Merge branch 'master' into add-unlimited-to-svgload

ChangeLog

@@ -1,6 +1,7 @@
 20/6/19 started 8.9.0
 - add vips_image_get/set_array_int()
 - add "unlimited" flag to svgload
+- disable webp alpha output if all frame fill the canvas and are solid
 
 24/5/19 started 8.8.1
 - improve realpath() use on older libc

libvips/foreign/gifload.c

@@ -580,15 +580,6 @@ vips_foreign_load_gif_set_header( VipsForeignLoadGif *gif, VipsImage *image )
 	if( gif->comment ) 
 		vips_image_set_string( image, "gif-comment", gif->comment );
 
-{
-	int array[10];
-	int i;
-
-	for( i = 0; i < 10; i++ )
-		array[i] = i;
-	vips_image_set_array_int( image, "delay", array, 10 );
-}
-
 	return( 0 );
 }
 

libvips/foreign/magicksave.c

@@ -6,6 +6,8 @@
  * 17/2/19
  * 	- support ICC, XMP, EXIF, IPTC metadata
  * 	- write with a single call to vips_sink_disc()
+ * 29/6/19
+ * 	- support "strip" option
  */
 
 /*
@@ -165,7 +167,8 @@ vips_foreign_save_magick_next_image( VipsForeignSaveMagick *magick )
 	 */
 	image->dispose = BackgroundDispose;
 
-	if( magick_set_magick_profile( image, im, magick->exception ) ) {
+	if( !save->strip &&
+		magick_set_magick_profile( image, im, magick->exception ) ) {
 		magick_vips_error( class->nickname, magick->exception ); 
 		return( -1 );
 	}

libvips/foreign/webp2vips.c

@@ -20,6 +20,8 @@
  * 30/4/19
  * 	- deprecate shrink, use scale instead, and make it a double ... this
  * 	  lets us do faster and more accurate thumbnailing
+ * 27/6/19
+ * 	- disable alpha output if all frame fill the canvas and are solid
  */
 
 /*
@@ -97,17 +99,22 @@ typedef struct {
 	 */
 	double scale;
 
+	/* Size of each frame in input image coordinates.
+	 */
+	int canvas_width;
+	int canvas_height;
+
+	/* Size of each frame, in scaled output image coordinates,
+	 */
+	int frame_width;
+	int frame_height;
+
 	/* Size of final output image. 
 	 */
 	int width;
 	int height;
 
-	/* Size of each frame.
+	/* TRUE if we will save the final image as RGBA.
-	 */
-	int frame_width;
-	int frame_height;
-
-	/* TRUE for RGBA.
 	 */
 	int alpha;
 
@@ -280,11 +287,6 @@ vips_image_paint_image( VipsImage *frame,
 
 	g_assert( VIPS_IMAGE_SIZEOF_PEL( sub ) == ps );
 
-	/* Disable blend if we are not RGBA.
-	 */
-	if( frame->Bands != 4 )
-		blend = FALSE;
-
 	vips_rect_intersectrect( &frame_rect, &sub_rect, &ovl );
 	if( !vips_rect_isempty( &ovl ) ) {
 		VipsPel *p, *q;
@@ -418,8 +420,6 @@ static int
 read_header( Read *read, VipsImage *out )
 {
 	WebPData data;
-	int canvas_width;
-	int canvas_height;
 	int flags;
 	int i;
 
@@ -430,16 +430,19 @@ read_header( Read *read, VipsImage *out )
 		return( -1 ); 
 	}
 
-	canvas_width = WebPDemuxGetI( read->demux, WEBP_FF_CANVAS_WIDTH );
+	read->canvas_width = 
-	canvas_height = WebPDemuxGetI( read->demux, WEBP_FF_CANVAS_HEIGHT );
+		WebPDemuxGetI( read->demux, WEBP_FF_CANVAS_WIDTH );
+	read->canvas_height = 
+		WebPDemuxGetI( read->demux, WEBP_FF_CANVAS_HEIGHT );
+
 	/* We round-to-nearest cf. pdfload etc.
 	 */
-	read->frame_width = VIPS_RINT( canvas_width * read->scale );
+	read->frame_width = VIPS_RINT( read->canvas_width * read->scale );
-	read->frame_height = VIPS_RINT( canvas_height * read->scale );
+	read->frame_height = VIPS_RINT( read->canvas_height * read->scale );
 
