Fixed Absorption/mask volumes creation for big volumes

Signed-off-by: Nicola Vigano <nicola.vigano@esrf.fr>

5_reconstruction/GtGuiThresholdVolume.m

@@ -25,7 +25,7 @@ classdef GtGuiThresholdVolume < GtGuiThresholdGrain
             end
 
             if (filerIndex == 1)
-                save(fullfile(pathname, filename), 'vol');
+                save(fullfile(pathname, filename), 'vol', '-v7.3');
             else
                 edf_write(vol, fullfile(pathname, filename));
             end