Set default pixel scale to 1 (#183)

Closes #182.

Author: aliddell

src/storage.rs

@@ -129,7 +129,7 @@ impl Default for StorageProperties {
             filename: Default::default(),
             external_metadata_json: Default::default(),
             first_frame_id: Default::default(),
-            pixel_scale_um: Default::default(),
+            pixel_scale_um: (1., 1.), // Default to 1.0 um/pixel (square pixels)
             acquisition_dimensions: Default::default(),
             enable_multiscale: Default::default(),
         }

tests/test_basic.py

@@ -32,6 +32,11 @@ def test_set():
     assert t.enable
 
 
+def test_storage_properties_pixel_scale_defaults_to_1():
+    storage = acquire.StorageProperties()
+    assert storage.pixel_scale_um == (1.0, 1.0)
+
+
 def test_list_devices(runtime: Runtime):
     dm = runtime.device_manager()
     for d in dm.devices():