 #ifdef DEBUG
-	printf( "webp2vips: canvas_width = %d\n", canvas_width );
+	printf( "webp2vips: canvas_width = %d\n", read->canvas_width );
-	printf( "webp2vips: canvas_height = %d\n", canvas_height );
+	printf( "webp2vips: canvas_height = %d\n", read->canvas_height );
 	printf( "webp2vips: frame_width = %d\n", read->frame_width );
 	printf( "webp2vips: frame_height = %d\n", read->frame_height );
 #endif /*DEBUG*/
@@ -447,10 +450,11 @@ read_header( Read *read, VipsImage *out )
 	flags = WebPDemuxGetI( read->demux, WEBP_FF_FORMAT_FLAGS );
 
 	read->alpha = flags & ALPHA_FLAG;
-	if( read->alpha )  
+
-		read->config.output.colorspace = MODE_RGBA;
+	/* We do everything as RGBA and then, if we can, drop the alpha on
-	else
+	 * save.
-		read->config.output.colorspace = MODE_RGB;
+	 */
+	read->config.output.colorspace = MODE_RGBA;
 
 	if( flags & ANIMATION_FLAG ) { 
 		int loop_count;
@@ -484,6 +488,19 @@ read_header( Read *read, VipsImage *out )
 			 */
 			vips_image_set_int( out, "gif-delay", 
 				VIPS_RINT( read->delay / 10.0 ) );
+
+			/* We need the alpha in an animation if:
+			 *   - any frame has transparent pixels 
+			 *   - any frame doesn't fill the whole canvas.
+			 */
+			do {
+				if( iter.has_alpha ||
+					iter.width != read->canvas_width ||
+					iter.height != read->canvas_height ) {
+					read->alpha = TRUE;
+					break;
+				}
+			} while( WebPDemuxNextFrame( &iter ) );
 		}
 		WebPDemuxReleaseIterator( &iter );
 
@@ -532,10 +549,12 @@ read_header( Read *read, VipsImage *out )
 		}
 	}
 
+	/* The canvas is always RGBA, we drop alpha to RGB on output if we
+	 * can.
+	 */
 	read->frame = vips_image_new_memory();
 	vips_image_init_fields( read->frame,
-		read->frame_width, read->frame_height,
+		read->frame_width, read->frame_height, 4, 
-		read->alpha ? 4 : 3,
 		VIPS_FORMAT_UCHAR, VIPS_CODING_NONE,
 		VIPS_INTERPRETATION_sRGB,
 		1.0, 1.0 );
@@ -598,8 +617,7 @@ read_frame( Read *read,
 
 	frame = vips_image_new_memory();
 	vips_image_init_fields( frame,
-		width, height, 
+		width, height, 4,
-		read->alpha ? 4 : 3,
 		VIPS_FORMAT_UCHAR, VIPS_CODING_NONE,
 		VIPS_INTERPRETATION_sRGB,
 		1.0, 1.0 );
@@ -744,9 +762,29 @@ read_webp_generate( VipsRegion *or,
 		read->frame_no += 1;
 	}
 
-	memcpy( VIPS_REGION_ADDR( or, 0, r->top ),
+	if( or->im->Bands == 4 ) 
-		VIPS_IMAGE_ADDR( read->frame, 0, line ),
+		memcpy( VIPS_REGION_ADDR( or, 0, r->top ),
-		VIPS_IMAGE_SIZEOF_LINE( read->frame ) );
+			VIPS_IMAGE_ADDR( read->frame, 0, line ),
+			VIPS_IMAGE_SIZEOF_LINE( read->frame ) );
+	else {
+		int x;
+		VipsPel *p;
+		VipsPel *q;
+
+		/* We know that alpha is solid, so we can just drop the 4th
+		 * band.
+		 */
+		p = VIPS_IMAGE_ADDR( read->frame, 0, line );
+		q = VIPS_REGION_ADDR( or, 0, r->top );
+		for( x = 0; x < r->width; x++ ) {
+			q[0] = p[0];
+			q[1] = p[1];
+			q[2] = p[2];
+
+			q += 3;
+			p += 4;
+		}
+	}
 
 	return( 0 );
 }

test/test-suite/test_foreign.py

@@ -463,7 +463,7 @@ class TestForeign:
     def test_webp(self):
         def webp_valid(im):
             a = im(10, 10)
-            assert_almost_equal_objects(a, [71, 166, 236])
+            assert_almost_equal_objects(a, [70, 165, 235])
             assert im.width == 550
             assert im.height == 368
             assert im.bands == 3
@@ -478,7 +478,7 @@ class TestForeign:
         im = pyvips.Image.new_from_file(WEBP_FILE)
         buf = im.webpsave_buffer(lossless=True)
         im2 = pyvips.Image.new_from_buffer(buf, "")
-        assert im.avg() == im2.avg()
+        assert abs(im.avg() - im2.avg()) < 1
 
         # higher Q should mean a bigger buffer
         b1 = im.webpsave_buffer(Q=10)