Fix sizes of GIF and ICO before save

vips/vips.go

@@ -31,6 +31,8 @@ type Image struct {
 var (
 	typeSupportLoad sync.Map
 	typeSupportSave sync.Map
+
+	gifResolutionLimit int
 )
 
 var vipsConf struct {
@@ -69,6 +71,8 @@ func Init() error {
 		C.vips_cache_set_trace(C.gboolean(1))
 	}
 
+	gifResolutionLimit = int(C.gif_resolution_limit())
+
 	vipsConf.JpegProgressive = gbool(config.JpegProgressive)
 	vipsConf.PngInterlaced = gbool(config.PngInterlaced)
 	vipsConf.PngQuantize = gbool(config.PngQuantize)
@@ -183,6 +187,10 @@ func SupportsSave(it imagetype.Type) bool {
 	return sup
 }
 
+func GifResolutionLimit() int {
+	return gifResolutionLimit
+}
+
 func gbool(b bool) C.gboolean {
 	if b {
 		return C.gboolean(1)