add sequential mode to vips7

the tiff and jpg readers let you give :seq as well

ChangeLog

@@ -8,6 +8,7 @@
 - vipsthumbnail no longer removes profiles by default
 - much more gentle sharpening in thumbnails
 - added "minimise" signal, used by tilecache to drop
+- add :seq support to im_tiff2vips(), im_jpeg2vips() ... helps ruby-vips
 
 18/6/12 started 7.28.9
 - slightly more memory debugging output

TODO

@@ -1,9 +1,10 @@
-- tile cache doesn't need to copy if request fits within a tile
+- vips_image_minimise_all( im );
 
-  though doing a copy means that we can safely drop the cache without leaving
+	call this at the end of thereadpool_run(), doesnt seem to trigger the
-  dangling pointers
+	minimise callback on tilecache?
+
+	it does trigger it if we turn OFF seq mode??! how odd
 
-- could jpeg load via memory buffer support minimise too?
 
 
 blocking bugs

libvips/conversion/tilecache.c

@@ -15,6 +15,8 @@
  * 	- use im_prepare_to() and avoid making a sequence for every cache tile
  * 5/12/11
  * 	- rework as a class
+ * 23/6/12
+ * 	- listen for "minimise" signal
  */
 
 /*
@@ -346,6 +348,14 @@ vips_tile_cache_gen( VipsRegion *or,
 
 	g_mutex_lock( cache->lock );
 
+	/* If the output region fits within a tile (tiles can become quite
+	 * large for seq caches, for example), we could save a copy by routing
+	 * the output region directly to the tile.
+	 *
+	 * However this would mean that tile drop on minimise could then leave
+	 * dangling pointers, if minimuse was called on an active pipeline.
+	 */
+
 	VIPS_DEBUG_MSG( "vips_tile_cache_gen: "
 		"left = %d, top = %d, width = %d, height = %d\n",
 		r->left, r->top, r->width, r->height );
@@ -383,8 +393,6 @@ vips_tile_cache_gen( VipsRegion *or,
 static void
 vips_tile_cache_minimise( VipsImage *image, VipsTileCache *cache )
 {
-	printf( "vips_tile_cache_minimise:\n" );
-
 	vips_tile_cache_drop_all( cache );
 }
 

libvips/deprecated/im_jpeg2vips.c

@@ -52,6 +52,7 @@ im_jpeg2vips( const char *name, IMAGE *out )
 	char *p, *q;
 	int shrink;
 	gboolean fail_on_warn;
+	gboolean sequential;
 	VipsImage *t;
 
 	/* By default, we ignore any warnings. We want to get as much of
@@ -64,6 +65,7 @@ im_jpeg2vips( const char *name, IMAGE *out )
 	im_filename_split( name, filename, mode );
 	p = &mode[0];
 	shrink = 1;
+	sequential = FALSE;
 	if( (q = im_getnextoption( &p )) ) {
 		shrink = atoi( q );
 
@@ -78,10 +80,15 @@ im_jpeg2vips( const char *name, IMAGE *out )
 		if( im_isprefix( "fail", q ) ) 
 			fail_on_warn = TRUE;
 	}
+	if( (q = im_getnextoption( &p )) ) {
+		if( im_isprefix( "seq", q ) )
+			sequential = TRUE;
+	}
 
 	if( vips_jpegload( filename, &t, 
 		"shrink", shrink,
 		"fail", fail_on_warn,
+		"sequential", sequential,
 		NULL ) )
 		return( -1 );
 

libvips/deprecated/im_tiff2vips.c

@@ -55,6 +55,7 @@ im_tiff2vips( const char *name, IMAGE *out )
 	char mode[FILENAME_MAX];
 	char *p, *q;
 	int page;
+	gboolean sequential;
 	VipsImage *t;
 
 	im_filename_split( name, filename, mode );
@@ -64,9 +65,14 @@ im_tiff2vips( const char *name, IMAGE *out )
 	if( (q = im_getnextoption( &p )) ) {
 		page = atoi( q );
 	}
+	if( (q = im_getnextoption( &p )) ) {
+		if( im_isprefix( "seq", q ) )
+			sequential = TRUE;
+	}
 
 	if( vips_tiffload( filename, &t, 
 		"page", page,
+		"sequential", sequential,
 		NULL ) )
 		return( -1 );
 	if( vips_image_write( t, out ) ) {

libvips/foreign/foreign.c

@@ -782,6 +782,12 @@ vips_foreign_load_start( VipsImage *out, void *a, void *b )
 		 */
 		if( !vips_foreign_load_iscompat( load->real, out ) )
 			return( NULL );
+
+		/* We have to tell vips that out depends on real. We've set
+		 * the demand hint below, but not given an input there.
+		 */
+		vips_demand_hint( load->out, load->out->dhint, 
+			load->real, NULL );
 	}
 
 	return( vips_region_new( load->real ) );

libvips/foreign/jpeg2vips.c

@@ -905,7 +905,7 @@ read_jpeg_image( ReadJpeg *jpeg, VipsImage *out )
 	jpeg->decompressing = TRUE;
 
 #ifdef DEBUG
-	printf( "read_jpeg_image: starting deompress\n" );
+	printf( "read_jpeg_image: starting decompress\n" );
 #endif /*DEBUG*/
 
 	if( vips_image_generate( t[0], 

libvips/iofuncs/generate.c

@@ -329,7 +329,7 @@ vips_demand_hint_array( VipsImage *image, VipsDemandStyle hint, VipsImage **in )
 	for( i = 0; i < len; i++ )
 		vips__link_make( in[i], image );
 
-	/* Set a flag on the image to say we remember to call this thing.
+	/* Set a flag on the image to say we remembered to call this thing.
 	 * vips_image_generate() and friends check this.
 	 */
 	image->hint_set = TRUE;

libvips/iofuncs/image.c

@@ -1111,8 +1111,6 @@ vips_image_minimise_all_cb( VipsImage *image )
 void 
 vips_image_minimise_all( VipsImage *image )
 {
-	printf( "vips_image_minimise_all:\n" ); 
-
 	(void) vips__link_map( image, TRUE,
 		(VipsSListMap2Fn) vips_image_minimise_all_cb, NULL, NULL );
 }

libvips/iofuncs/threadpool.c

@@ -913,8 +913,6 @@ vips_threadpool_run( VipsImage *im,
 
 	vips_threadpool_free( pool );
 
-	/* Ask the pipeline to drop into low-mem-use mode now we're done.
-	 */
 	vips_image_minimise_all( im );
 
 	return( result );