
+vips_sink_screen_init( void )
+{
+	render_dirty_lock = vips_g_mutex_new();
+}
+
 /**
  * vips_sink_screen:
  * @in: input image
@@ -1095,12 +1077,11 @@ vips_sink_screen( VipsImage *in, VipsImage *out, VipsImage *mask,
 	int priority,
 	VipsSinkNotify notify_fn, void *a )
 {
+	static GOnce once = G_ONCE_INIT;
+
 	Render *render;
 
-	/* Make sure the bg work threads are ready.
-	 */
-	if( render_thread_create() )
-		return( -1 );
+	g_once( &once, (GThreadFunc) vips_sink_screen_init, NULL );
 
 	if( tile_width <= 0 || tile_height <= 0 || 
 		max_tiles < -1 ) {
@@ -1131,7 +1112,7 @@ vips_sink_screen( VipsImage *in, VipsImage *out, VipsImage *mask,
 	VIPS_DEBUG_MSG( "vips_sink_screen: max = %d, %p\n", max_tiles, render );
 
 	if( vips_image_generate( out, 
-		image_start, image_fill, image_stop, render, NULL ) )
+		vips_start_one, image_fill, vips_stop_one, in, render ) )
 		return( -1 );
 	if( mask && 
 		vips_image_generate( mask, 
diff --git a/libvips/resample/mapim.c b/libvips/resample/mapim.c
index 36431a10..b1354aa5 100644
--- a/libvips/resample/mapim.c
+++ b/libvips/resample/mapim.c
@@ -183,9 +183,9 @@ vips_mapim_region_minmax( VipsRegion *region, VipsRect *r, VipsRect *bounds )
 		TYPE py = p1[1]; \
 		\
 		if( px < 0 || \
-			px > resample->in->Xsize || \
+			px >= resample->in->Xsize || \
 			py < 0 || \
-			py > resample->in->Ysize ) { \
+			py >= resample->in->Ysize ) { \
 			for( z = 0; z < ps; z++ )  \
 				q[z] = 0; \
 		} \